低温胁迫对不同基因型玉米幼苗的影响

Effects of Low Temperature Stress on Seedlings of Different Genotypes Maize

以不同基因型玉米品种郑单958、京科968、先玉335、农大108、京农科728和正大615为试验材料,在玉米苗期进行低温胁迫,分别在0、2、4 d采集玉米植株样品进行测定,通过比较玉米幼苗株高、株重、丙二醛含量、脯氨酸含量以及可溶性糖含量的变化,研究低温对不同基因型玉米幼苗的影响。结果表明,在常温(25℃)和低温胁迫(5℃)的培养条件下,京科968和京农科728的株高均高于先玉335、郑单958、正大615和农大108,其中京科968的株高显著高于其他基因型玉米幼苗。5℃低温胁迫条件下,京科968和京农科728的株重显著高于先玉335、郑单958、正大615和农大108。低温胁迫(5℃)0、2和4 d条件下,京科968和京农科728种子的丙二醛(MDA)含量和脯氨酸均低于其他基因型玉米幼苗,可溶性糖含量在不同基因型玉米幼苗间呈相反趋势,在低温胁迫4 d后优势更明显。在低温胁迫下,京科968、京农科728表现出较强的耐冷性,该研究为解决目前玉米生产中遇到的低温冷害问题提供理论参考依据。

Six widely planted maize varieties in China, including Jingke 968(JK968), Jingnongke 728(JNK728), Xianyu 335(XY335), Zhengdan 958(ZD958), Zhengda 615(ZD615) and Nongda 108(ND108) were used as materials. Low temperature stress was used in maize seedling stage. Plant samples were collected at 0, 2 and 4 d for determination. Experiment was conducted to study the effects of low temperature stress on the plant height, plant weight, proline content, malondialdehyde(MDA), soluble sugar content of maize seedlings. Under normal temperature(25 ℃) and low temperature stress(5 ℃), the plant height of JK968 and JNK728 were higher than those of XY335, ZD958, ZD619 and ND108. And JK 968 and JNK728 were significantly higher than those of other genotypes of maize seedlings. Plant weights of JK968 and JNK728 were significantly higher than those of XY335, ZD958, ZD615 and ND108 under 5 ℃. MDA and proline contents of JK968 and JNK728 seeds were lower than those of other genotypes of maize seedlings under low temperature stress for 0, 2 and 4 d. Soluble sugar content showed the opposite trend among different genotypes of maize seedlings, and the advantage was more obvious after 4 d of low temperature stress. JK968 and JNK728 showed the best cold tolerance under low temperature stress. The research results provided theoretical basis for solving the cold injury problems encountered in maize production.