Effect of Beauveria bassiana (Bals.) with botanical extracts against Trogoderma granarium (Everts.) under laboratory conditions

Abstract

Worldwide, stored grain products are severely harmed by the khapra beetle, Trogoderma granarium (Bals.) (Coleoptera: Dermestidae), It results in significant losses for wheat, Triticum aestivum (Linn.). The goal of the current experiment was to determine how well three plant extracts moringa, lupin, and lemon grass and fungus Beauveria bassiana (Bals.) worked against T. granarium larvae. Fungal formulation was formulated at 0.3×10⁸, 0.6×10⁸, and 0.9×10⁸ conidia kg^-1 of crushed wheat grains. In a lab conditions with 30±2ºC and 65±5% relative humidity (r.h), it was also combined with each plant extract. Combination dosages of the plant extracts and the fungal conidial formulation caused the greatest amount of larval mortality when compared to their solo treatments. Combination treatment of B. bassiana (0.9×10⁸ conidia kg^-1) with lemon grass extract resulted in highest larval death rate (71.22%). Furthermore, highest concentration of B. bassiana (0.9×10⁸ conidia kg^-1) alone caused a higher percentage of T. granarium larval death (57.63%) compared to the extracts from lupin and moringa plants (37.36 and 43.94%, respectively). When B. bassiana was applied separately from the plant extracts, the insect larvae showed a much higher maximal rate of mycosis and sporulation. In treatment, lowest concentration of B. bassiana (0.3×10⁸ conidia kg^-1) was only utilized, resulting in the observation of mycosis (53.33%) and sporulation (140 conidia kg^-1). Thus, it was determined that the combined usage of fungus and plant extract might be beneficial for T. granarium's integrated pest control program.