Stem application of neonicotinoids to suppress Coccus viridis (Green) population in coffee plantations.

摘要

Two field trials were carried out during August 2002 and March 2003 at 2 locations in Yercaud, Tamil Nadu, India, to assess the efficacy of application of neonicotinoids on the auxillary branches (first experiment) and main stem (second experiment) of coffee (Coffea arabica) plants against Coccus viridis. The treatments comprised thiamethoxam 25 WG at 0.025 and 0.050 g/plant, imidacloprid 17.8 SL at 0.025 g/plant, imidacloprid 80 SL at 0.050 g/plant, dimethoate 30 EC at 0.300 g/plant, and an untreated control. In both trials, imidacloprid and dimethoate were included as the standard controls. The application of thiamethoxam at 0.05 g/plant on the auxillary branches was very effective in suppressing the population of Coccus viridis, causing 93.1% reduction. The application of insecticides on the main stem was less effective. Thiamethoxam at 0.025 g/plant was comparable with imidacloprid (0.050 g/plant) and dimethoate (0.300 g/plant)..