Indian Journal of Entomology

Spatial distribution of rice planthoppers, Nilaparvata lugens (Stal) and Sogatella furcifera (Horvath) together, rice leaf folder Cnaphalocrocis medinalis (Guenee) and their predators was studied during kharif, 2010, using standard normal variable (d), discrete frequency distributions viz., Poisson, binomial and negative binomial, and regression models viz., Taylor's power law and Iwao's mean crowding regression. Planthoppers had aggregation as dominant type of distribution pattern, while leaf folder followed random distribution during most of crop growth stages. Spiders, mirid bugs, rove beetles and coccinellids were observed to follow aggregated distribution on the crop, while carabids were dispersed in random manner. Predators were observed to follow distribution pattern of their prey species. Information on spatial distribution of pests and their effective predators would be helpful in ensuring better management decisions.