开花期干旱胁迫对不同基因型玉米生理特性和产量的影响

以耐旱性不同的3份玉米自交系为材料,在花期进行干旱胁迫处理，研究了耐旱系廊黄和昌7-2与旱敏感系TS141的花期耐旱性差异。结果表明，花期干旱胁迫后，3份玉米自交系的生长受到抑制，地上部和地下部鲜重以及株高下降，枯叶率升高，相对含水量下降,相对电导率升高,渗透调节剂脯氨酸、可溶性糖含量、保护酶SOD和POD活性增加。但是各个指标在不同自交系内变化的幅度不同。与旱敏感系TS141相比，耐旱系廊黄和昌7-2的生长受抑制程度较小；叶片相对含水量下降、相对电导率升高幅度较小；脯氨酸和可溶性糖含量、保护酶SOD和POD活性升高的幅度较大。干旱胁迫后，3份玉米自交系的开花时间间隔（ASI）延长，雄穗一级分枝数减少，产量降低。与旱敏感系TS141相比 ，耐旱系廊黄和昌7-2的ASI延长时间较短，雄穗一级分枝数减少的幅度较小，产量下降幅度较小，特别是单穗重和穗粒数表现更为明显。

Genotypic differences in response of physiological characteristics and grain yield of maize inbred lines to drought stress at flowering stag

Flowering stage is a critical period which influences the production of maize, and identifying traits related to drought tolerance of maize at flowering stage is of significance for drought-resistant breeding and germplasm improvement. In this study, we analyzed differences between drought-tolerant inbred lines (Langhuang and Chang7-2) and a drought-sensitive inbred line (TS141) of maize at flowering stage. The results are as follows. Drought inhibited maize growth, with leaf relative water content decreased whereas senesced leaf rate, relative conductivity rate, proline and soluble sugar content, and antioxidative activities increased. Compared with drought-sensitive line TS141, drought-tolerant lines Langhuang and Chang7-2 was slightly inhibited, with larger contents of leaf relative water, proline and soluble sugar, higher activities of antioxidative enzymes like SOD and POD, and lower relative electric conductivity. After drought stress, anthesis-silking-interval (ASI) of three inbred lines was prolonged, and tassel branch level and yield was reduced. Langhuang and Chang7-2 had shorter ASI extension and less reduction in tassel branch level and yield, especially weight per ear and kernel number per ear.