Cost Effective Management of Leafhopper Amrasca Biguttula Biguttula (Ishida) Infesting Okra in Southern Punjab (Pakistan)

Leafhopper is a sap cell sucker of the okra plant. It damages the plants by inserting toxic materials in the leaves, as a result crop showed symptoms of discoloration of leaves and stunted growth of plants which result in yield losses. There was sufficient need for determining the action threshold level to avoid blind chemical sprays for the management of leafhopper. The present study examined the effect of different levels of leafhopper (Amrasca biguttula biguttula) infestation on okra (Abelmoschus esculentus L) yield to identify the economic threshold for leafhopper populations and the most appropriate timing of insecticide application. Field trials were conducted in Multan, Pakistan in 2010 and 2012 and in Bahawalpur, Pakistan in 2012. Crops were sprayed with imidacloprid when the mean population of leafhopper nymphs and adults reached 1-1.5, 1.5-2.5 and 2.5-3.5 per leaf. The total number of sprays required at different population thresholds varied between 2 and 5 sprays on per treatment plot. Based on the cost of spraying and increased net return due to reduced leafhopper damage, spraying crops when the infestation was 1-1.5 leafhoppers/leaf was found to be the most cost effective, giving the highest net returns compared with the untreated controls.