Bioefficacy of ethiprole + pymetrozine against the white-backed planthopper Sogatella furcifera (Howard), in rice (ADT – 46)

Abstract

The nymphs and adults of white-backed planthoppers (Sogatella furcifera, Howard) remove plant sap resulting in yield loss. Indiscriminate use of insecticides, results in the development of resistance by insects and ill effects on the environment opening the new era of chemicals with novel modes of action with good bioefficacy, higher selectivity, low mammalian toxicity and safety to the environment. Therefore, the introduction of newer insecticide molecules with alternate modes of action will play a serious role in pest management programs. Hence, an experiment was conducted to evaluate the bioefficacy of ethiprole + pymetrozine against white-backed planthopper of rice (ADT – 46) under laboratory and field conditions at Annamalai University, Chidambaram during 2018-20. Ethiprole + pymetrozine @ (T1 - 36.91 + 138), (T2 - 40.13 + 150) and (T3 - 45.47 + 170) g a.i ha-1 with standard checks T4 - pymetrozine @ (150) g a.i ha-1, T5 - buprofezin @ (200) g a.i ha-1 and T6 - ethiprole + imidacloprid @ (50 + 50) g a.i ha-1 were evaluated against white-backed planthopper. The standard checks were of positive control i.e., reference insecticides which is in common use The results revealed that T3 recorded the lowest population of white-backed planthopper/hill at 15 day after spraying (1.13 hoppers/hill in August – December 2018 and 1.79 hoppers/hill in August – December 2019 respectively) giving better yield. The population of natural enemies was comparatively lower in all insecticidal treatments than in the control.