Effects of different pollen diets in comparison to a natural prey, Tetranychus turkestani (Acari: Tetranychidae), on development, survival, and reproduction of Euseius scutalis (Acari: Phytoseiidae)

Abstract

The development, survival, and reproduction of the predatory mite Euseius scutalis (Athias-Henriot) (Acari: Phytoseiidae) were studied under laboratory conditions (25 ±1 °C, 65 ± 5% RH, 16:8 (L: D) h) on strawberry spider mite, Tetranychus turkestani Ugarov and Nikolski (Acari: Tetranychidae), and four different pollen including date palm, cattail, golden shower tree and caper bush pollen. Our results showed that E. scutalis mites successfully developed into the adult stage and reproduced on natural prey and plant pollen tested. Diet type significantly affected the developmental time of immature stages of both females and males. Females reared on T. turkestani had a considerably shorter total developmental time than those raised on other diets. Date pollen and spider mites-fed females began laying eggs much earlier than other females. The lower number of laid eggs was recorded for the females raised on golden shower tree, followed by caper bush pollen. The net reproductive rate (R0) of the predators fed golden shower tree was significantly lower than those provided cattail pollen and T. turkestani. Intrinsic and finite rates of increase (r and λ, respectively) were highest in the females fed T. turkestani (0.3300 ± 0.018 and 1.3910 ± 0.0247, respectively) followed by cattail pollen (0.2721 ± 0.0178 and 1.3126 ± 0.0233, respectively). Based on the current findings, it can be concluded that rearing of E. scutalis on the immatures of T. turkestani was considerably better than on other diets with higher values of egg production and population growth rate under laboratory conditions. Furthermore, cattail pollen followed by date palm pollen are suitable alternative diet sources for easy and cost-effective rearing of E. scutalis in the laboratory.