The category and distribution of arbuscular mycorrhizal fungi from the rhizosphere of eight cultivated leguminous shrubs

Soil samples of eight leguminous shrub plants were collected respectively from the experimental field, and the plants were Cassia tora, Dendrolobium triangulare, Amorpha fruticosa, Sophora davidii, Crotalaria pallida, Indigofera amblyantha, Cajanus cajan and Leucaena leucocephala which cultivated in Guiyang. Each soil sample was collected from each sites at three depths in the soil profile: 5-10, 10-20 and 20-30 cm, respectively. This study mainly analyzed the infection rate, spore density, species and the diversity of arbuscular mycorrhizal fungi. The results indicated that the eight leguminous shrub plants had a higher infection rate of AM fungi, the infection rate of AM fungi for C. pallid was the highest, up to 80.8%; Soil available phosphorus had significantly negative correlation with the infection rate(r=-0.733,P=0.039); The spores of AM fungi mainly distributed in the 5-20 cm soil layer, the spore density of C. pallida at the 5-10 cm layer was the highest;Spore density were significantly affected by the host plants and soil layers (F=100.497, P<0.001);The dominant species of AM fungi were Glomus liquidambaris and Acoaclospora delicate, which were detected in the soil of eight leguminous shrub plants. It was important to inoculate the dominant AM fungi for leguminous shrub plant in karst area and do other related researches about rhizobia. What's more, these researches had a great effect on improving animal husbandry production and restoring degraded ecosystem.