Fungal Community Of Birch Infected By Inonotus Obliquus In Different Periods And Preliminary Study On Manual Cultivation Of Inonotus Obliquus

In this paper, the decaying woods caused by Inonotiis obliquus in different periods and healthy woods were sampled in the county Tahe and Huzhong Nature Reserve in the Greater Khingan Mountains area. The decadent process was classified with four periods:Health period; the primary decaying in which cell wall of xylem became thinner, strength decreased, texture, color and toughness changed. Moreover the decadent characteristics could have been observed; Mid-decaying period:in this stage the most of heartwood was rotted and covered with white mycelia. lignin was degraded but could still maintain the integrity of the macro structures, no sclerotia appeared; Completely-decaying period:during the stage the entire macroscopic structures of the timber had been completely destroyed, the timber has changed into a powder condition, there sclerotia appeared. After the separation, purification and identification confrontation culture, we could initially reveal the influences of this medicinal fungi colonization on the changes of endophytic fungi in health birch and fungal communities in the rotten woods during each period of colonization. Culture on the biological characteristics of Inonotus obliquus was done, and then according to the results there furthermore conducted the artificial fungus bag cultivation which could provide new references for Inonotus obliquus artificial cultivation. The major results as follows:1、The entophytic fungal communities composition of birch has greatly changed due to the intrusion of Inonotus obliquus. The colony of healthy birch was simple, after the decadent the types of fungi and the separated frequency were significantly increased. During the completely decaying period, the communities of the fungi in the birch were basically stable but composition became the most complex. The pioneer fungi were Penicillium, Eurotium,Puraphoma, Trichoderma. Aspergillus, Myxotrichum, Alternaria, Paecilomyces, Cladosporium, Phoma.2、The difference of fungal species in pre-, mid-term and completely decaying period was not obvious. Relatively there was the biggest difference appeared in the isolation frequencies of Inonotus obliquus and other pioneer microorganisms between the three periods. The frequency of pioneer fungi was obviously more than Inonotus obliquus in primary decaying period. And then the frequency of the former was almost equal to the latter in the mid-term decaying. At a middle stage, the frequency of pioneer fungi was less than the other. In the totally rotten woods, the frequency of Inonotiis obliquus was far exceeding the pioneer fungi. 3、After the separation and purification, there were19genera (species) identified from the healthy woods;31genera (species),l undefined Ascomycetes fungi and1undefined basidiomycetes in wood of primary decaying period;30kinds of fungal species and1undefined Mitosis fungi in wood of mid-term decaying woods; There were altogether44genera (species) separated from the totally decaying woods caused by the Inonotus obliquus. There was the most abundant fungal species separated in the bark, followed by the order of the ministry of sapwood, heartwood ministry and ministry of decadent.4、There was one isolate belonging to Leptodontium separated from the decaying birch sampled in the Greater Khingan Mountains area. After the morphological identification, the new found species was considered as one new species and named Leptodontium xinganensis Liu.X.F.&Wu.S.J. nov.sp.. After morphological description, according to the published the literature, the retrieve table of the genus has been established. Combined with morphological identification and molecular identification methods, a newly recorded species Oidiodendron griseum in China was found.5、The hz3stran was inoculated in PDA.After the15days cultivation in35℃,then cultivate in normal atmospheric temperature,the sclerotia was induced.It is the first reports of sclerotia inducing on manual culture.6、The mycelium growing conditions of Inonotus obliquus were studied. The result showed that the most suitable carbon source was maltose, the best nitrogen source was soybean meal, and C/N of media was20:1. pH was7. temperature conditions was in25℃7、Two strains with good activity (hz3and thl)was screened. The best formulations of artificial cultivation conditions were vastly different with strains changing. For the hz3strain, Formulation3was the most suitable, while for the thl strain, the Formulation2was the best.