外源NO对NaCl胁迫下扁蓿豆种子萌发和幼苗生长的影响

为探寻调控扁蓿豆种子萌发期耐盐能力的途径,采用NO供体硝普钠(SNP)处理扁蓿豆种子,研究了盐胁迫下外源NO对扁蓿豆种子萌发和幼苗生长的影响。结果表明,150mmol/L的NaCl溶液显著抑制了扁蓿豆种子的萌发,显著降低了发芽率、发芽指数和幼苗长度。外源NO在一定程度上缓解了盐胁迫对扁蓿豆幼苗的发芽率、发芽指数、芽长和根长的影响,但也存在浓度效应,以0.05%处理为最佳。0.05%SNP+150mmol/L NaCl处理下的扁蓿豆种子发芽率为86%,显著高于单盐处理的(0%SNP+150mmol/L NaCl)(P0.05)。0.05%SNP+150mmol/L NaCl处理下的发芽率、芽长和根长与0mmol/L NaCl溶液处理差异不显著(P0.05),发芽指数显著高于后者(P0.05)。

Effects of exogenous NO on germination and seedling growth of Medicago ruthinica seeds under NaCl stress

In order to explore the pathway of Medicago ruthinica seeds to regulate the salt tolerance in ger-mination period,the influence of exogenous NO on seed germination and seedling growth of M.ruthinica were studied under NaCl stress.The result indicated that NaCl solution of 150 mmol/L inhibited seeds germination and reduced the germination rate,germination index and seedling length significantly.Exogenous NO could re-lieve the salt stress in some extent and the treatment of 0.5% mmol/L was the best.Under the treatment of 0.5% mmol/L NO＋150 mmol/L NaCl,the germination percentage and seedling length did not show significant difference from the treatment of 0 mmol/L NaCl （P 〉 0.05 ）,and germination index was significantly higher than control （P 〈0.05）.