Quality control of the predatory mite Euseius scutalis (Acari: Phytoseiidae) against Tetranychus turkestani (Acari: Tetranychidae) over 30 generations of rearing on cattail pollen

Abstract

In this study life table parameters and predation activity of E. scutalis on a diet of T. turkestani were studied before the supply of Typha pollen (G0) and, after 10 (G10), 20 (G20), and 30 (G30) generations of being reared on cattail pollen (Typha latifolia L.). Our results showed that the longer the rearing of E. scutalis on cattail pollen before switching to T. turkestani, the most impact it had on the developmental duration of the predatory mite. The female adult longevity was the highest in G0. In the older generations (G20 and G30), adult pre-oviposition period (APOP) was shorter than in younger generations (G10). The adult females of G0 had the longest oviposition days. The intrinsic rate of increase (r) and finite rate of increase (λ) of E. scutalis were highest in G20. There was no significant difference in the parameters R<sub>0</sub>, r, λ, and T (mean generation time) before and after thirty generations of rearing on cattail pollen when exposed to T. turkestani. The proportion of male progeny produced by this predator was higher than that of females during both the early and late ages of the oviposition period. The predation rate of E. scutalis was not affected by the time of rearing on cattail pollen before switching to T. turkestani. Euseius scutalis consumed an average of 435.93 T. turkestani over its lifetime before the predator was reared on cattail pollen. This predation rate did not differ significantly after ten and thirty generations passed on a diet of Typha pollen. Overall, the findings of the current study indicated that E. scutalis long-term reared on cattail pollen could be a good candidate as a profitable predator on plants infested with T. turkestani.