Abstract

                                The in-vitro study on the biology of two spotted spider mite Tetranychus urticae Koch. on some of the preferred host plants viz., okra, egg plant, french bean, pumpkin, tomato, tapioca and mulberry revealed that the egg, larval, protonymphal and duetonymphal stages, adult longevity, pre-oviposition period and post-oviposition period were the shortest on okra followed by egg plant, french bean, tomato, tapioca, pumpkin and mulberry. The oviposition period, sex ratio and the fecundity were more and prolonged on okra followed by egg plant, french bean, tomato, tapioca, pumpkin and mulberry. T. urticae showed relatively better performance on okra, which might be attributed to increased level of total chlorophyll, total sugars, protein and lesser wax content, phenol and silica compared to rest of the host plants.

Key words : Biological parameters, Host plants, Population, Tetranychus urticae