The effect of strawberry cultivars, infested with Tetranychus urticae (Acari: Tetranychidae), on the olfactory response of the predatory mite Neoseiulus californicus (Acari: Phytoseiidae)

Abstract

Tetranychus urticae Koch (Acari: Tetranychidae) is a key pest of agricultural crop. One of the best candidates for biological control of this mite is Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). In this study, the olfactory response of the predatory mite to seven strawberry cultivars (‘Marak’, ‘Yalova’, ‘Aliso’, ‘Gaviota’, ‘Sequoia’, ‘Camarosa’ and ‘Chandler’) was studied using a Y-tube olfactometer. We used two-day-old female predatory mites that were reared on spider mite-infested strawberry. The behavioral response of the predator was studied in four experiments: 1) clean air vs. uninfected strawberry plant, 2) clean air vs. spider mite-infested strawberry plant, 3) uninfected strawberry plant vs. spider mite-infested strawberry plant and 4) two-cultivar choice test (spider mite-infested). In the first experiment, the attraction of the predatory mite to uninfected strawberry plant volatiles was significant. In the second test, the predators significantly preferred volatiles from strawberry plant infested with T. urticae to clean air. In the third test, 68% to 80% of the predatory mites were attracted to spider mite-infested strawberry plant volatiles compared with uninfected plants. Among the seven strawberry cultivars, the predator responses to volatiles of infested plants varied 62% to 83% and to volatiles of uninfested plant varied 59% to 75%. Herbivore – induced plant volatile emitted from strawberry infested with T. urticae attract the predatory mite. The last test showed that ‘Aliso’ and ‘Chandler’ were more attractive for the predatory mite.