Diversity Of Species And Community Of AM Fungi In The Rhizosphere Of Plants Under Different Climatic Conditions

The arbuscular mycorrhizal(AM)fungi resource,species diversity,soil physicochemical properties and AM fungal species diversity in relation in the rhizosphere of Robinia pseudoacacia L,Populus simonii Carr,Hippophae rhamnoides Linn and Caragana Korshinskii Kom in Ningshan and Hengshan,extraction of total microbial DNA by enzyme cleavage and analysis of AM fungi community diversity by PCR-DGGE were reported in this research.The results were as follow:1.The resources of AM fungi5 genus 26 species of AM fungi were identified from the rhizosphere of plants in Ningshan and Hengshan:Glomus fasciculatum,G.mosseae,G. aggregatum,G.geosporum,G.deserticola,G.constrictum,G.albidum,G.claroideum,G.caledonium,G.etunicatum,G.ambisporum,G.microaggregatum,G.monosporum,G.multicaule,G. intraradices,G. coronatum,G.manihotis,G.reticulatum,G.pansihalos,G.microcarpum,Archaeospora leptoticha,Acaulospora denticulate,Gigaspora margarita,Gi. Decipens,Scutellospora heterogama,Sc.rubra and G.constrictum was the dominant genera in Ningshan and Hengshan.2.The distribution of AM fungiSpecies richness index of AM fungi was different between different sampling points and different host plants.Species richness index of AM fungi in various sampling points of Ningshan and Hengshan ranged from 6 to 11 and 4 to 14.Species of AM fungi in the rhizosphere of Hippophae rhamnoides Linn were 2~4 richer than the other three plants and in Hengshan were richer than in Ningshan as 10.67 and 8.17. AM fungal spore density in Ningshan was significantly higher than in Hengshan as 951.3 spores/100g and 245.2 spores/100g. AM fungal colonization rate and Shannon indexes had no significant difference between different regions and plants.The result of correlation analysis showed that spore density significantly correlated colonization rate except Caragana Korshinskii Kom in Hengshan,Shannon index had no significant correlation with spore density,and colonization rate except Populus simonii Carr in Ningshan.3.The influence of soil physicochemical properties on the diversity of AM fungi The result of correlation analysis between soil physicochemical properties and AM fungal diversity index showed that pH negatively correlated with colonization rate,spore density and Shannon index in the rhizosphere of Robinia pseudoacacia L in Hengshan.Available P and available N were positive correlation in the rhizosphere of Robinia pseudoacacia L in Ningshan and Populus simonii Carr in Ningshan and Hengshan,Organic matter on the contrary.Path analysis indicated that soil physicochemical properties on different host plants infected AM fungi spore density or colonization rate on different degree.4.The community diversity of AM fungi in different climatic regionsThe result of DGGE analysis showed that the number,mobility and intensity of each band were different between different sampls.That indicated the AM fungal community structure were different in different sampling points.The digital analysis of the location and brightness of each band on the map showed that each samples had different species richness and Shannon index of AM fungi.Similarity matrix showd the similarity varied between different samples.Cluster analysis showed that 18 samples can be divided into four groups.Samples from differernt regions and different plants classified as an ethnic group,indicating AM fungi have no strict specificity with plants and regions. In groups II and III samples from the same region or plants, showed that the AM fungal community structure had a certain degree of stability in the species and region.