水分胁迫对玉米萌芽期和苗期生长的影响

Effect of Water Stress on Growth of Maize in Germination and Seedling Stages

[目的]为了研究水分胁迫对玉米萌芽期和苗期生长的影响。[方法]用PEG高渗溶液模拟干旱条件,以抗旱性不同的玉米自交系为材料,研究了玉米萌芽期和苗期水分胁迫对其生长的影响及生理指标的变化与抗旱性的关系。[结果]各玉米自交系发芽率、叶片鲜干比明显下降,抗旱性强的自交系下降的幅度较小;根冠比、MDA含量和CAT、SOD酶活性均有一定程度升高,抗旱性强的自交系升高的幅度较大。萌芽期发芽率、苗期叶片鲜干比、根冠比、失水率、MDA含量及SOD和CAT酶活性与玉米抗旱性都有明显的相关性,可作为玉米抗旱性的鉴定指标。[结论]该研究为玉米早期抗旱育种提供了参考。

[Objective] The purpose of the research was to study the effect of water stress on growth of maize in germination and seedling stages. [Method] With maize inbred lines having different drought resistances as materials, the effect of water stress on growth of maize and the relationship between the changes of biological indexes and drought resistance in germination and seedling stages were studied by simulating drought condition with PEG hyperosmotic solution. [Result] The germination rate, the ratio of fresh weight to dry weight of leaf in the maize inbred lines were decreased obviously and that in the inbred lines with strong drought resistance were decreased to less extent. The rate of root to crown, MDA content, activities of CAT, SOD enzymes in the maize inbred lines were increased to some .extent and that in the inbred lines with strong drought resistance were to bigger extent. The germination rate in germination stage, fresh weight and dry weight ratio of leaf in seedling stage, rate of root to crown, water losing rate, MDA content and activities of CAT, SOD enzymes all had obvious relativities to drought resistances of maize and they could be used as identification indexes of drought resistances of maize. [Conclusion] The study supplied references for drought-resistant breeding in the early stages of maize.