Life table characteristics of Macrolophus caliginosus preying upon Tetranychus urticae

The life table characteristics of the polyphagous mirid Macrolophus caligin osus Wagner (Heteroptera: Miridae) preying on various stages of Tetranychus urticae Koch (Acari: Tetranychidae) with tomato as host plant were describ ed at 22 degrees C. The following average parameters were obtained: Female longevity: 28.7 days; fecundity: 0.7 eggs/female/day; egg mortality: 2.6%; pre-oviposition period: 5.5 days; oviposition period: 18.1 days; post-ovipo sition period: 3.2 days; juvenile development time: 26.8 days; juvenile mor tality: 34.9%; and sex ratio (female/(female+male)): 0.46. Life table param eters were estimated as net reproduction rate (R-0): 6.15; intrinsic rate o f increase (r(m)): 0.031 day(-1); finite rate of increase (lambda): 1.032; mean generation time (T-c): 58.17 days; and doubling time (T-2) 22.2 days. The parameters obtained were in accordance with those reported for M. calig inosus fed on another mite species (T. turkestani Ugarov & Nikolski (Acari: Tetranychidae)). However, compared to the performance of M. caliginosus fe d on common glasshouse insect pests, a diet consisting of only mites appear ed to be inferior. However, being a voracious predator, M. caliginosus may be a valuable addition to existing methods of mite control.