Isolation And Identification Of Endophytic Fungi From Roots Of Three Grasses And Preliminary Study On Their Growth Promoting Effects

Endophytic fungi affect the growth and development of host plants,which has important research and application value.In this experiment,the root tissues of three grasses,Stipa grandis,Cleistogenes squarrosa and Leymus chinensis,were used as materials to isolate and identify.Simultaneously the physical and chemical properties of rhizosphere soil were determined.The endophytic fungi with promoting growth were isolated and screened,and inoculated to the roots of maize with the known AMF and then determine the physiological index of maize seedling.The main results are as follows:(1)483 strains of endophytic fungi were isolated from 1355 root tissues of three grasses and 2 phylum,5 classes,12 orders,24 families,36 genus and 43 species were finally identified.The endophytic fungi in the roots of Stipa grandis belonged to 2phylum: Ascomycota,Basidiomycota;4 phylum: Sordariomycetes,Dothideomycetes,Eurotiomycetes,Agaricomycetes and 13 genus.The dominant genus were Fusarium,Trichoderma,Penicillium,the common genera is Darksidea.The dominant species were Fusarium redolens and Fusarium concolor.The endophytic fungi in the roots of Cleistogenes squarrosa belonged to 1 phylum: Ascomycota;4 classes: Sordariomycetes,Dothideomycetes,Eurotiomycete,Leotiomycetes and 19 genus.The dominant genus were Darksidea,Massaria and Magnaporthe,the common genus were Fusarium,Magnaporthiopsis and Clohesymomyces.The dominant species was Darkside alpha.The endophytic fungi in the roots of Leymus chinensis belonged to 1phylum: Ascomycota;4 classes: Sordariomycetes,Leotiomycetes,Dothideomycetes,Eurotiomycetes and 16 genus.The dominant genus was Fusarium,the common genus were Microdochium,Gaeumannomyces,Corynascella and Clohesymoyces.The dominant species was Fusarium oxysporum.(2)There were abundant endophytic fungi diversity in the three grass root systems.The Shannon Weiner index,Simpson index and Evenness index all showed: Leymus chinensis > Cleistogenes squarrosa >Stipa grandis.(3)Maize seedlings were inoculated with 4 AM fungi and 5endophytic fungi,respectively.We found the plant height,biomass,chlorophyll content,leaf phase to water content,root activity and SOD enzyme activity of maize seedlings were significantly higher than those of the control,while ABA was significantly lower than that of the control.Based on the above results,we found that the treatment of AM fungus GM1 A and endophytic fungus LC-R-311 had the most significant growth promoting effect on maize seedlings.To sum up,the endophytic fungi of the three grasses roots has high abundant resources and diversity.At the same time,some endophytic fungi and AM fungi can effectively promote the growth and development of maize seedlings.This experiment will lay a theoretical foundation for studying the community composition,diversity,biological function of endophytic fungi and their effects on the growth and development.It has an important research prospect and application value.