两种独行菜种子萌发对不同浓度NaCl胁迫的响应

为探究腺独行菜（Lepidium apetalum Willd）和宽叶独行菜（Lepidium latifolium L.var.affine C.A.mey）种子萌发耐盐性特征，用玻璃培养皿采用暗发芽的方法，在恒温25℃种子培养箱中进行发芽试验，测定不同NaCl浓度（0，50，100，150，200，250，300 mmol·L^-1）胁迫下两种独行菜种子的发芽率、发芽势、日均发芽率、日相对发芽率和种子胚芽、胚根的长度。结果表明：在同等盐胁迫下，腺独行菜种子的发芽率、发芽势等各项指标均显著大于宽叶独行菜种子的。在不同盐胁迫下，随NaCl浓度增大，腺独行菜种子发芽率呈先增大后减小的特征，发芽势呈持续下降趋势；宽叶独行菜种子的发芽率和发芽势均呈显著下降特征，且NaCl浓度达到150 mmol·L^-1后，失去发芽能力；种子胚芽、胚根生长始终表现为腺独行菜优于宽叶独行菜。

Responses of Seed Germination of Two Lepidium Species to Different Concentrations of NaCl Stress

The purpose of this study was to investigate the characteristics of salt tolerance in the germination of Lepidium apetalum and Lepidium latifolium. A dark sprouting test was conducted with glass petri dishes in a seed incubator with a constant temperature of 25℃. The germination rate,the germination potential,the average daily germination rate,the daily relative germination rate,the length of the seed germ and embryo of two kinds of Lepidium L. seeds were determined under the salt stress of different NaCl concentrations (0,50,100,150,200,250,300 mmol·L^-1). The results showed that under the same salt stress,the germination rate,the germination potential,the average daily germination rate and the daily relative germination rate of L. apetalum seeds were significantly higher than that of L. latifolium. Under different salt stresses,the germination rate of L. apetalum seeds increased first and then decreased with the increase of salt concentration,and the germination potential showed a continuous downward tendency. The germination rate and germination potential of L. latifolium seeds decreased significantly with the increase of salt concentration. When the NaCl concentration reached 150 mmol·L^-1,the germination ability was completely lost. The growth of seed germ and embryo of L. apetalum were better than that of L. latifolium.