Sucking pests of sunflower with special reference to thrips palmi karny its relation with necrosis virus and management

Abstract

Investigation on sucking pests of sunflower with special reference to Thrips palmi newlinekarny, its relation with necrosis virus and management was carried out at RARS, Raichur, newlineKarnataka, India during 2005-07. The seasonal incidence studies indicated the prevalence of newlinehigh population of leafhoppers in the Rabi, thrips in kharif and higher incidence of necrosis newlinevirus in kharif. Studies on leafhoppers indicated significant and negative correlation with newlinemaximum temperature, minimum temperature and wind. Thrips were significantly and newlinepositively correlated with maximum temperature. Necrosis virus incidence indicated newlinesignificant and positive correlation with minimum temperature, rainfall, morning and evening newlinerelative humidity, wind speed and cloud coverage. The relationship between thrips and newlinenecrosis virus was positive. newlineLeafhopper and whitefly were not involved in transmission of necrosis virus. newlineWhereas, T.palmi was able to acquire and transmit the virus. Out of 36 weed hosts observed newlinefor necrosis 13 were found positive to DAC-ELISA test. newlineThe management of sucking pests and necrosis studies revealed that, the treatment newlinecomprising of RDF (100%) + RPP was superior followed by treatment with vermicompost (2.5 newlinet ha-1) + RDF (50%) + GCK (1%) + vermiwash for leafhoppers, thrips and necrosis disease newlinewith higher yields. In another experiment, Treatment comprising of oxydemeton methyl at 1.5 newlineml/l spray recorded lowest thrips population and lesser necrosis followed by treatment with newlinesorghum leaf extract (10%) + imidacloprid 17.8 SL at 0.25 ml/ l spray. newlineModule-I comprising of growing sorghum along border (four rows) sown before 15 newlinedays of main crop followed by seed treatment with imidacloprid 70 WS at 5 g/ kg of seed and newlineapplication of vermicompost (2.5 t ha-1) + 50% RDF and application of two sprays of neem newlineformulation was best IPM module in managing sucking pests and necrosis virus disease. newline