Potential of Lecanicillium lecanii (Zimm.) as a Microbial Control Agent for Green Peach Aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae)

The utilization of entomopathogenic fungi as potential microbial control against different insect pests is important due to their eco-friendly nature. The virulence potential of 3 different isolates of Lecanicillium lecanii formerly recognized as Verticillium lecanii (V-2, V-3 and V-5) with different bioassay materials (conidia, filtrate and the binary combination of conidia + filtrate) were evaluated against green peach aphid (Myzus persicae) under control condition. Conidial bioassay of fungal isolates were evaluated with three different concentrations (1x10(6), 1x10(7) and 1x10(8) conidia/ml), filtrate bioassay was estimated by applying 7th day fungal filtrate and binary combination (1ml conidia +1ml filtrate) of V2xV2, V3xV3 and V5xV5 were tested against M. persicae. Mortality data were recorded after 2, 4, 6 and 8 days post-treatment. In conidial bioassay, V-3 showed maximum aphid mortality (95%) and V-5 showed the lowest mortality (70%) at the highest concentration (1x10(8) conidia/ml) at 8th-day post-treatment whereas, in filtrate bioassay, 98% mortality was achieved in V-3, and recorded mortality up-to 74% in V-5. Similarly, in the binary combination of fungal conidia 1x10(8) conidia per ml and its filtrate, combination (V-3xV-3) revealed the highest M. persicae mortality 91%, while combinations, V-2xV-2 and V-5xV-5 resulted in lowest M. persicae mortality 79% and 65%, respectively. The results revealed that in all types of bioassays, V-3 isolate was the most virulent and its filtrate application was found to be the most effective against M. persicae.