Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 5, 1997
Publication Date: N/A
Interpretive Summary: Only a few nematicides are registered for nematode control on minor crops. Nonchemical methods are needed to manage nematodes on vegetable crops. The effectiveness of fallow, bermudagrass sod rotations, and a nematicide on nematode control in okra, snapbean, and pepper was determined in a 3-year study. Root-knot nematodes caused more damage on roots of okra than on snapbean and pepper. The application of a nematicide (fenamiphos) reduced root damage on okra following fallow and 1-year sod during the first year of the study, but not thereafter. A few galls were observed on roots of snapbean following 2- and 3-year fallow but none following 1-, 2-, and 3-year bermudagrass sod. No galls were observed on roots of pepper in any treatment. In the final year of the study, yields of all crops were greater following 3-year sod than fallow. Fallow and 3-year sod-based rotations proved beneficial in managing root-knot nematodes on these minor crops.
Technical Abstract: The efficacy of fallow, Coastal bermudagrass sod-base rotations, and fenamiphos for control of root-knot nematode (Meloidogyne incognita race 1) and soilborne fungi in okra (Hibiscus esculentus cv. Clemson Spineless), snapbean (Phaseolus vulgaris cv. NemaSnap), and pepper (Capsicum annuum cv. Charleston Hot) was evaluated in field tests from 1993 to 1995. Numbers of fM. incognita in the soil and root-gall indices were greater on okra than snapbean and pepper. The application of fenamiphos at 6.7 kg a.i./ha did not reduce (P=0.05) numbers of M. incognita in the soil on any sampling date when compared with untreated plots. The application of fenamiphos reduced root-gall indices of okra following fallow and 1-year sod in 1993, but not thereafter. A few galls were observed on roots of snapbean following 2- and 3-year fallow but none following 1-, 2-, and 3-year bermudagrass sod. Pepper roots were not galled by M. incognita in any plots. Population densities of Pythium spp. and Rhizoctonia solani AG-4 i soil after planting vegetables were reduced by 2- and 3-year sod compared with fallow, but were not affected by fenamiphos. Yields of snapbean, pepper, and okra were not different (P=0.05) between fallow and 1-year sod. Yields of all crops were greater following 3-year sod than fallow. The application of fenamiphos prior to planting each crop following fallow or sod did not affect (P=0.05) yields.