Entomologia Sinica (2001) 8, 251-257

Xiao-Ping Yu and Takashi Wada (2001)
The preference and density responses of egg parasitoid, Ooencyrtus nezarae Isho, to the eggs of soybean stick bugs, Riptortus clavatus Thunberg and Piezodorus hybneri Gmelin
Entomologia Sinica 8 (3), 251-257
Abstract: The preference and density response test9 of egg parasitoid, Ooencyrtus nezarae Ishii, to the eggs of soybean stick bugs, Riptortus clavatus Thunberg and Piezodorus hybneri Gmelin, were carried out in this study. In the free choice test, O. nezarae emerged from both eggs of stick bug prefer R. clavatus eggs only in the various ratios of host egg densities. In non-choice test, O. nezarae emerged from P. hybneri eggs parasitize both R. clavatus and P. hybneri eggs, showing a high parasitism on host eggs. However, O. nezarae reared on R. clavatus eggs had a significantly lower parasitism on the eggs of P. hybneri. Olfactometer test showed that the odor emitted from R. clavatus eggs had a great influence on the host searching and parasitizing behavior of O. nezarae. The number of R. clavatus and P. hybneri eggs parasitized by O. nezarae gradually increased with the increase of host egg densities. However, the parasitism of O. nezarae to R. clavatus eggs decreased with the increase of host density. The parasitism of O. nezarae are significantly lower (P < 0.05) on host egg P. hybneri under the laboratory condition, especially for O. nezarae emerged from R. clavatus eggs. This research results implied that in the soybean field, there were some optimal or spatial barriers for O. nezarae to find R. clavatus eggs efficiently.
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Link to article at publishers website
Database assignments for author(s): Takashi Wada

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Riptortus pedestris	Soybean (Glycine max)
	Piezodorus hybneri	Soybean (Glycine max)
Ooencyrtus nezarae (parasitoid)	Riptortus pedestris
Ooencyrtus nezarae (parasitoid)	Piezodorus hybneri