Population dynamics of defoliating insect pests of mango in the coastal agroecosystem of Tamil Nadu

Abstract

Population dynamics of defoliating insect pests of mango was studied in the coastal agroecosystem of Tamil Nadu. Seven species of defoliating insect pests were recorded and among them, leaf webber, Orthaga exvinacea (Hamp.), leaf caterpillar, Bombotelia jacosatrix (Guen), shoot borer, Chlumetia transversa (Walk.) and leaf twisting weevil, Apoderus tranquebaricus (Fab.) were recorded with considerable leaf damage. The peak incidence of above pests viz., leaf webber (3rd week of September), leaf caterpillar (2nd and 3rd week of December), shoot borer (3rd and 4th week of December) and leaf twisting weevil (3rd week of August). Incidence of leaf webber and leaf twisting weevil was positively correlated with maximum and minimum temperature whereas leaf caterpillar and shoot borer were negatively correlated. Rainfall and relative humidity had positively influenced all the selected pests whereas wind velocity showed negatively impact.