Diversity Of Endophytic Fungi And Rhizosphere Soil Fungi And Growth-Promoting Effects Of Cymbidium Kanran

Cymbidium kanran is a plant in the genus Cymbidium of the Orchidaceae family and has high ornamental and economic value.Due to the artificial destruction of habitats,excessive collection of orchid resources and climate change,the research on conservation of C.kanran resources is urgently needed.Fungi have an important effect on orchids,orchids and symbiosis with fungi,the use of fungi to carry out conservation work and efficient reproduction of orchids is of great significance.In this study,the specific relationship between fungi and C.kanran was analyzed by collecting C.kanran root tissue and root-soil in field samples of C.kanran distribution area(Hainan province,Yunnan province,Guizhou province,Hunan province,Fujian province)in China.Purified,isolated and identified endophytic fungi in the roots of C.kanran in two sites,and further explored the effect of the isolated fungi on the symbiotic germination of C.kanran seeds and the effects of fungi on the tissue culture seedlings of C.kanran under culture conditions.In the pot experiment,the fungus made by adding different endophytic fungi to C.kanran was selected,and finally the endophytic fungi with good promoting effect were selected.The main results are as follows:(1)Using bioinformatics analysis methods to compare the differences in microbial diversity and composition in different regions,the results show that the species abundance of fungal communities in the roots and roots of C.kanran in different provinces is not uniform,the structure of species composition varies significantly,and Location has a significant effect on the diversity of fungal communities.(2)Isolate the root samples of C.kanran in Fujian province and Hainan province,and determine 14 endophytic fungi,including 6 in Fujian province and 8 in Hainan province,belonging to Ascomycota,Basidiomycota,Mucoromycota.The fungi isolated in both areas were Umbelopsis nana of Mucoromycota.(3)The results of in vitro co-cultivation of C.kanran seedlings showed that the lethality rate of Xylaria sp.And Nodulisporium sp.To seedlings reached 100%.The results of C.kanran seedling pot experiment showed that different fungi had different degrees of promotion effects on seedlings.Among them,Xylaria sp.had the most significant effect on growth,and the increase in fresh weight was 3.97 times that of the control group.Nine endophytic fungi have a positive effect on potted seedlings of C.kanran,and they have significant effects on fresh weight,number of new roots,changes in root length,plant height,leaf length,and photosynthetic pigment content.Freehand slicing of the roots of C.kanran seedlings with significant effects can reveal a large number of hyphae and needle-like crystals in the root cells.Re-separating the roots of mycorrhizal can isolate the same strain.