稻草还田对水稻土固氮基因(nifH)组成结构和多样性的影响  

Effects of rice straw returning on the community structure and diversity of nitrogen-fixing gene (nifH) in paddy soil

作　　者：张苗苗[1,2,3] 刘毅[1,2] 盛荣[1,2] 秦红灵[1,2] 伍延正[1,2,3] 魏文学[1,2] 

机构地区：[1]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,长沙410125 [2]中国科学院桃源农业生态试验站,长沙410125 [3]中国科学院大学,北京100049

出　　处：《应用生态学报》2013年第8期2339-2344,共6页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(41071181);中国科学院创新团队项目(KZCX2-YW-T07)资助

摘　　要：以中国科学院桃源农业生态试验站长期定位施肥试验为平台,选取稻草还田(C)、氮磷钾(NPK)、氮磷钾加稻草还田(NPK+C)和不施肥对照(CK)4个处理,在晚稻的分蘖期、孕穗期和成熟期分别采集土样,利用实时定量PCR(Q-PCR)和末端限制性片段多态性(T-RFLP)等分子生物学方法研究长期稻草还田对水稻土含nifH基因固氮微生物群落丰度、组成和多样性的影响.结果表明:与对照相比,稻草还田和单施化肥处理均显著增加nifH基因的丰度(分蘖期除外),NPK+C处理中含nifH基因的微生物数量最高;nifH基因组成也受到长期施肥的影响,其中CK处理nifH基因组成与各施肥处理明显不同,C与NPK处理间nifH基因组成存在一定差异,而NPK与NPK+C处理间无显著差异.长期施肥不会引起含nifH基因微生物群落多样性的显著改变.可见,稻草还田不仅引起nifH基因群落的组成发生变化,而且导致其数量显著增加,因而可增加土壤的固氮能力.Taking a long-term fertilization experiment in Taoyuan Agro-ecosystem Research Station under Chinese Academy of Sciences as the platform, and selecting four treatments （no fertilization, CK; rice straw returning, C; nitrogen, phosphorus and potassium fertilization, NPK; and NPK＋C） as the objects, soil samples were collected at the tillering, booting and maturing stages of rice, and the abundance, composition and diversity of nifH-containing bacterial community were measured by real-time quantitative PCR and terminal restriction fragment length polymorphism （T-RFLP）, aimed to understand the effects of rice straw returning on the nifH-containing bacterial community in paddy soil. Compared with CK, treatments NPK＋C and NPK increased the abundance of nifH-containing microorganisms significantly （except at tillering stage）, and NPK＋C had the highest abundance of nifH-containing microorganisms. Under the effects of long-term fertilization, the composition of nifH gene community in CK differed obviously from that in the other three treatments. The nifH composition had definite difference between C and NPK, but less difference between NPK and NPK＋C. Long-term fertilization did not induce significant changes in nifH diversity. Therefore, long-term rice straw returning not only induced the changes of nifH gene community composition, but also resulted in a significant increase in the abundance of nifH-containing community, and hence, the increase of soil nitrogen fixing capacity.

关 键 词：稻草还田 NIFH基因 基因丰度 群落组成 多样性 

分 类 号：S154.3[农业科学—土壤学]