Predatory mites, a green pesticide, and an entomopathogenic compound: A proposed IPM tactic based on pest species diversity indices and population dynamics

This study was aimed to investigate the population dynamics and diversity indices of three invasive species; the two-spotted spider mite (TSSM) Tetranychus urticae Koch (Acari: Tetranychidae), the silver leaf whitefly Bemisia tabaci Genn. (Hemiptera: Aleyrodidae), and the onion thrips Thrips tabaci Lindman (Thysanoptera: Thripidae) on four tested plants; Siberian (Russian) kale Brassica napus var. pabularia L., Italian (Tuscan) kale Brassica oleracea var. palmifolia L. (Brassicaceae), spearmint Mentha spicata L. and Saudi Mint Mentha longifolia L. (Lamiaceae); in addition to evaluating a proposed IPM protocol in two experimental sites (Om Saber, Beheira Governorate and Kom Oshim, Fayoum Governorate). The proposed IPM program consisted using predatory mites; Phytoseiulus persimilis Athias-Henriot, Amblyseius swirskii Athias-Henriot, and Cydnoseius negevi (Swirski & Amitai) (Acari: Phytoseiidae), a green pesticide, and an entomopathogenic compound. Samples were collected from tested plants for two seasons to calculate pest population dynamics, and diversity indices, before and after IPM treatments. The resulting data showed statistically significant fluctuation, population dynamics, abundance, distribution, and diversity indices of the three targeted pest species recorded on the four tested plants. The proposed IPM protocol resulted in a significant reduction percentage when A. swirskii was used compared to other tactics. It is discussed that abiotic and biotic factors together help in explaining why various pest species build their communities rapidly and increase their parameters that become above the Economic Injury Level (EIL). Such factors are hypothesized to affect the plant-arthropod, predator-herbivore, predator-predator, and tri-trophic interactions. The proposed protocol recommends the consideration of application timing and merging tactics together to get maximum efficiency.