Soil Microbial Community of Vineyard with Different Planting Years and Correlation Analysis with Fertility Factors

Yunnan is one of the nine grape planting regions in China. The continuous cropping obstacle of grape is gradually getting more and more serious with planting years. In order to reveal the microbial reasons of these obstacles, rhizosphere microbial community and soil fertility change of vineyard with different planting years(3, 6, 10, 30 years) in Mile county, Yunnan Province were determined using the standard dilution-plating technique and MPN. The results showed that the amount of bacteria was the most abundant, followed by actinomyces in all planting-years samples. Total microbe population, B/F and A/F of soils increased in the beginning and then decreased with the cultivation years, the peak of those were observed with 6 years samples and the lowest were with 30 years samples. The amount of fungi continuously increased with the cultivation years. Abiogenous azotobacter, nitrifying bacteria, inorganic phosphorus bacteria, organic phosphorus bacteria and cellulose decomposing bacteria decreased with cropping year increase, and their population followed the order: inorganic phosphorus bacteria > abiogenous azotobacter > cellulose decomposing bacteria > organic phosphorus bacteria > nitrifying bacteria. The result also indicted that rhizosphere soil shifted from bacteria type to fungi type significantly after continuous cropping and the beneficial bacteria populations were decreased. Based on soil fertility index, the fertility level increased in the beginning and then decreased with the cultivation years. The principal component analysis showed that available K was related to several microbial amounts, and fertility level was related to planting-years.