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Potential of the entomopathogenic fungus
Beauveria bassiana as an endophyte in
grapevine Vitis vinifera
Prof. Dr. M.-H. Poehling
Prof. Dr. A. Reineke
Yvonne Rondot and Annette Reineke
Hochschule GEISENHEIM University
Institute of Phytomedicine
IOBC-WRPS meeting "Integrated Protection
and Production in Viticulture"
Ascona,16th Oct. 2013
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• entomopathogenic fungus
• worldwide distribution, naturally occurring
in soil
• wide host range
• is able to colonize plants endophytically
• commercial products:
• Naturalis® (contains strain ATCC 74040)
• BotaniGard® 22WP (contains strain GHA)
• strains are registered on Annex 2,
Regulation (EC) No. 1107/2009
Beauveria bassiana
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Tritrophic interaction
pathogens e.g. Planococcus ficus, Otiorhynchus sulcatus,
Plasmopara viticola
plant Vitis vinifera
endophyte Beauveria bassiana
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Influence on insect pests
Endophytic establishment of B. bassiana
Potential against plant pathogens
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Influence on insect pests
• Is any effect of endophytic B. bassiana on mortality and growth of pest insects evident?
• Are the insects influenced by endophytic B. bassiana in their host choice behavior?
Endophytic establishment of B. bassiana
• Is it possible to establish B. bassiana as an endophyte within Vitis vinifera plants?
• Is any effect of endophytic B. bassiana on plant growth of the plants evident?
Influence on plant pathogens
• Is any effect of endophytic B. bassiana on the disease severity of Plasmopara viticola evident?
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Inoculation
Treatments:
• different strains (ATCC 74040 and GHA)
• different conidia concentrations
• conidia suspension vs. product Naturalis®
• inoculation conditions: wrapping the plants in plastic bags for 24 h after inoculation
all treatments were inoculated with handheld-sprayer on the upper and lower leaf surface
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Re-isolation of B. bassiana
surface sterilization
placing on BSM
visual assessment
incubation (24 C, dark)
leaf discs
2 min in 0.5 % NaOCl, 2 min in 70 % ETOH,
rinsed with sterile dest. water
0
2 5 0 0 0
5 0 0 0 0
7 5 0 0 0
1 0 0 0 0 0
1 2 5 0 0 0
1 5 0 0 0 0
1 7 5 0 0 0
7 5 1 0 0 1 2 5 1 5 0 1 7 5 2 0 0 2 2 5 2 5 0
B a 0 1 _ B a _ 1 2 _ B a 1 3 _ A 6 .F 0 1 _ 1 2 0 8 2 3 1 1 8 D
S ize (nt)
Dye S
ignal
molecular detection
optaining 6 leaf discs with a cork borer
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Endophytic establishment of B. bassiana
• Is it possible to establish B. bassiana as an endophyte within Vitis vinifera plants?
• Is any effect of endophytic B. bassiana on plant growth of the plants evident?
• endophytic colonization of grapevine leaves by B. bassiana is
possible
• presence of B. bassiana in grapevine plants was confirmed up to
28 days after inoculation
• different treatments had no significant effect on the colonization
rates
• endophytic B. bassiana had no negative effect on growth of
potted grapevine plants
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Influence on insect pests
• Is any effect of endophytic B. bassiana on mortality and growth of pest insects evident?
• Are the insects influenced by endophytic B. bassiana in their host choice behavior?
Endophytic establishment of B. bassiana
• Is it possible to establish B. bassiana as an endophyte within Vitis vinifera plants?
• Is any effect of endophytic B. bassiana on plant growth of the plants evident?
Influence on plant pathogens
• Is any effect of endophytic B. bassiana on the disease severity of Plasmopara viticola evident?
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Vine mealybug Planococcus ficus
Symptoms/Damage
• phloem feeding causes vine weakening,
defoliation
• honeydew excretion covers berries and
leaves, growth of sooty mold
• transferring Grapevine leafroll-associated
virus-3 (GLRaV-3)!
Occurrence
• in viticulture mainly in South Europe and
California
Fig.: Scagliusi et al. 2002 Fig.: Bovey et al. 1980
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Detached leaf assay with P. ficus
• spray inoculation of plants with B. bassiana
(Naturalis® 3%)
• assessment of numbers of alive mealybugs and size
every week
W 0
W 1
W 2
W 3
W 4
W 5
infestation with mealybugs
spray inoculation
1st assessment
surface sterilization
2nd assessment
3rd assessment
weeks
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Influence on insect pests
• Is any effect of endophytic B. bassiana on mortality and growth of pest insects evident?
• Are the insects influenced by endophytic B. bassiana in their host choice behavior?
Endophytic establishment of B. bassiana
• Is it possible to establish B. bassiana as an endophyte within Vitis vinifera plants?
• Is any effect of endophytic B. bassiana on plant growth of the plants evident?
Influence on plant pathogens
• Is any effect of endophytic B. bassiana on the disease severity of Plasmopara viticola evident?
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Black vine weevil Otiorhynchus sulcatus
Symptoms and damage:
• maturation feeding of adults on leaves and
flowers
characteristic crescent shaped notches
• root feeding of soil-borne larvae feed
results in wilting/stunting or could be lethal
for host plants
Host plants:
• major pest in many horticultural crops
• partly in forestry
• in viticulture mainly in grapevine nurseries
photo: HS Geisenheim
Rene Eisenbart
http://blog.oregonlive.com
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Choice assay with Otiorhynchus sulcatus
• spray inoculation of plants with
B. bassiana (Naturalis® 3%)
formulation of Naturalis® without conidia
water as control
• one adult O. sulcatus per tube
• each test lasted 1 h
• pre-test for validation of the olfactometer test system
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Choice assay – validation of the test system
control ↔ empty
p ≤ 0.05 exact binominal test
0
2
4
6
8
10
12
14
16
18
20
control no decision empty
No
. of
de
cisi
on
s
N = 35
the weevils are able to select a tube with a plant over an empty tube
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• a significant effect of endophytic B. bassiana on growth and on
mortality one week after the initial settlement of vine
mealybugs was evident
• adult O. sulcatus chose significantly more often the control
plants as a host plant compared to grapevine plants with
endophytic B. bassiana
Influence on insect pests
• Is any effect of endophytic B. bassiana on mortality and growth of pest insects evident?
• Are the insects influenced by endophytic B. bassiana in their host choice behavior?
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Influence on insect pests
• Is any effect of endophytic B. bassiana on mortality and growth of pest insects evident?
• Are the insects influenced by endophytic B. bassiana in their host choice behavior?
Endophytic establishment of B. bassiana
• Is it possible to establish B. bassiana as an endophyte within Vitis vinifera plants?
• Is any effect of endophytic B. bassiana on plant growth of the plants evident?
Influence on plant pathogens
• Is a protective effect of endophytic B. bassiana on the disease severity of Plasmopara viticola evident?
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Inoculation tests with P. viticola
treatment with B. bassiana
assessment of disease severity
inoculation with P. viticola
1
2
3
4
5
6
7
8
9
10
leaf level
day 0
day 7
day 14
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• a significant protective effect of endophytic B. bassiana on
disease severity of Plasmopara viticola is evident
• a systemic protection of the newley formed leaves could not
be observed
Influence on plant pathogens
• Is a protective effect of endophytic B. bassiana on the disease severity of Plasmopara viticola evident?
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Tritrophic interaction
pathogens e.g. Planococcus ficus, Otiorhynchus sulcatus,
Plasmopara viticola
plant Vitis vinifera
endophyte Beauveria bassiana
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Thanks for your attention!
Thanks to:
Deutsche Bundesstiftung Umwelt (DBU)
Prof. Dr. A. Reineke
Prof. Dr. H.-M. Poehling
Roman Peiter (M. Sc. Thesis)
Gordan Behaderovic (B. Sc. Thesis)
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