Abstract
The use of nematodes as biological control agents of insect pests in Korea has a short history with concentrated efforts being made since 1986. The major focus of the research has been on the obligate parasitic nematodes in the families Mermithidae, Steinernematidae, and Heterorhabditidae. Research with Agamermis unka, a naturally-occurring mermithid parasite of the brown planthopper Nilaparvata lugens in rice, has shown that it is the most important biological control agent of this insect in Korea. In some years, this mermithid will suppress the brown planthopper effectively, especially when this insect population is low. In other years when the brown planthopper populations are extremely high, chemical pesticides are required for insect suppression. The mermithid is compatible with some chemical pesticides, and through proper rice management practices, it may be conserved and work in concert with pesticides to effect integrated control of the brown planthopper. Research with the steinernematid and heterorhabditid nematodes has shown that they also occur naturally in soils throughout the country. Because these nematodes have a wide host range, they have been tested against several Korean vegetable, rice, turfgrass, and forest insects. Current research emphasis has been to increase the efficacy of these nematodes against turfgrass insects. Although the steinernematids and heterorhabditids are not commercially available in Korea, the promising results against a number of insect pests may spur private industry to pursue their development in the near future.
