November 19?3
PNW-208 EF FECT OF MONTH OF GRAFTING ON DOUGLAS-FIR GRAFT COMPATIBILITY by
Donald L.
Copes, Principal Plant Geneticist
c:/3 . ,3-:::Jc?, 5
COPY
OLYMPIA LAB
ABSTRAC'l'
When the comparison unions were grafted on
the same date no irregularities in graft compati­
bility between unions with identical stock-scion
combinations were detected but inconsistent com­
patibility tests often occurred when the comparison
Some
unions were grafted in different months.
stock-scion combinations were compatible when
grafted early in the growing seasonJ whereas
the same combinations were incompatible when
In orchardsJ it
grafted later that same year.
is important that compatibility test grafts and
production grafts be grafted on the same date or
a less than perfect correlation will exist between
Within
the compatibility of the same two unions.
the same year J the month of grafting had little
effect on the average compatibility of each clone.
Keywords: Grafting, Douglas-fir, Pseudotsuga
menziesii.
INTRODUCTION
True graft compatibility is
determined primarily by the inherent
likeness of stock and scion.
Since
most incompatibility reactions are
growth processes, they are subject
to environmental modification.
Argles (1937) realized this and
stated that graft incompatibility
was an inherent antagonism or dis­
cordant association somewhat subject
to the influence of environment and
treatment.
Influence of treatment
and environment on compatibility
have been demonstrated in a number
of studies where compatible stock­
scion combinations became incompati­
ble due to changes in climate
(Ching 1938), bud mutation (Posnette
and Cropley 1959), male flowers
(Jimenez 1957), fruit formation
(Gravel 1954), age (Herrero and
Tabuenca 1969), soils (Carlson
1965), seasonal metabolism (Herrero
1951), and double-grafting (Herrero
and Tabuenca 1962).
Incompatibility symptoms in
Douglas-fir grafts (Pseudotsuga
menziesii (Mirb.) Franco) (Copes
1970a) are similar to those reported
for grafts of horticultural plants
which were subject to modification
by changes in treatment or environ-­
ment.
Temperature at the graft
union had a direct influence on
how long incompatible Douglas-fir
grafts survived.
Graft unions
°
grown at 50 F. died at a younger
age than did grafts with unions
°
°
grown at 70 or 90 F. (Copes 1967b).
In another study, compatibility of
identical stock-scion combinations
was altered by double-grafting
(Copes 1971).
In this case, incom­
patibility was induced at the union
joining the scion and interstock.
In addition, numerous inconsisten­
2
cies in compatibility test results
occurred in a Douglas-fir seed
orchard where compatibility test
grafts were not made until 3 to
10 years after the production
grafts.
Anatomical examination
of some test graft unions indi­
cated compatible stock-scion com­
binations, whereas the surviving
production grafts of the same
scion-stock combination had defi­
nite external symptoms of incom­
patibility (scion overgrqwth and
bark necrosis) (unpublished seed
It is thought that
orchard data).
lack of correlation between test
and production grafts resulted
from age-induced changes in the
biochemical or physiological
constitution of the stock and
scion.
The following study explored
the hypothesis that the graft
compatibility could be altered by
grafting at different times during
the growing season.
Compatibility
was determined for grafts which
had been grafted on the same stocks
during the first week of each month
The main
from April to September.
variables influenced by this treat­
ment were the physiological con­
dition or stage of growth of the
stocks at the time of grafting,
and the length of the growing
season following grafting.
METHODS
Field grafting of the main
study was done near Corvallis,
Oregon, in 1968 and 1969 with
Douglas-fir clones 9, 16, 24, and
26 from the Soleduck block of the
Dennie Ahl Seed Orchard near Shelton,
Washington.
One graft of each clone
was cleft-grafted each month on
lateral branch tips of 25 stocks.
Grafting was done during the first
week of each month from April to
September.
One experienced grafter
did all the grafting and used uni­
form grafting techniques throughout
the study.
Scion collection,
storage conditions, and initial
graft survival have been described
in a previous report (Copes 1970b).
stocks.
The unions were sacrificed
in September 1972 and prepared for
anatomical study using the tech­
niques previously described.
RESULTS AND DISCUSSION
Grafts made in 1968 and 1969
were sacrificed for anatomical
study in September 1970 and 1972,
respectively.
Sacrificed unions
were fixed in 50 percent alcohol,
microtomed into transverse sections,
stained with safranin 0 and fast
green and examined under a micro­
scope for the presence of wound­
xylem areas (Copes 1967a).
Grafts
were recorded as incompatible when
they contained wound-xylem areas
and compatible when free of wound­
xylem areas.
In the supporting study, no inconsistency between unions with identical stock-scion combinations was found when all were grafted on the same day.
All grafts of one clone on one stock were either compatible or incompatible.
But inconsistency within identical stock-scion combinations of the primary study often occurred when unions were compared that had been grafted in different months.
For example, scion clone 9 and stock No. 1 formed compatible unions when grafted together in April and May, but developed incompatible unions when grafted together in June, July, and August.
This inconsistency was the primary cause of monthly within-clone variation (table 1).
Some clonal variation was evident in this erratic behavior.
Clones 9 and 16 exhibited more inconsistency Clones than did clones 24 and 26.
9 and 16 were inconsistent with 16 to 52 percent of the stocks, whereas only 4 to 8 percent of the stock-scion combinations with clones 24 and 26 showed similar behavior. In supporting grafting study,
variation was checked between
unions with identical stock-scion
combinations when all unions on
each stock were grafted on the
same date.
Fifty 10-year-cld
stocks were each grafted on April 5
and 6, 1971, with five grafts of
one scion clone.
A different scion
clone was used on each of the 50
Inconsistency in compatibility
tests is of great concern to seed
orchard managers because it points
out the necessity for production
and test grafts to be grafted at
the same date.
If either graft
fails to survive, no attempt should
be made to regraft it later that
same year.
If it is felt necessary
to utilize the one surviving graft,
A different group of 25 stocks
was used each year.
Stocks grafted
in 1968,were local trees that had
naturally regenerated the area 9 to
12 years before with seed from
adjacent 30-year-old trees.
The
stocks grafted in 1969 were all
12-year-old planted trees which
came from four different western
Oregon seed sources.
All stocks
were located within 300 meters of
each other on nearly identical
sites.
3
-�---
Table I.--Compatibility of clones 9
16
and 26 when grafted on 25 stocks
24
each month {April to September) in 1968 and 1969
Scion clone number
Month
9
grafted
1968
1
16
1969
1968
1
Averages
24
1969
1968
1
26
1969
1968
1
1969
1968
1969
- - - - - - - - - - - - - - - - - - Percent1/
- - - - - - - - -
-
-
1968 +
1969
- - - - - -
A pril 1
65
63
95
70
91
44
84
79
84
64
74
May
59
77
68
89
86
45
86
76
75
72
73
June
40
76
83
82
33
81
79
72
67
70
July
93
75
73
August
87
Se ptember
83
87
87 71 --
Percent
compatibi1i ty
55
70
74
80
87
45
88
number compatible grafts
1/ p
x lOO
ercent equa1s the
n
·
sample size was less than 10.
•
78
77
70
75
Percentage values are not given where
regrafting should be delayed until
several closely related seed trees.
the following year and should only
Data from clone 24 in 1968 suggest
be done on the same date that the
surviving graft was grafted the
that this hypothesis may be true.
preceding year.
Regrafting 2 to 10
years after the first graft is even
greater chance of discord or incon­
seed orchard on random, unrelated
stocks.
The 45-percent compati­
bility obtained in this study in
sistency between compatibility of
1969 on stocks grown from four
production and test grafts is likely
different seed sources was similar
more undesirable because an even
(I
Clone 24 was highly incompatible
when grafted in the Washington
to occur.
The safest method to use
to clone 24's orchard performance.
is to rogue the surviving graft
But the 91-percent value obtained
from the preceding year and make
in 1968 is far higher than the
two new grafts.
expected value.
This could have
resulted from clone 24's having
The month of grafting appeared
to have little influence on average
compatibility.
One exception to
many compatibility factors in
common with the 1968 stocks
(Copes 19 73).
this statement might be August.
August grafts averaged 87-percent
compatibility (table 1), consider­
The comparison between grafts
made in the same month, but in
ably higher than the study average
different years, indicated a differ­
of 75 percent.
ence in average compatibility be­
The August data may
simply be small sample variation or
tween April 1968 and 1969 grafts
may indicate that an actual increase
(84- vs.
in stock-scion compatibility oc­
curred in August.
If the former
(table 1).
64-percent compatibility)
This difference was
not thought to have resulted from
is true, no practical use of the
different stock populations having
increase in compatibility is fore­
seen because only 19 to 35 percent
been used each year; between-year
comparisons for the other months
graft take is obtained by field
showed similar results in both
grafting during this hot, dry month
years (table 1).
(Copes 1970b).
No reasonable sta­
tistical test of these data can be
It appears that the physio­
logical likeness of the stock and
made.
scion during the first several
Comparison of 1968 and 1969
months following grafting may
grafting results did not reveal a
determine compatibility.
uniform trend for all four clones
mental or treatment changes which
(table 1).
occur later have a much smaller
Clones 24 and 26 had
Environ­
higher average compatibility in
effect on the compatibility status
1968,
of adjacent stock and scion cells.
whereas clones 9 and 16 had
higher average compatibility in
1969.
Part of this clonal varia­
It is not possible to deter­
tion can be attributed to the use
mine which environmental variables
The
of different stocks each year.
1968 stocks were from natural seed­
caused the observed inconsistencies.
The stocks and scions passed through
ing which may have come primarily
many different growth phases in
from one adjacent seed tree or from
the months following grafting.
5
For example, April grafts were made
when the stock's vegetative buds
were expanding.
May grafts were
made shortly after the stocks had
burst their vegetative buds.
June
grafts were made when the stocks
were actively elongating their vege­
tative shoots.
July grafts were
made as shoot elongation neared
completion and as the transition
from springwood to summerwood oc­
curred.
August and September grafts
were made after shoot elongation
was completed but while the cambium
was still active.
Correlated with
these growth changes was first the
lengthening and then the shorten­
ing of growing season as the year
progressed.
This had a direct
effect on the amount of tissues
which formed across the graft union
before cambial activity ceased or
Other envi­
slowed for the winter.
ronmental variables such as tempera­
ture, photoperiod, and rainfall
also underwent seasonal changes
during the study.
Physiological
changes also may have occurred in
the scions while they were being
held in cold storage before being
grafted.
What changes were induced
in the stock and scion by these
variables are not known, but it is
evident that changes occurred which
caused some compatible stock-scion
combinations to become incompatible
and some incompatible combinations
to become compatible.
LITERATURE CITED
Argles, G. K.
1937. A review of the literature on stock-scion incompatibility in
fruit trees, with particular reference to pome and stone
fruits.
Imp. Bur. Fruit Prod. Tech. Commun. No. 9, 115 p.
East Malling Res. Stn.
Carlson, R. F.
Growth and incompatibility factors associated with apricot
1965.
Report I. Mich. Agric. Exp.
scion/rootstock in Michigan.
Stn. Q. Bull. 48: 23-29.
Ching, W. T.
1938.
Studies in incompatibility between stock and scion, with
special reference to certain deciduous fruit trees.
J.
Pomol. & Hortic. Sci. 15: 267-325.
Copes, D. L.
1967a.
A simple method for detecting incompatibility in 2-year-old
grafts of Douglas-fir.
USDA For. Serv. Res. Note PNW-70,
8 p. , illus.
Pac. Northwest For. & Range Exp. Stn. , Portland,
Oreg.
Copes, Donald
Initiation and development of graft incompatibility symptoms
1970a.
in Dougias-fir.
Silvae Genet. 19 (2-3): 101-107, illus.
6
Copes, Donald L.
1970b. Effect of date of grafting on survival in Douglas-fir.
USDA For. Serv. Res. Note PN\>J-135, 4 p. Pac. Northwest For.
& Range Exp. Stn., Portland, Oreg.
1971.
Interstock trials with grafted coastal Douglas-fir. USDA
For. Serv. Res. Note PNW-151, 6 p. Pac. Northwest For. &
Range Exp. Stn,, Portland, Oreg.
1973.
Inheritance of graft compatibility in Douglas-fir. Bot. Gaz. 134(1): 49-52. Copes, Donald Louis
1967b. Graft incompatibility and union formation in Douglas-fir
(Pseudotsuga menziesii [Mirb.] Franco). 186 p. Ph.D. thesis,
Univ. Idaho, Moscow.
Gravel, L.
1954.
Enquete sur le compartment du noyer d' amerique en tant que
port-greffe de varietes de noyers indigenes. Rev. For. Fr.
No. 4: 217-224.
Herrero, J.
1951. Studies of compatible and incompatible graft combinations
with special reference to hardy fruit trees. J. Hortic. Sci.
26: 186-237.
1962.
---:--,--:--
1969.
and M. C. Tabuenca
Incompatilidad entre patron e injerto. VI. Observaciones
en uniones de peral sombre membrillero.
[Incompatibility
between stock and scion. V I. Observations on unions of
pear and quince.]
An. Estac. Exp. Aula Dei 7: 64-78.
(Hortic. Abstr. 34: 329.)
and M. C. Tabuenca
Comportamiento
Incompatilidad entre e patron e injerto. X.
de la combination melocotonero mirobolan injerado en estado
cotiledonar.
[Incompatibility between rootstock and scion.
X.
Behavior of the combination peach/myrobolan grafted at
the cotyledonary stage.]
An. Estac. Exp. Aula Dei 10:
93 7-945. (Hortic. Abs tr. 41: 5898.)
Jimenez, H.
1957. Injertos entre espacies de carica.
Agron. Trop. Venez. 7: 33-37.
Posnette, A. F., and R. Cropley
1959. A selection of Williams' Bon Cretien pear compatible with quince
rootstocks. Annu. Rep. East Malling Res. Stn. 1958, A42: 91-92.
7
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