Abstract

                                In-vitro efficacy tests of Disfect-S (Poly alkyl monohydric phenol) on the viability of infective propagules of silkworm disease at varying concentrations of 0.2%, 0.4%, 0.6%, 0.8%, 1.0%, 2.0% & 3.0% were carried out. Efficacy of 'Disfect- S as surface sterilant of silkworm eggs was tested at concentrations of 0.2%, 0.4%, 0.6%, 0.8% and 1.0% with treatment durations of 1 min, 2 min, 5 min, 10 min and 20 min. The viability and the infectivity of Nosema bombycis spores was inactivated at 0.4% with 5 min. of treatment duration and the infectivity of conidia of Beauveria bassiana was completely arrested at 0.8% with 5 min. duration whereas Nuclear polyhedra virus (BmNPV) were completely inactivated at 0.8% for 10 minutes treatment duration. Disfect-S was highly effective as surface sterilant of silkworm eggs at 0.4% with 2 min. duration treatment without any deleterious effect on hatching. The present study gives an higher scope for Disfect-S as potential commercial disinfectant in sericulture.

Key words : Silk worm pathogens, Disinfectants