钙对低温胁迫下玉米种子萌发及幼苗生长的影响

Effects of calcium on maize seed germination and seedling growth under low temperature stress

【目的】研究外源钙对低温胁迫下玉米幼苗根系保护酶活性、玉米种子萌发及幼苗生长的影响,以期为提高玉米苗期抗寒性及玉米抗寒育种提供理论依据.【方法】以‘郑单958’玉米种子为试验材料,用不同浓度（0、5、10、15、20mmol/L）的CaCl2溶液处理低温胁迫下的玉米种子,研究低温胁迫下CaCl2对玉米种子萌发和幼苗生长的影响.【结果】低温明显抑制了玉米种子的萌发,影响了玉米苗高和根长的增加,抑制了脯氨酸和可溶性糖含量的累积,提高了丙二醛（MDA）含量.一定浓度的外源钙（5～15mmol/L）可提高低温胁迫下玉米种子的发芽率,提高玉米幼苗根系脯氨酸含量的积累,抑制丙二醛含量的增加.【结论】不同浓度钙对低温胁迫的缓解程度不同,适宜浓度的外源钙（5～15mmol/L）能明显改善低温胁迫对玉米幼苗生长的抑制作用,提高玉米幼苗对低温胁迫的适应性,增加玉米种子萌发和幼苗正常生长的能力.浓度为10mmol/L的CaCl2溶液处理对玉米低温胁迫的缓解效果最佳.

[Objective] The research aimed to study the effect of exogenous calcium on maize root pro- tective enzyme activity, seed germination and seedling growth under chilling stress and provide theoretical basis for improving cold-resistance at seedling stage and cold-resistance breeding. [Method] Zhengdan 958 maize seeds was used as the experiment material to study the effects of calcium at different concentrations （0,5,10,15 and 20 retool/L） on maize seed germination and seedling growth under low temperature stress. [Result] The results showed that low temperature obviously inhibited the germination of maize, impacted the increase of seedling height and root length,inhibited the accumulation and increased MDA content. Ex- ogenous calcium （5-15 mmol/L） was able to enhance the seed germination rate,improve the accumulation of proline and inhibit the increase of MDA content in roots of maize seedling under low temperature stress. [Conclusion] The exogenous calcium at the concentrations of 5415 mmol/L could significantly reduce the inhibiting mlnatlon effect of low temperature stress on growth of maize and seedling growth under low temperature stress. the concentration of 10 mmol/L. seedlings, improve the adaptability, seed ger- The best abating effect of CaC12 appeared at the concentration of 10 mmol/L.