低温对玉米萌发期种子抗冷性的影响

Effect of Low Temperature on Coldresistance of Maize in Seed Germination

[目的]研究低温对玉米萌发期种子抗冷性的影响。[方法]探讨抗冷性不同的4个玉米品种种子在低温处理复温萌发过程中的表现。[结果]经过低温处理后,各品种玉米抗冷性均有一定的提高,冷敏感品系(辽单632和铁单18)5℃低温处理后相对电导率有较大幅度的波动,分别从7.5%、12.0%上升至41.0%、34.0%;郑单958、吉单415作为耐冷品系可溶性糖含量的增加幅度较大,为53.72%、70.26%。10℃下各品种MDA含量较27℃增加,但5℃下各品种MDA含量较27℃大幅度增加,与品种的耐低温性呈显著负相关(R=-0.7825**)。[结论]5℃低温处理的生理指标可以作为萌发期种子耐低温强弱的鉴定基础。

[Objective] The aim was to study the effect of low temperature on coldresistance of maize in seed germination.[Method] The performance of four maize varieties seeds in the process of low temperature treatment before rewarming germination were discussed.[Result] The coldresistances of all varieties were improved in a certain extent after low temperature treatments.Cold sensitive strain（Liaodan632 and Tiedan18） relative conductivity had a larger amplitude fluctuations with 5 ℃ low temperature treatment,respectively rised to 41%and 34% from 7.5% and 12%; Zhengdan 958 and Jidan 415 as the cold resistant strains,greatly increased the content of soluble sugar with 53.72%,70.26%.Comparing with 27 ℃,the MDA contents of all varieties at 5 ℃increased largely,and was more than 10 ℃,and the resistance of varieties was negatively correlated to low temperature（R =-0.782 5＊＊）.[Conclusion] The temperature of 5 ℃ could be used as identification of low temperature resistant strength during seed germination.