Seasonal Incidence of Castor Sucking Pests in Southern Telangana Zone, India

Abstract

A study on the population dynamics of sucking pests of castor was conducted at the Indian Institute of Oilseeds Research (IIOR), Rajendranagar, Hyderabad, from November 2023 to March 2024. The sucking pest infestation was started from vegetative stage and continued till harvesting stage. The leafhopper incidence was started in 48th standard meteorological week (SMW) with population of 6.2 leafhoppers/three leaves/plant and reached peak in the 10th SMW with 74.8 leafhoppers/three leaves/ plant. Whitefly infestation was first observed in the 4th SMW with a population of 10.8whiteflies/top leaf/plant, with a peak population of 68.6 whiteflies /top leaf/ plant in the 13th SMW. Thrips infestation was started during the 52nd SMW with a population of 1.2 thrips spike-1, with a peak population of 32 thrips spike-1 in the 8th SMW. All pests showed significant positive correlations with maximum temperature, wind speed, and evaporation and significant negative correlations with morning and evening relative humidity. Specifically, whiteflies were positively correlated with minimum temperature, while leafhoppers and thrips showed no significant correlation with this factor. Leafhoppers and thrips populations were significantly positively correlated with sunshine hours, whereas whiteflies were not. Rainfall had a non-significant negative correlation with all the pest populations.