盐胁迫对红心萝卜种子萌发及幼苗生长的影响
Effects of Salt Stress on Seed Germination and Seedling Growth of Raphanus sativus

为了探究不同浓度盐胁迫对红心萝卜种子萌发和幼苗生长的影响。用不同浓度的NaCl分别对红心萝卜种子和幼苗进行盐胁迫处理，并测定种子发芽率、发芽势、根长、下胚轴长、鲜质量、干质量及幼苗叶片叶绿素总量、游离脯氨酸、丙二醛质量分数等指标，结果表明，10 mmol·L-1 NaCl处理的发芽率、发芽势、下胚轴长、鲜质量最大，对照的根长、干质量最大，上述指标均随着NaCl处理浓度的增大而呈下降趋势；随着NaCl处理浓度升高和胁迫时间的延长，红心萝卜幼苗体内丙二醛和游离脯氨酸质量分数均随之增加，而叶绿素质量分数呈现先升后降的趋势。综合分析表明，低浓度(10 mmol·L-1)的NaCl处理对红心萝卜种子萌发有一定的促进作用，红心萝卜对低浓度盐胁迫具有一定的抗性。
The effects of salt stress on seed germination and seeding growth of germination of Raphanus sativus seeds under salt stress were studied. Different NaCl concentrations were treated on seeds and seedlings of Raphanus sativus,the seeds germination percentage,germination energy,root length,hypocotyls length,fresh mass ,dry mass ,total chlorophyll,molality of MDA and free proline of Raphanus sativus seeds and seedlings were measured. The results showed that the seeds germination,germination energy,hypocotyls length and the fresh mass of Raphanus sativus reached the highest at 10 mmol·L-1,the root length and dry mass of Raphanus sativus reached the highest in control. These indexes of seeds germination were significantly decreased respectively with the increasing of NaCl concentration. With the increases of concentration and stress time extending,the molality of MDA and free proline raised,while the mass fraction of total chlorophyll increased at first and then decreased. These results suggested that the seed germination of Raphanus sativus was promoted under 10 mmol·L-1 NaCl treatments,and Raphanus sativus has a certain degree of salt resistance.