Effect of yard waste compost on plant-parasitic nematode densities in vegetable crops.

The effects of yard-waste compost on densities of plant-parasitic nematodes were determined on four crops at two sites in north Florida. Separate experiments were conducted with sweet corn (Zea mays), cowpea (Vigna unguiculata), yellow squash (Cucurbita pepo), and okra (Hibiscus esculentus). In each test, the design was a randomized complete block replicated four times and involving three treatments: 269 mt/ha yard-waste compost applied to the soil surface as a mulch, 269 mt/ha compost incorporated into the soil, and an unamended control. Final population densities of Criconemella spp. and Meloidogyne incognita were lower in plots receiving a compost treatment than in unamended control plots in only one of eight tests (P </= 0.05). Final densities of Paratrichodorus minor, Pratylenchus spp., and Xiphinema spp. were unaffected by compost treatment in all tests (P > 0.10). Vegetable yields were either unaffected by treatment or, in some tests, were lowest following the mulch treatment (P </= 0.10). Results indicate that the yard-waste compost used had little effect on densities of plant-parasitic nematodes associated with short-term (ca. 4 months) vegetable crops.