Effect of the fungus Paecilomyces lilacinus on the larval population and root knot formation of Meloidogyne incognita in tomato

Abstract

Two experiments were conducted in the greenhouse to determine the effect of the fungus Paecilomyces lilacinus in controlling the larvae and root knot or root gall formation of Meloidogyne incognita in tomato cultivar Floradel. The plants were inoculated with the fungus alone, the nematode alone or both simultaneously at different time intervals and combinations. Observations made 60 days after the inoculations showed that the fungus controlled the nematodes and reduced root knot formation. In the first experiment, significantly fewer larvae were found in roots and soil of plants inoculated with the fungus 3 days previous to nematode inoculation. A higher root knot index in plants inoculated with nematodes alone; with fungus and nematodes simultaneously; and with the fungus alone 3 days after nematode inoculation was also obtained. In the second experiment, a tendency for a reduced number of nematodes in soil and roots and low gall indices was observed as the time of inoculation of the fungus before the nematode inoculation was increased. Plants inoculated with the fungus 4 and 6 days before nematode inoculation had significantly lower gall indices than the other plants inoculated with the nematode, the fungus, or both.