Research into new nematicides that provide adequate control against root-knot nematodes in a more environment-friendly way is of great interest to vegetable growers. Thus, the effect of fluopyram, a relatively new chemical nematicide, was evaluated against a Swiss population of Meloidogyne incognita in vitro, in soil and as a planting hole treatment for tomato, lettuce and cucumber plants. Fluopyram treatment in vitro revealed LC50 (lethal concentration, 50%) ranging from 2.15–0.04 µmol of fluopyram/L after 1–14 days of exposure. However, some nematodes (visually categorized as dead) were able to recover and infect cucumber plants. Fluopyram’s optimal application time appeared to be up to 1 day after planting, with a significant control effect on M. incognita up to 14 days after planting. A root penetration assay showed that only nematodes that remained in the rhizosphere were controlled by fluopyram. Furthermore, fluopyram planting hole treatments on lettuce, tomato and cucumber plants, successfully controlled M. incognita in the root zone under greenhouse conditions. Overall, this study contributes to an optimized application of fluopyram for the control of M. incognita in vegetable crops, highlighting its effectiveness in soil and showing its limitation to control juveniles that have already invaded the root systems of plants.
