Eco-friendly Strategies for the Management of Rice Leaffolder, Cnaphalocrocis medinalis Guenee

Field release of egg parasitoid, Trichogramma chilonis Ishili (Hymenotera, Trichogrammatidae) and applications of Bacilus thuringiensis (Bt) var. galleriae, buprofezin 25 WP, neem seed kernal extract (NSKE) and monocrotophos 36 WSC were evaluated for control of rice leaffolder, Cnaphalocrocis medinalis on two rice varieties under irrigated ecosystem. The leaffolder damage in untreated plots were 13.1% and 21.8% whereas in treated plots in varied from 4.4% -11.2% and 7.2% -17.1% in kharif and rabi seasons respectively. 4 to 6 releases of T chilonis (1 lakh/ha) followed by ETL based application of Bt (2.5 L/ha), NSKE (5%), buprofezin 25 WP (1.6 kg/ha) and monocrotophos (1.0 L/ha) alone or in combination effectively reduced leaffolder damage and gave higher grain yield in comparison to untreated plots. The four inundative releases of T. chilanis followed by ETL based on 3 sprays of monocrotophos was found to be superior in recorded less leaffolder damage (4.4%) and highest grain yield (6.1 t/ha) but relatively toxic to natural enemies of rice ecosystem, Harmonia octomaculata, stphylinid beetle, Paederus fsucipes, spiders viz. Lycosa psudoannulata and Tetragnatha javana. Either 6 releases of T chilonis alone or 4 releases of the egg parasitoid followed by application of Bt. NSKE and buprofezin alone or in combination significantly reduced leaffolder damage and gave higher grain yield compared to control plots.