Efficacy of Newer Insecticide Molecules for the Management of Emerging Pests of Rice in the Cauvery Delta Zone of Tamil Nadu, India

Seven treatments including 5 insecticides, Azadirachtin and untreated control were evaluated in field conditions against emerging pests of Rice viz., Rice hispa, Dicladispa armigera, (Oliver), (Chrysomelidae: Coleoptera), Whorl maggot, Hydrellia sasakii Yuasa and Isitani (Diptera: Ephydridae) and Rice black bug, Scotinophara lurida (Burmeister),(Pentatomidae: Hemiptera) during 2019 and 2020 at Tamil Nadu Rice Research Institute, Aduthurai. All the tested newer insecticide molecules were effective against the above-mentioned emerging pests of Rice. Two sprays of Chlorantraniliprole 18.5% SC @ 150ml/ha at 35 and 75 days after transplanting (DAT) has reduced the highest reduction of hispa, whorl maggot and black bug (91.80, 92.25, 84.51 percent reduction over control) followed by Clothianidin 50 WDG @ 40g/ha (88.46, 89.60 and 83.39 percent reduction over control). Higher yield was recorded from Chlorantraniliprole 18.5% SC (6075 kg/ha) treated plots followed by Clothianidin 50 WDG @ 40g/ha (5950 kg/ha). Cost-benefit analysis showed that Chlorantraniliprole 18.5% SC @ 150ml/ha spray was the most viable treatment by recording the highest cost-benefit ratio of 1: 3.17. Chlorantraniliprole 18.5% SC @ 150ml/ha recorded more number of spiders and coccinellids (1.51 and 1.75 no./plant) followed by Carbosulfan 25% EC @ 1000ml/ ha (1.40 and 1.75 no./plant) which was on par with control (2.98 and 2.88 no./plant).