Development and Reproductive Capacity of the Miyake Spider Mite Eotetranychus kankitus (Acari: Tetranychidae) at Different Temperatures.

Abstract

Simple SummaryEotetranychus kankitus (Acari: Tetranychidae) is an important pest of citrus and occurs mainly in Oriental and Palearctic areas. E. kankitus often coexists with Panonychus citri or Phyllocoptruta oleivora (Acari: Tetranychidae, Eriophyidae), resulting in a pest complex that is extremely difficult to control. As adaptable organisms, insects and mites respond differently to environmental changes, especially to changes in temperature that may occur as a result of climate warming. In this study, E. kankitus was used as a test organism to see how temperature affects development time, survival rate and fecundity. We used the bootstrap-match technique to construct the life-table parameters. The results showed that oviposition was highest at 20–25 °C, while growth rate was highest at 25–30 °C. Although the optimal temperature for growth differs among spider mite species, the species–specific thermal constants could also be used as a potential indicator of the distribution and abundance of arthropods.Eotetranychus kankitus (Acari: Tetranychidae) is an important pest of citrus. Assessing life history parameters is crucial to developing an ecologically sound pest management program. Of the many factors that affect life history parameters of herbivorous insects and mites, temperature has the greatest influence on development rate and reproductive potential. We investigated the effects of temperatures from 15 to 40 °C on the demographic parameters of E. kankitus under a long-day (16:8 (L:D) h) photoperiod. The egg-to-adult development time of E. kankitus decreased as the temperature increased from 15 to 32.5 °C. At 35 °C, the female laid eggs that died at the larval stage. The estimated lower thermal thresholds (t0) were 11.01 and 10.48 °C, and the thermal constants (K) were 190.67 and 188.63 degree-days for egg-to-adult females and egg-to-adult males, respectively. The intrinsic optimal temperatures (TØ) for development were 21.79 and 21.74 °C, respectively. The bootstrap-match technique was used in the construction of the life table paramaters. The net reproductive rate (R0) decreased as temperature increased from 20 to 30 °C, but the lowest rate was observed at 15 °C. The intrinsic rate of natural increase (r) increased from 0.0299 day−1 at 15 °C to 0.1822 day−1 at 30 °C. These findings provide a critical theoretical basis for predicting the occurrence of E. kankitus populations under climate warming and for developing appropriate control strategies.