EFFECT OF INOCULATION TECHNIQUE AND ADDITION OF LARVAL EXTRACT TO PDA MEDIUM ON THE VIRULENCE OF BEAUVERIA BASSIANA AGAINST SPODOPTERA LITURA (L.)

Spodoptera litura Fabricius is an important pest that attacks crops and vegetables in Indonesia. Beauveria bassiana has the potential as a biological control agent. This research aimed to evaluate the effect of adding S. litura larvae extract (compared to control without larvae extract) in PDA medium combined with different types of inoculation techniques (leaf spray, larval spray, leaf dyeing, and larval dyeing) on fungal virulence B. bassiana against S. litura larvae. This research using 20 larvae of S. litura 2^th instar for each treatment. The treatment includes eight combinations of inoculation techniques and the addition of larvae extract on a culture medium of B. bassiana. The highest S. litura mortality (71.67%) on PDA medium with larval extract and the larvae was dipped in a suspension of conidia. The lowest S. litura mortality (45.00%) on PDA medium without the addition of larval extracts and a suspension of conidial was sprayed onto the leaves. The shortest LT50 value (4.58 days) on PDA medium with larval extract and the larvae were dipped in a suspension of conidia. The longest LT50 value (8.09 days) on PDA medium without the addition of larval extracts and a suspension of conidial was sprayed onto the leaves as larvae diet.