Effect of Antidesiccants on Survival and Pathogenicity of Some Indigenous Isolates of Entomopathogenic Nematodes Against Plutella xylostella (L.)

The antidesiccant property of glycerin, liquid paraffin, triton X 100, tween 80 and castor oil for survival and pathogenicity of entomopathogenic nematodes against Plutella xylostella was evaluated. These were not found to be adversely affecting the survival of IJs. The infectivity of IJs of nematodes against P. xylostella was improved by antidesiccants at 0.25, 0.5 and 1% concentrations on cabbage leaf discs when exposed to 310C and 60% RH and were significantly effective as compared to control. Irrespective of nematode species tested, IJs exposed for 1 and 2 hrs resulted in absolute mortality of P. xylostella at 0.5 and 1% concentrations of glycerin and liquid paraffin, respectively. Triton X 100 and Tween 80 protected the IJs from desiccation at higher concentrations for 1 and 2 hrs only. Castor oil offered least protection among the antidesiccants tested. Glycerin and liquid paraffin at 0.5 and 1% concentrations offered maximum protection and could be utilized as effective antidesiccants in foliar sprays of nematodes.