铝胁迫对酸性红壤古菌amoA基因多样性的影响分析

EFFECTS OF ALUMINUM STRESS ON amoA GENETIC DIVERSITY OF ARCHAEA IN ACIDIC RED SOILS

通过PCR-RFLP技术构建红壤丘陵区土壤氨氧化古菌amoA基因文库,比较分析典型森林土和农田土中氨氧化古菌种群结构对铝胁迫的响应。通过对628个amoA基因克隆子进行了PCR-RFLP指纹图谱分析,共获得62个独特的基因操作分类单元(operational taxanomical uints,OTUs),进一步对62个OTUs开展Blast和RDP分类分析(相似性97%-100%),结果表明:森林和农田土壤样品中100%的氨氧化古菌属于泉古菌门(Crenarchaeotes),分布于4个基因族(Cluster1-4),Cluster 1在所有测试样品中占明显优势。农田土壤中氨氧化古菌的丰度和多样性要高于森林土壤,但随着铝胁迫浓度的增加,农田土壤中氨氧化古菌丰度和多样性降低更明显,均匀度却有所上升。可见,铝胁迫导致土壤氨氧化古菌群落结构改变,高铝胁迫能促使氨氧化古菌发生适应性变化,有可能演变出优势种群。

In this study,the genes library was constructed by using the PCR-RFLP technology and the community characteristics of ammonia-oxidizing archaea between the forest soils and the agriculture soils under different Al-treated concentrations were comparatively analyzed.A total of 628 of amoA genes cloned from 6 soil samples were analyzed.And 62 unique restricted fragment length polymorphism fingerprints were identified and sequenced.DNA sequence was analyzed by Blast and RDP classification(similarity 97 to 100%).The results showed that all of the ammonia-oxidizing archaea group in soil samples belonged to Crenarchaeotes and distributed in 4 gene clusters(Cluster 1-4).Among them,cluster 1 was dominant in all test samples.The abundance and diversity of ammonia-oxidizing archaea in agriculture soils were higher than that in forest soils.However,with the increase of aluminum stress concentration,the abundance and diversity of ammonia-oxidizing archaea in agriculture soils decreased significantly,but the evenness increased.It indicated that aluminum stress can change the community structure of soil ammonia-oxidizing archaea,and high aluminum stress can promote the adaptive change of oxygen ammonia-oxidizing archaea,which may evolve into a dominant population.