Diversity And Ecological Distribution Of Endophytic Fungi Associated With Bletilla Ochracea In Guizhou, China

All the 331 non-sporulated strains (32.2% to the total isolates) were grouped into 51 fungal morphotypes according to similar cultural characters. These 51 morphotypes were identified to 39 taxa, of which 17 were identified to species, 21 to genus, 1 to order, and 12 were unidentified. Of the 39 taxa above, there were 37 Ascomycota and 2 Basidiomycota.Based on methods of ITS-PCR, random cloning, DGGE and phylogenetic analysis, fungal communities were detected and identified within leaves and roots of B. ochracea collected from Qingzhen city in Guizhou. A total of 203 ITS clones were obtained from leaves and were identified to 18 different OTUs, including 15 Ascomycota (91% to total clones) and 3 Basidiomycota (9%), among of these, Mycosphaerella, Alternaria, Colletotrichum, Leptosphaerulina, Dioszegia and Ascomycete sp.2 were dominant species. Correspondingly, the 211 clones were discovered from roots and were identified to the 10 OTUs, contained 9 taxa of Ascomycota (54%) and 1 taxon of Basidiomycota (46%), of these, Sebacina, Fusarium, Gibberella and Nectria were dominant species. The result showed that fungal diversity in leaf tissues (H', 2.354) were higher than that in root tissues (H', 1.560), and also revealed that fungal communities within leaves and roots were significantly different from each other. Comparing with traditional method, fungal communities detected by molecular method were quite different, and some dominant species or common species could not be detected simultaneously by both methods.The results of ecological analysis of fungal communities within roots and leaves from 5 geographic regions in Guizhou showed that species of Epulorhiza, Ceratorhiza and Sebacina genera in Basidiomycota were dominant with 56.40% to total relative frequency (RF), and species of Phomopsis and Fusarium genera in Ascomycota were also common with 10.74% to total RF in root tissues. And within leaves, the dominant species were in the Colletotrichum (68.26%) , Guignardia (14.10%) and Cercospora (7.36%) genera. However, ecological distribution of these dominant species were a bit different among sampling sites; Richness and distribution of endophytic fungi were significantly affected by different sampling sites; Shannon-Wieiner diversity index (H') of endophytic All the 331 non-sporulated strains (32.2% to the total isolates) were grouped into 51 fungal morphotypes according to similar cultural characters. These 51 morphotypes were identified to 39 taxa, of which 17 were identified to species, 21 to genus, 1 to order, and 12 were unidentified. Of the 39 taxa above, there were 37 Ascomycota and 2 Basidiomycota.Based on methods of ITS-PCR, random cloning, DGGE and phylogenetic analysis, fungal communities were detected and identified within leaves and roots of B. ochracea collected from Qingzhen city in Guizhou. A total of 203 ITS clones were obtained from leaves and were identified to 18 different OTUs, including 15 Ascomycota (91% to total clones) and 3 Basidiomycota (9%), among of these, Mycosphaerella, Alternaria, Colletotrichum, Leptosphaerulina, Dioszegia and Ascomycete sp.2 were dominant species. Correspondingly, the 211 clones were discovered from roots and were identified to the 10 OTUs, contained 9 taxa of Ascomycota (54%) and 1 taxon of Basidiomycota (46%), of these, Sebacina, Fusarium, Gibberella and Nectria were dominant species. The result showed that fungal diversity in leaf tissues (H', 2.354) were higher than that in root tissues (H', 1.560), and also revealed that fungal communities within leaves and roots were significantly different from each other. Comparing with traditional method, fungal communities detected by molecular method were quite different, and some dominant species or common species could not be detected simultaneously by both methods.The results of ecological analysis of fungal communities within roots and leaves from 5 geographic regions in Guizhou showed that species of Epulorhiza, Ceratorhiza and Sebacina genera in Basidiomycota were dominant with 56.40% to total relative frequency (RF), and species of Phomopsis and Fusarium genera in Ascomycota were also common with 10.74% to total RF in root tissues. And within leaves, the dominant species were in the Colletotrichum (68.26%) , Guignardia (14.10%) and Cercospora (7.36%) genera. However, ecological distribution of these dominant species were a bit different among sampling sites; Richness and distribution of endophytic fungi were significantly affected by different sampling sites; Shannon-Wieiner diversity index (H') of endophytic fungi from roots was higher than that from leaves; Sorensen index (Cs) of endophytic fungi from roots was very low, and Cs of endophytic fungi from leaves much higher than that from roots. Fungal communities within roots and leaves were dramatically different from each other, and their Cs was nearly to zero; Shannon-Wieiner diversity index of endophytic fungi from roots had a certain correlation with longitude, altitude and latitude, however, there was no correlation within leaves.This is the first detailed investigation of fungal communities, distribution and diversity within roots and leaves of B. ochracea from different sampling sites, and the results above will help us for understanding comprehensively fungal diversity within plants and their geographical distribution. It is significant for us to realise and utilize important resources of endophytic fungi from orchid plants in this study.