Researches On The Screening Of Nematophagous On Basidiomycetes And Coprinus Comatus Effectivenesson Control Of Root-knot Nematodiasis In Tobacco

The research on nematophagous basidiomycetes began from establishment of Nematoctonus by Drechsler in 1941,the fungi act on nematodes with prey and endoparasite.This thesis made primary studies on the biocontrol effects and biological characteristics of some nematophagous basidiomycetes and Coprinus comatus effects on tobacco knot nematodiasis,in order to provide scientific and theoretical basis of the biological control nematodes,mainly obtained the following results:1,The collected basidiomycetes totaled up to 86 strains,among them 43 strains were acquired to pure culture and were primarily screened,then acquired 10 strains with nematode death rate above 70%on 48h,which contained 2 strains with nematode death rate at 100%on 48h.The studies on function methods of basidiomycetes to nematodes discovered:Their function methods contained hyphae tying,toxin poisoning and parasitizing and decomposing nematodes.2,Study on the relationship between biological characteristics and kill nematode of Coprinus comatus.The effect is indicated that the maximum growth of fungi occurred at temperature 24～28℃,pH6～7 and in the dark of the hyphae of C.comatus.Although media, temperature,light and pH value had some effects on hyphal growth,they did not affect destroy nematodes.When nematodes touched the hyphae within 48 hours,the destroying rates of nematodes treated by the hyphae were above 90%(except WA).3,The result of the pot trial of C.comatus manifested:C.comatus could reduce the root knots occurring on tobacco and promote the growth of tobacco in certain degree,the effect of different strain had a little dissimilarity,The C.comatus with different quantity and application time in the soil had different effect on tobacco knot nematodiasis,the control effects of the 250g/ pot,125g/pot,84g/pot and 42g/pot were 57.51%,50.36%,40.43%and 30.50%respectively; The processing set root of that 1 d,5 d and 20 d of germ of knots of repress result to distinguish to 42.41%,44.17%and 57.51%.4,Using C.comatus the processing carried on tobacco knot nematodiasis to defend an effect of the in the field experiment a research.Expressing as a result that C.comatus have to defend an effect on tobacco knot nematodiasis,distinguishing to 47.55%to tobacco root's prevention and cure result which knot nematode,the control effects of P.ostreatus and avermectins distinguishing to 47.75%,52.88%.In addition,several growths which handle to the tobacco all include to certainly promote a function.5,Nematodes were indentified mainly into eight,furthermore they were distinguished into four trophic groups:bacterivores,fungivores,plant parasites,omnivores/predators,they included one-order plant parasites and seven-order nonplant parasites.The analysis of different treatments to four trophic groups showed that the treatment of C.comatus,P.ostreatus,Avermectins and could decrease the individual density of tobacco knot nematodiasis and Achieve the purpose of root-knot nematode control;P.ostreatus and C.comatus could decrease the individual density of plant parasites,increase the the individual density of saprophytic nematodes.