单盐和混合盐胁迫对沙冬青种子萌发的影响

Effects of Single and Compound Salt Stress on Seed Germination of Ammopiptanthus mongolicus

采用恒温培养法研究了不同浓度的单盐（NaCl）和混合盐（NaCl和NANO3）溶液（5、10、15、20、25、30和35g/L）对沙冬青种子萌发的影响以及复蒸馏水后的恢复萌发率。结果表明：单盐和混合盐处理后的沙冬青种子萌发各项生理指标变化趋势保持一致;随盐溶液浓度的增加沙冬青种子的发芽率、发芽势、发芽指数、活力指数、胚根长、胚根鲜重和干重以及根冠比（R/T）均呈下降趋势,并且高浓度（≥10g/L）的盐溶液推迟了种子初始萌发时间;沙冬青种子初始萌发时间、休眠率和死亡率与两种盐浓度均呈极显著二次抛物线正相关关系（P〈0.001）;在0-10g/L盐溶液范围内,两种盐溶液均对沙冬青种子萌发起着轻微的促进作用,而盐浓度高于10g/L时,种子萌发受到一定程度抑制,盐浓度越高抑制作用越严重,综合比较可知单盐对沙冬青种子萌发的抑制作用高于混合盐溶液。解除胁迫条件,未萌发的沙冬青种子复蒸馏水后恢复萌发率均达到37.6%以上,而高浓度（35g/L）的两种盐处理下的种子恢复萌发率极低,表明一定范围的盐胁迫下沙冬青种子仍具有较高的萌发潜力,但盐浓度过高导致种子失活,并且种子萌发恢复率与处理盐浓度之间呈极显著负线性相关关系（P〈0.001）。

Seed germination of Ammopiptanthus mongolicus was measured under the treatments of single and compound salt mass concentrations（including 5,10,15,20,25,30 and 35g/L）with incubation method,and the restoration germination of seeds was observed.The results show that the physiological indicators of the seed germination under single salt are consistent with that under compound salt.For each treatment,the seed germination rate,germination potential,germination index,vital index,radicle length,seedling fresh weight,dry weight and the R/T rate of seedlings decrease with the increase of salt concentration,and higher salt concentration（≥10g/L）delays the initial germination time.Initial germination time,dormancy rate and death rate show remarkable positively quadratic parabola correlated with salinity（P〈0.001）;seed germination of Ammopiptanthus mongolicus is slightly improved by low salt concentration（≤10g/L）stress and inhibited by higher salt concentration（≥10g/L）.Comprehensive comparison shows that the inhibition effect of single salt on Ammopiptanthus mongolicus is higher than that of compound salt.When removing salt stress,some non-germinable Ammopiptanthus mongolicus seeds germinate after treating with distilled water and the recovery germination percentage is more than 37.6%,but the recovery germination percentage of the seeds under higher salt concentration（35g/L）is extremely lower,which indicates that Ammopiptanthus mongolicus seeds have a higher potential germination in a range of salt concentration and higher concentration salt will lead to thee inactivation of the seed.Moreover,the seed germination recovery germination is significantly negative linear correlation with salt concentration（P〈0.001）.