盐胁迫对红砂(Reaumuria soongorica)种子吸胀过程中生理特性的影响

以0%、0.5%、1.0%、1.5%、2.0%、2.5%、3.0%的NaCl和CaCl2溶液处理红砂(Reaumuria soongorica)种子,探讨了两种盐胁迫对种子吸胀过程中生理特性的影响及对种子的伤害程度。结果表明:红砂种子发芽率随两种盐胁迫的加剧极显著下降。种子丙二醛(MDA)含量在NaCl溶液胁迫后先下降后上升,在盐溶液浓度为1.0%时达到最小值,在2.5%处达到最大值;经不同浓度的CaCl2溶液胁迫后,MDA含量呈上升趋势,且均高于对照,最大值出现在3.0%处;种子内可溶性糖含量随NaCl和CaCl2溶液浓度的增大先下降后上升,分别在盐溶液浓度为1.0%和2.0%时达到最小值;种子过氧化氢酶(CAT)活性的变化较小;过氧化物酶(POD)活性随两种盐浓度的增加显著降低;超氧化物歧化酶(SOD)的活性随两种盐溶液浓度的增加先下降再上升又下降,但总体低于对照。经综合分析得出,CaCl2对红砂种子的伤害程度大于NaCl。

Effects of Salt Stress on Physiological Characteristics of Reaumuria soongorica Seeds during Imbibition

The effects of salt stress on physiological characteristics of Reaumuria soongorica seeds during imbibition and the damage of salts on seeds were discussed. Seven salts concentrations with 0%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0% of NaCl and CaCl₂ were designed in this study. The results showed that percent germination of Reaumuria soongorica seeds significantly decreased with increasing salts concentration. The content of malondialdehyde (MDA) decreased firstly and then increased as NaCl concentration increased, and reached the maximum and minimum value at salt densities of 1.0% and 2.5%. The content of MDA rose with increasing CaCl₂ concentration, and was significantly higher than that in controlled trial, and reached the maximum value at salt density 3.0%; The content of soluble sugar decreased firstly and then increased with increasing salt concentrations, and reached minimum at salt densities of 1.0% and 2.0%; The catalase (CAT) activity changed little as the two salts concentrations increased; The peroxidase (POD) activity significantly decreased with increased salts concentrations; The activities of superoxide dismutase (SOD) decreased firstly, then increased and decreased at last with the two salts concentrations increase, and was lower than that in controlled trial. The damage of CaCl₂ on Reaumuria soongorica seeds was bigger than NaCl.