Bioefficacy of Actinomycetes Secondary Metabolites against Maruca vitrata (Geyer) in Pigeonpea

Secondary metabolites of seven actinomycetes isolates were tested for their insecticidal activity against second instar larvae of Maruca vitrata using diet impregnation and detached flower bioassay. In diet impregnation bioassay mortality rates recorded by KAI-26, MMA-32, SAI-13, CAI-93, CAI-21, SAI-25 and KG-13 were 90.90%, 90.90%, 81.81%, 63.63%, 54.54%, 51.51% and 18.18%, respectively. In detached flower bioassay mortality rates shown by MMA-32, KAI-26, SAI-13, SAI-25, KG-13, CAI-21 and CAI-93 were 94.44%, 94.44%, 88.88%, 72.22%, 44.44% and 33.33%, respectively. Isolates which showed highest efficacy in both diet impregnation and detached flower bioassay were further evaluated in glass house. Glass house studies revealed that KAI-26, MMA-32 and SAI-13 maintained the same performance with 90.90% mortality. The effective isolates against M. vitrata were KAI-26, MMA-32 and SAI-13.