耐盐碱促生菌S4的鉴定及其提高水稻耐盐碱作用研究

Identification of Saline-Alkali Tolerant Growth-Promoting Bacterium S4 and Its Effect on Improving Saline-Alkali Tolerance of Rice

本试验对水稻耐盐碱促生菌S4的菌落形态、生理生化特性进行测定,通过16S rRNA序列对其进行分子鉴定,并对其促生作用进行研究。结果表明:S4菌为人参地微杆菌(Microbacterium ginsengiterrae),具有解磷、解钾作用,还有分泌铁载体与IAA能力,能够在NaCl质量分数7%、pH=10条件下生长。促生试验结果表明,盐碱胁迫下S4菌处理后的水稻幼苗株高、根长较盐碱对照组分别提高66.1%、163.0%,根和叶的SOD、POD、CAT活性及脯氨酸(Pro)含量得到显著提升(P<0.05),可溶性糖(SS)、可溶性蛋白(SP)和丙二醛(MDA)含量显著下降(P<0.05);无盐碱胁迫下S4菌处理后相较于空白对照组根部SOD活性、地上部分Pro含量显著提高(P<0.05),根部SS含量显著下降(P<0.05)。综之,S4菌株可显著提高水稻抗盐碱能力,并有良好的促生效果,具有较大的应用潜力。

In this experiment,the colony morphology,physiological and biochemical characteristics of rice growth-promoting bacteria S4 with saline-alkali tolerace were determined,its molecular identification was conducted by 16S rRNA sequence,and its growth-promoting effect was studied.The results showed that the bacterium S4 was Microbacterium ginsengiterrae,which could dissolve phosphorus and potassium,secrete iron carrier and IAA,and grow under 7%of NaCl and pH 10.The results of growth promotion test showed that the plant height and root length of rice seedlings treated with S4 increased by 66.1%and 163.0%,respectively,compared with saline-alkali control group,and the activities of SOD,POD and CAT and proline content in roots and leaves increased significantly(P<0.05).The contents of soluble sugar(SS),soluble protein(SP)and malondialdehyde(MDA)decreased significantly(P<0.05).Compared with blank control group,the SOD activity in root and proline content in aboveground part increased significantly(P<0.05),while SS content in root decreased significantly(P<0.05)after treated with S4 bacteria under no salt and alkali stress.In conclusion,S4 strain could significantly improve the saline-alkali resistance of rice,and had good growth promotion effect,which had great application potential.