| Abstract: | Plant residues of broccoli, melon, and tomato with or without addition of chicken manure were used as biofumigants in two pot experiments with Meloidogyne incognita-infested soils. The efficacy of these biofumigants in controlling M. incognita infestation in susceptible tomato bio-assay plants was studied at soil temperatures of 20º, 25º, and 30 ºC. None of the plant residues was effective at 20 ºC, and broccoli was more effective than tomato or melon at 25 ºC. At 30 ºC all three plant residues reduced M. incognita infestation of tomato to very low levels. Chicken manure was effective in one of two experiments at 20 ºC, and at 25 ºC enhanced the efficacy of tomato and melon residue in one of two experiments. At 30 ºC chicken manure was equally effective as the three plant residues but did not further decrease infestation levels in plant residue amended soils. It is concluded that biofumigation to control M. incognita is unlikely to be effective under cool conditions, that at soil temperatures around 25 ºC broccoli is more effective than melon and tomato, and that the addition of chicken manure at this soil temperature may enhance the efficacy. At high soil temperatures, of approximately 30 ºC, the biofumigant source seems of minor importance as strong reductions in tomato infestation by M. incognita were achieved by addition of each of the three plant residues as well as by addition of chicken manure. |
