Appraisal of some granular insecticides against yellow-stem borer and Crop Water Productivity of Rice under two irrigation regimes

Insect pests are serious threat to agricultural crops. Recurrent use of similar chemicals has resulted in many problems like resistance development in insects and hazardous effects on environments. The present research work was executed to probe out the comparative efficacy of some newer granular insecticidal formulations against yellow stem borer of rice, Scirpophaga incertulus (Walker). Recommended dose rates of the selected insecticides were used against the targeted insect pest. Results of incidence of S. incertulus larvae on paddy tillers showed that highest mean number population (22.40 larvae) were noted in experimental plots under flood irrigation compared with AWD irrigated plots (12.36 larvae). Data regarding dead-hearts revealed that maximum (8.5 dead-hearts /plot) were recorded in control followed by Cartap Hydrochloride (4.2 dead-hearts/plot) while lowest (2.21 dead-hearts/plot) by S. incertulus infestation were noted in chlorantraniliprol + Thiamethoxam plots under AWD irrigation. However, all the tested treatments were found superior over control. Results of white earheads showed that maximum (12.1 white earheads/plot) were recorded in case of control plot followed by Cartap Hydrochloride@ 22 kg/ha (4.16 white earheads/plot), Fipronil @20.0 kg/ha (3.78 white earheads/plot) whereas lowest (2.96 white earheads/plot) were recorded in chlorantraniliprol + Thiamethoxam treated plots. Crop water productivity of paddy plots under AWD irrigation was 0.29 kg/m3 comparatively greater than plots under flood irrigation i.e., 0.12 kg/m3. Use of new granular formulation of insecticide together with improved irrigation can be helpful for Integrated Management of yell stem borer of rice.