LAUSR

The southern root-knot nematode (Meloidogyne incognita) is one of the most devastating threats to cucumber production in China. The ban of methyl bromide and restricted use of other fumigants and high-toxicity of non-fumigant nematicides increases the need for more selective non-fumigant nematicides that pose fewer risks to the environment to manage M. incognita. Fluopimomide is a new fungicide with a similar chemical structure to fluopyram, a fungicide possessing nematicidal activity. However, the efficacy of fluopimomide against M. incognita and its effects on cucumber yield have not been evaluated. In this study, we examined the nematicidal effect of fluopimomide on M. incognita under laboratory and field conditions. In the laboratory, fluopimomide was highly toxic to second-stage juveniles (J2s) and eggs of M. incognita with a median lethal concentration (LC50) of 8.1 and 11.6 mg L−1, respectively, after 24 h exposure. In field trials, fluopimomide applied at 250, 500 and 750 g ha−1 was effective in reducing population densities of M. incognita J2s and root galling caused by the nematode, meanwhile, enhancing plant height in two consecutive years (2017–2018). Furthermore, fluopimomide at 750 g ha−1 significantly increased fruit yield of cucumber compared to abamectin and fosthiazate, the most widely used non-fumigant nematicides to manage M. incognita in China. Overall, soil application of fluopimomide was effective in management of M. incognita in cucumber production, while enhancing cucumber fruit yield.