STUDIES ON THE LEAF MINER, LIRIOMYZA TRIFOLII (Burgess) AND ITS PARASITOID Diglyphus isaea (Walker) ON COMMON BEAN PLANTS

This study was conducted during 2009 and 2010 seasons in Giza governorate in order to estimate the population abundanceof major pest Liriomyza trifolii of the common bean plants (Phaseolus vulgaris L.), (Burgess). The percentage of parasitism by Diglyphus isaea (Walker) was also investigated. The population of pest larvae differed during the period of investigation and reached its maximum level on November 28th (62.5 Larvae/20 leaves) and on November 20th (24.8 larvae/20 leaves), during 2009 and 2010 seasons respectively. The percentage of parasitism by Diglyphus isaea (Walker). reached its maximum on November 21st (21.8%) and on November 13th (21.6%) during 2009 and 2010 seasons, respectively. Concerning the overall mean of parasitism by D. isaea on L. trifolii valueswere 9.1 and 11.8%, during 2009 and 2010 seasons, respectively. It can be stated that, this parasitoid plays a natural role for controlling this insect pest.