Survey of stink bug (Heteroptera: Pentatomidae) egg parasitoids in wheat, soybean and vegetable crops in Southeast Virginia Amanda L. Koppel Dr. Ames Herbert, Tidewater AREC Dr. Tom Kuhar, Eastern Shore AREC
Jan 18, 2016
Survey of stink bug (Heteroptera: Pentatomidae)
egg parasitoids in wheat, soybean and vegetable crops in
Southeast Virginia
Amanda L. Koppel
Dr. Ames Herbert, Tidewater AREC
Dr. Tom Kuhar, Eastern Shore AREC
12/11/06
Outline
• Introduction– About stink bugs– Stink bugs in SE Virginia– Control
• Methodology– Field survey– Sentinel eggs
• Results– Rates of parasitism– Egg parasitoid species complex
• Discussion & Further Study
Stink Bugs (Heteroptera: Pentatomidae)
• Phytophagous and predatory species
• Pentatominae include spp. of economic importance
• Feed with stylets• Damage to plants
– Cosmetic– Growth and development– Yield and quality
Stink Bug Economic Damage of Selected US Commodities
(McPherson & McPherson, 2000)
0
5,000,000
10,000,000
15,000,000
20,000,000
25,000,000
30,000,000
(1997)
Stink Bugs in SE Virginia
• Treatment:– Economic thresholds– Pyrethroids are insecticide of choice– Stink bugs may not be seen as a threat!
• Monitoring– Blacklights– Pyramid traps– Field survey
• Most common species?
Brown stink bug
(Euschistus servus)
Green stink bug
(Acrosternum
hilare)
Biological Control of Stink Bugs
• Egg parasitoids are most common• Natural enemy surveys
– Carolinas (Jones et al. 1996)
– Louisiana (Orr et al. 1986)
– Kentucky (Yeargan 1979)
– Florida (Temerak & Whitcomb 1984)
– California (Ehler 2002)
– Brazil (Correa-Ferreira & Moscardi 1995)
Virginia Stink Bug NE Survey (2005-06 field seasons)
• Objectives– To determine if there are stink bug
natural enemies (specifically, egg parasitoids) in SE VA
– Determine rates of parasitism– Determine parasitoid species composition
Field Eggs
• Swept and visually inspected field and vegetable crops for stink bug egg masses
• Masses returned to the lab• Noted
– Parasitoids– Stink bug nymphs– No hatch
Sentinel Eggs
• From lab colony• Placed in the field
for a week– Pinned to the
underside of leaves
• Collected and returned to quarantine
• Observed as field eggs
Surveyed Eggs
Field eggs Sentinel eggsEuschistus servus 570 2336Acrosternum hilare 546 n/a
Podisus maculiventrus 15 230Murgantia histrionica 8782 n/a
Total: 12, 479 eggs
Percent Parasitism
E. servus eggs
40%
22%
38% # parasitized
# no hatch
# SB nymph hatch
(cont.)
A. hilare eggs
20%
35%
45%# parasitized
# no hatch
# SB nymph hatch
(cont.)
P. maculiventrus eggs
12%
41%
47%
# parasitized
# no hatch
# SB nymph hatch
(cont.)
M. histrionica eggs10%
38%52%
# parasitized
# no hatch
# SB nymph hatch
Parasitoid IDs
• All Hymenoptera• Mymaridae• Scelionidae-- Telenomus and Trissolcus• Used keys by N.F. Johnson, Ohio State
E. servus-- Telenomus podisi
M. histrionica-- Trissolcus basalis & a Mymarid
A. hilare
Not pictured: Trissolcus euschisti
Trissolcus eddesae
Trissolcus basalis
Not So Generalist?
• Egg parasitoids tended to stick to certain host species
• Some crossover• Stink bug host crop was irrelevant
Significance
• Great deal of heretofore unknown biological control in VA– Meaning to farmers– Effect of chemical sprays on
parasitoid oviposition• Parasitization in both 1st and 2nd
generations• Choice testing of Telenomus podisi
THANK YOU!!
• Faculty:– Dr. Douglas Pfeiffer– Dr. Scott Salom– Dr. Kim Hoelmer, USDA-ARS-BIIR
• Graduate Students– Kathy Kamminga, SB Survey Data
Questions?