COASTAL BERMUDAGRASS ROTATION AND FALLOW FOR MANAGEMENT OF NEMATODES AND SOILBORNE FUNGI ON VEGETABLE CROPS

The efficacy of clean fallow, bermudagrass (Cynodon dactylon) as a rot ational crop, and fenamiphos for control of root-knot nematode (Meloid ogyne incognita race 1) and soilborne fungi in okra (Hibiscus esculent us), snapbean (Phaseolus vulgaris), and pepper (Capsicum annuum) produ ction was evaluated in field tests from 1993 to 1995. Numbers of M. in cognita in the sail and root-gall indices were greater on okra than on snapbean or pepper. Application of fenamiphos at 6.7 kg a.i./ha did n ot suppress numbers of nematodes on any sampling date when compared wi th untreated plots. The lack of efficacy could be the result of microb ial degradation of the nematicide. Application of fenamiphos suppresse d root-gall development on okra following fallow and 1-year sod in 199 3, 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 b ermudagrass sod. Population densities of Pythium aphanidermatum, P. my riotylum, and Rhizoctonia solani in soil after planting vegetables wer e suppressed by 2- or 3-year sod compared with fallow but were not aff ected by fenamiphos. Melds of snapbean, pepper, and okra did not diffe r between fallow and 1-year sod. In the final year of the study, yield s of all crops were greater following 3-year sod than following fallow . Application of fenamiphos prior to planting each crop following fall ow or sod did not affect yields.