Efficacy of fungal pathogens, Fusarium semitectum Berk. and Ravenel and Hirsutella thompsonii Fisher against red spider mite, Tetranychus neocaledonicus (Andre) on okra under laboratory and field conditions

Efficacy of fungal pathogens, Fusarium semitectum Berk. and Ravenel and Hirsutella thompsonii Fisher was evaluated against red spider mite, Tetranychus neocaledonicus (Andre) of okra under laboratory and field conditions. The results showed that the highest mortality of 78.20 and 88.34 per cent adults and immatures, respectively was recorded at 2.10 x10⁹ spores per ml of F. semitectum where as it was 82.05 and 92.31 per cent adults and immatures, respectively in case of H. thompsonii at4.60x10⁸spores perml. Amongthetwelvetreatments evaluatedunderfieldconditions, F. semitectum 2.60 x 10¹⁵+ H. thompsonii 4.10 x10¹⁴spores per ml + dicofol 0.025%, H. thompsonii 4.10 x10¹⁴spores per ml + dicofol 0.025% and F. semitectum 2.60 x 10¹⁵+ H. thompsonii 4.10 x 10¹⁴spores per ml + Econeem 0.002% were found to be superior to other counterparts with a mortality of 76.37, 75.00 and 69.53 per cent, respectively. Even though active stages of T. neocaledonicus were susceptible to infection of both F. semitectum and H. thompsonii under laboratory and field conditions, H. thompsonii was found to be more effective than F. semitectum in managing them.