应用T-RFLP技术分析不同土壤温度和施肥方式下设施土壤细菌群落结构

Study on Bacterial Community Structure in Greenhouse Vegetable Soils Affected by Soil Temperature and Fertilization Pattern using T-RFLP Technology

采用末端限制性片段长度多态性分析(T-RFLP)和荧光定量PCR技术,研究了两种土壤温度(对照不增温,10°C ±2°C;增温,20°C ±2°C)和两种施肥方式(对照不施肥;鸡粪有机肥底肥+尿素追肥)对土壤细菌群落结构及其多样性和数量特征的影响。结果表明:相同施肥方式下,土壤增温增加土壤速效养分含量,尤其在施肥时增加幅度更明显。分析显示施肥对土壤细菌群落结构的影响在不同土壤温度条件下表现不同。土壤不增温条件下,施肥增加细菌Pielou均匀度指数和Shannon-Weiner多样性指数,Simpson优势度指数降低;土壤增温条件下,则效果相反。与不增温比,增温使土壤细菌Pielou均匀度指数和Shannon-Weiner多样性指数降低,但物种个体数和Simpson优势度指数增加明显。增温改变了土壤细菌群落结构,62 bp和93 bp两种限制性末端片段在土壤增温条件下优势度提高,主要包括共生菌和杆菌。

The bacterial community structures in greenhouse vegetable soils were determined under different soil temperatures and fertilization patterns by the techniques of terminal restriction fragment length polymorphism (T-RFLP) and fluorogenic quantitative PCR. The results showed that soil available nutrients were increased with the increase of soil temperature under the same fertilization form, the increased effect was more obvious under fertilizer treatment. The effects of fertilization on soil bacterial community were different under different soil temperatures. Fertilization increased Shannon-Weiner and Pielou indexes while decreased Simpson index under the no heating condition, but on the contrary under the heating condition. Compared with the no heating treatment, the heating treatment decreased Shannon-Weiner and Pielou indexes but obviously increased species number and Simpson index. Temperature changed the community structure of soil bacteria and the increase of temperature promoted Simpson indexes of T-RFs of 62 bp and 93 bp, mainly including symbiotic bacteria and bacillus.