Role of the parasite, Rhoptromeris sp., in the control of lemon fruit borer.
A eucoilid parasite, Rhoptromeris sp., is believed to play an important role in the natural control of Citripestis sagittiferella Moore on lemon in the orchard at Universiti Pertanian Malaysia in Serdang, West Malaysia. From laboratory examination of field-collected larvae, the rate of parasitism was estimated as 24%. Field tests of emulsion sprays containg 0.1% malathion showed that the percentages of fruits attacked were higher and the numbers of adult parasites lower on treated than on untreated trees, and that the changes in the degree of fruit infestation were strongly correlated with the abundance of the adult parasites. Possible corrective measures to reduce the harmful effects of insecticide applications to parasites are discussed.