Antagonistic effects of some indigenous isolates of Trichoderma spp. against Meloidogyne javanica

Two studies, in vitro and in the green house, were conducted to determine the efficacy of some Saudi Trichoderma isolates against Meloidogyne javanica. The isolates included: Trichoderma hamatum (one isolate), T. viride (one isolate), T. asperellum (three isolates), T. atroviride (one isolate) and T. harzianum (two isolates). In vitro, results showed that all eight tested isolates and their culture filtrates were effective at different levels, in egg hatch inhibition and mortality of juvenile (J2). The mortality of J2 and un-hatching of eggs increased as the concentrations of the culture filtrates increased. In general, T. harzianum (isolate No.27), T. hamatum (isolate No.5) and T. viride (isolate No.8) were the most effective among all tested isolates. Therefore, these three isolates were further evaluated in the greenhouse test on tomato against M. javanica. The three tested isolates inhibited the reproduction, root galling and number of juveniles of M. javanica. The T. harzianum (isolate No.27) was the most effective isolate.