Evaluation of Neoseiulus barkeri (Acari: Phytoseiidae) for the control of plant parasitic nematodes, Radopholus similis (Tylenchida: Pratylenchidae) and Meloidogyne incognita (Tylenchida: Heteroderidae)

Abstract

ABSTRACTRadopholus similis (Cobb) Thorne (Tylenchida: Pratylenchidae) and Meloidogyne incognita Kofoid and White (Tylenchida: Meloidogynidae) are agriculturally important migratory endoparasitic and sedentary endoparasitic plant nematodes, respectively. In this study, the effects of prey density, starvation time, and temperature on the number of R. similis consumed by a population of Neoseiulus barkeri Hughes (Acari: Phytoseiidae) isolated from the soil were studied in the laboratory. Moreover, the efficiencies of the control of R. similis in the Anthurium andraeanum Linden rhizosphere and of M. incognita in the tomato rhizosphere by mites were tested using potted plant experiments. At prey densities ranging from 100 to 500, the nematode consumption rate increased with the increasing density. With 500 nematodes per arena, the consumption rate of a female N. barkeri starved for 96 h was highest (218 nematodes) at 25°C among starvation treatments, and the maximum consumption rate of a female mite starved for 24 h was 152 nematodes at 28°C in temperature treatments. The addition of N. barkeri reduced the number of R. similis in the rhizosphere of potted anthurium and of M. incognita in the rhizosphere of potted tomato plants. Releasing 400 N. barkeri in the rhizosphere of each pot was optimum for controlling R. similis and M. incognita, and decreased the number of R. similis, root knots, and egg mass by 62.0%, 66.7%, and 69.7%, respectively. Therefore, the use of N. barkeri could be an effective biological method for the control of plant parasitic nematodes.