玉米苗期抗旱性杂种优势表现研究

Study on the Heterosis of the Maize Drought Resistance in Seedling Stage

以43个玉米杂交组合及其相应亲本为材料,利用20%PEG-6000溶液在苗期模拟干旱胁迫,研究玉米苗期抗旱性的杂种优势表现,并探讨与亲本间的相关性。结果表明,12个组合存在正向超亲优势,18个组合具有正向中亲优势;以中单808作为对照,13个组合表现为正向对照优势。玉米杂交组合苗期抗旱性和对照优势与母本、父本、高值亲本、低值亲本及亲本均值间的相关性一致,均未到达显著水平,表明玉米杂交组合苗期抗旱性和对照优势与亲本间无明显的相关性,在育种实践中,不能根据亲本抗旱性来预测杂交种的抗旱性。

Forty-three maize hybrid combinations and their parents were used as materials. A simulate drought stress experiment was conducted using 20% PEG-6000 solution to study the heterosis performance of drought resistance at the seedling stage of maize, and to investigate the correlation with its parents. The results showed that, 12 combinations were shown to have positive super-parent advantage and 18 combinations had positive mid-parent advantage;13 combinations showed positive control heterosis compared with Zhongdan808. The drought resistance and control heterosis of the maize hybrid combination at the seedling stage were consistent with the maternal, male,high-value parent, low-value parent, and the mean of the parents, while none reached a significant level, indicating that there was no significant correlation between drought resistance and control heterosis of maize hybrids at seedling stage and their parents. The drought resistance of hybrids cannot be predicted simply based on the drought resistance of their parents in the practices of breeding.