Bio-efficacy and cumulative effect of Verticillium iecanii against Maconellicoccus hirsutus (Green) on custard apple

A laboratory experiment was conducted to evaluate the bio-efficacy and cumulative effect of Verticillium lecanii against Maconellicoccus hirsutus (Green) on custard apple during kharif, 2004. The results revealed that there was a consistent decrease in mortality from first to fourth instars and the crawler’s mortality instars ranged from 26.00 to 82.28 per cent. The early instars of Maconellicoccus hirsutus were the most susceptible than the later instars. The cumulative mortality obtained from all the four instars averaged 95.33 per cent.