Life table and biological characteristics of Macrolophus pygmaeus when feeding on Myzus persicae and Trialeurodes vaporariorum

The life table and biological characteristics of the predatory bug Macrolophus pygmaeus Rambur (Hemiptera: Miridae) were studied when the bugs were fed with Myzus persicae (Sulzer) (Homoptera: Aphididae) feeding on eggplant and with Trialeurodes vaporariorum Westwood (Homoptera: Aleyrodidae) feeding on tomato plants. The tests were done at five temperatures between 15 and 30 degreesC, using a L16:D8 photoperiod and 65 +/- 5% r.h. Most eggs (range 85 to 90%) hatched at 15 and 20 degreesC. Incubation period was shortest at 27.5 degreesC (8.45 and 8.38 days on eggplant and tomato, respectively). Preoviposition was also shortest at 27.5 degreesC (5.10 and 4.75 days on eggplant and tomato, respectively) whereas fecundity was highest at 20 degreesC (213.90 and 228.25 eggs on eggplant and tomato, respectively). Maximum longevity of females was at 15 degreesC (122.40 and 129.35 days on eggplant and tomato, respectively). Mean generation time was longest at 15 degreesC on both host plants (122.75 and 124.64 days, respectively). The intrinsic rate of increase of M. pygmaeus was highest at 27.5 degreesC with similar values on eggplant (0.0981 day(-)1) and tomato (0.1040 day(-)1). Doubling time was shortest at 27.5 degreesC (7.06 and 6.67 days on eggplant and tomato, respectively) and, also, finite rate of increase was highest at 27.5 degreesC (1.1031 and 1.1096 on eggplant and tomato, respectively). The results show that the predator M. pygmaeus develops well on the aphid M. persicae or on the whitefly T. vaporariorum, both of which are important pests of vegetable crops. This predator is also well adapted to the temperatures that occur both in greenhouses and in the open field in the Mediterranean region. Compared to other natural enemies of whiteflies, such as Encarsia formosa Gahan (Hymenoptera: Aphelinidae), Macrolophus pygmaeus can increase at relatively low temperatures.