LIFE-HISTORY AND LIFE TABLE OF AMBLYSEIUS-BADRYI, AS A SPECIFIC PREDATOR OF ERIOPHYID GRASS MITES (ACARI, PHYTOSEIIDAE, ERIOPHYIDAE)

Studies on the life history and life cable of Amblyseius badryi Yousef & El-Brollosy were carried out in the laboratory by rearing it on the eriophyid gall mite Eriophyes dioscoridis Soliman & Abou-Awad nymphs of the two-spotted spider mite, Tetranychus urticae Koch, and the citr us brown mite Eutetranychus orientalis (Klein). It was the dominant ph ytoseiid mite on grasses or on fallen leaves under fruit trees. Indivi duals of A. badryi did nor feed on several acarine prey. Nymphs of tet ranychid mites were insufficient to induce reproduction. Results may s uggested that the predator is a specific predator of eriophyid grass m ites. Development of A. badryi was Faster on eriophyid than an tetrany chid mites. The life cycle from egg to adult was 7 days for both sexes and the adult female longevity was 25 days. Adult females consumed a daily average of 56 E, dioscoridis and laid 1.6 eggs per day. Males sh owed a high reproductive ability for more than 12 days and were able t o mace more than once in excess of females, with maximum of nine times . Population of A, badryi multiplied 18.51 rimes in a generation time of 17.17 days. The finite rare of increase ((c)rm) was 1.19 times/fema le/day.