AGRICULTURAL UNIVERSITY OF ATHENS
HOST-PARASITE INTERACTION
REVEALS INTER- AND
INTRASPECIFIC VARIATION FOR
PHELIPANCHE SPECIES
Lyra1, D., Economou1, G. and Kotoula-Syka2, E.
1. Agricultural University of Athens Hellas
2. Democritus University of Thrace Orestiada Hellas
E-mail: dionyssialyra@yahoo.com
2nd International Conference on «Novel and Sustainable Weed Management in arid and semi-arid agro-ecosystems» 7-10 September Santorini Hellas
Introduction
Material & Methods
Results
Discussion & Conclusions
O. cumana
Ph. aegyptiaca
O. crenata
O. minor
(Gianniantonio Domina 2005)
Ph. ramosa
Introduction
Material & Methods
Results
Broomrapes as holoparasites
depend on their host-plants for
resources
in order to secure their survival and
perpetuation
Discussion & Conclusions
Introduction
O. cumana
Ph. aegyptiaca
Results
Material & Methods
Discussion & Conclusions
O. crenata
Orobanche and Phelipanche
species
A varying degree of
host-plant specificity
Ph. ramosa
O. minor
Introduction
Material & Methods
Results
Discussion & Conclusions
Introduction
Material & Methods
Results
Hosts
Broomrapes
HOST
Root
system
H3C
CH3
O
SPECIFICITY
O
H3C
CH3
O
O
H
O
OH
H3C
CH3
O
O
H
O
O
O
O
CH3
H
OH
O
Discussion & Conclusions
O
O
O
CH3
CH3
5-Deoxystrigol
Orobanchol
2‘-epi-Orobanchol
Seeds
Introduction
Material & Methods
Results
Discussion & Conclusions
During host-parasite interaction,
A
VARIATION
has been observed from both sides which has to do with………
Introduction
Material & Methods
Results
Discussion & Conclusions
1st case
Hosts
Solanaceae
Cannabidaceae
Compositae
Cruciferae
Cucurbitaceae
…stimulants
HOST
SPECIFICITY
Broomrape
species
Introduction
Host
Results
Material & Methods
Discussion & Conclusions
2nd case
Broomrape
populations
… variable
response
HOST
SPECIFICITY
Pop. 1
Pop. 3
Pop. 2
Pop. 4
Introduction
Results
Material & Methods
Discussion & Conclusions
Hosts
Not all host plants do
they exude substances
with the same chemical
composition
Broomrapes
HOST
SPECIFICITY
Broomrape seeds
demonstrate different
sensitivity in the
biochemical stimulus
derived from planthost roots
The main
research objective
of our study
Introduction
Material & Methods
Results
Discussion & Conclusions
Why are we interested in studying population diversity?
Populations are categorized according to the level of
divergence between them
Variability (morphological, genetical, physiological, spatial
heterogeneity)
Hybrids / Subspecies (Ph. ramosa / Ph. aegyptiaca)
Races (O. cumana)
Host-specificity is one of the driver of genetic divergence
Impact on decision-making processes for Orobanche control
Introduction
Material & Methods
Results
Discussion & Conclusions
Broomrape plants were collected from
naturally parasitized tobacco and
tomato crops
Introduction
Material & Methods
Results
Discussion & Conclusions
Ph. aegyptiaca
Ph. ramosa / Ph. aegyptiaca
Ph. ramosa
Introduction
Material & Methods
Results
Discussion & Conclusions
Ph. ramosa
Introduction
Material & Methods
20 Phelipanche ramosa populations
Results
Discussion & Conclusions
28 Phelipanche aegyptiaca populations
Introduction
Material & Methods
Results
Discussion & Conclusions
1st experiment
• Hosts: 2 rapeseed varieties (EXACT, CALIFORNIA) - tobacco
3 Phelipanche ramosa populations
4 Phelipanche aegyptiaca populations
2nd experiment
•Host: tobacco
13 Phelipanche ramosa populations
6 Phelipanche aegyptiaca populations
3rd experiment
•Host: tomato
18 Phelipanche ramosa populations
9 Phelipanche aegyptiaca populations
Introduction
Material & Methods
Results
Discussion & Conclusions
MEASUREMENTS
• Germinated seeds
• Formed tubercles
Plastic bag assays were used to
study hosts and holoparasite
interactions in vivo
Introduction
Results
Material & Methods
Discussion & Conclusions
Statistical analysis
* Data did not follow Normal Distribution
* Kruskal – Wallis test / Nemenyi test
?
* Box-Whisker plot
Median
AEG
Data range
Outliers
RAM
0
4
Mean
Interquartile
range
8
12
16
20
24
Introduction
Material & Methods
st
1
Results
Discussion & Conclusions
experiment
C a n o l a – To b a c c o
Interspecific variability
Germination (%)
100
Formed tubercles
b
80
5
60
4
b
3
40
a
20
2
a
1
0
CALIFORNIA EXACT TOBACCO
100
a
0
CALIFORNIA
EXACT
24
c
b
TOBACCO
b
20
80
60
a
a
16
b
12
40
8
20
a
4
0
CALIFORNIA EXACT TOBACCO
0
CALIFORNIA
EXACT
TOBACCO
Intraspecific variability
Germination (%)
(Phelipanche populations collected on tobacco same region-same year)
100
e
O. ramosa
100
100
O. ramosa
O. aegyptiaca
O. ramosa
80
80
80
d
d
d
60
60
60
c
40
40
c
20
a
b
a
c
20
LA1
LA2
LA3
LA4
LA5
LA6
b
a
LA2
Broomrape populatIons
8
O. ramosa
c
b
4
ab
ab
a
O. aegyptiaca
LA3
LA4
LA5
LA6
LA7
0
LA1
15
O. ramosa
O. aegyptiaca
LA2
LA3
LA4
LA5
LA6
LA7
Broomrape populatIons
e
36
O. ramosa
O. aegyptiaca
30
12
6
bc
c
Broomrape populatIons
O. aegyptiaca
d
20
a
LA1
LA7
O. aegyptiaca
40
0
0
Formed tubercles
f
e
9
b
6
d
24
d
18
c
12
2
3
a
a
a
LA1
LA2
0
LA3
LA4
a
a
LA5
LA6
Broomrape populatIons
CALIFORNIA
0
LA7
6
a
a
a
LA1
LA2
LA3
c
bc
a
LA4
LA5
LA6
Broomrape populatIons
EXACT
LA7
ab
a
a
LA4
LA5
0
LA1
LA2
LA3
LA6
Broomrape populatIons
TOBACCO
LA7
results
•
•
•
•
•
•
Ph. ramosa‘s seeds germinated more by tobacco
More host-specific
Ph. aegyptiaca’s seeds germinated more by canola
Less host-specific
Less tubercles on canola root system
More tubercles on tobacco root system
Introduction
Material & Methods
nd
2
Results
Discussion & Conclusions
experiment
Tobacco
Interspecific
Variability
?
a
AEG
Ph. aegyptiaca
b
Ph. ramosa
RAM
0
20
40
60
80
100
6
9
12
15
Germination (%)
?
a
AEG
Ph. aegyptiaca
a
RAM
Ph. ramosa
0
3
Formed tubercles
Germination (%)
100
O. aegyptiaca
O. ramosa
Region 2
2004
80
60
Region 2
2004
Region 1
Collection year 2002
Region 1
2003
Intraspecific
variability
40
20
0
? A1A2A3A4A5RARBRCRDRERFRGRHRI RJRKRLRM
Formed tubercles
15
O. ramosa
O. aegyptiaca
Region 2
2004
12
Region 2
2004
9
Region 1
Collection year 2002
Region 1
2003
6
3
0
?1
A1
A2
A3
A4
Phelipanche populations
A5
RA
RB
RC
RD
RE
RF
RG
RH
RI
RJ
RK
RL
RM
Ph. ramosa
populations
collected on
tobacco
different regionsdifferent years
results
•
•
•
•
Ph. ramosa‘s seeds germinated more compared to
Ph. aegyptiaca’s seeds
The number of tubercles was not statistical
different for both species
High variability among and within regions
High variability among and within collective years
Introduction
Material & Methods
rd
3
Results
Discussion & Conclusions
experiment
Tomato
Interspecific
Variability
?
a
Ph. aegyptiaca
AEG
b
Ph. ramosa
RAM
0
20
40
60
Germination (%)
80
100
?
a
Ph. aegyptiaca
AEG
b
RAM
Ph. ramosa
0
4
8
12
Formed tubercles
16
20
24
Germination (%)
100
Region 2
2004
Region 3
2003
Region 4
2004
80
60
Intraspecific
variability
Region 3
Collection year 2002
40
20
0
24
Formed tubercles
Region 1
2004
20
16
O. aegyptiaca
O. ramosa
? ?1 ?2 ?3 A
4 1O.
A2aegyptiaca
A3A4A5A6A7A8AR
9A
RB
RC
RD
RERF
RG
RHRI
RR
JK
RL
RM
RN
RORP
RQ
RR
O. ramosa
Region 1
2004
Region 2
2004
Region 3
2003
Region 3
Collection year 2002
Region 4
2004
12
8
4
0
? ?1 ?2 ?3 A1
4 A2A3A4
A5APhelipanche
6A7A8
AR
9A
RB
RC
RD
RE
RF
RG
RHRIRR
JK
RL
RM
RN
RO
RP
RQ
RR
populations
Ph. ramosa
populations
collected on
tobacco
different regionsdifferent years
results
•
•
Ph. ramosa‘s seeds germinated more compared to
Ph. aegyptiaca’s seeds
The number of tubercles was statistical different
for both species
•
High variability among and within regions
High variability among and within collective years
•
Ph. ramosa seems to be more host-specific
•
Introduction
Results
Material & Methods
Discussion & Conclusions
Why were not many tubercles formed on canola root system by
Ph. ramosa (1st experiment)?
Tobacco – a traditional crop
Canola – a newly introduced cultivation
•
•
Why were not many tubercles formed on tobacco root system
by Ph. ramosa, although germination was high (1st experiment)?
Tobacco variety
Second level of resistance
•
•
Are Ph. aegyptiaca/Ph. ramosa highly host-specified species ?
No
Introduction
Material & Methods
Results
Discussion & Conclusions
Where can population variability be attributed?
Massive collections of seeds
Weight
Shape
Size
Seed coat
Genetic
material
Physiological age
Dormancy
Introduction
Material & Methods
Results
Discussion & Conclusions
Spatial heterogeneity
Climate
Landscape
Topography
Soil