Reduction of phytoparasitic nematodes on tomato by soil solarization and genotype.

The effects of soil solarization and tomato (Lycopersicon esculentum) genotype on populations of plant-parasitic nematodes and bacterial wilt were examined in North Florida. Maximum soil temperatures achieved under solarization treatments using a photoselective polyethylene mulch were 49.5, 46, and 40.5 C at depths of 5, 15, and 25 cm, respectively. Soil solarization reduced (P < 0.05) populations of Paratrichodorus minor, Rotylenchulus reniformis, and Criconemella spp. 85 days after transplanting on the cultivar Solar Set. Soil solarization reduced (P < 0.10) populations of P. minor, R. reniformis, and Criconemella spp. on the breeding line Fla. 7421. Reductions of P. minor and Criconemella spp. on Solar Set and Fla. 7421 were similar to those achieved by fumigation with a 67:33 mixture of methyl bromide and chloropicrin (448 kg/ha). Fla. 7421 reduced (P < 0.10) populations of R. reniformis compared with Solar Set. Neither soil solarization nor fumigation reduced the incidence of bacterial wilt on the susceptible cultivar Solar Set. This study demonstrates the ability of soil solarization to provide season-long control of plant-parasitic nematodes of tomato under a climatic regime characterized by periods of abundant rainfall and extended cloud cover.