豌豆种子萌发及幼苗生长对NaCl胁迫的响应

Response of germination and seedling growth of pea seeds to NaCl stress

以"陇豌一号"和"S4008"2个豌豆品种为材料,利用不同浓度的NaCl溶液处理种子进行发芽实验,研究豌豆种子萌发及幼苗生长对NaCl胁迫的响应。结果表明:10 mmol·L–1 NaCl胁迫可促进种子萌发,2个豌豆品种的发芽率、发芽势、胚芽和胚根长、幼苗鲜重和干重、相对含水率、叶绿素含量均显著高于对照(P<0.05);25 mmol·L–1 NaCl处理略高于对照,但差异不显著;发芽指数总体随着盐浓度增高而降低,10、25 mmol·L–1处理与对照差异不显著;高浓度NaCl(50、100、200 mmol·L–1)则显著抑制了发芽率、发芽势、胚芽和胚根长、幼苗鲜重和干重、相对含水率以及叶绿素含量(P<0.05),且胚根下降趋势大于胚芽;极高浓度NaCl(300 mmol·L–1)胁迫下种子基本不发芽。细胞膜透性随着盐浓度增加显著上升(P<0.05);丙二醛含量随NaCl浓度的增加先升高后降低,100 mmol·L–1处理达到最大值;而脯氨酸含量则先降低后升高(P<0.05),25 mmol·L–1处理达到最小值。胚根是对盐分胁迫较敏感的部位,S4008抗盐能力>陇豌一号。

In this thesis, two pea varieties, ＂Longwan 1＂ and ＂S4008＂ have been used as the experiment materials, and under different concentrations of NaCl stress, response of germination and seedling growth of pea seeds were investigated. The results show that 10 mmol·L–1 NaCl could promote seed germination, and 2 varieties of pea germination rate, germination, plumule and radicle length, seedling fresh weight and dry weight, relative water content, chlorophyll content were significantly higher than controls（P〈0.05）. 25 mmol·L–1 NaCl treatment was slightly higher than the control, but the difference was not significant; germination index decreased with increasing salt concentration, 10, 25 mmol·L–1 treatment and the control were not significant. High concentration of NaCl（50, 100, 200 mmol·L–1） significantly inhibited the germination rate, germination, plumule and radicle length, seedling fresh weight and dry weight, relative water content and chlorophyll content（P〈0.05）, and the radicle showed greater decreasing trend than germ. Extremely high concentration NaCl（300 mmol·L–1） stress could not germinate practically. The cell membrane permeability increased with the salt concentration increased significantly（P〈0.05）; malondialdehyde increased with the concentration of NaCl first and then decreased. The treatment of 100 mmol·L–1 reached a maximum value; and the proline content was increased firstly and then decreased（P〈0.05）. 25 mmol·L–1 reached the minimum value. The radicle is a more sensitive part under salt stress. Two pea varieties show salt resistant ability in the order of： S4008〉Longwan 1.