玉米根系活力杂种优势及其与光合特性的关系

对大田不同水分处理条件下玉米杂交种及其亲本在经济产量形成期的根系活力及其衰退的杂种优势进行了研究,并分析了根系活力与叶片光合特性之间的关系。结果表明,水分亏缺显著降低了玉米的根系活力;充分供水和水分亏缺条件下,玉米杂交种根系活力都具有显著的杂种优势;杂交玉米种根系活力衰退速率具有显著的负优势,抽雄后灌水能够显著降低玉米根系活力衰退速率。杂交玉米种在抽雄期各水分处理下的光合速率显著大于亲本;玉米根系活力与光合速率之间具有显著的正相关关系,随着根系活力的增高,玉米光合速率、气孔导度和蒸腾速率均增高。因此,杂交种较高的抗旱性是根冠共同作用的结果。在玉米育种和栽培中,要充分地考虑到根系对地上部生理活性的影响。

The use of heterosis was an important method to increase the yield of maize,but the studies of heterosis was centralized in the shoot of maize,whether the root activity has heterosis and the relationship of root activity and photosynthetic characteristics were not clear.The present field shelter-out rain experiment with hybrid maize and its parents under three soil water conditions was designed to study the heterosis on root activity and its declined properties and its relationship with photosynthetic chara...