花棒种子萌发对NaCl及聚乙二醇胁迫的响应

本研究采用NaCl及聚乙二醇(Polyethylene glycol，PEG-6000)分别模拟盐胁迫及干旱胁迫的方法，测定花棒(Hedysarum scoparium Fisch. et Mey.)种子的逐日萌发率、发芽率、发芽势、发芽指数和活力指数，确定其在逆境条件下的萌发阈值。结果表明：随着处理浓度升高，花棒种子各项萌发指标均呈下降趋势；当NaCl浓度为0.2%时，其发芽率、发芽指数为对照的87.1%和54.8%；当NaCl浓度高于0.2%时，各项指标则随浓度升高而显著下降；当PEG-6000浓度为15%时，其发芽率、发芽指数分别为对照的91.6%和55.4%；当PEG-6000浓度高于15%时，各项萌发指标显著降低。综上所述，花棒种子NaCl胁迫的正常萌发阈值为0.2%，PEG胁迫的正常萌发阈值为15%，花棒种子萌发期能忍耐低盐分、中度干旱胁迫。

Response of Seed Germination of Hedysarum scoparium to NaCl and Polyethylene Glycol Stress

In this study,using NaCl and PEG-6000 to simulate salinity and drought stress conditions on seeds respectively,and the daily germination rate,germination rate,germination potential,germination index and vigor index of seeds were measured,determine its germination threshold under stress conditions. The results showed that the indices mentioned above decreased under stressed conditions. When the NaCl concentration was 0.2%,the germination rate and the germination index of seeds account for the 87.1% and 54.8% of that of the control group;when the solution concentration was higher than 0.2%,the indexes decreased dramatically with the increase in concentration. When PEG-6000 concentration was 15%,the germination rate and the germination index of seeds were 91.6% and 55.4% of that of the control. However,when the PEG concentration was higher than15%,the seed indices decreased significantly compared with the control group. In conclusion,the NaCl solution concentration of 0.2% was the most suitable concentration limit for normal H. scoparium seed germination. PEG-6000 of 15% was the most suitable concentration limit for seed normal germination,H. scoparium seed germination period can tolerate low salinity and moderate drought stress.