Influence of different nitrogen levels on the management of Bt cotton sucking pests

Abstract

An experiment was conducted in order to manage different sucking pests in plots under different increasing nitrogen doses 0, 120, 150, 180, 225, 280, 350, 440 kg ha-1 in Jaadu BG-II cotton hybrid plants. The sucking pest incidence was low till 38 DAS and from thereafter the leafhopper population crossed ETL at 48 DAS i.e. 6.73 to 17.83 leafhoppers per three leaves ¬-and at 97 DAS aphids i.e. 32.93 to 160 aphids per three leaves and leafhopper population i.e. 3.9 to 8.6 leafhoppers per three leaves, crossed ETL from 0 to 440 kg N ha-1 ¬respectively. The plot was sprayed with fipronil 5% SC @ 50 g a.i. ha-1 at 48 DAS and second with acephate 75% SP @ 750 g a.i. ha-1 at 97 DAS.