Yield Benefits of Nematicide Applications across Multiple Cotton Cultivars in Root-Knot and Reniform Nematode Infested Fields

In 2018, an estimated 204,700 bales of the total cotton crop in the United States was lost due to the reniform nematode (Rotylenchulus reniformis), and an estimated 485,300 bales of cotton were lost to the root-knot nematode (Meloidogyne spp.).  With large losses reported to both reniform and root-knot nematodes in cotton year after year, two studies were conducted in order to investigate yield losses to reniform and root-knot nematodes over multiple cotton cultivars currently available on the market during the 2019 growing season.  In the root-knot nematode infested field, AgLogic 15G (Aldicarb) was evaluated as an in-furrow granular application at planting.  In the reniform nematode infested field, Copeo Prime (Fluopyram) and NemaStrike (Tioxazafen) were evaluated as seed treatments.  Plant parameters analyzed for both trials included plant stand, plant height, shoot fresh weight, root fresh weight, and nematode eggs per gram of root.  In the root-knot nematode trial, AgLogic 15G significantly reduced average eggs per gram of root across all varieties by 90% (398 eggs/g root to 38 eggs/g root).  In the reniform nematode trial, Copeo Prime significantly reduced eggs per gram of root by 79% (6782 eggs/g root to 1372 eggs/g root), and NemaStrike eggs per gram of root were 35% higher compared to the untreated plots (6782 to 9195 eggs/g root).  Cotton yields are currently being harvested, and will be available in the near future.  Overall, 2019 was a favorable year for both root-knot and reniform nematodes to develop and significantly impact cotton production in Alabama.