不同基因型玉米萌芽期的抗旱性研究

对4个玉米杂交种辽单24、丹413、沈丹16、沈农87进行了萌芽期的抗旱性研究。结果表明水分胁迫降低了杂交种的发芽势和发芽率,阻碍了胚根和胚芽的生长,也降低了叶片的蒸腾速率和光合速率。但不同杂交种在抗旱性上存在明显差异,在水分胁迫下,抗旱性强的杂交种仍然保持较高的发芽势和发芽率。水分胁迫下,玉米种子的吸水速率减小,但吸水速率与抗旱性间相关性不明显。各品种在20%PEG水分胁迫处理下的萌动吸水伤害率间差异明显,可以作为一个抗旱鉴定指标。研究表明,利用室内高渗溶液萌发法通过对玉米萌芽期抗旱性高度相关的性状的测定得出的萌芽期抗旱性鉴定结果与田间直接鉴定的结果基本相符,说明室内高渗溶液萌发法是鉴定玉米萌芽期抗旱性的一种快速、简便、准确的方法。

Drought Resistance of Different Maize Varieties in Germination Stage

The studies on drought tolerance of four genotype in seedling emergence stage show that the viability and percentage of germination,growth rate of seedling and root,photosynthetic rate and transpire rate were decreased under water stress. There were obvious drought resistance differences among the hybrid.The higher drought resistance hybrids kept high viability and percentage of germination,photosynthetic rate and transpire rate under water stress while the lower drought resistance hybrids were decreased seriously.The water absorbing rate of seeds was decreased under water stress.But its correlation with drought resistance is not significant.The water absorbing injury rate of germinating seeds under 20%PEG water stress among varieties has significant diversity which can be a effective index of drought resistance identification.The research indicates that the result of lab drought resistance by appraising those characters being trusted in high osmotic solution has high correlation with that of field directness appraisal.It suggests that the method of lab germination test in high osmotic solution is a quick,simple and exact method to appraise drought resistance at germination stage.