Inhibitive effects of Candida guiliermondii on pine wilt disease caused by Bursaphelenchus xylophilus
季也蒙假丝酵母对松材线虫病的抑制作用

Pine wilt disease caused by pine wood nematodes,Bursaphelenchus xylophilus,isone of main forest disease.It was reported that pathogenic microbes accompanying pine wood nematodes and microbial endophytes of pine tree were involved in this disease.A primarily study on inhibitive effects of strain C,isolated from cultured pine wood nematodes,on pine wilt disease was carried out in the laboratory.Aquacultural exercised twigs of Pinus massoniana were inoculated with pine wood nematodes,strain C,and the mixture of the two former,respectively.The results showed that both relative transpiration intensity and relative weight of twigs inoculated with nematodes were the least,then those of twigs inoculated with the mixture and those of twigs inoculated with strain C.Fifteen days after treatment,relative weight of twigs inoculated with nematodes was significantly less than that of twigs inoculated with strain C(p<0.05).Survival days of twigs inoculated with nematodes was significantly less than that of the others(p<0.05).Number of twigs with brown stain leaves of pine twigs inoculated with nematodes was significantly more than that of twigs inoculated with strain C(p<0.05).There was no significant difference between numbers of nematodes separated from twigs inoculated with nematodes and twigs inoculated with the mixture.8-monthold seedlings of P.massoniana without roots were cultural exercised in filtrate of Czaper's medium of strain C and both their infected rate and disease index were significantly less than those in control treatment in 6 days later(p<0.05).These showed that strain C had inhibitive effects on this disease and some metabolites from strain C was in favor of antidisease and survival of pine seedlings.It was suggested that strain C inhibited pathogenic microbes accompanying nematodes and microbial endophytes of pine tree,or improved vitality and anti-adversity ability of pine tree.Strain C was identified as a strain of microzyme,Candida guiliermondii,by being observed under electron microscope and referring to API 20 C AUX identification system.