Effect of temperature on the development of Tetranychus urticae and Eotetranychus lewisi on strawberry

Abstract

The effect of different temperatures on the development of Tetranychus urticae Koch and Eotetranychus lewisi (McGregor) on strawberry was studied in the laboratory of Department of Entomology, University of California, Davis, USA in 2012. The study results revealed that the immature development of both the mites on strawberry was faster at 20 (6.67 to 7.33 days) and 25 °C (3.33 to 3.67 days) as compared to 15 °C (11.66 to 13.33 days). The total time taken for the development of T. urticae and E. lewisi was found to be decreased with increase in temperature. The maximum fecundity of both the mites was observed at 25 °C. The fecundity of T. urticae (49.15 eggs/female) was found to be more on strawberry as compared to E. lewisi (41.25 eggs/female). Therefore, strawberry was found to be more suitable host for T. urticae. Although, E. lewisi develops faster at lowest temperature (30.00 days) as compared to T. urticae (35.40 days) and successfully completes its life cycle on strawberry at all temperatures. Thus, E. lewisi can become a major pest of strawberry in near future along with T. urticae. Our results showed that temperature is a portentous component that can affect the development and reproduction of both the mites on strawberry.