Management of Root-knot Nematodes by Phenamiphos Applied through an Irrigation Simulator with Various Amounts of Water.

Phenamiphos (6.7 kg a.i./ha) was applied via an irrigation simulator to squash at planting (AP) and 2 weeks after planting (PP), and to corn AP and 1 week PP to manage root-knot nematodes (Meloidogyne incognita). The nematicide was applied with 0.25, 0.64, 1.27, and 1.91 cm surface water/ ha to a Lakeland sand in which the soil moisture was at or near field capacity. Based on efficacy and crop response, no additional benefits resulted when phenamiphos was applied in volumes of water greater than 0.25 crn/ha. The cost of applying each 0.25 cm of water over a hectare is approximately $1.08, or a 92% reduction in nematicide application cost over conventional methods ($13.50/ha). Low root-gall indices and high yields from squash and corn indicate more effective nematode management when phenamiphos was applied AP rather than PP. Results from this method of applying phenamiphos suggest that certain nematicides could be used as salvage alternatives when nematodes are detected in crops soon after planting. For multiple-pest management, nematicides, other compatible biocides, and fertilizers could be applied simultaneously with sprinkler irrigation.