Interactions of Puccinia striiformis and Mycosphaerella graminicola on wheat
by Ricardo Burrows Madariaga
A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Plant
Pathology
Montana State University
© Copyright by Ricardo Burrows Madariaga (1984)
Abstract:
Puccinia striiformis and Mycosphaerella graminicola are frequently found attacking the same wheat
leaf. The effect of one pathogen upon the other, and the effects of the interactions between pathogens
upon the host-pathogen interactions are the subjects of these studies.
Seedlings of four spring wheat cultivars were inoculated at different time combinations of P. striiformis
and graminicola. In susceptible cul tivars, inoculations with both pathogens resulted in similar host
tissue damage to the damage obtained by inoculation with each organism separately. The
hypersensitive cultivar Anza responded in the same way to inoculation with M. graminicola regardeless
or whether or not P. striiformis was present. Data from field plots inoculated with M. graminicola and
naturally infected with P. striiformis confirmed data obtained in the glasshouse and growth chamber. A
smaller amount of leaf area was damaged by P. striiformis when both pathogens were present than
when this pathogen was present alone. Caution is needed in reading plants for stripe rust if septoria
tritici blotch is present.
Wheat leaves infected by P. striiformis remained green longer and were heavier than leaves infected by
both pathogens. This may have been due to the sequestering effect known to be characteristic of rusts.
It is possible than M. graminicola interferred with the redirection of translocation of assimilates that is
a usual effect of rust. INTERACTIONS OF
STRIIFORMIS AND
MYpOSPHAERELLA
ON WHEAT
by
Ri c ar d o Burrows Madar i aga
A th esis submitted in p a r tia l fu lfillm e n t
of the req u ire m e n ts
f o r the degree
of
Master of Science
in
Plant
Pathology
MONTANA STATE UNIVERSITY
Bozeman, Montana
Ma r c h 1984
«
MAIN LIB.
-Ii-
cop
APPROVAL
of
a thesis
submitted
by
Ricardo
Patricio
M a d a r i a g a Burrows
T h i s t h e s i s h a s b e e n r e a d by e a c h m e m b e r o f t h e
th e sis committee
a n d h a s b e e n f o u n d t o be s a t i s f a c t o r y
regarding
content,
English
usage,
format, citation,
b i b l i o g r a p h i c s t y l e , and c o n s i s t e n c y , and i s r e a d y f o r
s u b m i s s i o n to the College of Graduate S t u d i e s .
Da t e
Chairperson,Graduate
Approved f o r
the
Maj or D e p a r t me n t
Da t e
Approved f o r
Dat e
the
College
of Graduate
Studies
Commi t e e
-iiiSTATEMENT OF PERMISSION TO USE
In
presenting
this
thesis
in
partial
fulfillment
of
the re q u ire m e n ts for a m a ster's
degree at Montana S t a t e
U niversity,
I
library
available
borrowers
to
quotations
from t h i s
permission,
source
is
agree
that
under
thesis
provided
professor,
the
accurate
or
extensive
thesis
in
his
Libraries
when, in
the
use of
the
material
is
or
of
ma k e
Library.
without
it
Brief
special
acknowledgment
the
material
ma y be g r a n t e d
absence,
opinion
for
in
quotation
by
of e i t h e r ,
scholarly
this
the
thesis
of
or
by my m a j o r
D irector
the
purpose.
for
from
of
proposed
Any c o p y i n g
financial
n o t be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n .
Signature.
Da t e
of
are allowable
that
for
re p r o d u c tio n of t h i s
shall
rules
shall
ma d e .
Perm ission
use
the
gain
V
-
ACKNOWLEDGMENT
I
wish
to
contribution
acknowledge
of the
and e x p r e s s
following
throughout
this
The
M athre,
their
time
W.
in
My
L.
C.
the
fellow
National
degree
possible.
giving
And s p e c i a l l y
( IN I A-
my a b s e n c e
my
from
thesis
and
professor
com m ittee,
and
Dr .
D.
C.
Dr.
D.
E.
Sands,
for
assistance
and
advice.
Yahyaoui
graduate
Th e
for
patience
s e r v i n g a s my m a j o r
w r i t i n g of t h i s
and c l a s s
(INIA)
friendship,
Alexander,
Mor k
research
Station
of
and i n v a l u a b l e
Colleen
the
study.
members
Dr.
patience
guidance while
for
people:
D r . A. L . S c h a r e n , f o r h i s
professional
my t h a n k s
for
her
thesis.
students
who
supported
my
work w i t h e n t h u s i a s m .
Institute
me
to
my
of
Agricultural
scholarship
my f r i e n d s
from
that
Research
made
this
Quilamapu Research
C h i l i a n ) wh o t o o k c a r e o f my w o r k d u r i n g
the
country.
- v i TABLE OF CONTENTS
Pa ge
TITLE PAGE............................................................................................................
APPROVAL PAGE....................................
ii
STATEMENT OF PERMISSION TO U S E . ..................................................
iii
VI T A..............................................................
ACKNOWLEDGMENTS. . . .
iv
......................................................
v
TABLE OF CONTENTS.................................................................................
LI ST OF TABLES....................................................
i
vi
viii
A B S T R A C T ...................... .................................................................................
i x
INTRODUCTION....................................................................
I
REVIEW OF LI TERATURE.........................................................
5
Septoria
b l o t c h ....................................................... .. . .
5
T a x o n o m y ............................................................................................
E n v i r o n m e n t a n d i n f e c t i o n p r o c e s s ...........................
5
6
Stripe
tritici
r u s t ............................................................................................... 17
T a x o n o m y ............................................................................................
E n v i r o n m e n t a n d i n f e c t i o n p r o c e s s ...........................
17
17
I n t e r a c t i o n ............................................................................................... 27
MATERIALS AND ME T H O D S . . . ....................................................................... 32
G e n e r a l p r o c e d u r e s .................................................
S p e c i f i c p r o c e d u r e s . . . . . ..........................................................
I n t e r a c t i o n e x p e r i m e n t A..................................................
I n t e r a c t i o n e x p e r i m e n t B . . . . ........................................
32
34
34
36
-viiTABLE OF CONTENTS ( c o n t i n u e d )
Pa ge
I n t e r a c t i o n a t g e r m i n a t i o n l e v e l ..................................... 37
F i e l d o b s e r v a t i o n s .......................................................................... 37
RESULTS................................................................................................
I n t e r a c t i o n ............................................................................................
E x p e r i m e n t A...............................................
E x p e r i m e n t B ..................................................................................
G e r m i n a t i o n ......................................................................... ..
Field
39
39
39
48
62
o b s e r v a t i o n s .......................................................................... 62
DI SCUSSI ON............................. .............................................................................
67
CONCLUSIONS......................................................................................................... 76
LI TERATURE............................................................................................................ 7 8
APPENDIX
87
-viiiL I S T OF TABLES
Pa ge
Table
I
Plant s p e c i e s r e p o r te d as s u s c e p t i b l e
S e o t o r i a t r i t i c i Rob. e x . De s m .
Table
2
E f f e c t o f t e m p e r a t u r e o n Mv c o s o h a e r e l l a
graminicola development.
13
Table
3
Hosts a tta c k e d
in California.
I9
Table
4
E f f e c t o f t e m p e r a t u r e on JEj . s t r i i f o r m i s
West, as r e p o r t e d i n t h e l i t e r a t u r e .
21
Table
5
Microorganism i n te r a c t io n s occurring in
Z r i l i & u m ES- S- Hz um. r e p o r t e d
in
the
literature.
28
Table
6
Percentage of
c o e ffic ie n ts
c u ltiv a r s
i
s t r i i f ormis in
Mvcosohaerella
leaf
area
affected
and
of i n f e c t i o n of fiv e
n fe c te d
byZPL£^iaia
the p r e s e n c e or a b se n c e of
graminicola.
40
Table
7
P e rc e n ta g e of p l a n t s in each P u c c in ia
s t r i i f o r mis i n f e c t i o n type i n o c u l a t e d
alone
or in
com bination
with
Mvcosohaerella g ra m in ic o la .
43
Table
8
P ercen tag e of
leaf area affected
by
sr.aaiiiis.fi.la, i n t h e
absence
of
Zllfifiifiia
45
Ratio
of p la n ts b e arin g p y cn id ia
of
MZ f i f i f i f i h f i f i f i f i l l a S f i a a i f i i f i f i l f i t o t o t a l
p l a n t s i n t h e p r e s e n c e and a b s e n c e of
Puccinia styiijformis
47
presence
or
striiform is.
Table
9
by £_*. s t r l i f o r m i s
to
West,
7
-ixLI ST OF TABLES ( c o n t i n u e d )
PAGE
,
;
Table
10
E f f e c t of d i f f e r e n t inoculum com binations
of Mz&aa&ka&rAlla sr& a in i& fila . and
a l r i i f a r m i a on n o n g r e e n a r e a ,
r u s t s e v e r i t y and l e a f dry
weight
of
c u l t i v a r Lakhish.
Table
II
E f f e c t of d i f f e r e n t inoculum c o m b in a ti o n s
of
snam iai^ojia
and
£ uj£ C i n i a
S-IlLiiZnzffiis.
on l e a f
area
a f f e c t e d and p y c n i d i a produced
by M.
K r a m i n i c o l a on L a k h i s h .
51
Table
12
E f f e c t of d i f f e r e n t inoculum com binations
o f Mx_e.fi:s a k a ^ r s - l l s . x n s a i P i f i f i l a a n d
P U-C-Ci ni a s t r i i f o r m i s o n n o n g r e e n a r e a ,
r u s t s e v e r i t y and l e a f dry
weight
of
c u l t i v a r Anz a .
53
Table
13
E f f e c t of d i f f e r e n t inoculum c o m b i n a t i o n s
o f MxfifififikafiPfilla a r a m l f i i f i f i l a a n d
Zfififiiala fikfiiiffifirnifi
on
leaf
area
a f f e c t e d a n d p y c n i d i a p r o d u c e d by M.
a r a m i n i c o l a on c u l t i v e r Anza.
55
Table
14
E f f e c t of d i f f e r e n t inoculum combinations
of
Mxfifififikafififilla Sfiamifiififila and
P u c c i n i a s t r i i f o r m i s on n o n g r e e n a r e a ,
r u s t s e v e r i t y and l e a f dry
weight
of
c u l t i v a r Lemhi .
57
Table
15
E f f e c t of d i f f e r e n t inoculum c o m b i n a t i o n s
o f M x f i f i f i f i k a f i f i f i l l a Sfiamlfiififila a n d
Zfififiifiia fiifiiiffifim ifi
on l e a f
area
a f f e c t e d and p y c n i d i a produced
by M.
K r a m i n l c o l a on c u l t i v a r L e m h i ,
58
Table
16
E f f e c t of d i f f e r e n t inoculum combinations
of
Mx f i f i f i f i & f i f i f i f i l l f i Sfiamifiififila a n d
P u c c i n i a s t r i i f o r mi s o n n o n g r e e n a r e a ,
r u s t s e v e r i t y and l e a f dry
weight
of
c u ltiv a r Baart.
60
-X -
L I S T OF TABLES ( c o n t i n u e d )
PAGE
Table
17
E f f e c t of d i f f e r e n t inoculum combinations
of
azaaiaiaala
and
f iijs .js .ia ia a i r i i f o a m i a
on
leaf
area
affected
a n d p y c n i d i a p r o d u c e d by M.
g r a m i n i c o l a on c u l t i v a r B a a r t .
61
Table
18
Mean a n d r a n g e o f p e r c e n t a g e o f l e a f a r e a
a f f e c t e d by Z t i a a i a i a a t i a i i f a a m i a a n d
M y C O S D h a a r e i l a a r a m i a i a a l a o n 84 w i n t e r
w h e a t c u l t i v a r s . B o z e ma n 1983*
64
Table
19
Me a n a n d r a n g e o f p e r c e n t a g e o f l e a f a r e
a f f e c t e d by Z t i a a i a i a t i t r i i i t i n m i s a n d
M x a a a a h a a a a i i a s a a a i a i a a i a o n 83 s p r i n g
. w h e a t c u l t i v a r s . B o z e ma n 1983*
65
T a b l e 20
Increase
i n l e a f w e i g h t e x p r e s s e d as
p e r c e n t a g e o f t h e c o n t r o l ( 00 00) i n d u c e d
by
the
pathogens
M Xatititikaaae i I a
g r a m i n i c o l a (S) a n d Zt i t i t i i t i i a s t r i i f o r m i s
(R) i n f o u r s p r i n g w h e a t c u l t i v a r s .
87 '
T a b l e 21
A n a l y s i s of v a r i a n c e and o r t h o g o n a l
co m p ariso n s of p e r c e n t g e r m in a tio n of
P u c c i n i a s t r i i f o r m i s u r e d o s o o r e s t e s t e d on
p o l y e t h y l e n e membranes.
88
-xiABSTRACT
P u c c i n i a s t r i i f o r m i s and M v o o s o h a e r e l l a g r a m i n i c o l a
a r e f r e q u e n t l y f o u n d a t t a c k i n g t h e s a m e w h e a t l e a f . The
e f f e c t o f one p a t h o g e n u p o n t h e o t h e r , a n d t h e e f f e c t s o f
t h e i n t e r a c t i o n s b e t w e e n p a t h o g e n s upon t h e h o s t - p a t h o g e n
i n t e r a c t i o n s are the s u b je c ts of these stu d ies.
Seedlings
of four s p rin g wheat
cultivars
were
inoculated
at
different
time
com binations
of P.
s t r i i f o r m i s a n d JGL_ g r a m i n i c o l a . I n s u s c e p t i b l e c u l t i v a r s ,
i n o c u l a t i o n s w ith both pathogens r e s u l t e d in s i m i l a r host
t i s s u e d a ma g e t o t h e d a ma g e o b t a i n e d by i n o c u l a t i o n w i t h
e a c h o r g a n i s m s e p a r a t e l y . The h y p e r s e n s i t i v e c u l t i v a r
A n z a r e s p o n d e d i n t h e s a m e w a y t o i n o c u l a t i o n w i t h M.
g r a m i n i c o l a r e g a r d e l e s s o r w h e t h e r o r n o t JLt s t r i i f o r m i s
was p r e s e n t .
D a t a f r o m f i e l d p l o t s i n o c u l a t e d w i t h M.
g r a mi n i c o l a a n d n a t u r a l l y i n f e c t e d w i t h P . s t r i i f o r m i s
c o n f i r m e d d a t a o b t a i n e d i n th e g l a s s h o u s e and gro w th
c h a m b e r . A s m a l l e r a m o u n t o f l e a f a r e a w a s d a m a g e d by P.
s t r i i f o r m i s when b o t h p a t h o g e n s w e re p r e s e n t t h a n when
t h i s p a t h o g e n was p r e s e n t a l o n e . C a u t i o n i s n e e d e d i n
reading plants for s trip e rust i f septoria t r i t i c i blotch
is present.
W h e a t l e a v e s i n f e c t e d by JL_ s t r i i f o r m i s r e m a i n e d
g r e e n l o n g e r a n d w e r e h e a v i e r t h a n l e a v e s i n f e c t e d by
both
pathogens.
This
may h a v e
been due to th e
s e q u e s t e r i n g e f f e c t k n o wn t o be c h a r a c t e r i s t i c o f r u s t s .
I t i s p o s s i b l e t h a n M. g r a mi n i c o l a i n t e r f e r r e d w i t h t h e
r e d i r e c t i o n of t r a n s l o c a t i o n of a s s i m i l a t e s t h a t i s a
usual e f f e c t of r u s t .
I
INTRODUCTION
"For
study
good
the
world,
reason,
effect
the
exception
of
research
one
occurrence
rather
disease
of
than
pathologists
one
the
at
a time.
disease
rulg."
at
tend
In
the
a time
( Zadoks
and
to
real
is
the
Schein,
1979) .
Several
in
wheat,
blotch
rust
such
by
and
(1970);
disease
as
interaction
root
Bensaude
glume
B rokenshire
disease
(1926),
blotch
and s e p t o r i a
rot
by
and
The
have
and
Sprague
Hy d e
tritici
(1974).
systems
(1978)
blotch
been
noted
speckled
leaf
(1950);
and
Va n
stripe
der
Wa l
a n d p o w d e r y m i l d e w by
presence
of
more
than
one
p a t h o g e n a t t h e s a m e t i m e on t h e s a m e l e a f c a n be s e e n a s
having a d d itiv e
or
less,
or more damage to t h e h o s t , as compared
to
the
the
same,
effect
effect
of each
can
be
epidemiological
The
synergistic
leaf
pathogen a c tin g
measured
behavior
tissue
modified.
Consequently,
infection
is
(1981),
different
discussing
n o d o r u m and
effects
the
of
as
yield
each
from
by
substrate
the
separately.
loss
or
in
This
in
the
pathogen.
colonized
the
which r e s u l t
one
for
original
interaction
P u c c i n i a s t r i i f o r mi s ,
pathogen
a
secondary
tissue.
between
reported
is
Hy d e
S s.E -t.azlS ,
that
areas
2
first
attacked
suitable
for
by
S jl
n o d o r um
infection
•
by
are
the
probably
obligate
Furtherm ore,
areas
s t r i i f o r m i s ma y p o s s i b l y
be i n f e c t e d
such
the
double
infection
of
same
no
longer
parasite,
attacked
by
by
JLt
n o d o ru m but
tissue
has
not
been
pathogens are
like
re corded.
Yar wood
(1959),
other
factors
which
can
unrelated
is
Northwest
its
reported
up t o
of
of
in
to
According
VII
1 955 r e s u l t e d
diseases,
infection
epidemic
Shipton
in
the
of
damage
by s e c o n d a r y
wheat
in
the
et
importance
USA.
In
range
from
to
has
This
throughout
is
the
JJj . a l r i i f o r m i s .
commercial
in
to the
loss
economic
(1971),
fields,
20 t o 75 p e r c e n t .
Utah and
Doodson e t
an e s t i m a t e d
al.
which
literature.
which o c c u r r e d
in addition
to
diseases
C a l i f o r n i a , Montana,
rust
Referring
to
mechanical
i n I 9 6 0 a n d 1961 i n t h e P a c i f i c
the
estimated
40%.
or
reported
proportions
losses
20 p e r c e n t ,
the
economic
stripe
in
plants
(1967)
Region
were
plant
chemicals
attention
Hendrix
epiphytotic
of
one
by
that
pathogens.
muc h
explained
losses
as
predispose
Rust
world.
such
plant
received
stated
in
al.
yield
Wyomi ng
(1964),
Holland
loss
He
the
on H e i n e s
of
15 t o
of q u a lity .
importance
noted
that
of
Septoria
few
critical
3
studies
have
been
attributable
nodorum
conducted
to
establish
t o t h e m . The s a m e a u t h o r e s t i m a t e d
together
w i t h £-«- t r i t i c i
were
to a ten p e rc e n t y i e l d lo s s in f i f t y
belt
the
responsible
losses
that
S.
for
up
p ercent of the wheat
o f W e s t e r n A u s t r a l i a i n 1 966 . I n a u t u m n s o w n c r o p s
i n t h e C a n t e r b u r y p r o v i n c e o f New Z e a l a n d , r e d u c t i o n
in
yield
S.
of
tritici
up
by
to
wheat
the
disease
et
with
characteristics
other
of
disease
directed
and
for
occurrence
of
the
toward
it
as
"a
major
p a r t i c u l a r l y on
America,
in
the
,
in
attack
cereals,
is
Th e c o o l e n v i r o n m e n t a l
intermountain
stripe
of t h e s e
description
are
of
have s i m i l a r i t i e s
and
this
coincidence
two d i s e a s e s t o g e t h e r i n
in
improvement
introduction
regions
rust
by Mor k ( 1 9 8 2 ) ,
genetic
c a u s e d by S.
Z j.
that
requires
as r e p o r te d
to
Australia".
d e v e l o p m e n t . Th e
those
Most
losses
South
that
rusts
coastal
conditions
field
in
temperatures.
favorable
the
attributed
reported
and i n
noted
for
the
coast,
Africa,
favorable
explains
heavy
(1980),
sea
(1971),
adapted to lower
to
been
i n many p a r t s o f t h e w o r l d ,
of East
comparison
reported
a l.
M editerranean
Volin
has
(1978).
countries
Bahat
highlands
percent
Sanderson
Several
t r it i ci.
40
of
Oregon.
of
cultivars
resistance
to
is
one
4
pathogen
at
cultivars
must
pathogens
in
a
show
order
The a i m o f
of
tim e.
presence
wheat.
of
in
simultaneous
to
this
My c o s p h a e r e l l a
However,
was
g r a mi n i o o l a
to
in
and
its
to
ma n y
potentials.
study
with
s t r i i fo rmis
conditions
resistances
m aintain high y ie ld
research
Puccinia
field
the
behavior
without
common
the
host,
5
REVIEW OF LITERATURE
Septoria
tritici
blotch
Ta xonomy
Speckled
leaf
blotch,
leaf
spot
or
nebular
common n a m e s w h i c h h a v e b e e n u s e d t o d e s c r i b e
caused
was
by S e p t o r i a
coined
colored
by
tritici
Weber
Rob.
(1922).
He
There
was
an
w o r k s h o p i n B o z e ma n ,
to r e f e r
to the
blotch
Montana
common name o f
( An o n y mo u s
1983).
d e u t e r o m y c e t e s - a n a m o r ph s t a t e
Rob.
The
with
to
the
name
"dark
able
telomorph
to
of
the
at
Septoria
(August 2 - 4 ,
disease
Correct
the
the
as
1 983)
septoria
citation
pathogen i s
of the
Septoria
e x Des m.
Sanderson i s o l a t e d
was
disease
The f i r s t
referred
agreement
diseases
tritici
De Sm.
the
are
and p r o m i n e n t " p y c n i d i a whi ch pr oduced a s p e c k l e d
appearance.
tritici
ex.
spot
was
it
reproduce
ascospores
born
not
from
described
New Z e a l a n d w h e a t
symptoms
in
until
of
this
pseudothecia.
I 97 2 w h e n
stubble
disease
The
and
starting
two
celled
a s c o s p o r e s u s e d m e a s u r e d 10 t o 15 x 2 . 5 t o 3 m i l l i m i c r o n s
and
were
(Sanderson,
referable
1972).
telomorph stage is
Schroeter.
to
Correct
the
genus
citation
MycosphaerellA
of
M ycosphaerella
this
Ascomycetes-,
(Fuckel)
6
E n v i r onment and i n f e c t i o n p r o c e s s
Overseasoning
A f t e r c r o p h a r v e s t S. t r i t i c i
in
the
stubble
conditions
which,
discharge
of
for
a
in
time,
depending
on
a wet e n v i r o n m e n t ,
of p y c n i d i o s p o re s.
volunteer
inoculum w ill
wheat
or
will
Th e s p o r e s ,
other
the
moisture
cause
in the
susceptible
remain
total
absence
species,
will
die.
The
hypothesis
s p e c i e s has been
most
has
of
the
been
of
broadened
by
ascospores
released
are
the
the
last
of
six
of
tritici
to
(Table
after
inoculum fo r
of
the
the
next
plant
species
without
further
in
Hampton
(1978),
New Z e a l a n d
Therefore
allow
summer and t o
crop.
However,
im plications
and
harvest.
that
plant
of
a
I).
EL_ g r a m i n i c o l a
main s t r u c t u r e s
part
inoculation
Sanderson
weeks
other
authors.
on o t h e r
epidem iological
range
According
attacking
by s e v e r a l
artificial
the
host
Septoria
studied
testing
done
studies
of
the
first
pseudothecia
fungus
produce
are
the
to
the
survive
primary
7
Table
I .
Plant sp ec ie s re p o rte d as
S e o t o r i a t r i t i c i Rob. ex.
P la n t s p e c ie s
Agropvron reo en s
A g ro s tis te n u is
A rrenatherum e l a t i o r
Bromus m o llis
Bromus s t e r i l i s
D a c tv lis glo m erata
F e stu c a aru n d in a ce a e
H olcus la n a tu s
Hordeum murinum
Hordeum v u lg a r is
Poa annua
Poa o r a t e n s i s
Poa secunda
Poa t r i v i a l i s
S e c ale e e r e a le
S t e l l a r i a media ^
V uloia brom oides
susceptible
Desm.
A uthor
T eterev n ik o v a and Bokhyan (1970)
W illiam s and Jo n es (1973) •
D erevyankin ( 1969) .
B ro k en sh ire (1 9 7 5 ).
W illiam s and Jo n es (1 9 7 3 )-h .
W illiam s and Jo n es £ J9 7 3 )- b.
Z aprom etoff (1926)
B ro k en sh ire (1 9 7 5 ).
W illiam s and Jo n es ( 1973) .
B ro k en sh ire ( 1975) .
B ro k e n sh ire ( 1975) .
B ro k en sh ire (1 9 7 5 ).
W illia m s and Jo n es (1 9 7 3 )-b .
B r o k e n s h ir e ( 1975) ,
Weber (1922), W illia m s and Jo n es
(1 9 7 3 ).
Sprague ( 1944) . '
W illiam s and Jo n es (1973)•
D erevyankin ( 1969) .
S p rag u e and F is c h e r (1952)^ , Weber
( 1922 ) .
P r e s te s ( 1976) .
B ro k en sh ire (1 9 7 5 ).
1 / Only non Gramineae (C a ry o p h y lla c e a e ).
2 / As c ite d by P r e s te s (1976)'.
to
8
Dissemination
Natural
dissemination
Bahat
et
infection
al.
of the anamorphstate
(1980),
cycle,
from
d isp ersa l, penetration,
pycnidial
and
Shearer
most
that
Removal
and S m i t h
of
the
of
of
(1978),
of
the
liberation,
development
Station
in
severity
of
in
rainfall
variation
in
from
found t h a t
at
the
Temora
through
the
responsible
sporulation
of
the
reduced
to
model
the
for
tritici.
the
13 p e r c e n t . M u r r a y a n d
amount of r a i n
A ustralian
gave
was
regression,
in
September
Agricultural
Research
highest
correlation
with
tritici.
Scharen
( 1 966 ) r e p o r t e d
n o d o r u m c o mme n c e d
soon
and
three
continued
for
cessation
situation
using multiple
determ ination
(1978),
October
until
stages
pycnidiospore
and l e s i o n
rain fall
coefficient
and
all
de w.
variation
(75%)
Martin
that
f o r m a t i o n a r e d e p e n d e n t on m o i s t u r e i n th e , f o r m
of r a i n f a l l
found
noted
was
after
six
observed
formation,
extrusion
until
the
to
with
then
seven
jL_
moisture
pycnidia
s p o r e e x u d a t i o n o f Sj .
wetting
hours,
after
pycnidia
that
were
of
leaves
or
straw
steadily
diminished
hours.
A sim ilar
tr i t iel
induced
depleted.
where
after
pycnidiospore
(Eyal,
1 971) •
9
According
disseminated
while
to
Shipton
et
al.
(1971)»
1L. n o d o r um i s
by s e e d - b o r n e p y c n i d i a a n d p y c n i d i o s p o r e s
seed-borne
inoculum
has
not
b e e n d e m o n s t r a t e d i n S.
tritic i.
A rtificial
dissemination
It is
of
possible
5_=_ t r i t i c i
pycnidia
by
to
spreading
containing
spread
prepared in
anamornh s t a t e
t o i n d u c e 1a n a r t i f i c i a l
viable
see d lin g emergence.
used
of the
wheat
synthetic
potato
strained
to
10 6
also
dextrose
through
spores
u s e d I O6
and Mer kl e
Natural
artificially
agar.
The
layers
of
m illiliter.
is
of
the
used 6 x 1
most
the
and as c o s p o r e
inoculum
dishes
suspension
Jenkins
and
(1981),
per m i l l i l i t e r .
spores
was
diluted
and J o n e s
Gough
per m i l l i l i t e r .
telomorph s t a t e
differences
dissem ination
currents.
t i m e was s u f f i c i e n t
between
is
Even i n
S a n d e r s o n and Hampton (1978)
during night
use
cheesecloth
important
c a n be mo v e d by a i r
of r a i n ,
to
from p e t r i
spore
a n d 5 x I O6 s p o r e s
(1977),
pycnidiospore
water
per
after
m e d i a a s w a s r e p o r t e d by S h a n e r a n d
dissem ination of
One
latter
two
just
with
I 980). A nothe r method
Finney (1982). Gonidia were c o l l e c t e d
of
infested
pycnidiospores,
( Bahat et a l.
inoculum
straw
epiphytotic
found
that
the
the
absence
that
to induce
free
spore
release.
The s a me a u t h o r s
noted
that
as cospores
as e f f i c i e n t
in o cu lu m of s e p t o r i a
tritici
months
harvest,
were
after
releasing
that
spores.
wind-borne
pseudothecia
Sanderson
and
ascospores
crops
growing at a d istan ce
wheat
stubble.
G e r m i n a t i o n and l a t e n t
Pycnidiospores
blotch. Eight
still
Ha mpt on
initiated
can s e r v e
capable
(1978)
concluded
infections
of s e v e r a l
of
on young
kilom eters
from
period
and
ascospores
of
g r a mi n i c o l a
g e r m i n a t e w e l l i n w a t e r . H o w e v e r , t h e r e i s no r e f e r e n c e
in
the
lite ra tu re
humidity,
to
the
which
temperature
latent
period
noted th a t la b o rato ry
model
that
the f i e l d
for
b e 11 t o
15 d a y s
that
22
C,
this
the
spore
tritici
Shaner
disease
to
or
(1976)
support
a
progress in
blotch.
the
shortest
May a n d J u n e .
lesions
to
variables
germination
pathogen.
weather
reported
in
to
the
da ta were i n s u f f i c i e n t
septoria
(1922),
light
of
would r e l a t e
We b e r
at
and
correlates
and
latent
Fellows
first
period to
( I 96 2)
fruiting
noted
bodies
a p p e a r e d a f t e r 21 t o 3 O d a y s . H o l m e s a n d C o l h o u n ( 1 97 5 ) ,
suggested
that
under w in te r
Shearer
period
in
the l a t e n t
p e r i o d w a s a s l o n g a s 60 d a y s
conditions.
and
Zadoks
(1972),
studying
nodorum. found t h a t , a p a r t
from
the
the
latent
variance
between the f i r s t
appearances
of s p o r u la tin g
pycnidia,
t h e r e was a l s o a v a r i a n c e w i t h i n l e a v e s w i t h r e s p e c t to
appearance
work
of
they
successive
noted,
"T h ese
variances
neglected...";
however,
complications
encountered
Germination,
determined
Ha u ( 1 9 8 1 ) ,
found t h a t
the
period
expression
not
been
of
wetting
of
and
these
be a c c o u n t e d
their
conveniently
of l a t e n t
latent
period
are
temperature
but which
phenomena.
Aust and
of the v a r i a b i l i t y
be e x p l a i n e d
by i n o c u l u m d e n s i t y ,
The
the
periods.
understood
nodorum could
periods.
In
demonstrated
study
45 p e r c e n t
t e m p e r a t u r e , 12 p e r c e n t
could
in the
which are not w e ll
the
by
have
point
penetration
can m odify
percent
this
pycnidia.
by t h e i n t e r a c t i o n o f h u m i d i t y ,
and o t h e r f a c t o r s
latent
sporulating
remaining
in
by
and o n ly 3
40
percent
for.
Environment
Light
Benedict
intensity
(1971)
studying
on Kt g r ami n i c o l a
the
effect
infection
in
of
light
w h e a t, found
t h a t b e t w e e n 500 a n d 4000 l u x g a v e c o n d i t i o n s f a v o r a b l e
for
pycnidia
form ation
than
other
m agnitudes
of
illum ination.
Intensities
b e tw e e n 3,000 and 8,000 lu x
were
for
growth
optim al
substomatal
chamber.
early
Eight
of
thousand to
hyphae
in
the
15,000 l u x i n d u c e d
12
faster
conidial
to
a lower
of
20 , 0 0 0
24,000
bright
range
to
,lux.
20 p e r c e n t
day a t
sea
but
and
penetration
as. c o mp a r e d
o f 500 t o 4 , 0 0 0 l u x a nd a h i g h e r r a n g e
24,000
lux is
very low,
germination
According
Shaner
( 1976),
o f t h e ma x i mu m i l l u m i n a t i o n on a
level,
definite
to
meaning
requirement
that
the
fungus
for
light
has
a
intensity.
Humidity
Ma n y a u t h o r s
the
most
im portant
development
of
S.
spore
germination
other
leaf
four
to
that
and f o r
mycelial
spread
dew
disease
postinoculation
which t h e r e
moisture
the
for
pathogen
to
leaf
also
seems
be
the
(1956),
to
tissue
used
obtain
reported
a fte r
necessary
this
period
period
is
governing
of
within
(1983)
s e e m s t o be
factor
water
Hilu
Hess and Sh an er
of
moisture
spread
Soaking of
day p o s t i n o c u l a t i o n
sev erity
Free
the
communication).
symptoms.
high
environm ental
t r i t i ci.
tissues.
important
personal
agree
a
(Eyal,
three
to
5^. t r i t i c i
increases
increases
until
to
in
in
the
up t o 72 h r s , a f t e r
w a s no e f f e c t .
Temperature
According to Hilu
S.
tritici
of
seven
is
to
(1956),
temperature
16 d a y s ,
the in cu b atio n
dependent
being longer
at
and
p e r i o d of
can have
lower
a range
temperatures.
13
In sum m ary, the i n f o r m a t i o n r e l a t i n g
and t e m p e r a t u r e
present
T a b l e 2. B a h a t e t
a I . (1980),
in
pathogen
temperature
the
development
dependent.
relationship
temperature
Table
during the
3
C
the
£_«_
However,
wheat
M. g r a m i n i c o l a
literature
noted
of
between
2 . E f f e c t of
graminicola
Tem perature
in
to
that
disease
are
on
phases
probably
information
developm ent
growing season i s
temperature
development,
shown i n
certain
tritic i
specific
is
on
and
lacking.
Mv c o s p h a e r e l l a
O ccurrence o f f e a tu r e
Minimum te m p e ra tu re f o r c o n id ia g e m in a tio n
Weber (1922) and G eo rg h ies (1 9 7 4 ).
Two c o n s e c u tiv e d a y s a t t h i s t e m p e r a t u r e
in h i b i t e d i n f e c t i o n R ehfro and Young (1 9 5 6 ).
I n f e c tio n fa v o re d M oralqs (1957).
as c ite d by S h ip to n e t a l . , 1971).
D isease developm ent proceeded e q u a lly
w e ll M o ra le s ( 1957) a s c i t e d by
S h ip to n e t a l . , 1971).
Optimum te m p e ra tu re f o r in f e c tio n
Fellow s (I 962!) an d R e n f r o a nd Young (1 9 5 6 ).
F a v o r e d c o n i d i a g e rm in a tio n
(W eber, 1922).
I n f e c t i o n g r e a t l y reduced.
(Narvaez,
1 9 5 7 ) a s c i t e d by
S h a n e r, 1976 ).
Maximum te m p e ra tu re f o r c o n id ia g e rm in a tio n
(W eber, 1922) and (G e o rg h ie s, 19 74).
7
16-21
16-27
21
22-24
27
33-37
Penetration
Weber
cuticle
(1922)
found
that
at a point d ire c tly
epidermal
germ
tubes
penetrated
above a d j a c e n t
c e l l s , suggesting that
walls
the
of the
t h e r e wa s s o me e v i d e n c e
of stoinatal i n f e c t i o n ;
rare
be
and my c e l i u m
directly
However,
Hilu
(1956)
( 1 979)
or
appressoria.
narrower
was
5^.
the
of
found to
septoria.
fungus
Direct
penetration
noted
appressorium
adjacent
epidermal
or
open or
without
that
usually
both
and
penetrate
formation
also
subsequent
by
closed
occasionally.
the
was
production
walls,
only
nodorum could
with
penetration
either
that
observed
that
followed
through
not
pycnidiospores
stomata
(1978)
germ ination,
to
s t o m a t a were
were q u i t e
the opened or c l o s e d s t o m a t a and t h a t
found
open
the
reported
penetration
Straley
closed
entering
connected
penetrated either
direct
however, such i n s t a n c e s
of
observed,
to
spore
septorioid
fungi
above the j u n c t i o n of
also
reported
penetration
stomata.
A s s e s s i n g o f s y mp t o ms a n d s i g n s
According
to
Khan
(1978),
three
t e c h n i q u e s were noted i n the l i t e r a t u r e
S. t r i t i ci:
CIMMYT
scale;
I)
The
foliar
Information
a n d 3)
of
narrower.
Eyal
percentage
Septoria
Bulletin
a scale
A diagram
this
scale
et
to
progression
disease
commonly
for assessment
scoring
Number
used
38;
scale
2)
of
of the
R osielle's
of p e r c e n t a g e l e a f a r e a a f f e c t e d .
percentage
scale
al.
compiled
(1983)
assess
head
coefficient.
and
This
was
made
a
leaf
scale
by
K.M.
diagramatic
coverage,
rates
a
plant
and
disease
scale
height
to estim ate
square
related
by s e p t o r i a
Percent
millimeter
(1980),
by
were
Shaner
as
covered
green
plant
symptoms
symptoms
in
the
on
of
mature
field,
Physiology of the
According
penetrates
and
Rufti
to
plant
and
et
that
the
in
a
(1978),
of
colonized
occurs
in
the
to
pycnidial
substomatal
height
be f o u n d on
to
n o d o r u m grown
and
adult
( r ^ =0 . 6 4
after
growth
necrosis
prior
leaf
plant
E< 0 . 0 1 ) .
plant
subsequent
that,
each
maximum
with
correlated
hyphal
of
disease
chamber
characterized
zone
al.
growth
is
the
et
-comparing
response
of
per
(1980),
tissue
advance
of
of
could
seedling
narrower
tissue,
Bahat
area
al.
infected
diseased
area
density
estim ation
green
grown
highly
leaf
21 d a y s a f t e r
(I 9 8 2 ) .
tritic i
plants
were
of
of
found
susceptibility
by
pycnidia
seedlings
to
estimated
Finney
percentage
tissue.
scale
a r e a and p y c n i d i a l
visually
(cm) a t w h i c h p y c n i d i a
Eyal-Brown
blotch.
and
by S-t. t r i t i c i
the
d e n s i t i e s and t h e C l i v e James
t r i t ici
the
of
a percentage
leaf
assessed
severity
composed
tritici
necrotic
inoculation
is
pycnidial
s c a l e , which a l s o
covered
and
is
colonization.
cavities
intercellular
by c h l o r o s i s
tissue
production,
in itia l
and
as
well
as
He
also
noted
hyphal
of n e c r o t i c
an
aggregation
tissues.
16
Malcolm
( 1979),
reported
that
the
infection
process
interferes
with
both
photosynthesis,
either
in
the
contention,
which
concluded
plant
must
he i s o l a t e d
caused
in wheat.
and
symptoms
affect
The t o x i n ( s ) , b e c a u s e
galactose
because
to
it
failed
pass
u ltr a filte r
or
identified
a glycopeptide.
as
According
little
upon
to
to
be e x p l a i n e d
if
tissue
by
caused
intercellular
Malcolm
plant
cell
the
walls.
toxin
Ride
penetration
(1981)
and i n
mor e r e s i s t a n t
effective.
cyclohexam ide,
application
of
culture
septoria
disease
rich
serine,
a
and
D iaflo
membrane,
this
protoplasts,
The d e a t h
toxin
while
of the
involved
in
hyphal
reported
pentose
either
(1978),
Fungal
in
cell
that
the
i
this
broth
dialysis
the ra te
noted
a
a
of
was
acts
causing
cells
may
necrotic
growth in
the
penetration.
lignification
g r o w t h o f £L. n o d o r u ro by r e d u c t i o n
cultivars
They
was
can oc cu r w i t h o u t
probably reduced fungal
in
of
through
is
tritici.
spaces
and
c e ll
To s u p p o r t
from
it
and
disruption
and a m e th y l
standard
the
damage
Bird
a
the
characteristic
t r l tld i
translocation
yield.
a toxin(s)
th re o n in e , glucose,
directly
that
Sj .
of fungal
lignification
that
the
translation
ultraviolet
light
colonization.
may be e v e n mo r e
adm inistration
inhibitor,
to
In
unwounded
or
of
the
leaves
V
17
prior
all
to
inoculation,
varieties
reduced v a r i e t a l
more s u s c e p t i b l e .
differences
making
This su g g ests t h a t the
d e f e n s e m e c h a n i s m s may be i n d u c e d a n d o r may be d e p e n d e n t
on
protein
synthesis.
Stripe
rust
Ta xonomy
Puccinia
s t r i i f o r mi s
class Basidiomycetes,
The
na me
often
used
in
early
Europe.
Environment
is
classified
the club fu n g i,
P u c c i n i a . glumarum
used
in
West,
( S c h m. )
literature
No a l t e r n a t e
and i n f e c t i o n
Erikss.
is
the
order Uredin.ales.
and i s
host
in
a n d He nn.
still
was.
frequently
k nown.
process
Oversummering and o v e r w i n t e r i n g
Sharp
rust
(1963)
overwintering in
wheat
fields
Mont ana.
area.
infected
in
to the
found
native
the
The y s u g g e s t e d
importance
this
a n d Hehn
grasses
Flathead
that
no e v i d e n c e
these
adjacent
Lake
area
grasses
epidemiology of s t r i p e
Dormant m y c e lia ,
leaves,
were
of
to
infected
of
W estern
were
rust
stripe
of
minor
on w h e a t i n
w h i c h can s u r v i v e on f a l l -
important
only
if
these
leaves
(1967),
stripe
in
Sierra
survived.
According
rust
of
wheat
to
was
Tollenaar
found
to
and Houston
oversummer
the
1,8
Nevada a r e a
more i n
spp.,
of
wild
grasses
at
altitudes
of
1800 m e t e r s
b e l o n g i n g t o E l v mu s s p p . ,
stage
or
the
striiform is
an a l t e r n a t e
primary
uredomycelia
infection
H o r d e um
is
not
host,
inoculum
for
k n o wn
the
survival
the
next
on v o l u n t e e r
wheat
susceptible
grasses.
from
to
have
and
a sexual
production
s e a s o n must
or
possibly
be f r o m
by
Dissemination
uredospores
methods
have
been
to
the
seedling
and
the
mixture
adult
and t h e n
dusted
(1967),
used
uredospores
(1981)
o f ILl s t r i i f o r m i s
brush
s a me
from
adaxial
plants.
but
sprayed
on t h e
a
occurs
by
air-borne
uredomycelia.
suggested
Cartwright
mixture
paint
dissem ination
originating
infection.
cross
■ ■
N atural
a
or
and S i t a n i o n spp. (T able 3).
Since
of
California,
to
induce
applied
spores
a fine
and t a l c
surface
of
Mares
and
the
plant
inoculum.
nonquantitative
Different
a rtific ia l
covering
(1:5)
leaves
Cousen
first
Tollenaar
method
with
of
a
of
both
(1977)
used
with
water
and Houston
of
on t h e n e w l y u n f o l d e d p r i m a r y l e a v e s
rubbing
19
T ab1 ® 3.
Hosts attacked
in California.
by P u c c i n i a
1/ .
Agroovron c ris ta tu m
Bromus c a r in a tu s
Bromus m a rg in a tu s
Bromus u n io lo id e s =
Bromus c a th a rtic u m
Elvmus co n d en satu s
Elvmus g la u cu s
Hordeum brachvantherum
Hordeum deoressum
Hordeum Iubatum
striiform is
We s t ,
Hordeum leoorinum
Hordeppi YU1R^re
P h a la r is m inor
Poa p r a te n s is
S ita n io n h an sen i
S ita n io n h y s tr ix
S ita n io n jubatum
T ritic u m aestiv u m
1/ Compiled by T o lle n a a r and Houston ( 1967) .
Uredospore
germination
According
s t r i i f o rmis
are
fluctuations.
cause
lower
moderate
larger
were
to
Sharp
extremely
Th e
(m obility
highest
in
Macko e t
0 .0064
to
0.03
al.
(1977)
noted th a t
could
uredospores
periods
periods,
spore
inhibitors
can
of
ions of
c m2 v o l t " " ^ s e e " 1 )
formation,
of
several
characteristics
be r e l a t e d
concentration
of
t o t h e age and
of t h e s p o r e s , e n v i r o n m e n t a l and h o s t
i o n s and t h e r a t i o
and
during
the v a r ia tio n
stripe
during
environmental
concentration.
germination
maturity
of
concentration
During th ese
authors observed in the
rust
to
ion
germination
pollution.
size
uredospore s
sensitive
atmospheric
uredospore
air
( 1 967 ),
and
conditions
type
of
air
and l e v e l s of e ndogenous s t i m u l a t o r s
germination.
The
self-inhibitor
methyl
20
cis-3 , -dimethoxy cinnamate,
was i s o l a t e d
by
Macko e t
al.
( 1977) .
Light
Mares
rust
and
Couseri
(1977),
c o l o n i e s was f a v o r e d
stated
that
"weather
with
that
intensity
wheat
clear,
varieties
infection
types
to
were
growth
of
and
were u n f a v o r a b l e f o r r u s t
sunny
d a y s ."
influenced
jL.
that
by l o w l i g h t i n t e n s i t i e s ,
conditions
development
light
reported
Stubbs
the
s t r i i f o r mi s .
a result
of
(1967)
response
Mo r e
found
of
s ome
susceptible
a reduction
in
light
intensitie s .
Humidity
Sharp
deficits
(1965)
noted
(relative
conditions
did
that
differences
humidities)
not
for
appreciably
in
different
affect
temperature
the
process.
Previous
hydration
of
important
factor
successful
germination.
to
saturation
infection
u r e do s p o r e s
spore
for
weight
24 h r s
was
uptake.
Hydration
dark
the
or
light.
prior
to in o c u la tio n .
approximately
wa s e q u a l l y
doubled
effective
an
Germination
w a s h i g h e s t wh e n t h e s p o r e s w e r e h y d r a t e d u n d e r
conditions
was
saturated
In t h i s
due
to
c^se,
water
wh e n d o n e i n
the
21
Temperature
Tem perature
environmental
process
as
T a b l e 4.
seems
factor
indicated
in
in
to
the
be
the
most
determ inant
JLt. s t r i i f o r mi s
infection
T a b l e 4.
E f f e c t o f t e m p e r a t u r e on P u c c i n i a s t r i i f o r m i s
West, a s r e p o r t e d i n t h e l i t e r a t u r e .
Tem perature
C
Subzero
U r e d ia l s t a t e s u r v i v e d i n l e a v e s . ( E r ik s s o n and
E. H e n n in g , 1896) a s c i t e d by T o l l e n a a r and
Houston (1967) •
Minimum t e m p e r a t u r e f o r g e r m in a tio n
(M a n n e rs, 1 950) and Newt on and . J o h n s o n ,
1936). 1/
H i g h e s t g e r m i n a t i o n i n d a rk (M cC ra c k en and
B u rle ig h , 1962).
Optimum te m p e ra tu re f o r i n v i t r o g e rm in a tio n
(M anners, 1950); (Newton and Johnson, 1936),
( S t r a i b , 1940) . 1/
Optimum te m p e r a t u r e f o r y e llo w r u s t e p id e m ic s
( Zadoks, 1965).
G row th o f r u s t c o l o n i e s a r e f a v o r e d (M a res and
Cousen, 1977)•
Maximum te m p e ra tu re f o r g e rm in a tio n depending upon
th e p h y s io lo g ic ra c e ( S t r a i b , 1940).
Ten day p e rio d a t t h i s mean te m p e ra tu re i s l e t h a l
to P. s t r i i f o r m i s ( T o lle n a a r and H ouston. 1967).
U n fa v o ra b le f o r P. s t r i i f o r m i s (M ares and
Cousen, 1977)•
Te n d a y p e r i o d a t t h i s me a n ma xi mum
te m p e ra tu re i s l e t h a l to P. s t r i i f o r m i s
( T o l l e n a a r and H o u sto n , 1967).
P .s t r i i f o r m i s w as k i l l e d a f t e r 14 d a y s
( K upriyanova and Zhokhova, 1981).
Above z e r o
2 -5
10-13
12 -1 4
18 -1 9
18-22
22.3
2 2 -3 5
3 2 .4
3 4 -4 2
* '
As c ite d by Sharp (1 9 6 5 ).
E f fe c t
22
Penetration
and f u n g a l
According
to
growth.
Hendrix
(1967),
the
processes
g e r m i n a t i o n and p e n e t r a t i o n ta k e p l a c e over a s i x
hour
period.
Penetration
penetration
formation
of
does
not
of wheat
which
seem
a distinctive
com m unication).
haustorium
stem
rust,
produced
flax
rust
occur.
and
but
not
(Sharp,
several
frequently
in
no
personal
that
other
the host
noted
is
the
the haustorium
penetration,
(1981),
14
Direct
There
suggested
penetrated
Cartwright
mo r e
stomata.
rust fungus, like
and c a u s e d i n v a g i n a t i o n ,
were
to
(1979)
been s t u d i e d ,
plasmamembrane.
via
appressorium
Mares
of the yellow
have
occurs
to
of
cell
of
that
seedlings
rusts
wall
the host
haustoria
than
in
adult
plants.
The d i r e c t i o n
of
Cartwright
(1981)
the
Sim ilar
leaf.
Cousen
(1977),
adaxial
growth
predominantly
results
found
of
tube
were
that
the leaves,
was r e p o r t e d
across
reported
rust
the
to
the
C artw right
stages
unvernalized
leaf
uredospores
germinated
analyzed
of
host.
plants
on
by
of
and
the
by s e n d i n g o u t
surface
at
growth
in
veins.
(1981)
the
axis
by M a r e s
germ t u b e w h ic h grew a l o n g th e l e a f
angles
different
be
wh o
surfaces
a narrow
right
to
germ
onwards,
fungal
From
the
the
size
fifth
of
the
leaf
of
vascular
bundles
appeared
infection
tissue
to
hyphae.
between
longitudinal
between
discourage
This
the
seedlings,
the
essentially
random and
hyphae
Cartwright
and,
if
there
grow
it
did
the
hyphal
in
towards
the
on t h e
of
adult
stopped
,the
plant
(1977)
noted
after
a
the
was
fourth
tendency
of the l e a f
it
of
development
base
tip
the
developed
leaves
However,
the
to
characteristic
third
the
that
occur,
fungus
was an i n c r e a s i n g
toward
concluded
g ro w th of any s o r t
of
transverse
patterns
and
no n p o l a r .
leaves
to
that
second
of
the
infection
direction
and s u b s e q u e n t
for
so
"striped"
In
growth
restricted
bundles,
veins.
the
leaf.
hyphal
was r a r e
very
short
distance.
Mares
of
and
infection
Under f i e l d
severely
Cousen
on
leaf
age
conditions,
reduced
secondary,
bundles
transverse
and
started
unpenetrated
leaf
allowing optimal
75
micrometers
of
five
to
ten
the
on o l d e r
After penetration,
at
the
rate
a
critical
time
of
dependence
inoculation.
of d i s e a s e
s p r e a d was
leaves.
a cc o rd in g to C a r tw rig h t
runner
new
areas.
hyphae
crossed
infections
In
in
susceptible
(1981),
vascular
previously
host
plants,
d e v e l o p m e n t , germ t u b e g r o w t h as f a s t as
per
hour
and
intercellular
m icrom eters
per
hour
hyphae
were
growth
observed
24
( Mengen,
growth
19 8 1 ) .
of
a "bed” of
1981).
the
uredospores
hyphae
of,
Growth
mesophyll
septation
to
this
of
of
septation
mainly
advanced
of
on
related
(Cartwright,
mostly
on t h e
withered
stages
pustules
the
continued
and dry
to,
adaxial
and
in
of
of the
the
number
that
s e v e n on t h e
However,
stomata
stomata
of
adaxial
Salisbury
occur
were
of
the
then
percent
the
lower
production
were
completely
closely
for
in
Ross
dependent
penetration,
adaxial
pustules
surface
that
of
surface
the
will
develop
by B r i g g l e
a ratio
and a b a x i a l
and
the
Spore
is
t h a t s u r f a c e . H a y w a r d ( I 94 8) a s c i t e d
reported
a
1981).
t h e number of s t o m a t a p r e s e n t on t h e
affect
Even
60
leaf
infection
suitable
surface
infection.
(Cartwright,
of
s u rfa c e o c cu rred only
surface.
such a reas
and
1981).
occurred
on a v e r a g e ,
leaf
s t r i l f ormis
presence
of
was,
adaxial
until
Since
greatly
produced
b e n e a t h t h e a d a x i a l e p i d e r m i s and p u s t u l e s
very
on t h e
dense
c e l l . The o r i g i n
directly
S p o r u l a t i o n on t h e a b a x i a l
than
were
the
The f o r m a t i o n o f a p u s t u l e
of a mother
be
me s o p h y l l ,
particularly
haustoria
s t r i l f o r mis
found, therefore,
density
the
became
Numerous
seemed
consequence
in
areas
u r e d i a was f o r m e d .
with
leaf.
some
infection
(Cartwright,
starts
In
on
( 1 967)»
about
ten
to
respectively.
(1978), s u g g e s t e d
that
25
"...grasses
on
both
usually
sides"
of
the
Physiology of the
Mares
have about equal
diseased
components
for
and
plant
summarized
stripe
rust
infected
as
host
follows,
cells
growth,
a phase of a c c u m u l a t i o n and s t o r a g e
the
This
material,
haustorial
m etabolites
from
levels,
stage
It
leaf
has
tissue
from
the
haustoria,
cell
particular
morphological
structures
be
of
modified
by
and
light
host
fungal
of f u n g a l and
of n u t r i e n t
the
by
the
fungus."
the
gradual
export
by a c h a n g e i n p l a n t
of
hormone
in ten sities,
cells
penetrated
and
i n an
infection.
been shown t h a t
senescence
presence
there
injury.
Cousen ( 1 9 7 7 ) ,
"...fungal
a phase of a c t i v e
cells,
d i f f u s i n g from
of
host
the
the
may
leaf
tem perature
m etabolites
early
host
of
and a p e r i o d o f e x p o r t
activity
of
to
with
developing reproductive
senescence
host
series
a
which
correlated
a
in
changes
to
showed
host-pathogen
of
reserve
leaf
the
section
host
the
stomata
leaves.
(1979)
relationship
numbers of
of
was
(Mares,
a collar
little
infection
1979)*
around
host
and u s u a l l y
accelerates
However,
the
neck
morphological
The s a m e a u t h o r ,
reported
mesophyll
rust
cell
to
in
of
apart
s ome
evidence
of
combination with
collapse
to
be
one o r a s m a l l
confined
number of
26
isolated
cells
m aterial
at
cells
another
is
presence
in the
the
colony.
point
where
common
of h a u sto ria.
D ep o sitio n of a c o l l a r
the
fungus e n te r s
response
Little
is
of
the
k n o wn o f
the host
hpst
the
of
to
the
composition
of t h e c o l l a r and i t s r e l a t i o n s h i p t o t h e h o s t c e l l w a l l s
( Ch o n g a n d
The
Harder,
rust
accumulation
fungus
of
pustule
of
derives
normal
many
and
to
as
that
that
sections
indicated
accumulated
host
cells
starch
adjacent
to
fungal
To s t u d y t h e n u t r i e n t
experimental
approach
mycelium
grows
(Medgen,
1981).
only
is
in
of
for
starch
in
direction
of
in
to
nine
leaves.
infected
the
leaves
chloroplasts
of
hyphae.
uptake of the r u s t f u n g i,
must
by
content
healthy
of th ese
The
reported
increased
of
the
19 8 1 ) .
the
also
the
wheat le a v e s
tw ice
focus
(Hedgen ,
It
M icro g rap h s of c ro s s
that
a
alteration
(1970),
infected
days,
by
transport.
Strobel
P. s t r i i f o r m i s
acts
m etabolites
nutrients
phloem
Ma c D o n a l d
tw elve
I 982).
consider
restricted
Th e n u t r i t i o n a l
that
the
the
fungal
areas
w ith in the le a f
(
r e q u i r e m e n t s of a r u s t
f u n g i c a n be s t u d i e d s t a r t i n g w i t h t h e r u s t m y c e l i u m i n
axenic
of
a
cultures.
rust
fungus
This method has
(e .g .,
a
a c i d s , a s u l f u r amino a c id ,
defined
the
basic
of
needs
balanced
mixture
amino
different
sugars, inorganic
27
nutrients
Burrell
and
and
some
minor
Lewis
(1977),
considered
serine
successful
establishm ent
fungus
in
It
the
resistant
leaves
reaction
was
has
by
be
as
steroids).
Medgen
(1981),
important,
maintenance
of
in
the
of
the
by
wheat
the
rust
of
that a
susceptible
Rego.
inoculated
and
This
plants
profiles.
Cousen (1977),
been
of
variety,
incubation
suggested
interactions
interaction
not
and Sharp (1965),
content
product which d i f f u s e s
III.
may
from
into
the
adjacent
that
host
cell
caused
by a
of
the
host
tissue.
This
be
site
host
proven.
I n t e r a c t i o n o f m icroorgan ism s i n wheat
Yar wood
(1959)
ma y
unrelated
microorganism.
literature
(Table
be
reported
pathogen
the
to
and
protein
incompatible
cell-fungus
idea
alanine
temperature
Mares and
in
in
induced
different
toxic
cited
w a s r e p o r t e d by S t r o b e l
existed
d a ma g e
and
as
such
host.
difference
at
nutrients
that
predisposed
regarding
5) .
to
plants
attack
There are
pathogen
attacked
by
several
a
by o n e
second,
reports
interactions
in
in
£*.
28
Table 5
M icroorganism i n t e r a c t i o n s o c c u r r in g in
aestivum rep o rted in the l i t e r a t u r e .
P resence
of
m icroorganism
A ffe c ted th e
in c id e n c e o f
Gg
2/
>
Mg
Rs + Gg
Mg
Eg •
BYDV
>
<
>
>
Mg
Pr
Mg
Mg
Ln
—
Mg
Ph
>
Ln
>
Ln
Ln
Ln
Ln
I/
Pr
Pr
Ps
Xt
-
Pc
<
Ln
WSMV
>
Hs
F .spp
<
Hs
Author
Bensaude ( 19 2 6 ).
Sprague ( 1950) .
Sprague (1 9 5 0 ).
C h este r (1944)
B ro k p n sh ire ( 1974) .
Sanderson ( 1964) .
(C ite d by Brokens h i r e 1974.)
J e n k in s and Jo n es
( 1980) .
Jo n es and J e n k in s
(1978) .
Van tier Wal ( 1974) .
Hyde (1 9 7 8 ).
Hyde (1 9 7 8 ).
Jo n es and Roane
( 1979) .
Jo n es and Roane
(1979) •
Adlakha and Raych audhuri (1 9 7 5 ).
T in lin e ( 1967) .
^Og=Gaeumannomvces sraminis v a r . t r i t i c i
Mg= Mvcosohaerella graminicola
Rs= Rhizoctonia so la n !
Es=E r v s ip h e g r a m i n i s
Ln= Leotosphaeria nodorum
Ph= Pseudocercosporella herpotrichoid es
Ps= Puccinia s t r i i f o r m i s
Xt= Xanthomonas translucens
Pc= Pseudomonas cepacia
WSMV= Wheat Streak Mosaic Virus
F.spp= Fusarium s p e c i e s .
2/
>, <, - , i n d i c a t e s t h a t p r e s e n c e o f th e f i r s t
patho gen i n c r e a s e d , d e c r e a s e d or d id no t a f f e c t t h e
inciden ce of a second pathogen, r e s p e c t i v e l y .
29
Plants
graminis
infected
(1950)
However,
confirmed in
Hyde
very
of
and
be
of
infected
infected
the
characters
factors
several
in
host
al.
been
and
was
less
effects
of the
two p a t h o g e n s
interaction
spp. r e p o r t e d
is
than
Cheyenne, which
is
a
of
the outcome,
must
results."
that
predicted
occurring
is
the
tim ing
in
proportion
also
As a
leaves
of
leaf
by a d d i n g
separately.
M. g r a mi n i c o l a
by C h e s t e r
that
a g e a n d ma ny o t h e r
noted
was
between
Puccinia
one h o s t
and
the
the
the
between
assessment
he
on
evident
affect
interpreting
pathogens
mo r e
sites
experiments,
both
cultivar
et
not
and
occurring
probably
killed
on t h e
(1929)
studies
attacking
of i n f e c t i o n ,
or
Puccinia
have
o r G.
be mo r e
Shipton
nodorum
The
experimentation
with
his
becomes
pathogens
phenomenon.
of
The o n l y
rust
"...it
interactions
level
important
summary
that
of
and p a t h o g e n
methods
by
observations
concluding
different
complex
to
by B e n s a u d e
(cited
Leotosphaeria
noted
inoculations,
host
in
between
possibility
effects
reported
infection
field
g r a mi n i s
laboratory.
(1981),
striiform isf
were
respectively
these
the
interaction
the
solani
t o S-=, t r i t i c i
Sprague
1971)*
G a e u m a n n o my c e s
and R h i z o c t o n i a
susceptible
and
by
and a
( I 9 4 4) i n O k l a h o m a
susceptible
to le a f
( c a u s e d b y P. r e c o n d i t a ) . Th e l o w i n c i d e n c e
of l e a f
30
rust
that
year
trltici
which
benefit
of
by i t s
between
to
an e a r l y
tissues
diminishing
first.
leaf
between
They
pathogens
found
Septoria
as
studied
no
attack
by
was
by d i s e a s e
S.
the
greatly
tissues.
species
( M.
Jenkins
and
significant
determined
of
However,
rust
d e s t r u c t i o n of wheat l e a f
a n d L l n o d o r u m ) wa s
(1980).
grain
in
leaf
interaction
graminioola
Jones
destroyed
Septoria
outweighed
The
was a t t r i b u t e d
interaction
scores
or
by
yield.
Sanderson
pseudothecial
and
Hampt on
states,
(I 9 80)
occurred
crop,
noted
typically
glume
reported
Mvcosphaerella
c ommonl y o c c u r r e d on t h e
Jones
(1978),
s a me l e a f .
that
at
blotch
while
the
the
L e p t o s p h a e r i a 1,
speckled
leaf
blotch
growth stag e s
the
flag
leaf
pseudothe cia
earlier
of
than those
A trip le
Pelletier
et
of
Leptosphaerla
Mv c o s o h a e r e l l a
interaction
al.
(1974),
was
where
the
of the
and
R e s u l t s , o f w o r k by S a n d e r s o n a n d H a m p t o n ( 1 9 7 8 ) ,
that
t wo
HoweVer, J e n k i n s and
earlier
infected
and
that
nsAfiXUin
ear.
showed
matured
graminioola.
reported
in
oats
by
pathogens
s t u d i e d were
B a r l e y Y e l l o w D w a r f V i r u s (BYDV) , P u c c i n i a c o r o n e t a a n d
Seotoria
plants
avenae
f.
inoculated
severity
levels
sp.
avenae.
with
BYDV
,by
Results
were
JLl. SY-S-S-S.S.. f .
indicated
infected
sp.
at
S-Y-SSSS
that
higher
but
31
coronata
due
to
was
the
parasites,
can use
diminished.
fact
while
that
nutrients
plant
from
is
of
e a c h on t h e
the
simultaneous
such
separate
action
of
effect
as
obligate
parasite
and
senesced leaves.
pathogens
the
that
a facultative
as
s t r i i f o r mi s T o n e m u s t e v a l u a t e
effects
explained
c o r o n a t a a n d BYDV a r e
JL. a v e n a e
When c o n s i d e r i n g
more
T hey
action
H jl g r a mi n i c o l a
other.
two
and
or
P♦
not only the i n d i v i d u a l
o r g a n i s m s , but a l s o
the
of
the
effect
of
32
MATERIALS AND METHODS
General
Wheat
resistance
cultivars
and
'A nza',
were
Cultivars
Cl
(Israeli),
were
a
to
selected
'Wampum',
suitable
range
of
b o t h JJj . s t r i i f o r m i s
and
for
' L e m h i 1, Cl
1 52 8 4 ;
Plants
having
susceptibility
fiz a m in iilfils .
studies.
procedures
these
11415;
Cl
interaction
' B a a r t 1f CI 1 6 9 7 ;
17 6 9 1 ;
and
'Lakhish'
used.
were
grown i n
a glasshouse
maintained at
2 C i n a one t o one m i x t u r e of s an d and s t e r i l e
soil
in
aluminum
was p r o v i d e d
12 h r
pans
each
cultivar
area
for
and
inoculated
Each
along
the
each c u l t i v a r .
( T o ttm a n ,I 979).
total
when
After
per c u l t i v a r
non
Supplemental
green
p a n wa s
border
Plants
they
planted
of
the
were
light
present
not
inoculated
an
a
of
equal
w e r e g r o w n f o r 6 - T2 d a y s
growth
symptoms
on
the
were
stage
appeared,
pe r pan w e re e v a l u a t e d
area
15 s e e d s
pan u s i n g
reached
disease
with
12
nine
by a s s e s s i n g
oldest
p r e s e n c e of p y c n i d i a a l s o was r e c o r d e d .
which
c la y loam
by 4 0 0 w a t t m e t a l h a l i d e l a m p s t o a s s u r e
photoperiod.
plants
20 x 20 x 5 cm.
17+
leaf.
The
Control plants
m aintained
in
all
experiments.
A culture
of
H 1. g r a m i n i c o l a
( ORG- 8 2 0 7 6 - 1 ) ,
obtained
33
f r o m H y s l o p Fa r m , Or ego n A g r i c u l t u r a l E x p e r i m e n t S t a t i o n ,
was
used
exclusively.
striifo rm is
The
Bozeman
isolate
u s e d i n a l l e x p e r i m e n t s wa s c o l l e c t e d
■ ,
from a f i e l d
of
the wheat c u l t i v a r ,
m a i n t a i n e d a t 5 C i n vacuum s e a l e d
Agricultural
Experiment
'
Itana.
of
in
'
.
P.
1979
‘
r .*
,
Spores were
tubes at
the
Montana
Station.
i
M. g r a mi n i c o l a
adjusted
to
suspension.
extract
five
increased
concentration
The l i q u i d
on a
a n d 900
shaker
laboratory
according
pump
to
method
P. s t r i i f o rmis
inoculation
humid chamber a t
media
per
abundant
to
a
developed
were
spores
were
room t e m p e r a t u r e
of
After
Shaker)
at
sporulation
of
et
using a
atom izer
al.
opened two h o u r s
placed
ml
water.
DeVilbiss
by E y a l
and
96 y e a s t
P l a n t s were i n o c u l a t e d
tubes
and th e
spores
W rist-Action
temperature,
connected
the
I 0?
liquid
ml d i s t i l l e d
(Burrel
t h e f u n g u s was o b t a i n e d .
diaphragm
of
in
me d i u m wa s p r e p a r e d u s i n g
+ 9g sucrose
days
ambient
a
was
(1983).
before
on a s l i d e
to allow
in
a
hydration.
I n o c u l a t i o n wa s p e r f o r m e d by d i s c h a r g i n g a COg g u n l o a d e d
with
40 mg o f
hydrated uredospores twice
in a s e tt lin g
t o w e r to i n d u c e a slo w and u n i f o r m
precipitation
of the
spores
mobile
below.
on t h e
plants
After the f i r s t
degrees
from
located
on t h e
surface
s h o t , t h i s m o b i l e s u r f a c e w a s m o v e d 180
its
original
position
to
ensure
a
more
34
uniform
dissem ination
incidence
was
assessed
and s i g n s
of the
R e a c tio n s were
pustules;
were
of
the
uredospores.
Disease
estimation
symptoms
by v i s u a l
disease
using the m odified
coded as r e s i s t a n t
moderately
surrounded
resistant
by
of
Co b b s c a l e .
(R) i n t h e a b s e n c e o f
(MR) wh e n s m a l l
necrotic
tissue;
pustules
m oderately
.
susceptible
chlorotic
( MS )
when
tissue;
reaction
in
developed
the
plant
was
types
Th e
multiplied
the
of
by
( S ) w h e n no d e f e n s e
detected
as
number
by t h e
infection
and
when
assigned
the
to obtain
experiment
different
in
pustules
inoculated
of
and
at
A suspension
the
MR=O.4 a n d
infection
type
was
covered as e s t i m a t e d
coefficient.
A
was
designed
wheat
susceptibility
g r a mi n i c o l a.
the
o f each
the
using
Procedures
five,spring
levels
s t r i i f o r mi s
to
percentage of l e a f
I n t e r a c t i o n ■e x p e r i m e n t
progression
calculated
S = I , MS=O. 8 ,
Cobb s c a l e
This
wa s
m ultipliers
Specific
inoculum
surrounded
freely.
infection
using
were
and s u s c e p t i b l e
A coefficient
R=0.2.
pustules
s ame
time
to
study
cultivars
to the
The w h e a t
with
measured
disease
having
pathogens
plants
P.
were
amounts
of
pathogen.
of
budding c o n i d i a
o f Mj. g r a mi n i c o l a
was a d j u s t e d to a c o n c e n t r a t i o n
inoculum.
Ten
experimental
Plants
were
for
of
unit
containing
the
the
plants
three
with
graminicola
alone,
alone
placed
wa s
disease
10
C dew
stage
on
each
cultivars.
12
in
the
with
settling
treatments,
both
tower
both
d)
pathogens
chamber
cultivars
were:
a)
together,
P.
c)
M.
control.
to
( d a r k ) a n d 10 C ( l i g h t ) .
randomized
five
treatm ents
Three days a f t e r i n o c u l a t i o n ,
the
wheat
a completely
Disease
b)
and
sprayed
g r a mi n i c o l a wa s , a p p l i e d
design
four
p e r ml o f
inoculation.
replications.
s t r i i f o rmis
growth
were
t h e Z 1. s t r i i f o r m i s
experiment
at
was
five
same t i m e .
The e x p e r i m e n t a l
and
inoculum
inoculated
pathogens at
f i r s t ; then
ml
o f I O^ s p o r e s
p l a n t s w e r e mo v e d f r o m
a growth
chamber
set
at
4.5
C
Twenty days a f t e r i n o c u l a t i o n ,
plants
w e r e m o v e d a g a i n t o a g r o w t h c h a m b e r s e t a t 16 C
(dark)
a n d 21 C ( l i g h t ) .
At
the
squares
time
of
rust
3 x 3 cm w e r e
inoculation,
placed
at
the
polyethylene
same
level
as
the
p l a n t s a t the base of the s e t t l i n g tow er to d e te r m in e the
number
of
spores
germ ination
remained
in
removed
and
disseminated
percentages.
the
cut
de w
The
chamber
into
five
per
unit
area
polyethylene
for
24
strips
hours.
for
and
spore
squares
T lie y
were
m icroscopic
36
examination.
on
each
Twenty
strip.
related
to
The
the
This
microscopic
number
area
number o f v i a b l e
Interaction
one
of
the
spores
pathogen.
I)
no
and
to
Anza,
infected
by
a
com binations
Lemhi,
and
design with
inoculation,
were
three re p lic a te s
coded
00
00;
2)
I,
c o d e d SO 0 0 ;
s t r i i f o r mi s
inoculated
at
time
I ,
c o d e d 00
g r a mi n i c o l a
inoculated
at
time
I
inoculated
at
time
I,
time
c o d e d OS OR.
reached
later.
(light)
SO OR;
and
2
Z*,
5)
stage
12,
and
C
were
(dark)
made
with
21 ,
26
chamber
and
12
hr
31
JtLi.
inoculated
at
at
at
time
time
2,
seedlings
second was
a
JL.
IL*. g r a mi n i c o l a
w a s ma de a s
the
3)
s t r i i f o r mi s
7) b o t h p a t h o g e n s i n o c u l a t e d
inoculation
as
M_«_
HO; 4)
both pathogens in o c u la te d
I n c u b a t i o n was i n a g r o w t h
Assessments
I
6)
The f i r s t
growth
and
2 a n d JBj . s t r i i f o r mi s
I , c o d e d OS R0;
c o d e d SO HO;
coded
four
Baart )
time
2,
was
and
at
time
the
primary
inoculated
at
the
study
g r a mi n i c o l a
inoculated
was
o f l e a f was d e t e r m i n e d .
already
organized in a s p l i t - p l o t
follow s:
field
designed
treatm ent
(Lakhish ,
spores
of a seco n d p a t h o g e n when i t
tissues
Seven
cultivars
was
patterns
on
microscopic
counted
£.
experim ent
inoculated
were
germinated
per area
experiment
colonization
of
fields
set
17 d a y s
a t I 8. 5 C
photoperiod.
days
after
the
37
initial
inoculation.
After
which
the
had
been
last
used
by c l i p p i n g a l l
then
placed
weighed to
assessm ent,
of
to
assess
an
oven
at
at
score
Germination
pathogens
was
germination
of
spores
observed
on
described,
uredospores
o f .Ejl s t r i i f o r m i s
striiform is
in
uredospores
o f Ej, s t r i i f o r m i s
the
which
experiment
wa s
design with
Field
nine
leaves
were
the a u ric le .
C for
72
removed
Th e y w e r e
hr
and
then
with
presence
the
of
both
inoculum
polyethylene
treatm ent
as
sheets
as
follows:
I)
a l o n e ; 2) u r e d o s p o r e s
o f M1. R r a m i n i c o l a
in
the
presence
M». SILiLm i l l w a s
performed
three
the
using
treatments
a
P.
conidia;
3)
of
sterile
grown.
completely
and t h r e e
of
This
randomized
replications.
<
observations
Using
occurred
collect
wheats
natural
in
infection
Bozeman
during
of
E^_ s t r i i f o r mi s f w h i c h
1 983 »
it
was
possible
to
i n f o r m a t i o n i n two g r o u p s o f s p r i n g and w i n t e r
i n o c u l a t e d w i t h Ml g r a m i n i c o l a . Rows t h r e e
meters
l o n g w e r e p l a n t e d on S e p t e m b e r 2 0 , I 982 ( w i n t e r w h e a t s )
and on A p r i l 25 , 1983 ( s p r i n g w h e a t s ) . Each r o w ,
one
1
level
in
the
previously
in
symptoms
at
50
same
d e t e r m i n e dry m a t t e r .
Interaction
media
the
them e q u a l l y
in
the
per
genotype,
wa s
divided
in
the
middle;
half
planted
for
J
■
Ml
i
38
i^ r a g i j n i c o X a i n o c u l a t i o n
inoculate,
a
back-pack
and h a l f
sprayer
kept
was
as a c o n tro l.
used
To
containing
a
c o n c e n t r a t i o n o f 1 0 ? s p o r e s p e r ml o f s u s p e n s i o n .
Five
inoculations
four
were
ma de
on t h e
winter
genotypes
on t h e s p r i n g g e n o t y p e s on a w e e k l y b a s i s .
and
Inoculations
w e r e p e r f o r m e d i n t h e e v e n i n g . To i n c r e a s e t h e d e w o n t h e
leaf
to
surface,
ten
the
hours
inoculation
on
using
were e v a lu a te d
A u g u s t 10,
stages
three
a
65
rows
plastic
o n J u l y 27»
nights
for
eight
after
each
Winter
genotypes
1 983 a n d s p r i n g g e n o t y p e s on
p l a n t s were
ILl s t r i i f o r mi s
and
covered
tarpaulin.
(m id-anthesis)
Co b b s c a l e
were
consecutive
1983. Most o f t h e
development).
modified
inoculated
and
was
75
between growth
(medium
assessed
g r a mi n i c o l a
v is u a l e s t i m a t i o n of the n e c r o t i c l e a f
using
m ilk
the
by r e c o r d i n g
a r e a on t h e
a
flag
le a v e s of each genotype. R e s u lts o b ta in e d were analyzed
using
regression
analysis.
RESULTS
I n t e r a c t i o n E x p e r i ment
Results
of
previous
indicate
the
shortening
the
experiment
a latent
was o b t a i n e d
4.5 t o
10
im portance
latent
period
to
a
Successful
warm
p u s tu le s , of
Stripe
rust
tritic i
pustules
blotch
In
Since
the
7.3
amount
obtained
regime
with
of p y c n i d i a
colonizing
necrotic
uredospore
the
viable
of
leaf
of
the
areas
both
caused
uredospore
same
of
leaf.
septoria
germination
germination
uredospores
area
affected
each c u l t i v a r
presented
when t h e d i f f e r e n t
color.
disease x c u ltiv a r
n e ce ssa ry to analyze
are
Mj . g r a m i n i c o l a
distinguishable,from
to
this
o f 14 t o 21 C.
presence
to a black-brownish
had a s i g n i f i c a n t
6 results
for
In
on
had a t e n d e n c y to change from th e norm al
experiment
approximately
tem peratures
from a cold
was
the
c lo s e
s t r i i f o r mi s
this
23 d a y s
plants
j-L. s t r i i f o r m i s
yellow-orange
P.
of
regime
with
by Mj . g r a m i n i c o l a w a s
warm,
unpublished)
o f Mj . g r a mi n i c o l a .
inoculation
Necrosis
( Madariaga,
of
period
by m o v i n g t h e
C
pathogens.
studies
A
of l e a f
cuI t i v a r s
was
was
per
variable.
37- 3
% with
mm^ o f
leaf.
by £*. s t r i i f o r mi s
interaction it
separately.
area affected
was
In Table
by t h e
rust
were i n o c u la te d only w ith
40
Table 6.
P e r c e n t a g e l e a f a r e a a f f e c t e d and c o e f f i c i e n t s
of i n f e c t i o n of f i v e wheat c u l t i v a r s i n f e c t e d
by £ t i . c £ i n i a f i t r i i f o r m i f i i n t h e p r e s e n c e o r
a b s e n c e o f Mv c o s p h a e r e l l a g r a m i n i c o l a .
Days a f t e r in o c u la tio n
23
C u ltiv a r
25
P e r c e n t C o e ff.1 /
l e a f a re a
in f.
-32
P e rc e n t C o e ff.
l e a f a re a i n f .
P e rc e n t
l e a f a re a
C o eff.
in f.
L akhish
L ak. Mg. 2 /
11 A3/
4 A
9 A
3 A
6 A
5 A
5 A
4 A
29 A
26 A
23 A
21 A
Anza
Anz. Mg.
15 A
9 A
4 A
2 A
12 A
10 A
2 A
3 A
32 A
I B
6 A
0 A
Lemhi
Lem. Mg.
40 A
18 B
40 A
18 B
54 A
33 B
54 A
33 B
71 A
68 A
71 A
68 A
B aa rt
Baa. Mg.
27 A
13 A
27 A
13 B
52 A
19 B
52 A
19 B
81 A
56 A
81 A
56 B
Wampum
Warn. Mg.
16 A
3 A
7 A
I A
31 A
3 B
13 A
I B
57 A
19 B
23 A
8 A
C.V
62
37
33
36
28
54 A
34 B
40 A
31 B
%
62
_ , . •;
,
'■
Comparison u s in g o rth o g o n a l c o n tr a s t:
A ll c u l t i v a r s 22 A
A ll c u l . Mg.
9 B
17 A
7 B
31 A
14 B'
25 A
12 B
I / I n d i c a t e s a d ju s te d v a lu e s u sin g th e c o e f f i c i e n t o f in f e c tio n .
L a k h is h MS= 0 .8 . Anza R= 0. 2, Lem hi and B a a r t S= 1.0 and Wampum
MR= 0 .4 .
2 / Mg= i n d i c a t e s Z^. s t r i i f o r m i s i n f e c t i o n i n p r e s e n c e o f M.
g ra m in ic o la
3 / P a ir s o f v a lu e s v e r t i c a l l y fo llo w e d by th e same l e t t e r a re
n o t s i g n i f i c a n t l y d i f f e r e n t a s d e te r m in e d by LSD(P< 0.05) o r Tt e s t (P< 0 .0 5 ) in case o f o rth o g o n a l com parison.
•
3
-1
41
S-i.
striifarm is
(treatment
^raffiinicala
adjusted
a) a n d w i t h
(treatm ent
values
using
b).
striiform is
Also
the i n f e c t i o n
included
+ M.
are
type observed
the
i n each
cultivar.
There
was
a
progressive
affected
by r u s t
studied.
Thirty-two
cultivars
L e mh i
infection
as
inoculation
days
and
after
Baart
by t h e
significant
area
affected
cultivars
wh e n
cultivar
Lakhish,
interaction
showed
susceptible
coefficients
than
the
of
moderately
D u n c a n ' s New M u l t i p l e
interaction
differences
in
Anza,
1%
it
Anza
Ra n g e T e s t
between
s t r i i f o r mi s
in the low est
s t r i i f o rmis
in
amount
some
was
when
3 2 days
leaf
possible
it
was
after
area
a resistant
st r i i form is.
colonized
not
to
of
the
With t h e
detect
infected
of
by
an
P.
o r i n t h e p r e s e n c e o f IL. g r a m i n i c o l a .
percent
produced
of
by
difference
cultivar
leaves
higher
area
cultivars
IL. g r a m i n i c o l a w a s a l s o p r e s e n t .
s t r i i f o rmis alone
isolate
five
inoculation,
a n d H t. g r a m i n i c o l a w a s e v i d e n t
cultivar
the
leaf
).
The
The
of
L a k h i s h a n d Wampum ( 2 3 ) a n d r e s i s t a n t
determined
(P < 0 . 0 5
leaf
on
( 7 1 a n d 81 r e s p e c t i v e l y )
susceptible
( 6)
after
increase
by
both
It
inoculation,
affected.
reaction
is
However,
to, t h e
possible
pathogens
showed
were
this
Bozeman
that
when
assessed,
42
necrotic
being
tissue
caused
pustules
whether
L±.
and
the
c a u s e d by i L ^ s t r i i £ o r f f i i s w a s c o u n t e d a s
by
pycnidia
necrotic
siriifarm ia
showed
I f i i ca l a .
of
assessment
and
or
a decrease
presence
it
in
leaf
area
but
significant
difference
coefficients
of i n f e c t i o n .
the
Wampum
cultivar
the
tended
to
was a l s o
lower
s t r iifo rm is
amounts
of
and l o w e r
striiform is
given.
of
of
was
a
dates
in
striiform is
on
pattern
the
to
w h e n M.
cultivars
o f Ml g r a m i n i c o l a
to
be
of
cultivars
the
disease
t he r e
Whe n a l l
coefficients
in
by t h e l a s t
assessment
area
to
affected
infection
were i n f e c t e d
by P.
by
P.
by P.
alone.
Table
The
two
B aart1
presence
leaf
s t r i i f o r m i s t h a n wh e n t h e s e
cultivar
by r u s t
s how a s i m i l a r
present.
due
c u l t i v a r , Lemhi
disappeared
all
of
conclude
were
first
The l e v e l
were a n a ly z e d t o g e t h e r , the
In
The
the
cultivar
on
to
c u l t i v a r s w ith a lo w e r amount of r u s t
g r a mi n i c o l a
caused
in
absence
symptoms
affected
differences
With
the
possible
s ra B in ififila .
gram in i co la
dates,
not
chlorotic
evaluation.
the o th er
was
In
for
7,
the
each
JLl s f r I i f f i r j a f s
presence
d i s e a s e , wa s
inoculation.
In
of
percentages
plants
possibly
some
in
of
plants
infection
category
due
to
the
cases
a
few
for
type
O1 t h e
method
plants
of
in
each
are
absence
uredospore
the
pans
Table 7.
Percentage
of
plants
in
each
ZtissA n i a
s t r i i f o r mis i n f e c t i o n t y p e i n o c u l a t e d a l o n e or
i n c o m b i n a t i o n w i t h Mvcosoha e r e l l a g r a m i n i co l a .
I n f e c t i o n Type
Cultivar
Lakhish
L a k . Mg.
Anz a
Anz.
0 1/
2/
33
#
Mg.
22
26
Le mhi
L e m.
Mg.
7
19
Baart
Baa.
Mg.
Wampum
Warn.
Mg.
R
MR
MS + S
O
O
41
52
26
4
78
74
O
■0
0
0
O
O
0
0
93
81
O
II
• O
O
4
56
96
33
7
74
O
7
82
19
II
0
1 / Z-=L s i r i i f o r a i s i n f e c t i o n t y p e c a t e g o r i e s . 0= a b s e n c e
o f d i s e a s e ; R= r e s i s t a n t ; MR= m o d e r a t e r e s i s t a n t ; MS=
m o d e r a t e s u s c e p t i b l e a n d S= s u s c e p t i b l e .
2 / R e s p o n s e t o £_«. s t r i i f o r m i s i n t h e p r e s e n c e o f
M.
graminicola.
apparently
presence
did
of
Ht
percentages
studied.
of
occurred
plants
or other
in
the
s t r i i f o rmis
moderately
0 in
result
type
by
was
days
more
after
of
8,
by H«. g r a m i n i c o l a
in c r e a s e , with
plants
M.
each
g ra min i cola
in
the
the
either
s t r i i f o r mi s
first
the
case
of
of P.
susceptible
were
P.
was
before
Except i n
percentages
are
given.
Baart
These
all
and
of l e a f
the
Range
not
Test
cases.
Wampun
( P < 0.05).
significantly
area
percentages
reduced
or
by
Sh o we d
Leaf
affected
tended
Thirty-two
to
days
significantly
by M. g r a mi n i c o l a
t h a n d i d L a k h i s h a n d Anza a s d e t e r m i n e d
cultivars.
in
inoculation
the
tim e , in
inoculation
was
of
In g e n e r a l , changes
g r e a t e r amounts of l e a f a r e a a f f e c t e d
Lemhi,
of
o f Ht g r a m i n i c o l a .
In Table
M ultiple
cultivars
to t h e Bozeman i s o l a t e
to
the
inhibition
apparent
plants
the
in
conidia
SLt
necrosis.
cultivar
susceptible
when
all
of
caused
of
However,
increases
unknown r e a s o n s .
, percentages
presence
after
category
the
caused abundant
striiform is
caused
percentages
23
Anza, a r e s i s t a n t
the
be
tendency
assessment
pathogens
in
infection
This
inoculum.
&raminicola
germ ination
g r a mi n i c o l a
rust
receive
This.m ay
uredospore
present.
not
by D u n c a n ' s New
area
different
affected
from
the
in
other
45
Table 8.
P e r c e n t a g e
l e a f
area
a f f e c t e d
M! . £ o s ^ j i a s z e l l s S r a m i i i iI fifiiI a i n t h e p r e s e n c e
absence of P ucc in la s t r i i f o r m i s .
Cultivar
Days a f t e r
23
inoculation
25
by
or
32
Lak. Ps. I/
Lakhish
2/
0 A
0 A
2 A
I A
19 A
12 A
Anz. P s .
Anza
0 A
I A
4. A
4 A
27 A
24 A
Lem. P s .
Le mhi
4 A
2 A
II A
5 A
25 A
46 A
Ba a . Ps.
Baart
4 A
, 0 B
I8 A
7 B
39 B
67 A
Warn. Ps .
Wampum
3 A
3 A
I5 A
I2 A
34 B
71 A
52
37
C. V.
129
%
Comparison u s i n g o r t h o g o n a l
All
All
I/
2/
c u l . Ps .
cultivars
2
I
contrast:
A
A
A
B
10
6
29 B
44 A
I n d i c a t e s p r e s e n c e of
Kraminicola.
P a i r s o f v a l u e s v e r t i c a l l y f o l l o w e d by t h e s a m e l e t t e r
a r e n o t s i g n i f i c a n t l y d i f f e r e n t a s , d e t e r m i n e d by LSD
( P < 0.05) or T - t e s t , ( P < 0.05) in case of o r t h o g o n a l
comparison.
Significant
interactions
b e t w e e n M1. g r a m i n i c o l a
P. s t r i i f o r mis w e re o b s e r v e d f o r B a a r t , and i n
disease
a s s e s s m e n t , f o r Wampum.
assessments
an
of
increase
presence
of
Baart
in
Mt
the
this
At t h e f i r s t
interaction
amount
of
a l z i i f a rm ia -
wa s
the
the l a s t
two d is e a s e
positive
g r am ini co l a
At
and
last
in
with
the
disease
46
assessment
that
the
the
first
favored
R j,
profile
(16
to
21
regime
It
incubation
the
C) i n d u c e d
or
of
absence
showed a tendency
is
greater
possible
(4.5
to
10 C)
to
the
warm
shifting
wa s
observed
Kj. g r a m i n i c o l a
of s t r i p e
rust.
to have l o w e r
activity
in
( P < 0.05).
Th e
the
in
the
ability
(Table
9) ,
in
numbers of
plants
the
with
c u l t i v a r s Le mh i
by D u n c a n ' s New M u l t i p l e
cultivar
Range
Anza s h o we d a c o n s i s t e n t
absence of p l a n t s w ith p y c n id ia in t h i s e x p e r im e n t.
presence
of
production
significantly
inoculation.
both
At
pathogens
inoculated
all
striiform is
R j,
the
pycnidia
with
cultivars
that
showed
together
though
t h e 0.05 l e v e l .
seemed
only
to
in
fewer
decrease
Lemhi
plants
pycnidia
pycnidial
3 2 days
after
inoculated
(0.5)
The
than
with
plants
M. g r a m i n i c o l a o n l y . I n t h e a n a l y s i s o f
wh e n p l a n t s
(0.2 and 0. 3) ,
time,
to
Wampum a n d L a k h i s h
comparison to the s u s c e p tib le
and B a a r t as d e t e r m i n e d
Test
negative.
of
and
variability
pycnidia
pycnidia in
was
£L_ g r a m i n i c o l a .
Cultivar
presence
cold
s t r i i f o rmi s
necrotrophic
produce
interaction
where
there
were
colonized
differences
were
fewer
with
not
plants
both
with
pathogens
significant
at
n
Tabl e 9.
R atio
of p la n ts
bearing
pycnidia
of
My o p s p h a e r e 1 1 a g r a m i n i o o l a t o t o t a l p l a n t s i n
the
presence
and
absence
of
Z t i s r c IvJ i i a
sbrllform ip.
Cultivar
D ays a f t e r
23
2/
inoculation
25
32
Lak. Ps.
Lakhish
3/
0 .0 A
0 .0 A
.0 . 0 A
0 .0 A
0.1 A
0 .2 A
Anz. P s .
Anz a
0 .0 A
0 .0 A
0.0 A
0 ^0 A
0 .0 A
0 .0 A
L e m. P s .
Le mhi
0.1 A
0 .2 A
0.2
0.3
A
A
0.5
0.9
B
A
Baa. P s .
Baart
0 .2 A
0 .0 A
0 .5 A
0.4 A
0.7
0.9
A
A
Warn. P s .
Wampum
0.0 A
0 .0 A
0.1 A
0.4 A
0.2 A
0.2 A
0.3
43
0.3
59
LSD
C. V.
0.2
24
5%
C o mp a r i s o n u s i n g o r t h o g o n a l
All
All
c u l . Ps .
cultivars
0.2
0.2
A
A
0.6
0.6
contrast:
A
A
0.3
0.4
A
A
I / R a t i o w a s c a l c u l a t e d by d i v i d i n g t h e n u m b e r o f p l a n t s
w i t h o b v i o u s p y c n i d i a by t h e t o t a l n u m b e r o f p l a n t s i n
the treatm ent.
2 / I n d i c a t e p r e s e n c e o f Z 1. s t r i i f o r m i s .
3 / P a i r o f v a l u e s v e r t i c a l l y f o l l o w e d by t h e s a m e l e t t e r
a r e No t s i g n i f i c a n t l y d i f f e r e n t a s d e t e r m i n e d by LSD ( P <
0.05) or T - t e s t
( P < 0.05) in
case of o r th o g o n a l
comparisons.
There
affected
by
was
a
relationship
g r a mi n i o o l a
between
and t h e
the
number o f
leaf
area
p lan ts
with
J
48
pycnidia
was
wh e n
analyzing
positive
inoculation
and
associated
with higher
leaf
area
this
JL*. S - t r l i f o r m i s
inoculated
other
the
pathogens
The
results
and
pathogen.
32 days
after
P < 0.05) and
by Mi, g r a mi n i c o l a i s
of
pycnidia.
were
R l g r a mi n i c o l a
treatment
inoculated
indicate
to
collected
therefore
was
when
b e h a v io r
they
were
which had been c o l o n i z e d f i r s t
Different
responses
that
these
at
the
time
one or t i m e
cultivars
pathogens.
analyzed
combinations
The
separately
used
by
of
two.
have
information
for
each
of
cultivars.
Lakhish
Necrosis
0 c cure d
and
e x p e r i m e n t was t o s t u d y t h e
different
Cultivar
affected
production
onto tis s tie s
the
four
23
relationship
experiment £
The a i m o f
the
This
( r ^ = 0.6 a n d 0 . 5 , r e s p e c t i v e l y ,
that
of
results.
significant
indicates
Interaction
all
in
Compar ed t o
chlorosis
plants
the
in the f i r s t
w ithout
control
of
leaf
tissue
inoculation
significant
eventually
(Table
differences
10).
appeared
t w o d i s e a s e a s s e s s m e n t s o f t r e a t m e n t 00 RO
and t h e
first
include
Rl
graminicola
and
disease
assessment
of
SO HO,
inoculation
(SO 00)
did
not
nongreen area of Lakhish
as
cause
at
both
tim e
significantly
compared w ith
the
of which
I.
Rl
greater
control,
49
which
confirm ed
communication)
particular
Table
a
that
isolate
10.
previous
Effect
this
report
cultivar
was
( Ey a I ,
personal
resistant
to
this
o f IL, g r a m i n i c o l a .
of
d i f f e r e n t inoculum c o m b in a tio n s of
a iia m ia ia a la . and f
s t r i i f o r m i s on n o n g r e e n a r e a , r u s t s e v e r i t y a n d
l e a f dry
weight
of c u l t i v a r Lakhish.
Nongreen a re a
%
Days a f t e r in o c u .
Treatm ent
Code
21
P u c c in ia s t r i i f o r m i s
s e v e rity
%
Days a f t e r in o c u .
-
Leaf
d ry w e ig h t
mg.
26
31
21
30
65
-
-
-
43
31
60
—
—
—
46
64
26
31
I/
00 00
15
SO 00
29
2/
00 RO
38 0
49 O
SO OR
32
36
OS RO
14
37
47
14
37
47
52
SO RO
37 0
39
61
19
14
20
54
OS OR
9
37
62
-
-
-
44
20
61
19
27
17
20
31
69
32
38
22
40
21
10
LSD
C.V.
-
38
-
55
64
49
71 s
-
-
49
I / F i r s t two c h a r a c te r s in d ic a te p re sen c e (S) o r absence (0) o f
M. g r a m i n i c o l a i n o c u l a t e d i n tim e I o r tim e 2. S eco n d tw o
c h a r a c t e r s i n d i c a t e p r e s e n c e o r a b s e n c e o f £*. s t r i i f o r m i s
in o c u la te d i n tim e one o r tim e two.
2/
S ig n i f ic a n tl y d i f f e r e n t from 00 00 ( c o n t r o l ) a s d e te r m in e d
by LSD (P < 0 .0 5 ).
As i n i n t e r a c t i o n
area
affected
Lakhish
experiment
by Z ju s t r i i f o r mi s
tended
to
be
less
A, t h e a m o u n t o f l e a f
(SO HO) i n t h e
when
both
cultivar
pathogens
were
50
inoculated
together
s t r i i f o r mi s
alone,
n .is.fi.l.s, a t
significantly
at
(Table
time
modify
infected
have
been
to
a
compared
Th e
the l e a f
in
OS
HO)
area affected
the
leaf
with
inoculation
(treatm ent
and s p o r u l a t i n g
due
one
10).
two
T h e r e was a c h a n g e
rust
time
K
ju
not
by r u s t .
dry w e ig h t
effect
of
did
of
Lakhish leaves.
sequestering
p.
stripe
T h i s ma y
induced
by
P.
s t r i i f o r mi s . Th e l e a f d r y w e i g h t s r a n g e d b e t w e e n 43 a n d
7I
mg , w i t h t h e l o w e s t f i g u r e s b e i n g t h e c o n t r o l a n d t h e
M.
graminicola
treatments
and
the
highest
f r o m i n o c u l a t i o n w i t h £*_ s t r i i f o r m i s
noted
that
the
moderate
figures
o n l y ( 0 0 HO).
susceptibility
being
It
wa s
t o Z*. s t r i i f o r m i s
»
of
Lakhish
increase
of
the
(00
o f 68
leaf
indicating
weight
that
and
graminicola.
P.
dry
of
percentage
was
striiform is
an
in
11
the
the
are
In
were
found,
the
the
weight
only
a greater
weight
did
of
27
between
absence
alone
shown i n
presented.
leaf
interaction
dry
are
a
SO RO w a s
caused
leaf
as
However t h e i n c r e a s e
graminAno l a
calculations
differences
control.
JLi . s t r i i f o r m i s .
changes
Table
expressed
treatm ent
there
weight.
significant
In
was
over the
%
g r a mi n i c o l a
leaf
R0)
%
£L.
of
M.
increase
in
not
cause
leaves.
The
A p p e n d i x T a b l e 20.
areas
Though
affected
no
treatm ent
by
significant
of
both
£Lt.
51
Table 11.
E f f e c t of d i f f e r e n t inoculum c o m b in a tio n s o f
EXS.fi.s£hae rg„lJL3. g r a m i n i c o l a a n d £ u c c i n i a
s t r i i f o r m i s on l e a f a r e a a f f e c t e d and p y c n i d i a
p r o d u c e d by Ht g r a m i n i o o l a on L a k h i s h .
le a f area a ffected
M. g r a m i n i o o l a
%
D ays a f t e r
Treatment
Code
by
inoculation.
Pycnidia production
Ratio I/
D ays a f t e r
inoculation.
21
26
31
21
26
31
SO 00
29
31
60
0 .9
0 .7
0 .6
SO OR
32
36
55
0 .7
0 .2
0 .6
SO OR
I8
25
41
0 .7
0 .5
0 .3
LSD
C. V.
21
38
17
I8
25
17
0 .3
35
0 .4
24
0 .3
30
2/
I / R a t i o = Number o f p l a n t s w i t h p y c n i d i a / t o t a l n u m b e r
of plants in the experim ent.
2 / F i r s t tw o c h a r a c t e r s i n d i c a t e p r e s e n c e (S) o r
a b s c e n c e (0) o f
M. g r a m i n i o o l a i n o c u l a t e d i n t i m e o n e
o r t i m e t wo. Se c o n d
two c h a r a c t e r s i n d i c a t e p r e s e n c e or
a b s e n c e o f Ht
s t r i i f o r m i s i n o c u l a t e d i n t i m e one o r t i m e
two.
M.
graminioola
time
leaf
one
a n d Ht
(SO RO)
striiform is
tended
to
cause
a r e a w i t h symptoms a t t r i b u t e d
inoculated
together
at
decreased
amounts
of
t o Ht g r a m i n i o o l a . The
m a x i m u m n u m b e r o f p l a n t s w i t h p y c n i d i a w a s o b s e r v e d 21
days a f t e r
inoculation.
This was p o s s i b l y t h e r e s u l t
of
t h e l o n g e r de w p e r i o d r e q u i r e d f o r t w o i n o c u l a t i o n s .
It
h a s been o b s e r v e d t h a t when t h e l e a v e s w e re s o a k e d w i t h
water,
the amount of
tissue
affected
by R t g r a mi n i o o l a
52
and
the
(Eya l
number
of
personal
assessments
plants
find
the
fewer
Cultivar
larger
plants
Anz a
amounts
Significant
treatm ents.
inoculated
cause
differences,
However,
the
the
same
a significantly
pathogens
to
were
disease
ma de
pycnidia
n e c ro s is
compared
area
of
of
both
after
inoculated
control,
the
d is e a s e
pathogens
OS OR)
nongreen le a f
days
on
the
most
did
area,
not
with
inoculation.
area affected
assess
to
(SO HO a n d
greater
21
in
presence
time
The a m o u n t o f l e a f
difficult
later
12).
t h e e x c e p t i o n o f SO HO,
was
of
the
increased
pycnidia.
nongreen l e a f
at
In
both
This could ex p lain the tendency
with
(Table
were found f o r
pycnidia
comuni c a t i o n ) .
c o u n t s more d i f f i c u l t .
to
with
by Z j. s t r i i f o r mi s
cultivar
Anza.
separately
Wh e n
( SOOO a n d
the
00R0),
s y m p t o m s w h i c h a p p e a r e d w e r e p r e s u m e d t o be c a u s e d by t h e
organism
inoculated.
However,
together,
one c o u l d no t
with
discrim inate
both
pathogens
ho w m u c h o r w h a t
t y p e of symptoms b e lo n g ed t o whi ch p a th o g e n s i n c e
necrosis
appears
to
Furthermore, there
P.
S l J l l i Z f i X f f l Z&
g r a mi n i c o l a
were
together
have
been
no
change
was
(pustule
(pycnidial
in
the
caused
in
the
production)
production)
s a me l e a f .
by
similar
both
behavior
and
when t h e
/
fungi.
of
or
the
Mj .
pathogens
53
Table 12.
Effect
of
d i f f e r e n t inoculum com binations of
a r a m l a l f l f l l a and z a s s l a l a
s t r i i f o r m i s on n o n g r e e n a r e a , r u s t s e v e r i t y , a n d
l e a f , dry..
weight
of
cultivar
An z a .
Nongreen a re
Puccinia s t r i i f o r m i s
Leaf
severity %
dry w e i g h t
Days a f t e r in o c u la tio n . Days a f t e r i n o c u l a t i o n .
mg
T reatm ent ________________:________
N o.Code
21
26
31
21
.26
31
%
I/
00 00
12
2/
24
70
63 O
87
—
—
—
43
SO 00
44 O
00 RO
53 O
59 O
89
53
59
89
44
SO OR
34 {$
62 8
88 o
—
—
—
47
OS RO
33 8
49 8
85 0
—
—
—
43
SO RO
44 O
39
82
—
—
—
44
OS OR
12
48
86
—
—
—
46
LSD
C.V.
20
61
19
27
17
20
45
21
10
I / F i r s t two c h a r a c te r s in d ic a te p re sen c e (S) o r abscence (0) o f
M. g r a m i n i c o l a i n o o u l a t e d i n t i m e one o r t i m e t w o .S e c o n d tw o
c h a r a c t e r s i n d i c a t e p re s e n c e o r a b se n c e o f Zl s t r i i f o r m i s
in o c u la te d i n tim e one o r tim e two.
2 / S i g n i f i c a n t l y d i f f e r e n t t o CO CO as d e te r m in e d by LSD, P <
0 .0 5 .
* ;
Al
54
Anza
was
a lriifa rm ia .
resistant
(Table
differences
in
the
sporulation
of
JLt
explain
why
Also t h e r e
12).
the
There
leaf
dry
no
in
the
changes
Bozeman
isolate
were
significant
no
weights.
s t r i i f o r mi s
no i n c r e a s e
were
to
in
Th e
in
this
leaf
dry
the
leaf
of
absence
cultivar
weight
weights
P.
of
could
occurred.
of
plants
i n o c u l a t e d w i t h Mj . g r a m i n i c o l a .
Results
obtained
for
the
w i t h Mj . g r a mi n i c o l a
at
13.
lower
Significantly
affected
by
Mj .
inoculated
g r a mi n i c o l a
alone
assessment
dates.
by t h e
interaction
and t h e
le a f
of
20
six
dry we igh t
of
observed
formation
may
in
of
one
the
leaf
i;n T a b l e
area
were
with
JEj .
HO)
than
M.
two
disease
(SO
first
t h e method o f a s s e s s m e n t
between the
the
total
symptoms
analysis
n o n ,g re e n
af
leaf
the
area
determinations.
with
pycnidia
of 2/18.5
21
caused
days
cultivar.
the
In
increased
C on Anz a t o
after
Cold t e m p e r a t u r e s
have
this
in
presented
p ath o g en s, the
plants
percent
SO OR.
time
since
lim it e d , to
regime
days
00)
Anza i n o c u l a t e d
com bination
discrim ination
temperature
treatm ent
at
different
The n u m b e r
c o ld
amounts
However,
was
are
In
(SO
used did not allow
caused
t im e one
I
s t r i i f o r mi s
cultivar
the
a ma xi mum
inoculation
in
a n d a dew p e r i o d o f
unexpected
the
in
treatment
pyc'nidial
SO OR,
once
55
again a decrease
was
observed.
produced
Table
in
13 •
in
There
the
number of
were
very
%
pycnidia
pycnidia
per
leaf
An z a .
l e a f a re a a f f e c te d by
M. a ra m in ic o la
P y cn id ia p ro d u c tio n
R atio I /
Days a f t e r in o c u la tio n
Treatm ent
Code
21
26
31
2/
Days a f t e r in o c u la tio n
21
26
31
3/
63
a
87
0 .0
0 .0
0.0.
34
62
O
88
0 .2
0.1
0 .0
14
39
82
0 .0
0.1
0 .0
17
18
25
17
0 .3
35
0.4
24
0 .3
30
SO 00
45
SO OR
SO OR
t
few
with
E f f e c t of d i f f e r e n t inoculum c o m b in a tio n s of
EX£S.a.£Jh.&£.r S-JLLa .gnsffi A n i s s l a
a n d Z s c s ifiA a
s t r i i f o r m i s on l e a f a r e a a f f e c t e d a nd p y c n i d i a
p r o d u c e d by IL. g r a mL n i c o l a o n c u l t i v e r A n z a .
'
LSD 5
C.V.
plants
21
38
Cf'
'
I / R a tio = Number o f p l a n t s w i t h p y c n i d i a / t o t a l num ber o f ■
p la n ts .
2 / F i r s t two c h a r a c te r s in d ic a te p resen ce (S) o r abscence (0) o f
M. a r a m i n i c o l a i n o c u l a t e d i n tim e one o r tim e tw o . S econd tw o
c h a r a c t e r s i n d i c a t e p r e s e n c e o r a b s e n c e o f JE*. s t r i i f o r m i s
in o c u la te d i n tim e one o r tim e two.
3 / s i g n i f i c a n t l y d i f f e r e n t to SO HO a s d eterm in ed by LSD,
P < 0 .0 5 .
56
Cultivar
L em hi ( T a b l e
Disease
greater
on t h e
the
( 25%)
treatm ents
amounts
control
control
I i|) .
of
g e n erally caused s i g n i f i c a n t l y
nongreen
(00 00) .
leaf
area
Thirty-one
than
were
days a f t e r
present
inoculation
showed a lo w er amount of nongreen l e a f are a
than Lakhish
a n d A n z a (65% a n d 70% r e s p e c t i v e l y ) .
The p r e s e n c e o f a n i n t e r a c t i o n
b e t w e e n p a t h o g e n s o n L e mh i
t
was
demonstrated
s t r i i f o r mis
in
when
the
both
significantly
pathogens
were
compared w ith
P. s t r i i f o r m i s a l o n e
respectively).
T h e re
leaf
area affected
was i n o c u l a t e d
This
was
Lemhi
showed
when
to
at
time
because
infection
was t h e
two as
d is e a s e
inoculations
(SO R0)
lower
amount
compared w ith
older
pathogen
time
tissue
of
one.
was
less
study
that
by Z_«_ s t r i i f o r m i s .
only
Arami n i c o l a
o f Z*.
( 0 0 HO) (34% a n d 6 4%
by P. s t r i i f o r m i s w h e n t h i s
cultivar
a nonsignificant
$L-
amount
together
was a s i g n i f i c a n t l y
possibly
susceptible
lower
decrease
(SO
there
00)
were
was
in
this
(4
%)
in
leaf
inoculated.
significant
weight
In
most
increases
in
le a f weight
o f f r o m 22% (SO OR) t o 84% (OS HO) ( A p p e n d i x
Ta b l e 2 0
The
).
exemplified
interaction
by a g r e a t e r
between
increase
in
p l a n t s were i n o c u l a t e d only w ith r u s t
both
pathogens
were
inoculated
pathogens
leaf
Weight
was
when
( 0 0 HO) t h a n w h e n
together
( SO
HO) .
57
Table
14.
E f f e c t of d i f f e r e n t inoculum c o m b in a tio n s of
Mz£<2. s £ h a s . £ s . i i s . a z a m i a i o a i a
a n d Z n s .s if i.iS :
s t r i i f o r m i s on n o n g r e e n a r e a , r u s t s e v e r i t y and
leaf
dry
w eight
of
c u ltiv a r
Lemhi.
Nongreen a re a
P u c c in ia s t r i i f o r m i s
Dry
s e v e rity %
, l e a f w eig th
Days a f t e r in o c u .
mg
%
Days a f t e r in o cu
T reatm ent
Code
21
26
31
21
26
31
25
-
-
-
65
51 0
79 O
—
_
_
62
50 0
64 C
30
50
64
40 &
66
-
-
2
79
49 0
74 O
25
49
74
119
53 0
75 O
13
25
34
90 5
-
-
19
88 «
31
69
32
38
I/
00 00
I
SO 00
16
I
2/
a
00 RO
30
SO OR
17
OS RO
25
SO RO
26 C
0
I
54
20
61
19
27
17
20
OS OR
LSD
CV.
5 %
a
S
Q
I / F i r s t two c h a r a c te r s in d ic a te
M. g r a m i n i c o l a i n o c u l a t e d i n
c h a r a c te r s i n d ic a te p re se n c e
in o c u la te d i n tim e I o r tim e 2.
2 / S ig n i f ic a n tl y d i f f e r e n t to 00
(P < 0 .0 5 ).
treatment
at
time
in
SO OR,
one.
prevented
leaf
in
Necrosis
abundant
photosynthates
dry
21
10
00 a s d e term in e d by LSD
always caused s i g n i f i c a n t
weight
which
22
40
p re se n c e (S) o r abscence (0) o f
tim e I o r tim e 2 . S econd tw o
o r a b s e n c e o f 2«_ s t r i i f o r m i s
I n o c u l a t i o n w i t h £*_ s t r i i f o r m i s
increases
106 *
with
the
IL- g r a m i n i c o l a
caused
exception
of
wa s
inoculated
by IL_ g r a m i n i c o l a
c o u l d have
sporulation
by £j_ s t r i i f o r m i s .
and
sequestering
of
58
Table
15.
%
Effect
of
d i f f e r e n t inoculum co m b inations of
a ra m iiiia a la
a n d ZiL& .s.±& ia
s t r i i f o r m i s on l e a f a r e a a f f e c t e d and p y c n i d i a
p r o d u c e d by Hi. g r a m i n i c o l a on c u l t i v a r L e m h i .
l e a f a re a a f f e c t e d by
M. g ra m in ic o la
Days a f t e r in o c u la tio n
Treatm ent
Code
P y c n id ia p ro d u c tio n
R atio I /
Days a f t e r in o c u la tio n
31
21
26
31
51 »
79 0
0 .9
1 .0
I .0
17
40
65
0 .9
1 .0
I .0
SO RO
13
29
41
0 .7
1 .0
I .0
LSD
CV.
21
38
17,
18
25
17
0 .3
35
0 .4
24
0 .3
30
21
26
SO 00
16
SO OR
2/
3/
I / Number o f p la n ts w ith p y c n id ia / t o t a l number o f p la n ts i n
th e e x p e rim e n t.
2 / F i r s t two c h a r a c te r s in d ic a te p resen ce (S) o r abscence (0) o f
M. g r a m i n i c o l a i n o c u l a t e d i n tim e one o r tim e tw o S eco n d tw o
c h a r a c te r s in d ic a te p re se n c e o r ab sen ce o f Zl s t r i i f o r m i s
in o c u la te d i n tim e one o r tim e tw o.
3 / I n d i c a t e m eans a r e s i g n i f i c a n t l y d i f f e r e n t t o SO RO a s
d e te r m in e d by LSD, P < 0 .0 5 .
59
M.graminioola
be
affected,
with
than
alone
wh e n
(SO 00) c a u s e d mo r e l e a f
this
pathogen
was
in
a re a
to
combination
P. s t r i i f o r m i s (SO HO) ( T a b l e 1 5 . ) . T w e n t y - o n e d a y s
after
inoculation,
pycnidia.
number
There
of
colonized
most
were
plants
of
the
L e mh i
plants
no s i g n i f i c a n t
with
pycnidia
by £_*_ s t r i i f o r m i s .
had
abundant
differences
after
in the
tissues
Lemhi showed t h e
were
greatest
I
number
of
plants
assessment.
with
period
colonized
utilized
this
the
first
disease
showed
pathogens.
experiment
The
could
longer
have
de w
accounted
of
inoculated
16).
sim ilar
behavior
at
than
leaf
time
that
area
one
interaction
s t r i i f o rmi s
pathogens
pustules,
together.
which in c lu d e d
exhibited
affected
(00
t h a n when i n o c u l a t e d
As i n
to
Lemhi,
with
g r e a t e r nongreen l e a f area in most of the
inoculations
amount
greater
both
this
( Table
significantly
disease
in
by
result.
Baart
OR).
at
T h e r e w a s no d e c r e a s e i n t h e n u m b e r o f p l a n t s
C ultivar Baart
Th e
pycnidia
p y c n i d i a a s was shown i n i n t e r a c t i o n e x p e r i m e n t A i n
tissues
for
with
HO,
OS
at
time
by
by
the
£*.
s t r i i f o r mi s
RO a n d
SO HO)
was
t w o (SO OR a n d OS
experiment
A,
on
plants
inoculated
Also,
leaf
Zt s t r i i f o r m i s
control.
there
weights
inoculated
were
of
at
fewer Zt
with
both
treatm ents
time
one
60
( 0 0 HO, OS HO a n d
treatm ents.
JL*.
OS OR) t e n d e d t o
s t r i i f o r mi s
c aused an i n c r e a s e
3k%
wh e n t h e s e
be h i g h e r
inoculated
in le a f weight
pathogens
of
alone
(00
HO)
compared w ith
86%
were i n o c u l a t e d
than other
together
(SO HO)
(Appendix
Table
Table
E f fe c t of d i f f e r e n t inoculum co m b in atio n s of
H z f i.f i.s .f i.k & s .r e iis
and £ J is ^ ijiia
s t r i i f o r m i s on n o n g r e e n a r e a , r u s t s e v e r i t y a n d
leaf
dry
w eight
of
c u ltiv a r
B aart.
16.
20).
Area nongreen
P u c c in ia s t r i i f o r m i s
%
%
d ry
l e a f w eight
Days a f t e r in o c u la tio n Days a f t e r in o c u la tio n
mg
T reatm ent____________________ _________'
____
Code
21
21
26
26
31
31
I/
00 00
2
0
31
-
-
-
80
81
2/
SO 00
25 0
52 9
77 9
-
-
-
00 RO
36 *
60 9
77 0
36
60
77
SO OR
20
43 9
65 9
0
0
3
OS RO
40 9
72 9
81 9
40
72
81
169 9
SO RO
23 9
43 9
68 9
7
23
36
107 9
58 9
0
0
13
105 9
31
69
32
38
22
40
OS OR
LSD
C.V.
I
I
20
61
19
27
17
20
148 9
88
21
10
I / F i r s t two c h a r a c te r s in d ic a te p re sen c e (S) o r abscence (0) o f
M. g r a m i n i c o l a i n o c u l a t e d i n tim e one o r t i m e t w o . S eco n d tw o
c h a r a c t e r s i n d i c a t e p r e s e n c e o r a b s e n c e o f £*_ s t r i i f o r m i s
in o c u la te d i n tim e one o r tim e two.
2 / S ig n i f ic a n tl y d i f f e r e n t from 00 00 a s d eterm in ed by LSD (P <
0.05).
61
Leaf a reas a f f e c t e d
by M. s n s . f f i . i i i a r e
given in
T a b l e 1 7 . T h e t w o p a t h o g e n s t o g e t h e r a t t i m e o n e (SO HO)
produced
for
a
the
significantly
last
two
disease
S H a ffiiH iS ffiia
alone.
pycnidia
treatm ent
after
( SO
in
inoculation)
lower
as
In
amount
of
iL.
assessm ents
addition,
(SO HO)
fewer
were
compared w i t h
eraminicola
than
for
plants
observed
( 21
BL. e r a m i n i c o l a
with
days
alone
00).
Table
17.
E f f e c t of d i f f e r e n t inoculum c o m b in a tio n s of
H X ffio a a k a s n ffilla s f f ia a ia if f if f iia a n d Z a a a i a i a
s t r i i f o r m i s on l e a f a r e a a f f e c t e d a n d p y c n i d i a
p r o d u c e d by £L. e r a m i n i c o l a on c u l t i v a r B a a r t .
l e a f a re a a f f e c te d by
M. e ra m in ic o la
Days a f t e r in o c u la tio n
%
T reatm ent
Code
21
26
P y cn id ia p ro d u c tio n
R atio I /
Days a f t e r in o c u la tio n
31
21
26
31
2/
I/
SO 00
25
52 0
77 6
1 .0 0
0 .9
I .0
SO OR
20
43
61
I .0
I .0
I .0
SO RO
18
20
32
0 .6
0 .8
0 .9
LSD
C.V.
21
38
17
18
25
17
0 .3
35
0 .4
24
0 .3
30
I / F i r s t two c h a r a c te r s in d ic a te p re sen c e (S) or■ abscence (0) o f
M .e r a m in i c o la i n o c u l a t e d i n t i m e one o r t i m e t w o . S econd tw o
c h a r a c t e r s i n d i c a t e p r e s e n c e o r a b s e n c e o f £*_ s t r i i f o r m i s
in o c u la te d i n tim e one o r tim e two.
2 / s i g n i f i c a n t l y d i f f e r e n t to SO HO as d eterm in ed by LSD
(P< 0 .0 5 ).
62
Interaction
This
the
during snore
assay
presence
inhibition
wa s
of
of
germination
conducted to
bud s p o r e s
test
o f AL. g r a m i n i c o l a
jL_ s t r i i f o r mi s
uredospore
U r e d o s p o r e s o f Z jl s t r i i f o r m i s h a d
inoculated
18
medium
and
only
5
bud-spores
of
S H a ffiiJ 3 .if ifi.la .
comparison,
the
g e rm in a tio n of the
also
was
significantly
present
on t h e
interaction
possibly
%
a l o n e , 16 ? g e r m i n a t i o n i n
M. g r a mi n i c o l a
alone
the hypothesis that
higher
%
in
at
the
time
presence
of the
presence
an
of
orthogonal
inoculated
wh e n b u d - s p o r e s
This
of
g e r m i n a t i o n wh e n
uredospores
indicated
b e t w e e n P. s t r i i f o r mi s
starts
cause
germination.
the
Using
than
membrane.
the
would
were
that
the
a n d M. g r a m i n i c o l a
germination.
(Appendix
Table 21).
Field
observations
, The
natural
Montana i n
was
1 983 w a s v e r y
recorded
striiform is
inoculated
inoculated.
present
spread
in
infection
pertinent
of
striiform is
in
uniform
and
Information
to
i n t e r a c t i o n -between
the
a n d AL. g r a m i n i c o l a . The
and was r e s t r i c t e d
Low r e l a t i v e
this
area
o f AL. g r a m i n i c o l a .
was
t o t h e r o w s on w h i c h i t
wa s
not
latter
P.
pathogen
humidity
were
severe.
B o z e ma n ,
and
cold
favorable
to
temperatures
the
natural
63
In general,
by
on w i n t e r w h e a t s ,
striiform is
present
level
for
in
the
decreased
tissue
the
s t r i i f o r mi s .
(Table
18).
The
A result
separated
decrease
in
infection
type
of
plants
into
the
were
compared t o
number
( 17 t o 7
with
readings
different
no
infection
than th a t
measured
concordant
with
of
recorded
the
on p l a n t s
when r u s t
(62
infected
developed
was
a
susceptible
in
the
to
75
only
in
types
There
and an i n c r e a s e
%)
growth
infection
categories.
plants
disease
taken
those
of
was a l s o
average
c ha m b e r s t u d i e s was o b s e r v e d when r u s t
were
area affected
w h e n JL. g r a m i n i c o l a
o f M-l g r a m i n i c o l a w a s g r e a t e r
.Ej .
leaf
the
number
%)
when
with
rust
presence
of
between
P.
M. g r a m i n i c o l a .
On
spring
S lz iiJ ilfi-H ffilS .
significant
graminicola
genotypes.
the
amount
presence
wheat,
relationship
M-L & Z S f f i i f i i f i f i i S
and
(Table
were
the
19).
The l e v e l s
slightly
higher
was
of
general
trend,
of
natural
£_*. s t r i i f o r m i s
o f M_l g r a m i n i c o l a .
both
compared
The
however,
negative
to
the
a n d M_l
winter
wa s a d e c r e a s e
infection
wh i c h was s i m i l a r
o b ta in e d w ith the w i n t e r wheat.
rust
and
in
in
the
to r e s u l t s
64
Table
18 . Me a n a n d r a n g e o f p e r c e n t a g e o f l e a f a r e a
affected
by
a . i z ± i j f 2. r . m i s. a n d
M y c o s n h a e r e l l a g r a m i n l c o l a on 84 w i n t e r w h e a t
c u l t i v a r s . B o z e ma n 1 9 8 3 .
P a rt I .
P. s t r l l f o r m l s
Mg. p re s e n t.
A
Mean
Maximum
Minimum
P. s t r l l f o r m l s M. g ra m in lc o la
Alone
Ps. p re s e n t. I /
B
__
C
13
37
80
80
0
5
I/
5
40
0
C o rre la tio n s
A vs.
A vs.
C
B
r - 0. 12 ( N o n -s ig n ific a n t )
= 0.5 2 ( s i g n i f i c a n t a t P< 0 .05)
P a rt 2 .
P ercen tag e of th e t o t a l number o f p la n ts
i n each r u s t i n f e c t i o n ty p e .
2/
T reatm ent
P s . and Mg.
P s . on ly
0
R
MR
MS
S
75
62
0
I
7
I
, 11
19
7
17
1/ P s . , Mg. P u c o ln la s t r l l f o r m l s and M v c o s p h a e r e lla
g ra m in lc o la r e s p e c tiv e ly .
2 / O= a b s e n c e o f d i s e a s e , R= r e s i s t a n t r e a c t i o n , MR=
m o d e ra te r e s i s t a n t r e a c t i o n , MS= m o d e ra te s u s c e p t i b l e
r e a c tio n and S= s u s c e p tib le r e a c tio n .
65
Table
19.
Me a n a n d r a n g e o f p e r c e n t a g e o f l e a f a r e a
affected
by
a lr iif a r m ia
and
M y c o s P h a e r e l l a g r a m i n i c o l a on 83 s p r i n g w h e a t
c u l t i v a r s . B o z e ma n I 9 8 3 .
P a rt I .
P. s t r i i f o r m i s
P. s t r i i f o r m i s M. g ra m in ic o la
Mg. p re s e n t I /
a lo n e
Ps. p re s e n t I /
B
C
A
Mean
13
27
39
Maximum
80
90
99
Minimum
0
0
0
C o rre la tio n s A v s . C = -0 .4 3 ( S ig n if ic a n t P< 0 . 0 5 ) .
A vs . B = 0 .7 0 ( S ig n if ic a n t P< 0 . 0 5 ) .
P a rt 2 .
P ercen tag e o f th e t o t a l No. o f p la n ts
i n each r u s t i n f e c t i o n ty p e .
2/
T reatm ent
I/
P s . and Mg.
Ps o n ly
0
R
MR
MS
64
36
1
2
14
12
18
30
S
2
19
I / P s. an d Mg.P u c c in ia s t r i i f o r m i s and M v c o s o h a e r e lla
g ra m in ic o la r e s p e c tiv e ly
2 / 0= a b s e n c e o f d i s e a s e , R= r e s i s t a n t r e a c t i o n , MR=
m o d e ra te r e s i s t a n t r e a c t i o n , MS= m o d e ra te s u s c e p t i b l e
r e a c tio n and S= s u s c e p tib le r e a c tio n .
66
T h e r e was a d e c r e a s e
showed i n f e c t i o n
the
plants
The
plots
the
with
type
i n th e number of p l a n t s which
S ( 19 t o
infection
plastic
type
tarpaulin
2 55 ) a n d a n i n c r e a s e
0 (36 t o 64
w h i c h was
used
%) .
to
cover
( i n o c u l a t e d w i t h M. g r a mi n i c o l a l t o i n d u c e
leaves
som etim es
temperatures.
recorder
was
treatm ent,
To
caused
measure
placed
covered
in
this
the
and
middle
uncovered.
m e a s u r e m e n t wa s made on J u l y 2 2 ,
wind and one i n w h i c h t h e s o i l
before.
A ma x i mu m t e m p e r a t u r e
in
covered
the
treatm ent,
since in susceptible
were i n f e c t e d .
uncovered
amount
of
a
the
The
the
de w on
unfavorably
factor,
in
high
thermograph
row
in
each
tem perature
a day w i t h o u t
rain
had been i r r i g a t e d
or
a day
o f 17 C, w h i c h w a s o b s e r v e d
was
cultivars
not
large
unfavorable
to
rust
amounts o f l e a f
area
The m i n i m u m t e m p e r a t u r e r e c o r d e d i n t h e
treatm ent
(7
C)
of n a t u r a l .spread of
could
explain
the
lim ited
67
DISCUSSION
Wheat
confronted
cultivars
in
with
constraints
many
the
field
w ill
always
usually
be
including
several
pathogenic microorganisms.
S o me p a t h o g e n s h a v e
similar
environmental
and
often
found
diseases
to
if
a
two
single
an outcome
each were
Kt. g r a m i n i o o l a
th e s e
Whe n
on
produce
would oc cu r
with
together.
converge
interact
requirements,
more
therefore,
pathogens
wheat
plant,
different
from
present
and
or
are,
alone.
That
£*. s t r i i f o r m i s .
they
that
is
the
which
case
the
subjects
tritic i
blotch,
the
disease
caused
of
by H jl
g r a m i n i c o l a . i s an i m p o r t a n t wheat d is e a s e i n th o s e
the
ma y
studies.
Septoria
of
and
the
world
where a cool,
vegetative
of w heat,
damage
septoria
portion
caused
in
some
tritici
by
of
of
wet e n v i r o n m e n t
plant
development.
the
blotch
same
areas
is
problem.
a
the
and
world
Sometimes
same p l a n t s
D u b i n , 1983) c o n f o u n d i n g r e s e a r c h
rust
causes
where
the
t wo
( M o r k , 1 9 82;
and c a u s i n g l o s s e s i n
crops.
The r e s t r i c t i v e
favors
of
during
Stripe
P . s t r i i f o r mi s . o c c u r s
d i s e a s e s o c c u r t o g e t h e r on t h e
farmers'
exists
parts
epidemics
of
cool environm ent
stripe
rust
(12 t o
14 C) t h a t
( Z a d o k s , 1979)
and
the
68
ability
of
usually
JLt 8.J b r i l f a r m t o
reduces
econom ically
developed
concurrent
im portant
Intercellular
ramifying
the
mycelia
throughout
tissue
survive
near
wheat
axil
but
move
same e n v i r o n m e n t as
as
rapidly
confined
moisture
M.
to
is
through
the
graminicola
occupy l a r g e
can
areas
of
the
tissue,
first
lesions
the
varied
when
EIL& m illA c SLJLjgi.
cultivars,
exemplified
also
leaf
were
were
observed
o f Anz a r e s u l t e d
by
except
after
leading
one
chlorosis
30
to
days
suspect
Some i s o l a t e s
phytotoxins
leaf
tissue,
the
newly
and grow
in
the
often
remaining
when
free
a d e q u a t e , however,
expand r a p i d l y
(Chester,
and
1944).
used in th e s e s t u d i e s
inoculated
formed
in
with
M.
susceptible
b u t a p p e a r e d i n a " g r e e n i s l a n d " on B a a r t , a
phenomenon
Inoculation
is
that
wheat
they
Pycnidia
pathogens.
penetrated
R ea c tio n s of wheat c u l t i v a r s
were
other
and s h e a t h .
tissues
When m o i s t u r e
cause
of
0 C
P. s t r i i f o r m i s , but does not
tissues
limited.
than
favoring
of le a f
ILt. - g r a mi n i - c o l a c a n i n f e c t
exact
leaf
colonize
leaf,
the
less
development
rapidly
the
at
at
by
others
(Beach,
in a hypersensitive
and
necrosis,
tem peratures
a toxic
but
of
reaction
not
4
1919).
pycnidia
to
1978).
C,
reaction.
o f H t g r a m i n i c o l a a r e k n o wn t o
(Malcolm,
10
The
often
observed
produce
early
69
onset
of
senescence
H ypersensitive
susceptibility
pathogen
to a to x in ,
resultant
d is e a s e
hypersensitive
o f Anz a t h e
two
susceptible
to
that
to e i t h e r
results
pathogens
not
of
susceptible
susceptible
graminioola
the
the
present,
P. s t r i i f o r mis
susceptible
to
no
disease
of
plants
in
part,
by t h e
pathogen
resistant
the
or
case
The i n t e r a c t i o n
dem ostrated
type
(93
in
plants
33
a trend
moderately
symptoms.
could,
was
%)
the
%.
with
on
the
absence
resistant
or
a
of
present in
moderately
with
inoculated
away from
Th e r e d u c e d
showed
Therefore
subsequently
s t r i i f ormis uredospores in the
conidia
either
p a t h o g e n was a l s o
was o n l y
exhibited
toward
affected
wh e n
plants
infection
percentage
reactions
a
and Lemhi .
M. g r a mi n i o o l a . Wh e n t h i s
tissue
best
to
were
consistent.
was
Baart
most
response
of Baart.
was
wheat
be
compatible host-
or both patho gen s as i n
were
cultivars
area
the
may
Mj .
obtained
If
reaction.
An z a ,
a lesser
and
sim ilar
alone.
B aart,
moderately
the
in
more
may r e f l e c t
together,
inoculated
In
toxigenic
as
while
JLl a l r i i f a r m i a
inoculated
the
a
wa s o b s e r v e d w i t h i n f e c t i o n
When
of
be
re sista n c e ,
interactions
t o x i n , as
was
may
Mj .
with
moderately
even
further
germination
o f Z jl
p r e s e n c e o f Mj . g r a m i n i o o l a
account
for
this
result.
70
However,
cross
resistance
mechanisms
are
possibilities.
other
protection
and
or
in
nutrient
resistance
unknown
mechanism
of
The
to
the
of
depletion
or
interaction
could
by
observed
substrate
the
was
by
the
general
imbalance
between
have
JEjl s t r i i f o r mi s
triggered
Th e r e s u l t
destruction
induction
Mjl s r a . a i s . i s f i . l s .
increase
g r ami n i c o l a.
by
due
been
to
presence
simply
P.
an
s ome
of
M.
premature
necrotrophic
M.
graminicola.
In
the
resistant
cultivar
graminicola inoculation,
most of
a resistant
to
reaction
o f Mi. g r a m i n i c o l a
%) ,
but
observed
decreased
ILl. f i . l r i i f f i . r a i a .
in eith e r
ability
to
Anz a due
to
the
reported
could
modify
secondary
sporulated
case.
produce
(1974)
Lepeuple)
(R)
freely
wh e n t h e
this
on a
of Lemhi p l a n t s
The
p re se n c e
slightly
production
the
in the
of
In
resistant
striiform is.
presence
of
this
(74
was
not
cultivar
g r a mi n i s
M_«_ s r a . a i r i £ . o l s .
wheat
the
Brokenshire
of E rv siP h e
case,
resistant
as
a
Mjl s r a m i n i-C P .la
cultivar
( Elite
p o w d e r y m i l d e w f u n g u s wa s p r e s e n t .
With a p o s t - i n o c u l a t i o n
%
( 7 8 %) s h o w e d
percentage
pustule
incidence
pathogen.
plants
M.
T h e r e w a s no m o d i f i c a t i o n i n
presence
the
the
w ithout
striiform is.
pycnidia
that
Anzaj
inoculated
dew p e r i o d o f t h r e e
with
days,
M. g r a mi n i c o l a
85
alone
71
produced pycnidia,
a fte r
while
in o cu latio n
45
of
%
plants
w ith
produced pycnidia
a ram laiaala
and
P.
s t r i i f o r m i s . Wh e n t h e s a m e c u l t i v a r w a s s i m u l t a n e o u s l y
inoculated
period,
with
the
difference
was l e s s e n e d .
was
both pathogens,
This
associated
t r e a t m e n t , 93
21
days
%
after
inoculated
organism,
alone
suggested
with
a n d 70
of
the
that
Results
the
to
Pasteur
plants
1981;
plants
when
the
pycnidia
production
longer
produced
ILl
g r a mi n i c o l a
with
the
wet
pycnidia
stripe
was
rust
1979
susceptible
moderately
(Daly,
by r u s t
mor e
and
energy
wheat
Cg/ C^
alter
toward
pathogen
infected
and
that,
cultivar,s Baart
Lakhish,
There
result
the
in a
and
abolition
is
evidence
phloem t r a n s p o r t
MacDonald
susceptible
which
ratio
I 976).
work i n d i c a t e
the
P r o d u c t i o n of u r e d o s p o r e s
a drop i n
effect
moving t o
of th is
and
production for Zl s t r i i f o r m i s
demands o f
colonized
Mares
for
to another.
respiration,
materials
In
mechanisms which p e r p e t u a t e
higher
related
the
with
pycnidial
combination
and u r e d o m y c e l i a
is
of
plants
wetting.
production
cycle
in
that
of the
%
and i n
from one l i f e
rise
leaf
of
respectively.
uredospore
s o me
number
inoculation,
Pycnidial
are
in
f o l l o w e d by a s i x d a y dew
areas
with
( Me d g e n ,
Strobel,
1970).
f o r P . s t r i i f o r mi s ,
and
Lemhi
presence
and
for
of s t r i p e
72
rust
increased
respectively
leaf
. The p r e s e n c e
and s t r i p e r u s t
only
34
,
%
pathogens
w eight
were
and
%
27
of
86
%,
64
septoria
and
%
tritic i
respectively,
%,
inoculated
the
significantly
by
68
%,
blotch
c a u s e d an i n c r e a s e i n d ry l e a f w e i g h t of
40
of
dry w eig h t
at
the
re s is ta n t
modified
s a me
time.
c u ltiv a r
by i n f e c t i o n
when
both
The l e a f
Anza
dry
was
not
with
either
pathogen
H e n d r i x e t a l . ( 1 965) r e p o r t e d t h a t
stripe
r u s t was
a l o n e or w i t h b o th a t t h e same t i m e .
more
harmful
wheats.
effect
This
than
mechanical
result
is
which d e p riv e s
moving them t o
In t h i s
consistent
nutrients
sporulating
work l e a f
possible
sequestering
of
the
the
that
pathogens
effect
caused
the
This in f o r m a t i o n
infection
Tomerlin
methods
et
physiology
effect
al.
of
occurs
as
the
by
parts
by
dry w e ig h t.
Furthermore, i t
by t h e
rust
proposed
without
the
total
be l e s s
the
effect
damage
than
alone.
a danger in using m u l t i p l e
by K i l p a t r i c k
further
interactions.
deprivation
interrupted
rust,
could
suggests
(1984)
sequestering
ILi. s t r i i f o r mi s
host
by s t r i p e
spring
by
ILl g r a m i n i c o l a
caused
in
the
from o t h e r p l a n t
area a ffe cted
since
effect
with
in
tissues.
wa s c o r r e l a t e d w i t h i n c r e a s e d
is
defoliation
of
If
(1981)
research
the
nutrients
and
on t h e
sequestering
from
other
73
plant
tissues,
different
healthy
these
plant
behavior
toward
s t r i i f o r mi s
cultivar
Anz a w a s
area
weight
Th e d r y
not
colonized
significantly
leaf
first
diseased
in
fungus
in the
inoculated
control
to
were
not
1 9 7 2) h a v e
uredospores
reduced
resistant
to
the
amount
heavier
tritici
of
was
blotch
disease,
than
non-
was f i r s t
s t r i i f o r mi s
heavier
that
than
authors
those
from
was
non-
rust
which
this
of s t r i p e
study.
caused
could
observed in
a
explain,
tissues
rust
The p r e s e n c e
decrease
in
part,
colonized
in
the
by b o t h
e x p l a n a t i o n m i g h t be t h a t s i n c e
organisms are stomatal
may
( M a c k o , I 977 a n d
germination
observed in
germination
openings
the
before
noted in the
p a t h o g e n s . An a l t e r n a t e
stomatal
of
plants.
wa s a l s o
stripe
P.
each
. Leaf w eight
were
Mj - .&£..&m i l l !.£.5.I s . b u d - s p o r e s
uredospore
by
for
r u s t was t h e s o l e
leaves
leaves
The g r e a t v a r i a t i o n
both
a
case of c u l t i v a r s L akhish,
When s e p t o r i a
the
leaves
weight
by e i t h e r
occurring,
inoculated,
of
compared
was d i f f e r e n t
according
altered
controls.
established
Sharp,
as
show
area affected
changed
L e m h i a n d B a a r t . Wh e n s t r i p e
the
probably
pathogens
between l e a f
and dry l e a f
studied.
cultivar
or
will
tissues.
The r e l a t i o n s h i p
leaf
parts
occur.
penetrators,
The
poor
competition for
germination
of
Z jl
74
SirjLtfOTffiis. i n
survival
the
presence
mechanism
germ inate
un til
A lternatively,
directly
for
o f H1. g r a m i n l c o l a
the
uredospores
su itab le
the
conditions
uredospores
could
or
pathogen
by o t h e r
field
corroborate
compound(s)
have
not
present.
been i n h i b i t e d
produced
in
it
possible
s ome
observations
of
studies.
In
naturally
infected
found t h a t
the
the
1983»
results
the
obtained
Bozeman
with
presence
was
results
were
Measuring
sim ilar
flag
that
leaf
to
a decrease
graminlcola.
the
analysis
separating
of s u s c e p t i b l e
had
possible
of
the
the
presence
o f s ome g e n o t y p e s
(I 944)
caused
These
by JEj . s t r i i f o r mi s
the
were
area
also
plants
a reduced
type
been i n o c u l a t e d
that
in
tissues
genotypes,
infection
blotch
were
by l e a f f u s t .
affected
occurred
M.
fields
tritici
to
t h o s e fo u n d i n Bozeman i n 1983.
areas
s t r i i f o r m i s . when t h e
without
host-
laboratory
P. s t r i i f o r mi s . C h e s t e r
of s e p t o r i a
P.
In
the
from
Montana
a decrease in the le a f area a ffe cted
tissue
are
do
interface.
With
plants
which
be a
by a p r o d u c t o f t h e m e t a b o l i s m o f H=, g r a m i n l c o l a
(toxin)
showed
might
as
affected
infected
a
by
with
population,
number
of
plants
was o b s e r v e d when t h e s e
with
of
both
H*.
does induc e
pathogens.
gramin i cola
It
in
is
the
a " p s e u d o r e s i s t a n c e 1*
75
reaction
t o .Rjl s t r i i f o r m i s .
Concluding remarks
By u s i n g s e e d l i n g s
of
cultivars
and B a a r t the i n t e r a c t i o n
was
profiles
the
favorable
interaction
compete
for
measured
disease
and
to
rust
the
stripe
of
septoria
the
two
s a me
separately
peculiar
striiform is
infected
more
that
have
in
the
since
they
pathogen is
even
treatm ents
longer
with
than
biotrophic
le a f
sporulating
no
equivalent
inoculation.
of
together.
l e a v e s , a n d a b l e s t hem t o s u s t a i n l i f e
shape
favor
symptoms
the
dry
also
The
When e a c h
of
a n d M.
blotch.
exists
system
an i n c r e a s e
seedlings
tr itic i
produces
Le mh i
Tem perature
development
two p a t h o g e n s o c c u r
pathogenic
causes
studied.
tissue.
each
An z a ,
s t r i i f o r mi s
pathogens
plant
t h a n wh e n t h e
The
their
of
between
observed
developm ent
Lakhish,
plants
P.
weight
of
pustules
on
and norm al
in
control
N ecrotrpphic
M.
g r a mi n i c o l a c a u s e s a d e c r e a s e i n t h e l e a f a r e a a f f e c t e d
by
stripe
weight.
rust,
diminishing
also
its
effect
on
leaf
76
CONCLUSIONS
1.
P. s t r i i f o r mi s
wheat
that
a n d M. g r a mi n i c o l a a r e p a t h o g e n s o f
can
colonize
the
same
tissu e
simultaneously.
2.
3.
The
presence
the
leaf
Th e
pustules
area
Kl g r a m i n i c o l a
affected
caused
a decrease
in
by JL»_ s t r i i f o r m i s .
color
from
y e l l o w - o r a n g e t o b l a c k - b r o w n i s h wh e n t h e y w e r e
close
to
4.
of
lesions
Presence
decrease
o f JLt s t r i i f o r mi s
changed
o f Kl g r a m i n i c o l a .
of
in
Kl
possibly
infection
of Zl s t r i i f o r m i s . There
more p l a n t s t h a t a p p a r e n t l y
s t r i i f o r mi s
when
caused
both
escaped in fe c tio n
pathogens
were
a
were
by P .
inoculated
together.
5.
Conidia
of
Kl
g r a mi n i c o l a
germination of Zl s t r i i f o r m i s
6.
caused
inhibition
uredospores.
Anza s h o w e d f e w p y c n i d i a i n r e s p o n s e
isolate
low
result.
to th e Oregon
o f M. g r a m i n i c o l a a n d o n l y w h e n e x p o s e d t o
temperature
presence
of
of
Zl
and a l o n g
s t r i i f o r mi s
period
did
of
not
time.
The
change
this
77
7.
With
one
infected
8.
dew
period
hours
at
10
C,
Lemhi
a g r e a t e r number of p l a n t s w i t h
p y c n i d i a t h a n wh e n
P. striiform is
wa s a l s o
in the
If
were
the
tissues
Lemhi
toward the
a
seedling
s a me
by
time
and B a a r t t h a n i n
and
resistant
by n e c r o t r o p h i c
cultivars
Baart
co lo n izatio n
occurred
increases
in
in
&»_ g r a mi n i c o l a
was
new
by
and
P.
tissues
dry
did
were
smaller
weight
not.
Wh e n
together
at
than
that
of
P.
the
caused
separately.
infection
weights
tissue.
leaf.
the increase
striiform is
leaf
first
a n d 1L, g r a m i n i c o l a
Zi. s t r i i f o r m i s
dry
the
caused
leaves.
striiform is
only
of
.Li. s t r i i f o r mi s
colonized
reduced
This
b ase
present
susceptible
showed
s t r i i f o r pii s .
10.
72
w i t h AL. g r a m i n i c o l a a l o n e t e n d e d t o e x h i b i t
IL. ££.5.SliILijaAjLa.,
9•
of
of
the
Anz a .
the
caused
greater
susceptible
moderately
increases
cultivars
susceptible
in
Le mh i
Lakhish
78
LITERATURE CITED
Anonymous.
1983.
Nomenclature-Septoria diseases
c e r e a l s . P h y t o p a t h o l o g y news. 17:77-84.
of
A d l a k h a , K. L . a n d S . P. R a y c h a u d h u r i . 1 97 5. I n t e r a c t i o n
b et we en H e l m i n t h o s p o r i u m s a t i v u m and wheat mosai c
s tre a k virus. Pflkrank. 4/75:201-206.
A u s t , H. J . a n d B. H a u . 1 9 8 1 . I n f l u e n c e o f c o m p e n s a t i v e
e f f e c t s o n t h e l a t e n t p e r i o d o f £e.j3£o iLia. n o d o r u m.
Z e its c h rift
fu r
P fla n z e n k ra n k h e ite n
und
P f l a n z e n s c h u t z 88: 6 5 5 - 6 6 4 .
B a h a t , A . , I . G e l e r n t e r , M. B. B r o w n a n d Z . E y a l .
1980.
F a c t o r s a f f e c t i n g th e v e r t i c a l p r o g r e s s i o n of
Septoria leaf
blotch in short s ta tu re d wheats.
P hytopa thology 70:179-184.
B e a c h , W. S.
1919.
B i o l o g i c s p e c i a l i z a t i o n i n t h e genus
s e p t o r i a . A m e r i c a n J o u r n a l o f B o t a n y . VI ( 1 ) : 1 - 3 3 *
Benedict,
W. G.
1971. D i f f e r e n t i a l e f f e c t o f l i g h t
i n t e n s i t y o n t h e i n f e c t i o n o f w h e a t by S e p t o r i a
i n djt i .e.i. De s m . u n d e r c o n t r o l l e d e n v i r o n m e n t a l
conditions. Physiol. Plant Pathol.
1:55-66.
B e n s a u d e , M a t h i l d e . 1 9 2 9 . N o t e s on w h e a t d i s e a s e s i n
Portugal.
B o l m.
Soc . B r o t e r i a n a
6 ( S e r . 2 ) : 1-44.
( A b s t r . R e v . A p p l . Myc o l . 8 : 6 3 7 - 6 3 8 . )
Bird,
P a u l i n e M. a n d J . R i d e . 1 9 8 1 .
The r e s i s t a n c e o f
wheat to S e o t o r i a no d o ru m fu n g a l developm ent in
r e l a t i o n to h o st l i g n i f i c a t i o n .
Physio, Plant
Pathology I 9:289-299.
B r i g g l e , L . W.
1 967.
Morphology of the wheat p la n t in
" Wh e a t a n d w h e a t i m p r o v e m e n t " e d . Q u i s e n b e r r y , K. S.
and R e i t z ,
L.
P. No 1 3 s e r i e s of. A g r o n o m y .
A m e r i c a n S o c i e t y o f Ag r o n o my p p . 5 6 0
B r o k e n s h i r e , T.
1974. P r e d i s p o s i t i o n
Septoria in fection following attack
T r a n s . Br. M y c o l . S o c . 6 3 : 3 9 3 - 3 9 7 .
of
by
w h eat to
Erysiphe.
79
B r o k e n s h i r e , T. 1 9 7 5 . The r o l e o f g r a m i n a c e o u s
t h e e p i d e m i o l o g y o f Se n t o r i a t r i t i c i
PI.Path. 24:33-38.
species in
on w h e a t .
B r o w n , J . S . ; A. W. K e l l o c k a n d R. G. P a d d i c k .
1978.
D i s t r i b u t i o n a n d d i s s e m i n a t i o n o f Mvc o s o h a e r e l l a
Rrami n i c o l a (Fuckel) S c h r o e t e r in r e l a t i o n to the
e p i d e m i o l o g y of s p e c k l e d l e a f b l o t c h o f w h e a t . Aust.
J . A g r . Res. 29: 1 139-1 I 45.
C artw right,
D. W. ' a n d G. E . R u s s e l l ,
G. E . 1 9 8 1 .
Development of P u c c i n i a s t r i i f o r m i s i n a s u s c e p t i b l e
w i n t e r w h e a t v a r i e t y . T r a n s , o f t h e B r i t . Myc o l .
S o c . 76 : I 9 7 - 2 0 4 .
C h e s t e r , K. S. 1 9 4 4 . Low i n c i d e n s e o f w h e a t l e a f r u s t
a s s o c i a t e d w i t h u n f a v o r a b l e l a t e w i n t e r w e a t h e r and
a n t a g o n i s m o f S e n t o r l a t r i t i c i . P l a n t D i s . Re p .
28:280-287.
C h o n g , J . a n d D. E . H a r d e r .
1 9 82. U l t r a s t r u c t u r e of
haustorium development in Puccinia coronata avenae.
Some h o s t r e s p o n s e s . P h y t o p a t h o l o g y 7 2 : 1 5 2 7 - 1 533•
C o m e a u , A. a n d G. J . P e l l e t i e r . 1 976 . P r e d i s p o s i t i o n t o
Septoria
l e a f b l o t c h i n o a t s a f f e c t e d by B a r l e y
Y e l l o w D w a r f V i r u s . C an. J . P l a n t S c i . 5 6 : 1 3 - 1 9 .
Daly,
J . M. 1 976 . T h e c a r b o n b a l a n c e o f d i s e a s e d p l a n t s :
Changes
in
respiration,
Photosynthesis
and
t r a n s l o c a t i o n , in: En cy c lo p ed i a of P l a n t Physiology.
New s e r i e s . 4 : 4 5 0 - 4 7 9 -
D o o d s o n , J . K. , J . G. M a n n e r s a n d A. M y e r s 1 9 6 4 . Some
e f f e c t s o f y e l l o w r u s t ( P u c c l n i a s t r i i f o r m i s ) on t h e
g r o w t h a n d y i e l d o f a s p r i n g w h e a t . An n . B o t . N. S.
( Lo n d ) 2 8 : 4 5 9 - 4 7 2 .
Dubin, J. 1 9 8 3 . O c u rre n c e and i m p o r t a n c e of S e p t o r i a
n o d o r u m a n d &*_ t r i t i c i i n t h e A n d e a n c o u n t r i e s o f
South America. Proceedings of the S e p t o r i a d isea se
w o r k s h o p . B o z e ma n 2 - 4
August. (In press)
E y a l , Z. 1 9 7 1 .
K in e tic of pycnospore l i b e r a t i o n
S e o t o r i a t r i t i c i . ' Can. J . B o t . 4 9 : 1 0 9 5 - 1 0 9 9 *
in
80
E y a l , Z . , A. L . S c h a r e n a n d J .
M. P r e s c o t t .
1 983 .
S e p t o r l o s l s de l a g l u m a S e p t o r i o s l s de l a h o j a .
En f e r m e d a d e s del t r i g o . Metodos y c o n c e p t o s . I n f o r m s
de I n v e s t i g a c i o n
No.211.
Estacion
Experimental
A g r i c o l a de M o n t a n a . 77 pp. P u b l i c a d o e n e s p a n o l p o r
Ci mmyt .
F e l l o w , S . H. 1 9 6 2 .
E f f e c t o f l i g h t , t e m p e r a t u r e and
f e r t i l i z e r o n i n f e c t i o n o f w h e a t l e a v e s by S e o t o r l a
t r i t i c i . P l a n t D is . Rep. 4 6 : 8 4 6 - 8 4 8 .
G h e o r g h i e s , C. 1 9 7 4 . ( C o n t r i b u t i o n t o t h e k n o w l e d g e o f
t h e b i o l o g y o f S e o t o r i a t r i t i c i Ro b . e x D e s m . I .
Germination of pycnidiospores.) Anelele I n s t i t u t u l u i
de C e r c e r a t i p e n t u P r o t e c t a P l a n t e l o r 1 0 : 6 3 - 7 0 .
( Re v. P l a n t P a t h o l (1 975) 5 4 : 6 1 0 )
Gough,
F . J . a n d 0. G. M e r k l e .
1 977.
The e f f e c t o f
s p e c k l e d l e a f b l o t c h on r o o t a n d s h o o t d e v e l o p m e n t
of wheat. Plan t Disease R eporter 61:597-599.
Narrower,
K.M. 1 9 7 8 .
S o me a s p e c t s o f t h e i n f e c t i o n
p r o c e s s and s p o r o g e n e s i s o f S e n t o r i a n o d o r u m and
S e B l o £.13, J L z i l l c l .
Page
20 i n :
Proc.
of
the
A ustralian
Septoria
Workshop.
Sept.
26-28.
Agricultural
Research i n s t i t u t e
N. S. W.
De p .
of
A g r i c u l t u r e . W ag g a-W ag g a.
N a r r o w e r , K . M. 1 9 7 8 . E f f e c t s o f m i x e d i n o c u l a o f
L e p t h o s n h a e r i a n o d o r u m a n d S e n t o r i a t r i t i c i on w h e a t
s e e d l i n g s . T r a n s . B r i t . M y c o l . Soc. 7 0 : 4 1 - 4 5 .
H e n d r i x , J . M. 1 9 6 7 . S t r i p e r u s t o f w h e a t . I n w W h e a t a n d
w h e a t i m p r o v e m e n t , e d . K. G. Q u i s e n b e r r y a n d L. P.
R e i t z . No 13 s e r i e s o f Ag r o n o my . A m e r i c a n S o c i e t y o f
A g r o n o my , pp 560.
Hess,
D and
G. S h a n e r I 9 8 3 . E f f e c t o f m o i s t p e r i o d
d u r a t i o n on s e p t o r i a t r i t i c i b l o t c h o f w h e a t .
P r o c e e d i n g s o f S e p t o r i a d i s e a s e W o r k s h o p . Bozeman
August 2 - 4 . (In p r e s s ) .
Hilu,
H. M. 1 95 6 . I n o c u l a t i o n ,
life
c y c le and h o s t p a r a s i t e r e l a t i o n s h i p o f S e p t o r i a t r i t i c i Ro b . o n
T r i t i c u m s p e c i e s . D is s . A b s t r . 16: 1550.
81
H o l m e s , S. J . I . a n d J . C o l h o u n . 1 9 7 4 . I n f e c t i o n o f w h e a t
by S e p t o r l a n o d o r u m a n d S e p t o r l a t r l t l o l i n r e l a t i o n
t o p l a n t a g e , a i r t e m p e r a t u r e and r e l a t i v e h u m i d i t y .
T r a n s . B r . My c o l . S o c . 6 3 : 3 2 9 - 3 3 8 .
H o lm e s , S . J . I. and J . C o lh o u n . 1 975. S t r a w b o rn e
inoculum of
h .o .d o ru m a n d
t r i t i c i in
r e l a t i o n t o i n c i d e n c e o f d i s e a s e on w h e a t p l a n t s .
PI. P a t h o l o g y 2 4 : 6 3 - 6 6 .
H y d e , P. M. 1 9 7 8 . A s t u d y o f t h e e f f e c t s o n
in o cu latio n
w ith
Leptojsphaeria nodo r u m. w ith r e s p e c t to
i n t e r a c t i o n s . P h y t o p a t h o l o g y . Z. 9 2 : 1 2 - 2 4 .
wheat
of
and
possible
H y d e , P . M. 19 8 1 . Th e e f f e c t s o n w h e a t o f i n o c u l a t i o n
w i t h P u c c i n i a s t r i i f o r m i s and S e n t o r i a nodorum w i t h
r e s p e c t t o p o s s i b l e i n t e r a c t i o n s . P h y t o p a t h o l o g y Z.
1 0 0 : 111- 1 2 0 .
James,
C. W. a n d C. S h i h. I 97 3 .
R e la tio n s h ip between
i n c i d e n s e and s e v e r i t y of Powdery m ildew and l e a f
r u s t on w i n t e r w h e a t . P h y t o p a t h o l o g y 6 3 : 1 8 3 - I 8 7 .
J e n k i n s , P. D.
a n d D. G. J o n e s 1 9 8 1 . The e f f e c t o f d u a l
i n o c u l a t i o n s of wheat c u l t i v a r s with Seotoria
t r i t i c i a n d S e o t o r i a n o d o r u m. P h y t o p a t h o l o g y . , Z .
101: 210- 2 2 1 .
J o h n s t o n , C. 0. 1 9 3 4 . T h e e f f e c t s o f m i l d e w i n f e c t i o n o n
the response
of wheat l e a f
tissues
norm ally
r e s i s t a n t to l e a f r u s t. Phytopathology 24:1045-1046.
Jones,
D. G. a n d P . D. J e n k i n s .
1978.
Predisposing
e f f e c t s
of
eyespot
( Za.S. u d £:£. e
S
h e r o o t r i c h o i d e s) on S e p t o r i a n o d o r u m i n f e c t i o n o f
w i n t e r w h e a t . Ann. a p p l . B i o l . 9 0 : 4 5 - 4 9 »
Jones,
J . B . a n d C. W. R o a n e .
1 9 7 9 . The e f f e c t o f
X a n t h o mo n a s t r a n s l u o s n s a n d S e D t o r i a n o do r u m on
w i n t e r w h e a t . P h y t o p a t h o l o g y 69 ( 5 ) : 5 3 5 .
Jones,
J . B . , C . W. R o a n e a n d D . D. W o l f . I 9 8 1 . T h e
effect
of
S e s to ria
s o io rs m . and
Xanthomonas
t r a n s l u c e n s f . s p . u n d u l o s a on p h o t o s y n t h e s i s a n d
t r a n s p i r a t i o n of wheat f l a g leaves.
Phytopathology
7 1 : 1 1 7 3 -1 177 .
82
Kh a n ,
M. A. 1 97 8.
Assessment tech n iq u es of S e p to ria
d i s e a s e s in wheat. Pages 38-40 in : Proc. of the
A u s t r a l i a n S e p t o r i a Workshop. Septem ber 26-28 .
A g ric u ltu ra l Research I n s t i t u t e .
N. S. W.
De p. o f
A g r i c u l t u r e W ag g a -W ag g a .
K i l p a t r i c k , R. A. , P. S. B a e z i n g e r a n d J . G. M o s e m a n .
1981.
Multiple inoculation technique for evaluating
resistance
of s i n g l e
barley see d lin g s to three
f u n g i . P l a n t D is e a s e 6 5 : 5 0 4 - 5 0 6 .
K u p r i y a n o v a , W. K. a n d T . P. Z h o k h o v a . 1 9 8 1 . E f f e c t o f
t e m p e r a t u r e on t h e d e v e l o p m e n t o f w h e a t r u s t .
Mikologiya i F i t o p a t o l o g i y a 15:236-238.
M a c D o n a l d , P. W. a n d G. A. S t r o b e l .
1970. Adenosine
d i p h o s p h a t e - g l u c o s e p y r o p h o s p h o r y l a s e and c o n t r o l of
s ta r c h accumulation in r u s t - i n f e c t e d wheat leaves.
PI. P h y s i o l o g y 4 6 : 1 2 6 - 3 5 .
Ma c k o , V . ,
E.J . Trione
and
S . A.
Young.
1 97 7 .
I d e n t i f i c a t i o n of the g e r m i n a t i o n s e l f i n h i b i t o r
from
uredospores
of
.
Phytopathology 67:1473-1474.
M a l c o l m , H. 1 9 7 8 .
A h o s t s p e c i f i c t o x i n e x t r a c t e d from
S e o t o r i a t r i t i c i . Pages 30-31 i n : Proc.
of the
A ustralian
Septoria
Workshop.
Sept.
26-28.
A gricultural
Research I n s t i t u t e
N. S. W.
De p . o f
A g r i c u l t u r e . Wa g g a - Wa g g a .
M a n n e r s , J . G. a n d D. G. G a n d y 1 9 5 4 . A s t u d y o f t h e
e f f e c t o f m i l d e w i n f e c t i o n on t h e r e a c t i o n o f w h e a t
varieties
to brown r u s t .
Annals of A ppl. Biol.
41 : 3 9 3 - 4 0 4 .
Mares,
D. J . a n d S. C o u s e n 1 9 7 7 - The i n t e r a c t i o n o f
y e l l o w r u s t CP u c c i n i a s t r i i f o r m i s l w i t h w i n t e r w h e a t
c u ltiv a rs
showing
adult
plant
re sista n c e :
m a c r o s c o p i c and m i c r o s c o p i c e v e n t s a s s o c i a t e d w i t h
the r e s i s t a n c e
reaction.
Physiological
Plant
Pathology 10:257-274.
M a r e s , D. J . 1 97 9. A l i g h t a n d e l e c t r o n m i c r o s c o p e s t u d y
of the
interaction
of y ello w
rust
(
s t r i i f o r mis) w ith a s u s c e p t i b l e wheat c u l t i v a r .
Annals of Botany 43:183-189.
/
U
83
Mendgen,
K. 1 9 8 1 .
Phytopathology.
N u trien t uptake
71:983-989.
in
rust
fungi.
M o r k , C o l l e e n C. 1 9 8 2 .
An e v a l u a t i o n o f f i e l d m e t h o d s o f
d is ea s e assesments in wheat fTritioum a e s tiv u m l for
s trip e rust (Puccinia s t r i i f o r m i s l .
M. Sc .
T h e s is
Oregon S t a t e U n i v e r s i t y .
M u r r a y , G. M. a n d R. H. M a r t i n .
1978.
Twenty nine
y e a r s o f S e p t o r i a a t Temora. P ag es 1 6 - 1 8 . i n : P r o s ,
o f t h e A u s t r a l i a n S e p t o r i a Wo r k s h o p . S e p t e m b e r 2 6 - 2 8
A g r i c u l t u r a l R e s e a r c h I n s t i t u t e . N. S. W. D e p . o f
A g r i c u l t u r e W ag g a -W ag g a .
P elletier,
G. J . , A. Co m e a u ,
and L. C o u tu r e . 1974.
I n t e r a c t i o n e n t r e I e v i r u s d e l a f e u i l l e r o u g e de
L.avoine
( BYDV) . &jg..£iSXA.& ajrfi-Il& e e t ZM -C fiA lii^
c o r o n a t a s u r Av e n a s a t i v a . P h y t o p r o t e c t i o n 5 5 : 9 - 1 2 .
P r e s t e s , A. M. 1 9 7 6 . S e p t o r l a t r i t i c i Ro b . Ex . D e s m . :
Host r e l a t i o n s h i p s , v a r i e t a l r e s p o n s e , and i n f l u e n c e
o n t h e d e v e l o p m e n t o f w h e a t r o o t s . P h . D. T h e s i s
Washington S ta te U n iv e rs ity .
Rufty
R e b e c a C. , T . T. H e b e r t a n d C. F. M u r p h y . 19 81 .
E v a lu a tio n of r e s i s t a n c e to S e p to ria nodorum in
wheat. P la nt Disease 65:406-409.
S a l i s b u r y , F. B. a n d C. W. B o s s . 1 9 7 8 . P l a n t
W a d s w o r t h P u b l i s h . Compa ny I n c . B e l m o n t
Physiology.
California.
S a n d e r s o n , F. R. 1 9 6 4 . E f f e c t o f l e a f s p o t ( S e p t o r i a
t r i t i c i ) i n a u t u m n - s o w n w h e a t c r o p s . New Z e a l a n d
Wh e a t R e v i e w . No 9 ( 4 ) : 5 6 - 5 9 .
S a n d e r s o n , F. R. 1 9 7 2 . A M y c o s p h a e r e l l a s p e c i e s a s t h e
a s c o g e n o u s s t a t e o f S e p t o r i a t r i t i c i . R o b . e x D e s m.
N.Z.J. B o t . I 0 : 7 0 7 - 7 0 9 .
S a n d e r s o n , F . R. 1 9 7 8 .
D ise a se l o s s a s s e s s m e n t of
S e p t o r i a t r i t i c i i n New Z e a l a n d . P a g e s 2 1 -1 t o 1 2 - 4
In:
Proc.
of the A u s t r a lia n Pathology Society.
W o r k s h o p A u g u s t 1977 L i n c o l n C o l l e g e .
S a n d e r s o n , F . R. a n d J . G. H a m p t o n . 1 97 8.
Role of the
p e r f e c t s t a t e s i n t h e e p i d e m i o l o g y o f t h e c o mmo n
S e p t o r i a d i s e a s e of w heat.
N. Z. J o u r n a l A g r i c.
R e s e a r c h 21 : 2 7 7 - 2 8 1 .
(
S c h a r e n . A. L . 1 9 6 6 .
C y c l i c p r o d u c t i o n of p y c n i d i a and
s p o r e s i n d e a d w h e a t t i s s u e by S e o t o r i a n o d o r u m.
Phytopathology 56:580-581.
S h a n e r , G. 1 9 7 6 . E p i d e m i o l o g y o f S e p t o r i a l e a f b l o t c h
c a u s e d by S e o t o r i a t r i t i c i . P a g e s 1 3 - 2 0 i n : P r o c.
S e p t o r i a D is e a s e s of w heat Workshop.
Oniv of
G e o r g i a , E x p e r i m e n t , GA. ; 4 - 6 May 1 9 7 6 . G e o r g i a
A g r i c . Exp. S t n . S p e c . P u b l . 4. 6 9pp.
S h a n e r , G. a n d R. E. F i n n e y . 1 9 8 2 . R e s i s t a n c e i n s o f t r e d
w inter
wheat
t o M iL G a a a iia m iiA H a a z a m i a i j & o l a .
Phytopathology 72:154-158.
Sharp,
E . L. a n d F . G. S m i t h . 1 9 5 2 . P r e s e r v a t i o n o f
PUccinia
uredospores
by
l y o p h y l i z a t i o n .
Phytopathology 42:263-264.
S h a r p , E. L . a n d E. R. H e h n . 1 9 6 3 . O v e r w i n t e r i n g o f
stripe
rust
in
w inter
wheat
in
Montana .
Phytopathology 53:1239-1240.
S h a r p , E . L. 1 9 6 5 . P r e p e n e t r a t i o n a n d p o s t p e n e t r a t i o n
e n v i r o n m e n t and d e ve l o p m e n t o f P u c c i n i a s t r i i f o r m i s
on w h e a t . P h y t o p a t h o l o g y 5 5 : 1 9 8 - 2 0 3 S h a r p , E . L . 1 967* A t m o s p h e r i c I o n s a n d g e r m i n a t i o n o f
u r e d o s p o r e s o f P u c c i n i a s t r i i f o r m i s . S c i e n c e 1 56 .No
37 8 0 , : 1 3 5 9 - 1 3 6 0 .
S h e a r e r , B. L . a n d J . C. Z a d o k s . 1 9 7 2 . The l a t e n t p e r i o d
o f S e n t o r i a n o d o r um i n w h e a t . I T h e e f f e c t o f
t e m p e r a t u r e and m o i s t u r e t r e a t m e n t s under c o n t r o l l e d
c o n d i t i o n s . N e t h e r l a n d s J o u r n a l of Pl ant Pathology
78:231-241 .
S h e a r e r , B. L . a n d L . D. J . S m i t h . 1 9 7 8 .
S tu d ie s in the
epidemiology of
ZAdfi-ZHE a n d S e z l f i Z i A
t r i t i c i in Western A u stra lia .
Pages 11-14. in :
P r o c . o f t h e A u s t r a l i a n S e p t o r i a Wo r k s h o p . S e p t e m b e r
26-28
. Agricultural
Research I n s t i t u t e .
N. S. W.
D e p t , o f A g r i c u l t u r e Wa g g a - Wa g g a .
S h i p t o n , W. A . , W. R. J . B o y d , A. A. R o s i e l l e a n d B.
Shearer.
1 9 7 1 . The c o m m o n s e p t o r i a d i s e a s e s
w h e a t . B o t . R e v . 37 : 23 I - 2 6 2.
L.
of
85
Sprague,
R. 1 9 5 0 . D i s e a s e s o f c e r e a l s
N o r t h Ameri ca. Ronal d p r e s s . 538pp.
and
grasses
in
S t r a l e y Mary L o u i s e .
1979.
Pathogenesis of Seotoria
!1j£>i Lo x uia ( B e r k ) B a r k , o n w h e a t c u l t i v a r s v a r y i n g i n
r e s i s t a n c e t o g l u m e b l o t c h . Pb . D. T h e s i s . M o n t a n a
State University.
S t r o b e l , G. A. a n d E., L . S h a r p 1 9 6 5 .
Proteins
associated
with
infection
type
of
s t r i i f o r m i s . Phytopathology 55:413-414.
of wheat
S t u b b s , R. W. 1 9 6 7 - I n f l u e n c e o f l i g h t i n t e n s i t y o n t h e
r e a c t i o n s o f w h e a t s and b a r l e y s e e d l i n g s t o P u c c i n i a
s t r i i f o r m i s . Phytopathology 57:615-617.
T i n l i n e , R. D. 1977- M u l t i p l e i n f e c t i o n s o f t h e s u b c r d w n
i n t e r n o d e o f w h e a t ( T r i t i c um a e s t i v u ml by c o mmo n
r o o t r o t f u n g i . Can. J o r . B o t . 5 5 : 3 0 - 3 4 .
T o l l e n a a r , H. a n d B. R. H o u s t o n . 1 9 6 5 . E f f e c t o f s p o r e
d e n s i t y on i n v i t r o g e r m i n a t i o n o f u r e d o s p o r e s o f
P u c c i n i a s t r i i f o r m i s . Phy top at h o lo gy 55:1080.
T o l l e n a a r , H. a n d B . R. H o u s t o n . 1 9 6 7 . A s t u d y o f t h e
e p id e m io lo g y of s t r i p e r u s t , P u c c in ia s t r i i f o r mis
W e s t , i n C a l i f o r n i a . Can. J . B o t . 4 5 : 2 9 1 - 3 0 7 .
Va n
d e r W a l , A. F . , B. L. S h e a r e r a n d J . C. Z a d o k s .
1970. I n t e r a c t i o n b e t w e e n P u c c i n i a r e c o n d i t e f . sp.
t r i t i c i n a a n d S e p t o r i a n o d o r u m on w h e a t a n d i t s
e f f e c t s o n y i e l d . N e t h . J . P l a n t P a t h o l . 76 : 2 6 1 263 -
Van
der
Wa l ,
A.
F . and
M. C. C o w a n .
1 9 7 4 . An
e c o p h y s i o l o g i c a l aproach to crop l o s s e s e x e m p l if ie d
i n t h e s y s t e m w h e a t , l e a f r u s t and gl ume b l o t c h . I I
De vel opment , g r o wt h and t r a n s p i r a t i o n i n u n i n f e c t e d
p l a n t s and p l a n t s i n f e c t e d w i t h P u c c i n i a r e c o n d i t e
f . sp. t r i t i c i n a and / or S e p t o r i a
in a
clim ate
chamber
experim ent.
Neth.
J.
Plant.
P a t h o l . 8 0 : 192-214.
V o l i n , R. B. 1 9 7 1 .
P h y s i o l o g i c a l r a c e d e t e r m i n a t i o n and
e n v i r o n m e n t a l f a c t o r s a f f e c t i n g the d e ve lo p m e nt of
i n f e c t i o n type in s t r i p e r u s t ( Puccinia s t r i i f o r m i s
W e s t . ) Pb. D. T h e s i s M o n t a n a S t a t e U n i v e r s i t y .
86
W e b e r , G. E. 1 9 2 2 . S e p t o r i a d i s e a s e s o f c e r e a l s .
S e p t o r i a d i s e a s e s of wheat. Phytopathology
585 .
P a r t 2.
12:537-
W i l l i a m s , J . R. a n d D. G. J o n e s . 1 9 7 3 - a . E p i d e m i o l o g y o f
S e n t o r i a t r i t i c i and S e p t o r i a nodorum. VII. e f f e c t s
of
the
previous
years
infection
on
disease
d e v e l o p m e n t a nd y i e l d i n s p r i n g w h e a t s . T r a n s . Br.
My c o l . S o c . 6 1 : 3 3 - 3 9.
W i l l i a m s , J . R. a n d D. G. J o n e s . 1 9 7 3 - b . I n f e c t i o n o f
g r a s s e s by S e o t o r I a n o d o r u m a n d S e o t o r l a t r i t i c i .
T r a n s . Br. M y c o l . S o c . 6 0 : 3 5 5 - 3 5 8 .
Yarwood,
C. E . 1 9 5 9 .
Predisposition.
In
:"Plant
P a t h o l o g y : a n a d v a n c e d t r e a t i s e " e d . J . G. H o r s f a l l
a n d A. E . D i m o n d . New Y o r k A c a d e m i c p r e s s . 1 : 5 2 1 562.
Z a d o k s , J . C. 1 9 6 1 . Y e l l o w r u s t o n w h e a t . S t u d i e s i n
epidem iology
and p h y s i o l o g i c
specialization.
T i j d s c h r . P l Z i e k t . ( N e t h . J . P I . P a t h . ) 67 : 6 9 - 2 5 6 .
Z a d o k s , J . C. a n d R. D. S c h e i n 1 9 7 9 . E p i d e m i o l o g y a n d
P l a n t D i s e a s e M a n a g m e n t . New Y o r k , O x f o r d . O x f o r d
U n i v e r s i t y P r e s s pp.427.
APPENDIX
Table 20.
Treatment
Code
Increase
in
leaf
weight
expressed
as
p e r c e n t a g e o f t h e c o n t r o l ( 0 0 0 0 ) i n d u c e d by
t h e p a t h o g e n s H z s .f i.s .r is s .r s .l.ls g r a m i n i c o l a ( S )
a n d P u c c i n i a s t r i i f o r mi s (R) i n f o u r s p r i n g
w heatcultivars.
Lakhish
Anza
C ultivar
Lemhi
Baart
I/
00
SO
00
SO
OS
SO
OS
Mean
00
00
RO
OR
RO
RO
OR
0
8
68 s
14
22.
27
3
20
0
6
3
4
I
10
8
0
-4
64
22
84
40
37
5
35
O
O
O
S
0
2
86
11
112
34
32
G
a
G
6
39
indicate
code
d ig its
of
the
f i r s t
two
I /
The
M vcosohaerella
gram inicola
inoculated
on
time
one o r
t i m e two ( S p r e s e n t ,
0 absent).
The
third
and f o u r t h
indicate
P u c c i n i a s t r i i f o r m i s i n o c u l a t e d on t i m e one and
t i m e two ( R p r e s e n t , 0 a b s e n t ) .
o S i g n i f i c a n t l y d i f f e r e n t from the c o n tr o l as d e term in e d
by LSD ( P< 0 . 0 5 ) .
88
Table 21.
Number
A n a l y s i s o f v a r i a n c e and o r t h o g o n a l c o m p a riso n s
of percent g e rm in a tio n of Puccinia s t r i i f o r m i s
u r e d o s p o r e s t e s t e d on p o l y e t h y l e n e m e m b r a n e s .
Treatment
Mean
%
of g e rm in a tio n
n =9
U r e d o s p o r e s a l o n e . (R)
Uredospores in presence of
bud-spores of M ycosphaerella
K ram inicola.
( HS)
U redospores in presence of
l i q u i d m e d i a .( Yeast e x tr a c t+
sucrose)
(RM)
I
2
3
d.f.
2
24
R
Contrast
SE. c o n t r a s t
Sum S q u a r e s
T (24)
P- V a l u e
o
Significant
5 .0
15.8
of v a ria n c e
Analysis
Source of v a r .
Treatment
Residual
18.4
M. S .
456.0
164 .5
OrthoKonal
RS
vs
F
2.77
P
0.08
contrast
R
the 0.05
RM
2.68
6 .04
32 . 00
0.44
0 . 66
- 1 3 - 44
6 .05
813.40
-2.22 ®
0.04
at
vs
level
of
probability.
Interactions of Puccinia striiformis and
3 1762 00185607 7
N378
M262
cop.2
Madariaga, R. B.
Interactions of
Puccinia Striiformis and
Mycosphaerella
Graminicola on wheat
Al 2 6 2 .
Cop. 2