Control Efficacy of Nematicides against Ectoparasitic Nematodes in Zoysiagrass on Golf Courses

Various plant parasites cause damage to turfgrass, and various parasitic nematodes also cause damage to zoysiagrass, particularly the ectoparasitic nematodes. Turfgrass damage caused by various ectoparasitic nematodes is prevalent on golf courses, and nematode management is urgently needed, but information on practical nematicides is scarce. Therefore, this study compared the control efficacy of novel nematicides (Imicyafos, Fluopyram, and Cyclobutrifluram) against ectoparasitic nematodes that are problematic in zoysiagrass, based on formulation and soil depth. The control efficacy of nematicides on golf course turfgrass, which exhibited differences in nematode species composition and density, varied depending on nematode group, formulation, and soil depth. Granular nematicides were relatively effective in test sites receiving high precipitation after treatment, and control efficacy was higher at depths of 0-5 cm near the soil surface than at depths of 5-10 cm. It is believed that the type and formulation of nematicides should be considered taking into account the soil distribution characteristics of the dominant nematodes in the control target area.