EFFECT OF GRAPE REPLANT ON THE SOIL MICROBIAL COMMUNITY STRUCTURE AND DIVERSITY

At present, replant obstacle has become an important problem in grape production, and it has seriously restricted the development of the grape industry. This study compared the soil from a replant vineyard and a newly planted vineyard where vine had been grown for 30 years and 3 years respectively. A pot experiment was conducted to investigate the changes of plant growth when grape was grown on root zone soil, sterilized root zone soil and fallow soil from the corresponding vineyards. The variation of the microbial population of the rhizosphere soil, non-rhizosphere soil and fallow soil from different vineyards was studied based on PCR-DGGE approach. The amplified bands of the dominant population were sequenced. The results showed that the plants growth was suppressed by vine replanting, and the plants grew significantly stronger after replant soil sterilization. The bacterial and fungal diversity increased as the period of the grape planting extended. The diversity of the microbial population in the rhizosphere soil was greater than that in non-rhizosphere soil. Cluster analysis showed that the microbial population structure of the rhizosphere soil had the closest association with non-rhizosphere soil after vine replanting and they were different from the population structure of fallow soil. However, the population structure of the rhizosphere soil was different from that of non-rhizosphere and fallow soil in the newly planted vineyard. Comparing to the newly planted vineyard, grape replanting caused a great change in the microbial population of the rhizosphere soil. The relative abundance of Flavobacterium sp. (DQ339585) and Bacillus sp. (AY039821) decreased, while Pedobacter sp. (AJ871084) increased in number Omphalina farinolens (EF413029) appeared, the relative abundance of Pestalotiopsis sp. (DQ657877, DQ657875, DQ657871), Phacidium lacerum (DQ470976) and Lecythophora decumbens (AF353597) decreased, while that of the fungus Pilidium acerinum voucher (AY48709) increased. Among them, Bacillus sp., Flavobacterium sp. and Pestalotiopsis sp. in the rhizosphere soil of the replant vineyard had antagonism for pathogens, and the decrease in their relative amount reduced the ability to resist pathogens. The increasing number of Pilidium acerinum voucher might relate to a serious disease after vine replanting.