促进水稻耐盐碱细菌S4菌株的筛选鉴定及其效果研究

Characteristics of Bacterial Strain S4 and Its Effect on Enhancement of Rice’s Tolerance to Saline-alkali

自然界存在可显著提高植物耐盐碱能力的微生物,利用选择性培养基,在盐含量0.60%、pH8.5条件下,将供试菌株与水稻幼苗共同培养于人工光照培养箱中,通过根长、株高等生长指标对最优菌株进行筛选,结果从450株分离物中筛选出对盐碱胁迫下水稻生长促进作用最佳的一株菌,S4菌株。经16SrRNA序列相似性比对,S4菌株鉴定为人参土微杆菌(Microbacterium ginsengiterrae),其可在盐含量4.0%和pH9.5的盐碱环境中良好生长。在水培试验中,与未接菌盐碱胁迫对照相比,接种S4菌株可提升水稻幼苗干质量4.7%;且在银川盐碱地试验中,接种S4菌株的水稻植株相对未接菌组亩产提升10.8%。

There are some microorganisms in the natural world,which can significantly improve higher plants’resistance to saline-alkali stress.The selective medium was used to isolate the salt-tolerant bacterial strains,and then these strains were applied for growth of the rice seedlings in the plant growth chamber under the conditions of 0.60%NaCl and pH 8.5.The best strains were chosen based on plant’s height,root’s length.The top performance of strain S4 was obtained in 450 isolates.Strain S4 was identified as Microbacterium ginsengiterrae based on the 16S rRNA sequence similarity.Strain S4 grew well under the adverse conditions of pH 9.5 and 4.0%of NaCl.In the pot experiment,S4 increased the growth of the rice seedling by 3.7%DW compared with the uninoculated control.In the saline-alkali paddy field in Yinchuan of Ningxia,the rice innoculated with strain S4 boosted the grain yield by 10.8%compared with rice not inoculated with strain S4.