NaHCO3胁迫对甘蓝型油菜幼苗生长的影响及其耐盐候选基因预测

Effects of NaHCO3 Stress on Growth of Brassica napus Seedlings and Prediction of Candidate Genes Related to Salt Tolerance

为研究甘蓝型油菜耐碱性盐机制,以甘蓝型油菜耐盐品系‘2205’与敏盐品系‘1423’为试验材料,通过人工模拟碱性盐胁迫,研究NaHCO3对甘蓝型油菜幼苗生理的影响及耐盐相关基因的表达量变化,分析耐盐生理指标与基因表达量的相关性,初步预测耐盐候选基因。结果表明:随着碱性盐NaHCO3(75mmol/L NaHCO3)胁迫时间的延长,幼苗叶片的电导率、抗氧化酶(SOD、POD)活性、渗透调节物质(脯氨酸、可溶性蛋白和可溶性糖)质量分数逐渐上升,且耐盐品系‘2205’的抗氧化酶活性、渗透调节物质质量分数高于盐敏感品系‘1423’,而电导率低于盐敏感品系‘1423’。6个耐盐相关基因的表达量分析表明, Bna17410D和 Bna12880D基因的表达量在量耐盐与敏盐品系中呈现先上升后下降的趋势,其余均表现为一直上升的趋势。相关性分析表明, Bna00850D在两品系中与大部分耐盐相关指标的变化呈显著相关性,因此推测 Bna00850D可能为甘蓝型油菜耐碱性盐的候选基因。

In order to study the mechanism of the alkali salt tolerance in Brassica napus L., a salt-tolerant line‘2205’and a salt-sensitive line‘1423’were used as the experimental materials. The physiological indexes and the expression of salt tolerance related genes in seedlings of B.napus were measured under the artificial simulated alkaline salt stress(75 mmol/L NaHCO3), and the correlation analysis between them was used to predict the candidate genes. The results showed that the electrical conductivity, antioxidant enzymes(SOD and POD) activity, osmotic adjustment substances(proline, soluble protein and soluble sugar) in the leaves of seedlings increased with the prolongation of alkaline salt stress. The salt-tolerant line‘2205’had higher activities of antioxidant enzymes and contents of osmotic adjustment substances, and lower electrical conductivity than the salt-sensitive line‘1423’. The expression of Bna17410 D and Bna12880 D among six salt tolerance related genes increased firstly, and then decreased in both materials, while the expression of other genes showed a rising trend. The correlation analysis indicated that Bna00850 D expression was closely correlated with most indicators related to salt tolerance in both materials, therefore, Bna00850 D might be a candidate gene related to alkaline salt tolerance in B.napus.