Abstract
Laboratory experiments were carried out to investigate the effect of different diets on the biology of the phytoseiid mite, Typhlodromus negevi (Swirski and Amitai). The predatory mite developed and reproduced better when fed on the eriophyid mite, Aceria dioscoridis (Soliman and Abou-Awad) than on pollen grains of both date palm (Phoenix dactylifera L.) and corn (Zea mays). Total egg production was highest when the predator was fed on A. dioscoridis recording 41.27 eggs/female and lowest on both pollen of corn and date palm (29.53 and 9.00 eggs/female), respectively. Female longevity was the longest (61.47 days) when fed on the motile stages of A. dioscoridis, followed by pollen of corn and date palm (36.47 and 31.33 days), respectively. The predator recorded the highest intrinsic rate of increase (r(m)= 0.22 & 0.20 females/female/day) when fed on pollen of corn and motile stages of A. dioscoridis, respectively, followed by pollen of date palm (0.16 females/female/day). The findings indicate the potential of pollen for use as a supplemental food source to maintain the population of the generalist phytoseiid mite, T. negevi in the periods when prey is scarce or absent.