UTTAR PRADESH JOURNAL OF ZOOLOGY

Rice (Oryza sativa L.) is a major staple crop in Asia, but its productivity is severely threatened by planthopper pests, especially the brown planthopper (Nilaparvata lugens Stål) and white-backed planthopper (Sogatella furcifera Horváth), which cause significant yield losses through sap feeding and “hopper burn.” A field experiment was conducted at the Regional Agricultural Research Station, Warangal, Professor Jayashankar Telangana Agricultural University, Telangana, India, during Kharif and Rabi, 2018–19 to evaluate the bio-efficacy of benzpyrimoxan + thiamethoxam (10 + 3.3% SC) against brown planthopper (BPH) and white-backed planthopper (WBPH) in rice, along with its safety to natural enemies. Ten treatments comprising different doses of benzpyrimoxan + thiamethoxam (10+3.3% SC) (65+21.4 to 150+50 g a.i. ha⁻¹), standard insecticidal checks, and an untreated control were evaluated in a randomized block design with three replications. The premix formulation effectively suppressed both planthopper species during both the seasons, with higher doses (100+33 to 150+50 g a.i. ha⁻¹) providing sustained control up to 15 days after spray. The dose of 75+25 g a.i. ha⁻¹ also recorded comparable efficacy, indicating flexibility in dose selection. The highest grain yields were obtained with 150+50 g a.i. ha⁻¹ (5700 and 4895 kg ha⁻¹ during Kharif and Rabi, respectively), which were statistically at par with yields recorded at 75+25 to 125+41.25 g a.i. ha⁻¹, suggesting limited yield advantage beyond moderate doses. No phytotoxic symptoms were observed, and populations of spiders, coccinellids, and mirid bugs remained comparable to untreated plots, indicating safety to natural enemies. Overall, benzpyrimoxan + thiamethoxam (10+3.3% SC) @ 75+25 g a.i. ha⁻¹ demonstrated effective and economic management of planthoppers with improved yield and ecological safety, and may be considered a promising option under similar agroecological conditions.