Influence of abiotic factors on seasonal incidence of pests of tasar Silkworm Antheraea mylitta D.

Abstract

Rearing of tropical tasar silkworm, Antheraea mylitta Drury is mainly conducted in outdoor on Terminalia tomentosa W. & A. a nature grown primary host plant available in forest and also on raised primary host plant Terminalia arjuna Bedd. Temperature, relative humidity and rainfall are the main environmental factors for occurrence of pests (parasites and predators) of tasar silkworm during I, II and III crop rearing in the tropical tasar producing zones. The present study was aimed to study the influence of abiotic factors on prevalence of tasar silkworm pests. The study was conducted at different agro-climatic regions viz., Central Tasar Research &Training Institute, Ranchi, Jharkhand, Regional Extension Centre, Katghora, Chattisgarh and Regional Extension Centre, Hatgamaria during 2010-13 covering 3 seed crop and 6 commercial crops. Data on incidence of tropical tasar silkworm endo-parasitoids like Uzi Fly, Blepharipa zebina Walker and Ichneumon fly (Yellow Fly), Xathopimpla pedator, Fabricius and Predators such as Stink bug (Eocanthecona furcellata Wolf), Reduviid bug (Sycanus collaris Fabricius) and Wasp (Vespa orientalis Linnaeus) was recorded Weekly. The meteorological data was collected daily. Data was collected from 4 different agro-climatic zones of tasar growing areas. Analysis of the data revealed a significant negative correlation between abiotic factors and incidence of ichneumon fly and uzi fly. Based on the 3 years data on prevalence of pests region-wise pest calendars and prediction models were developed.