Integrated Management of Chive Gnats ( Yang & Zhang) in Chives Using Entomopathogenic Nematodes and Low-Toxicity Insecticides.

is a major pest that causes damage to chive production, and which has developed resistance to highly toxic chemical insecticides. Entomopathogenic nematodes (EPN) show a high potential for control. This study aimed to develop an effective management method against larvae, using EPN with low-toxicity insecticides. Fourteen selected insecticides had no significant effects on the survival and infectivity of SN and LN2. Synergistic interactions were observed for imidacloprid and osthole with SN against larvae. SN was more effective than LN2 against at 15 and 20 °C, and the addition of imidacloprid at 1/10 recommended concentration (RC) significantly increased the efficacy of SN. The year-round occurrence of the larvae in chive fields treated by EPN and imidacloprid at 1/10 RC was studied. Results showed that the application of EPN with imidacloprid at 1/10 RC successfully suppressed larval populations of in chive fields, thus significantly increasing the yield of chive. The practical method of applying EPN-imidacloprid combinations provided a cost-effective and environmental safety strategy for controlling larvae in chive production, which can reduce the usage of toxic chemical insecticides.