Effect of age on reproduction and sex ratio of Plodia interpunctella (Hubner) (Lepidoptera: Pyralidae)

The indian meal moth,plodia interpunctella (hubner),is a cosmopolitan grain feeding pest,infesting stored products in the home,grocery stores,warehouses,food processing plants and where food products are stored. studies were conducted to determine the effect of delayed mating on its fecundity,percent egg hatching,survival to adults and sex ratio. all variables were decreased significantly with the increase in age of either sex except sex ratio. however,males continued to produce progeny up to age of 3 days when they were mated with freshly emerged females. no reproduction was occurred when 3 days old virgin females were paired with newly emerged males. there was a male biased sex ratio (54-56% males) in all delayed mating combinations. egg laying was continued up to 8th day when 1-2 days old males and 1 day old females were mated with newly emerged females and males. significantly high fecundity per day was achieved on 2nd,3rd and 4th day after mating in all treatments. copyright 2010 zoological society of pakistan.