BIOLOGY OF TWO SPOTTED SPIDER MITE, TETRANYCHUS URTICAE KOCH. (ACARI: TETRANYCHIDAE) ON MULBERRY, MORUS SP.

Abstract

Mulberry, Morus sp. is a tropical evergreen plant and their leaves are the only sole food for the mulberry silkworm, Bombyx mori due to the presence of some secondary plant metabolites like morin, β sitosterol and other alkaloids. The quality of the mulberry leaves is an important factor for the success rate of sericulture industry. As mulberry plant has excellent greenish foliage which acts as a susceptible host for many pests. Among various pests, the two-spotted spider mite, Tetranychus urticae Koch. acts as a major pest in the mulberry ecosystem as it affects the leaves quality by sucking the sap content in it. The two-spotted spider mite is a polyphagous sucking pest and dominant mite species reported in green house and field condition, which can survive even in high temperature. The biology of two-spotted spider mite was studied on mulberry leaves (var. MR 2) under laboratory condition (27±5°C and 70±5% R.H.) during March, 2019 at Department of Entomology, Faculty of Agriculture, Annamalai University. The present paper adumbrates the duration of different developmental stages such as egg, larvae, protonymph, deutonymph, developmental period, oviposition period and adult longevity (male and female) of two spotted spider mites on mulberry. The higher temperature increases the developmental rate and reduces the duration of developmental stages. The present finding from this research paves way for the selection of appropriate IPM module for the effective management of two spotted spider mite on mulberry.