Chemical Delivery is Critical to Successful Control of Root-knot Nematodes in Squash: A Case Study of Fluazaindolizine

Root-knot nematode (RKN) (Meloidogyne incognita) is a common pest problem on vegetable crops including tomatoes and squash in south Florida that can lead to significant yield loss when not managed properly. Chemical control is often needed in the management of RKN due to lack of effective soil fumigants. The object of this study was to evaluate the efficacy of fluazaindolizine (Recklemel) in control of RKN on squash. Squash (cv. Enterprise) was seeded in beds covered with plastic, in which the soil was inoculated with RKN 1 week before seeding. Treatments were applied twice by drip injection, one immediately after seeding for all treatments and the second at 2 weeks after the first treatment. In addition, the first four plants at the south end of each plot of the treatments with Recklemel were drenched with 50 mL of a solution of the same chemical to the base of each seedling right after emergence. The initial nematode population was high as some seedlings in several plots wilted soon after emergence or grew poorly. Although Recklemel at 23.0 fl oz/A applied at seeding had the best overall performance, there were no significant differences among the treatments when the chemical was applied through the dripline. However, the plants drenched after emergence grew significantly better and showed much lower levels of root infection by RKN compared to those treated with the chemical only through dripline. The results indicated that Reklemel is effective against RKN in squash but the delivery method is key, which can greatly affect its efficacy. Further research will be needed to develop the best delivery systems for this nematicide for improved RKN control in sustainable vegetable production.