Paddy Leaf Folder (Rice Leaf Folder)

📖 Description

Paddy Leaf Folder (Cnaphalocrocis medinalis), also called Rice Leaf Folder, is an important pest of rice across the Indian subcontinent, particularly severe in rice belts of Punjab, Haryana, Uttar Pradesh, Bihar, West Bengal, Odisha, Andhra Pradesh, Telangana, Tamil Nadu and Karnataka where rice is grown on over 44 million hectares. The larva is distinctive — it folds rice leaves with silk, creating a protective fold within which it feeds on leaf tissue, leaving characteristic white and transparent patches. Heavy infestation can cause significant defoliation, reducing photosynthetic area and yield. Outbreaks are favoured by excessive nitrogen, dense planting, continuous flooding and misuse of broad-spectrum insecticides (especially pyrethroids) that kill natural enemies — a classic example of ‘pest resurgence’ triggered by inappropriate insecticide use. The pest has become increasingly severe in recent decades due to (a) intensification of rice cultivation with high-yielding varieties that require more nitrogen, (b) misuse of broad-spectrum insecticides that kill natural enemies, and (c) climate change expanding the pest’s range. IPM with avoidance of excessive nitrogen, conservation of natural enemies (especially Trichogramma egg parasitoids and Cyrtorhinus lividipennis mirid predator), Bt applications against young larvae, hand-collection of folded leaves, and need-based selective insecticide use provides effective and sustainable control. The pest is most severe in intensively managed irrigated rice with excessive nitrogen fertilization.