Monitoring of insecticide resistance in Rice brown planthopper Nilaparvata lugens (Stål) in Nalgonda District of Telangana State, India

Insecticide resistance development was monitored in the rice brown planthopper (BPH) Nilaparvata lugens, field population collected from Nalgonda district, Telangana state, during 2015. The results indicated that BPH population from Nalgonda district acquired very high level of resistance to buprofezin 25 SC (1409 fold) and neonicotinoids such as imidacloprid 17.8 SL (352 to 661 fold). High level of resistance to thiamethoxam 25 SG (50 to 138 fold) and glamore 80 WG (ethiprole 40% + imidacloprid 40% WG) (222 to 431 fold) was also observed. However, the population was suseptible to dinotefuran 20 SG (RR 1.5 to 3.6) and organophosphorous compounds such as monocrotophos 36 SL, dichlorvos 76 EC, chlorpyriphos 20 EC and acephate 75 WP (RR 0.28 to 2.02). For insecticides belonging to other groups such as phenyl pyrazoles i.e. fipronil and pyridine azomethine compound i.e. pymetrozine, the resistance ratios (RR) were in the order of 1.4 to 1.9 and 1.19 to 1.59, respectively. Insecticide resistance management strategies are described in brief.