A roving survey was conducted in the rice crop grown in coastal districts of Andhra Pradesh during rabi, 2021-22 and 2022-23. Overall mean stem borer incidence varied from 13.59% - 14.83% in both the seasons. Larvae of Scirpophaga incertulas (Walker), Sesamia inferens (Walker), Chilo polychrysus (Meyers) and Chilo auricilius (Dudgeon), were recorded from four districts during the survey. Among the stem borers, S. incertulas was the most predominant species (53.37%) followed by S. inferens (44.7%). Natural larval parasitization (21%) of S. inferens by Cotesia flavipes Cameron was observed in West Godavari district. The biology of S. inferens was studied on rice cv. MTU 1121. The average larval period recorded was 32.40± 0.35 days. Total life cycle of S. inferens ranged between 41-65 and 46-73 days for male and female moths, respectively. Current study suggests that S. inferens could be a potential threat to rice cultivation in coastal Andhra Pradesh.
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