Seasonal Incidence and Extent of Parasitization of Fruit Piercing Moths of the Genus Othreis(Lepidoptera: Noctuidae)

Abstract

Four egg and three larval parasitoids were recorded on Othreis spp. Mean per cent parasitization of eggs of Othreis by Trichogramma chilonis Ishii and Telenomus sp. during 1998 was 21.45±27.45 (range 0-80 %) and 6.57±11.56 (range 0-50 %) and during 1999 was 50.40±34.08 (range 0-100 %) and 4.93±8.99 (range 0-31.9 %), respectively. Parasitisation by egg parasitoids, Ooencyrius papilionis Ashmead and Anastatus sp., was negligible. In nature. Euplectrus indicus Ferriere parasitised the fifth instar larvae of O. materna whereas E. maternus Bhatnagar parasitised first to third instars of O. materna, O. fullonia and O. homaena. Mean per cent parasitization ofO. materna, O. fullonia and O. homaena larvae by E. maternus was 20.7±10.9 (range 0-30 per cent), 19.46±18.71 (range 0-50 per cent) and 1.66±3.33 (range 0-8.33 per cent), respectively in the field. In the laboratory, E. indicus parasitized fourth or fifth instar caterpillars of Othreis and laid 38-97 eggs on the dorsum in between posterior eye spots on the third abdominal segment of the host. The parasitoid paralysed the host before oviposition. Total development from egg to adult emergence took 15 -17 days. The tachinid, Winthemia sp. parasitized only the fifth instar of O. materna. Eggs were laid on the lateral side of prothorax. On hatching, the maggots directly entered the host body by cutting the skin just below the egg attachment. The maggot development continued until the host caterpillar pupated. Full grown larvae came out from the host pupa through a hole and pupated either in soil or in leaf debris. Both E. maternus and Winthemia sp. have the potential for the suppression of population of species of Othreis