Repartition Spatio-temporelle de Macrolophus caliginosus en Culture de Tomate sous Abri (Heteroptera: Miridae)

摘要

The characteristics of the generalist predator Macrolophus caliginosus made it the main actor in the biological control of Trialeurodes vaporariorum in protected tomato crops; but its action on Bemisia tabaci remains unclear. Because B tabaci does not belong to the natural host spectrum of M caliginosus, the feeding foraging behaviour of the predator is questioned when B tabaci is the only prey available. The movements of M caliginosus and its aggregation on B tabaci populations were studied in real conditions of production in two greenhouses equipped with insect-proof nets. Macrolophus caliginosus was first introduced on the crop. Five weeks later, 4 focus (per greenhouse) of B tabaci infestation were generated. In the absence of B tacaci, the M caliginosus population colonized the whole greenhouse and succeeded in maintaining equal larval density for two generations. The density of predator presents on plants infested by B tabaci was significantly higher than the one measured on the other plants. The presence of prey on plants infested with B tabaci probably decreased the intrinsic mortality of predator larvae and enhanced oviposition of adults thereby enhancing their fitness due to feeding.