Optimum spray volume requirements for rice at different stages of growth

Abstract

Field experiments were conducted for two seasons in 1980-'81 at the College of Agriculture, Vellayani for assessing the optimum volumes of insecticide suspension required for treating rice crop at different growth stages of the crop using a pneumatic knapsack sprayer and mist blower. The results showed that the optimum volumesof 0.2",, carbaryl suspension required to give highest deposits on leaves were 200, 300, 500 and 500 I/ha in the case of a pneumatic knapsack sprayer and 90, 1 20, 1 80 and 1 80 I/ha in the case of a mist blower at 30, 45, 60 and 75 days after sowing respectively. The optimum volumes thus obtained were correlated with the leaf area indices of the respective stages of growth and relevant statistical models were fitted for both the type of sprayers.