Behavioral and Biological Effects of Exposure to Tuta absoluta (Lepidoptera: Gelechiidae) Sex Pheromone on Several Trichogramma (Hymenoptera: Trichogrammatidae) Populations

Abstract

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most destructive pests of tomato worldwide. Biological control of the pest using Trichogramma (Hymenoptera: Trichogrammatidae) wasps can be combined with other practices such as use of synthetic sex pheromones for mating disruption or mass trapping programs. In this study, effects of T. absoluta sex pheromone on behavioral responses and fertility life table parameters of Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae), Wolbachia-uninfected (W-) Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae), and Wolbachia-infected (W+) T. brassicae were investigated under laboratory conditions. Female wasps of T. evanescens and T. brassicae (W+) were attracted to the pest synthetic sex pheromone (around 62%) and calling virgin female moths (around 75%) and their responses were affected by the wasp age and temperature. Exposure to the host synthetic sex pheromone significantly reduced the percentage of adult emergence, longevity, and fecundity of female wasps, as well as the time spent to find a mate and duration of mating. However, tested populations were not affected similarly. Despite the laboratory tests, greenhouse experiments showed that the wasps were not caught in the traps baited with T. absoluta synthetic sex pheromone. Complementary studies are needed to precisely determine possible interference between pheromone application and releasing Trichogramma Westwood (Hymenoptera: Trichogrammatidae) wasps to achieve a successful integrated control of T. absoluta.

Lethal and sublethal effects of synthetic and bio-insecticides on Trichogramma brassicae parasitizing Tuta absoluta

“…The integration of Trichogramma spp. with other control measures such as predators, entomopathogens and pheromone traps to control TLM have been considered in the context of Iran, and studies show that these egg parasitoids are extremely important in the IPM programs of TLM [53][54][55]. The wide range of tolerance to environmental changes, the ability for mass rearing, the capacity to kill their hosts before damage occurs and a measurable host preference despite a wide host range are advantages that make Trichogramma spp.…”