Endophytic Mycoflora Of Selaginella: Diversity Patterns And Effect On Drought Tolerance In Wheat

Endophytic fungi almost exists in all have been studied plants, through long-term cooperative coevolution with host plants, have established a stable harmonious symbiosis with host plants, and some endophytic fungi can produce the same or similar bioactive substances as host plants. Current researched and recorded fungi accounted very little proportion of the fungi on earth, now domestic and foreign research situation of the endophytic fungi more distribution on the grasses and plant trees, the diversity of endophytic fungi research has a larger development space.Selaginella is medicinal plants with strong drought resistance, this experiment separated endophytic fungi from four different types of selaginella:Selaginella trachyphylla(JiYuan),Selaginella sinensis(JiYuan),Selaginella sinensis(LuoYang), Selaginella sinensis(PingDing Shan). Through morphology and molecular biology identification, preliminary classification those endophytic fungi in 23 genera, besides, other two strains have not identified. Among this, Alternaria sp.,Fusaritm sp.,Penicillium sp.,Podospora sp.have higher separate frequency than other strains. In addition to the above four kinds of endophytic fungi, Chaetomium sp.,Nigrospom sp.,Aspergillus sp.,etc are distribution in those four different types Selaginella. And Alternaria sp,Fusaritm sp also the dominant species in those four different types Selaginella. According to the colonization rate, each part of endophytic fungi colonization rate is over 50%, Shannon-Wiener diversity index is about 2.2, that means there are abundant endophytic fungi colonization in selaginella.Alternaria sp.and Fusaritm sp.are the dominant species in Selaginella trachyphylla’s(JiYuan) leaf and stem,but in the root,Alternaria sp. and Penicillium sp. are the dominant species. Pestalotiopsis sp. aslo in Selaginella sinensis(JiYuan),Selaginella sinensis(LuoYang),Selaginella sinensis(PingDingShan),but never separated out from Selaginella trachyphylla(JiYuan). Xylaria sp.exist in Selaginella trachyphylla(JiYuan) and Selaginella sinensis(JiYuan), but never found in Selaginella sinensis(LuoYang) and Selaginella sinensis(PingDingShan). That means, the colonization and distribution of endophytic fungi are related to the nature of organization, the host species, geographical location, climate condition and other factors.By measuring part of physical index of wheat that colonization by endophytic fungi under drought stress, preliminary selected several endophytic fungi can improve wheat drought resistance at varying degrees:fungi B12 separated from Selaginella trachyphylla’s(JiYuan) leaf and stem, fungi C23 separated from Selaginella sinensis’ s(JiYuan) root, fungi A6 separated from Selaginella sinensis’ s(JiYuan) leaf and stem, fungi E4 separated from Selaginella sinensis’ s(LuoYang) root, fungi A13,B3 separated from Selaginella trachyphylla’s(PingDingShan) leaf and stem. They respectively belonged to Xylariaceae sp.,Trichoderma sp.,Fusaritm sp.,Phomopsis sp., and Colletotrichum sp..By analysis under drought stress, the change of physiological indexes of wheat that colonization by endophytic fungi, presumed that drought impact on chlorophyll content in wheat body, will only cause a range of reduced before reached a certain degree of drought, its content in wheat body is related to other factors, such as the age and growth environment of wheat; along with the environmental deterioration in wheat growth, some endophytic fungi’s beneficial effects will turn negative. in addition, some endophytic fungi have great influence to some tissues and organs activity of the host plant, while they inhibit the growth of this part of the tissue and organ, they improved the activity of the parts or replace the function of the parts.This experiment studied the diversity of endophytic fungi in different selaginella, analyzed the factors that affecting the distribution of the endophytic fungi in the host plant. By screening drought resistance function endophytic fungi through the separated endophytic fungi of selaginella, preliminary discussed the influence of endophytic fungi on plant growth and drought resistance in seedling stage, and selected several endophytic fungi strains can promote wheat drought resistance at some degree,enriched the knowledge of endophytic fungi’s population, have a certain role in promoting the development of energy conservation and environmental protection farming preparation.