葡萄连作对土壤细菌和真菌种群的影响

分别采集种植葡萄30年的连作园和3年的新植园根围土、非根围土及葡萄园周边的空地土壤，采用PCR DGGE技术，研究葡萄连作对土壤细菌和真菌种群结构及多样性的影响，并对分离出的优势种扩增条带进行测序.结果表明：葡萄连作后土壤细菌和真菌的多样性增加，且根围土壤的微生物多样性高于非根围土壤.聚类分析显示：葡萄长期连作后根围与非根围土壤细菌和真菌的种群结构趋于一致，两者不同于空地土壤；而短期种植葡萄的根围土壤细菌和真菌的种群结构不同于非根围土壤和空地土壤.与新植园相比，连作园根围土壤中微生物种群结构发生较大变化，细菌中Flavobacterium sp.（DQ339585）和Bacillus sp.（AY039821）种群数量减少，Pedobacter sp.（AJ871084）种群数量增多；真菌中Omphalina farinolens（EF413029）出现，Pestalotiopsis sp.(DQ657877,DQ657875,DQ657871）、Phacidium lacerum（DQ470976）和Lecythophora decumbens（AF353597）种群数量减少，Pilidium acerinum voucher（AY48709）种群数量增多.其中Bacillus sp.、Flavobacterium sp.和Pestalotiopsis sp.对病原菌具有颉颃作用，连作园根围土中上述微生物种群数量的减少，不利于葡萄对病原菌的颉颃；Pilidium acerinum voucher数量的增加可能与葡萄连作后病害加重有关.

Effects of grape-replanting on soil bacterial and fungal populations

Rhizosphere and non-rhizosphere soil samples were collected from the vineyards having been planted for 3 and 30 years, and PCR-DGGE technique was adopted to study the effects of grape-replanting on the population structure and diversity of soil bacteria and fungi. The bacterial and fungal diversities were higher in 30-year-planted vineyard than in 3-year-planted vineyard, and higher in rhizosphere soil than in non-rhizosphere soil. After 30 years replanting, the population structure of bacteria and fungi approached the same in rhizosphere soil and non-rhizosphere soil hut differed from that in fallow soil; while in the 3-year-planted vineyard, the population structure in rhizosphere soil was different from that in non-rhizosphere soil and fallow soil. Comparing with that in 3-year-planted vineyard, the rhizosphere soil microbial population in 30-year-planted vineyard had a greater change. In bacterial population, Flavobacterium sp. (DQ339585) and Bacillus sp.(AY039821) decreased while Pedobacter sp. (AJ871084) increased; in fungal population,Omphalina farinolens ( EF413029 ) appeared, Pestalotiopsis sp. ( DQ657877, DQ657875,DQ657871 ), Phacidium lacerum ( DQ470976 ), and Lecythophora decumbens ( AF353597 ) decreased, while Pilidium acerinum voucher (AY48709) increased. Bacillus sp., Flavobacterium sp. , and Pestalotiopsis sp. had antagonism to pathogen, and their decrease reduced the resistance of grape against pathogen. The increase of Pilidium acerinum voucher might relate to the severe disease after grape- replanting.