The effect of soil solarization and fertilization was evaluated for nematode control in 'Veronica' lettuce in naturally infested soil. The two greenhouse experiments consisted of five fertilization treatments: organic fertilization; ammoniacal nitrogen (ammonium sulphate); NPK fertilization; organic and NPK fertilization; control (without fertilization), in solarized and non-solarized soils. In the solarized plot the soil was covered during 132 days with transparent plastic film. The nematode populations were evaluated in two layers (010 cm and 10-20 cm) with soil collections done at three times (before solarization; after solarization; and after harvest). The experimental design was of sub-subdivided blocks plots with assessments in space and time (5 fertilization x 2 depths x 3 times). The effect of solarization on nematode control was dependent on fertilization and soil depth. Solarization reduced nematodes population at 0-10 cm depth in all the fertilization treatments. Solarization associated to ammoniacal nitrogen reduced nematode diversity at 10-20 cm depth. Solarization associated to organic, ammoniacal nitrogen, NPK and organic + NPK fertilization reduced efficiently gall numbers, egg masses number and phytoparasitic nematodes, specially Meloidogyne spp., in lettuce roots. Solarization associated to organic fertilization has a potential to be used in nematode control and to reduce pesticides application.
Lactuca sativa L; Meloidogyne sp.; solar energy; soil thermal treatment
