EFFECT OF DIFFERENT CONCENTRATIONS OF BEAUVERIA BASSIANA ON DEVELOPMENT AND REPRODUCTIVE POTENTIAL OF SPODOPTERA LITURA (FABRICIUS)

ABSTRACT Beauveria bassiana,the most common and ubiquitous fungal entomopathogen is known to be highly potent for the control of insects belonging to various orders. The virulence of B. bassiana was tested against second, third and 4th instar larvae of S. litura using three concentrations i.e. 2.03 × 108, 4.03 × 106 and 1.47 × 105 spores/ml. All the treatments resulted in significantly higher mortality than control. Besides mortality, sublethal effects were also evaluated on larvae that survived fungal infection. Significant decrease in larval period was observed due to infection as compared to control. The life span of females emerging from treated larvae was half that of the control females. In addition to this, inhibitory effects were also manifested as reduced reproductive potential. The eggs descended from treated larvae showed significant decrease in hatchability. B. bassiana also induced pupal and adult deformities. A significantly higher number of deformed adults were observed at lower concentrations as compared to the highest concentration.