Submitted to: Entomological Research (Korea)
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/7/2006
Publication Date: 3/12/2007
Citation: Lee, J., Pemberton, R.W. 2007. Seasonal phenology and age specific parasitism in the Apple Ermine moth in Korea. Entomological Research (Korea). 37:59-64. Interpretive Summary: The Apple Ermine moth is a tent caterpillar which is pest of cultivated apples in western North America. The moth is well regulated by parasitoids in its native Korea. To better understand this regulation we examined the stages attacked and used during the development of the parasitoids and when they were occured during the activity period of the moth. Ageniaspis fuscicollis, a parasitoid which develops in the egg through the larval stages, causes the most mortality to the first instar larval- 24%. Dolichogenidea delecta was found in all larval instars but causes the most mortality in the second and mid (four-fifth instars) larval groups-about 20% Herpestomus brunicornis Grav was reared from second instar larvae through pupae and caused the most mortality in pupae- 29.9%. Zenillia dolosa (Meigen) was recovered from mid larval to pupal stages and caused the highest parasitism - 5.5% in the mid larval group. The host stages for developing A. fuscicollis overlap with those used by D. delecta, and H. brunicornis to some degree. A statistically significant negative correlation exists between occurrence of A. fuscicollis and these dominant parasitoids, indicating that they competitive within the host. This better understanding of the stage specific parasitism and the mortalities induced can improve the use of these parasitoids for biological control of Apple Ermine Moth.
Technical Abstract: The apple ermine moth (AEM), Yponomeuta malinellus Zell. (Lepidoptera: Yponomeutidae) is a tent caterpillar that feeds on Malus spp. in Korea. AEM populations in the native areas appeared to be regulated by assemblage of parasitoids. Phenological associations between host stages and parasitoids, susceptible stage(s) of the host for each parasitoid, and stage specific parasitism were studied. The egg larval parasitoid Ageniaspis fuscicollis (Dalman) produced the highest parasitism (24%) of first instar larvae with its parasitism of 14% of other larval stages. Dolichogenidea delecta (Haliday) was recovered from all larval instars with the highest parasitism rate of 20.1% of 2nd instar larvae and the second highest parasitism of 19.9% of mid-larval hosts. Herpestomus brunicornis Grav. was reared from 2nd instar larval through pupal collection with the highest parasitism rate of 29.9% of the pupal stage. The larval pupal parasitoid, Zenillia dolosa (Meigen) was recovered from mid larval to pupal stages with the highest parasitism rate 5.5% occurring in 3-4th instar larvae. The host stages for developing A. fuscicollis completely overlap with those used by D. delecta, and H. brunicornis to some degree. A statistically significant negative correlation exists between A. fuscicollis and these dominant parasitoids, indicating competitive interaction within the host