BioControl (2008) 53, 857-867

Johanna Häckermann, Anja S. Rott, Kathrin Tschudi-Rein and Silvia Dorn (2008)
Cold stored ectoparasitoid of Cydia fruit moths released under different temperature regimes
BioControl 53 (6), 857-867
Abstract: Cold storage of parasitoids to be used in biological control programs is desirable but risky for the performance of the stored parental generation as well as for its offspring. We studied the performance of cold stored and unstored parasitoids after release at different temperature regimes in the laboratory at the level of two subsequent generations in Hyssopus pallidus (Askew) (Hymenoptera: Eulophidae). This gregarious ectoparasitoid is a candidate biocontrol agent of Cydia pomonella L. (Lepidoptera: Tortricidae) and Cydia molesta (Busck) (Lepidoptera: Tortricidae) larvae, two fruit pests of high economic significance in apple cultivation. Cold storage for 14 days at 4°C imposed to the pupal stage of the parasitoid did not reduce the parasitism capacity of the parental generation, nor did it alter the female biased sex ratio of the progeny. Remarkably, this short-term storage of the parental generation exhibited a significant and consistently positive effect on offspring weight throughout all ambient temperature regimes, resulting in an increased offspring weight. Furthermore, offspring number was only reduced after release at low ambient temperatures, but not at 25°C and 30°C. Irrespective of whether the parasitoids originated from the stored or unstored group, highest parasitism rate was achieved at temperatures above 20°C. In conclusion, this candidate biocontrol agent can be cold stored for short periods without any measurable quality loss after release at most except at low ambient temperatures. Our findings suggest that H. pallidus is a thermophilous parasitoid that will perform best when applied at warm ambient temperatures in fruit orchards.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Silvia Dorn

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation
rearing/culturing/mass production

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Cydia pomonella
Hyssopus pallidus (parasitoid)	Cydia pomonella