This study evaluated the nematicidal activity of the cell-free crude extract (CFCE) of Pleurotus djamor on Meloidogyne incognita under greenhouse conditions. The fungus was grown in a solid medium for 14 days in the dark. Distilled water was added to the medium, filtered, and centrifuged, and the proteolytic activity of the CFCE produced was measured. Three experimental groups were established: control group (distilled water), CFCE (denatured enzymes), and CFCE (active enzymes). The nematicidal activity of the extracts was assessed in vitro on second-stage juveniles (J2) and eggs of M. incognita, separately. Under greenhouse conditions, CFCEs were applied to tomato seedlings grown on substrate infested with M. incognita eggs. About the in vitro tests, the active CFCE showed a significant difference concerning the control group (p<0.05) according to the t-test, with a 22% reduction in eggs. On the other hand, about J2, both treatments showed a significant difference compared to the control (p<0.01) with a 100% reduction, but no significant difference between themselves (p>0.05). Similarly, the treatments in the greenhouse showed the same statistical behavior as the control (p<0.01). However, there was no significant difference between them (p>0.05) regarding the number of eggs and the number of galls. The reduction in the number of eggs was 94 and 97 % and in the number of galls was 71 and 67% for denatured and active CFCE, respectively. This study points to the nematicidal action of metabolites on J2 and the activity of enzymes on M. incognita eggs.
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