Study On Using Wood-rotting Fungi To Treat Stumps Of Dead Wood Caused By PWN(Bursaphelenchus Xylophilus)

The pine wilt disease is a kind of worldwide dangerous forest disease.The stumps of the dead wood caused by Bursaphelenchus xylophilus(PWN) is one of the important infection source of pine wilt disease.Effective measure taken to treat stumps will be helpful to improve the control efficiency of the disease.Therefore,of all the measures taken to prevent and cure the disease,the treatment of stumps is particularly of importance. However,the existing control measures are restricted by lack of manpower,material and financial resources in the affected areas so that they are difficult to be administered effectively.The utilization of wood-rotting fungi desirable as medicine and food to inoculate stumps against the disease enables them not only to decompose,but also to serve as the culture medium of officinal and edible fungi,which will bring a good social and economic benefit to the affected areas of the pine wood disease.Consequently,the people in the affected areas will more actively participate in the treatment of diseased stumps than ever to enhance the effectiveness of the prevention and cure of the disease.This thesis systematically investigate the restraining influence of wood-rotting fungi on the propagation of pine wood nematodes,the function of them in the process of the decomposition of Pinus massoniana specimens,and the function of them in the treatment of stumps of the dead wood caused by PWN.At last,the thesis conducts a preliminary study into the formula for the liquid culture medium of the strain of 6600(Laetiporus sulphureus) which is the most effective in treating diseased stumps,aiming at provide a theoretical basis for the utilization of the fungus in the treatment of stumps suffering from the pine wood nematode disease in the actual production henceforth.The specific findings are as follows:1.13 wood decaying fungi with 22 strains were chosen to examine their relation with Bursaphelenchus xylophilus(PWN).The result indicated that all the others have certain nematicidal effects on PWN except Schizophyllum commune.Among the wood decaying fungi,PWN could not survive on the strains of W10,W11,5452,6600,6221,6320,6284, 6501 absolutely.2.23 strains of wood-rotting fungi were chosen to evaluate their ability to decompose the wood specimens of Pinus massoniana.The results showed that the strains of W10, W11(Fomitopsis pinicola),6600(Laetiporus sulphureus),6923(Coriolus versicolor) and 6284(Poria cocos) have higher ability to decompose Pinus massoniana specimens.3.In this study,the strains of 6600(Laetiporus sulphureus),6923(Coriolus versicolor),W11(Fomitopsis pinicola),6284(Poria cocos) and 6221(Pleurotus ostreatus) were chosen to treat stumps of the dead wood caused by PWN,the ability of decomposing stumps and the effects of PWN were studied in this paper.The results showed that the strain of 6600 has the highest ability to decompose stumps and certain nematicidal effects on PWN.The correlation analysis indicated that the number of PWN had significantly and positively relation with the weight of the samples from stumps.The study sets important basis of using wood-rotting fungi for treating stumps of the dead wood in practice in the future.4.According to the effects of different media on mycelium biomass,the suitable liquid medium and initial pH condition of strain 6600(Laetiporus sulphureus) were studied in this paper.The results indicated that the best prescription is:corn powder 3%,pepton1.5 %,MgSO₄·7 H₂O 0.05%,KH₂PO₄ 0.2%.The suitable initial pH condition was 5.0.The liquid media with V_B1 were not benefit for producing mycelium.