水分胁迫下不同抗旱类型品种对氮素营养反应的比较研究

实验结果表明,小麦受到水分胁迫时,游离脯氨酸大量积累,胁迫缓慢加重时,渗透调节能力增强,适当的氮素营养,可增强渗透调节作用,有助于干旱下维持膨压,提高NR酶活性和净光合速率。水地型品种对水分和氮素营养都较敏感,叶片水势、饱和渗透势、NR酶活性、游离脯氨酸含量的变化都较旱地型品种大,旱地型品种在受旱时水分状况较稳定,生理代谢变化幅度较小,但两类旱地品种对氮素营养的反应不同。旱肥型较旱薄型敏感。水分胁迫下,水地型品种渗透势下降较多,渗透调节幅度较大,是对逆境更敏感或实际受到的胁迫较重的表现。

COMPARATIVE STUDY ON RESPONSES TO NITROGEN NUTRIENT OF DIFFERENT DROUGHT RESISTANCE TYPES OF WHEAT UNDER WATER STRESSES

Three ecotypes of winter wheat (2 dryland types and 1 irrigated ty-pe)with different nitrogen nutrient and water supplied levels had beenstudied in pot experiment during 1987-1988. The results indicated that,as the water stress developted slowly in wheat plant, the free prolineacid and osmotic adjustment capability were increased markedly. App- lication an appropriate amount of nitrogen can strengthen the effectof osmotic adjustment, and thus advance to maintain the leaf turgorat certain level, and also raise the NRase activity and net photosyn-thetic rate. The irrigated land variety type are more susceptible towater and nitrogen deficit, and the dryland high-fertility type are moresusceptible to nitrogen nutrient than the dryland low-fertility one.