author(s)
Veeranna Daravath and Subhash Chander

abstract
Present study showed niche regulation between brown planthopper (BPH), Nilaparavata lugens (Stal.) and whitebacked planhopper (WBPH), Sogatella furcifera (Horvath) with regards to their natural enemy populations in early and late transplanted crop of Pusa Basmati 1121 during kharif 2015 and 2016. The BPH and WBPH populations were associated with predator population range of 20–120 predators/50 hills in early and late transplanted rice during 2015 and with 20–120 predators/50 hills in early and 20–160 predators/50 hills in late transplanted crop during 2016. With respect to predator association, BPH had broader niche in early transplanted and late transplanted crops compared to WBPH as the BPH population showed greater association with natural enemy population than WBPH during the cropping seasons of both the years. The overlap between BPH and WBPH in relation to association with predator population in early transplanted rice during 2016 was greater than 2015. The BPH thus proved to be a generalistic species compared to WBPH, which acted as more specialist species as its population occurred in lower number during the both the cropping season on rice crop.