Biocontrol Science and Technology (2014) 24, 133-144

Md.Abdul Alim and UnTaek Lim (2014)
Ecotoxicological effect of insecticides on Ooencyrtus nezarae (Hymenoptera: Encyrtidae) reared from refrigerated and unrefrigerated Riptortus pedestris (Hemiptera: Alydidae) host
Biocontrol Science and Technology 24 (2), 133-144
Abstract: Due to increased field occurrence of Riptortus pedestris (Fabricius) (Hemiptera: Alydidae) on various crops including soybean, persimmon and apple in recent years in Korea, demand for insecticide applications to control the stink bug has increased. Acute toxicity of eight pesticides on Ooencyrtus nezarae Ishii (Hymenoptera: Encyrtidae), a major egg parasitoid of R. pedestris, was compared in the laboratory. Fenitrothion, spinosad, cyfluthrin, etofenprox and carbosulfan caused 100% mortality of O. nezarae within 24 hours by topical application or exposure to residue. Fenitrothion was also highly toxic to the parasitoid when ingested orally. In a previous study, release of refrigerated inviable eggs of R. pedestris was found to increase field parasitism; therefore, we evaluated the sublethal effect of fenitrothion when O. nezarae parasitised refrigerated or unrefrigerated host eggs. Although parasitism rates on both kinds of eggs significantly decreased when O. nezarae were provided with host eggs sprayed with fenitrothion, no difference in parasitism rate, adult emergence, sex ratio, development time and longevity of O. nezarae was found between the refrigerated or unrefrigerated host eggs when the insecticide was treated either before or after oviposition. There was no significant sublethal effect when parasitised host eggs were treated with the insecticide. From these results, all the insecticides tested showed high, acute toxicity against O. nezarae with relatively lower sublethal effects. Refrigeration of host eggs did not affect the susceptibility of O. nezarae to insecticides.
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Link to article at publishers website
Database assignments for author(s): Un Taek Lim

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
resistance to pesticides
formulation/storage of bioagents

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Riptortus pedestris	Apple (Malus)	Korea-South
	Riptortus pedestris	Soybean (Glycine max)	Korea-South
	Riptortus pedestris	Persimmon (Diospyros)	Korea-South
Ooencyrtus nezarae (parasitoid)	Riptortus pedestris