Survival and pathogenicity of native Heterorhabditis sp. (Rhabditida: Heterorhabditidae) as influenced by soil temperature, moisture and relative humidity

The studies on the survival and pathogenicity of locally isolated Heterorhabditis sp. was carried out in laboratory by simulating the various parameters viz., soil temperature, soil moisture and relative humidity, in sandy loam soil collected from Chidiyatapu, South Andaman. It was found that for the survival and pathogenicity of Heterorhabditis rp. eight per cent soil moisture and temperature of 24°C at a relative humidity of 100% resulted in mean pathogenicity of 75.27%. Moisture levels above or below 8% and temperatures above or below 24°C at 100% relative humidity led to decrease in survival and virulence of nematodes. The survival and pathogenicity of nematodes declined as the time progressed.