Study On The Composition Of Internal Microflora Of Decayed Wood Of Betula Platyphylla And Its Promoting Growth Of Mycelia Of Inonotus Obliquus

In this paper,the decayed wood of Betula platyphylla that is infected by Inonotus obliquus collected from Mohe City,Heilongjiang Province was divided into sections according to the decayed degree,respectively,from inside to outside decayed area(wood texture structure changes,lignin has basically been degradation),discoloration area(the initial degradation of cell wall of xylem cells,dark),the three parts health area and sclerotia part of Inonotus obliquus.The samples of the above four parts were isolated,purified and identified in the laboratory.After that,the samples were sequenced and analyzed by microbial community diversity spectrum.Combined with the results of laboratory isolation and purification,the effects of colonization on internal microflora of Inonotus obliquus and the composition of microbial community in each colonization period of betula platyphylla were preliminarily revealed.At the same time,the obtained Internal strains were co-cultured with Inonotus obliquus,and the strains with significant promoting or inhibiting effects on Inonotus obliquus growth were screened according to the growth of Inonotus obliquus,which could provide help for artificial cultivation of Inonotus obliquus and inhibition of rot of birch wood.The main research contents are as follows:1.In this paper,we studied how the internal microflora of Betula platyphylla was affected during the decomposition of wood by Inonotus obliquus.The decayed wood of Betula platyphylla was analyzed by traditional microbial isolation and high throughput sequencing.Through the hole Inonotus obliquus separation and identification of fungi of different positions of the birch,received 15 kinds of fungi,there were more culturable fungi in decay area,and the quantity of penicillium,trichoderma,Mucor is more than the health area,such as color change area and the sclerotium of Inonotus obliquus,combined with the formation of the decadent reason,can explain penicillium,trichoderma,Mucor and other fungi,although not cause birch decay of pathogenic bacteria,however,it was possible that they could accelerate the decay of betula platyphylla after it was infected with Inonotus obliquus.At the same time,the Internal bacteria and actinomycetes in different parts of Betula platyphylla were tested,and 9 species of bacteria and 1 actinomycetes were isolated and identified,which indicated that the Internal bacteria and actinomycetes in different parts of Betula platyphylla were not suitable for culture.2.The results of high-throughput sequencing showed that the fungal community of Betula platyphylla was greatly changed during the decomposition of wood by Inonotus obliquus.The composition of fungal community was abundant in healthy areas of Betula platyphylla.The number of fungi decreased significantly due to the secretion of anti-decay substances in the discoloration area caused by the infection of Inonotus obliquus.The number of fungi in the decayed area was slightly higher than that in the discoloration area,but it was different from that in the healthy area.However,no significant changes of Internal bacteria and actinomycete communities were observed in the invasion of Inonotus obliquus.Compared with the results of high-throughput sequencing,more unculturable endophytes were not isolated.3.The inhibition rate was calculated by the confrontation test between the Internal microflora of Betula platyphylla and Inonotus obliquus.It was found that the fungi penicillium and Trichoderma had obvious inhibition effect on the growth of Inonotus obliquus.Meanwhile,The genus Verticillium and Peniophora showed promoting effect on the growth of Inonotus obliquus.Among the bacteria,Bacillus velezensis and Bacillus Siamensis had significant inhibitory effect on the growth of the mycelium of Inonotus obliquus,and no strain bacteria was found to have certain growth promoting effect on Inonotus obliquus.Saccharopolyspora and two strains to be identified in the actinomycetes had a certain inhibitory effect on the mycelial growth of Inonotus obliquus.At the same time,it was found that yeast L2 had a certain promoting effect on the growth of the mycelia of Inonotus obliquus in the early stage,but when the two colonies were close to each other in the later stage,it had a certain inhibiting effect on Inonotus obliquus because of nutrient competition.4.In this study,we investigated the effect of Yeast L2(Cyberlindnera misumaiensis)on Betula platyphylla wood block infection,and found that yeast L2 could promote Betula platyphylla wood block infection to a certain extent.On this basis,for the study of yeast L2 on by infection of Inonotus obliquus have influence on the decay rate of birch,using high pressure sterilization and surface disinfection two different ways of dealing with wood,wood inoculated with yeast L2 rots faster.The results showed that yeast L2 had a certain promotion effect on the infection of Inonotus obliquus,and the promotion effect was the best under the condition of autoclaved sterilization.Meanwhile,it was proved that the Internal microflora of healthy Betula platyphylla had a certain inhibition effect on the infection of Inonotus obliquus.