| Investigation showed that the nematophagous fungi in Fujian province were very rich in resource and abundant in biodiversity. In this study, 868 isolates of nematophagous fungi were obtained from samples of the root-knot nematode collected from 17 plants. 17 species and 3 varieties of 24 genera were identified among the isolates. Ascochyta sp., Chalaropsis sp., Cylindrocladium sp., Papulospora sp., Pleiochueta sp., Pleurophagmmm sp., Tolura sp.. Scopulariopsis sp., Fusarium helersporium, Fusarium semitectum, Cunninghamella elegans were first time reported for the root-knot namatode. And F. oxysporium, F. solani, Paecilomyces lilacinus, Verlicillium chlamydosporium were the dominant populations in the nematophagous fungi on root-knot nematode in Fujian. The frequency of their appearance was 64.7%, 82.3%, 52.9% and 52.9% respectively on the 17 plants, taking up 22.78%, 17.61%, 19.45% and 9.78% of all the isolates in this study. The fungi mainly parasitized eggs of root-knot nematode. They could be found both on eggs (66.7%) and female nematodes (24.3%).In Fujian. the flora of nematophagous fungi on root-knot nematode was diverse. The relationship between species, quantity, dominant population of nematophagous fungi and root-knot nematodes, their host plants was close.P. lilacinus and V. chlamydosporium were important nematophagous fungi. But their pathogenicity to root-knot nematode varied from one population to another. In this pathogenicity analysis, result showed that the parasitic ratios of the fungi (V. chlamydosporium var. chlamydosporium and V. chlamydosporium var. catenulalum) on eggs were 29.9% and 24.7% in the petri-dish test. Their control effect on root-knot nematode disease reached 25.9% and 40.8% when tested in pot experiment. For P. lilacinus, parasitic ratio was 11.7%~39.5%, control effect reached 17.9%-77.8%.Five strains with strong nematicidal activity were obtained in the analysis with the fermentation liquid extract of some isolates.
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