Efficacy of non formulated entomopathogenic fungi (Beauveria bassiana) to control the storage insect pests of green gram (Vigna radiata) seeds

Abstract

The concepts and practical applications of fungal biotechnology continue to make significant contributions to food science. Storage of grains is part of the post-harvest system through which food material passes on its way from field to consumer. Stored pulses are severely infested by beetles of the family Bruchidae (Coleoptera). The present study was focused on the efficacy of microbial pesticides, i.e entomopathogenic fungus (Beauveria bassiana) on the Callosobruchus species were investigated in laboratory in stored green gram (Vigna radiata) seeds. Four different conidial concentrations of B. bassiana were sprayed (1 mL) based on the logarithmic series (4×102, 4×103, 4×104 and 4×105 conidia mL-1) and incubated for 10 days. Twenty four experiments were conducted with a complete randomized block design (CRD) with three replications. B.bassiana, concentration of, 4×105 conidia mL-1 at exposure day 10 gave maximum (99.00 %) insect mortality, moisture content of seed was 11.48% and protein content was 24.5%. Optimally fungal treated samples were devoid of any mycotoxins thereby implying their safety for human consumption. The results indicated that the fungal treatment retain the germination quality of seed. This study provided a novel and environmentally safe technique.