Native Isolates of Purpureocillium lilacinum Against Cassava Mealybug Phenacoccus manihoti Matile- Ferrero

Cassava mealybug, Phenacoccus manihoti is a noxious pest on cassava. A pot culture experiment was taken up to evaluate the bioefficacy of two native isolates of Purpureocillium lilacinum (EPF 3 and EPF 7) against Phenacoccus manihoti in cassava at the concentration of 1×10⁸ spores ml^-1. Efficacy of these isolates were evaluated and compared with NBAIR isolate of Lecanicillium lecanii @ 1×10⁸ spores ml^-1, neem oil emulsion (2%) and dimethoate 30 EC @ 1.5 ml L^-1. Maximum reduction in the mealybug population was observed in dimethoate treated plants. Among the fungal isolates, significantly higher reduction in population was observed in P. lilacinum, EPF 7 (78.55%) followed by P. lilacinum, EPF 3 (74.92%). NBAIR isolate of L. lecanii recorded 70.24% reduction in mealybug population. The present study revealed that biological control of cassava mealybug, P. manihoti using two promising isolates of P. lilacinum could be a viable alternative to chemical insecticides.