摘要
采用有机质耗竭的水稻土样品,添加人工合成的氧化铁和混合碳源（葡萄糖、乳酸盐和乙酸盐）在30℃恒温箱中厌氧富集培养,分别于培养的0（CK）、1、7、14、21、28和50 d通过固体平板培养基分离菌株,对分离菌株进行基于16S rDNA的RFLP分析,测定不同类型菌株的16S rDNA基因序列。同时,将分离的菌株接种至Fe（OH）3-LB液体培养基中,通过厌氧培养观察其铁还原能力变化。结果表明,在7个不同富集培养时间处理中,分别得到了18、5、6、2、5、8和6个RFLP酶切类型。多样性指数计算发现,在厌氧富集培养的0~28 d中,铁还原菌种群结构多样性变化显著,其中培养14 d处理的多样性最小,优势类型所占比例最大。优势类型菌株属于发酵型的芽孢杆菌,说明发酵产H2的微生物对水稻土微生物铁还原过程具有重要作用。
Researches on community structure of iron-reducing bacteria in paddy soil have become particularly relevant,and will provide theoretical basis for better understanding of iron-reducing mechanism.Paddy soil in this study was exhausted first by water-logged incubation,and then cultured with mix carbon source and ferrihydrite at 30 ℃ in anaerobic condition.Single strains were isolated at different time stages [0（as control group）,1,7,14,21,28 and 50 d] with solid agar plate,and analyzed by 16S rDNA-RFLP method.Preserved the single-strains in ferrihydrite-LB liquid medium and observe the iron reduction potential in anaerobic culture.Results showed that 18,5,6,2,5,8 and 6 RFLP types were got in the seven different treatments respectiveyl.Diversity index showed that changes of iron-reducing bacteria community structure were significant,and the 14 d treatment had the smallest diversity and largest domain type ratio.The domain type belongs to ferment bacteria Bacillus in family Firmicutes.It suggests that ferment microorganisms and H2 they produce play an important role in microbial iron reduction.
出处
《西北农业学报》
CAS
CSCD
北大核心
2011年第8期175-181,共7页
Acta Agriculturae Boreali-occidentalis Sinica
基金
国家自然科学基金(40971158)
