高温胁迫对玉米形态、叶片结构及其产量的影响

以郑单958(ZD958)和先玉335(XY335)为试验材料,模拟增温处理,探索营养生长和生殖生长并进时期(第9片叶完全展开至抽雄期)高温处理对玉米形态、叶片结构及其产量的影响。结果表明,高温处理后ZD958和XY335的产量分别比对照降低了11.14%和25.40%。高温处理促进株高增长,促使茎粗变细,降低叶面积指数、干物质重、成熟叶片和幼嫩叶片的比叶重。随生育进程,XY335的株高、茎粗、叶面积指数、干物质重和ZD958的干物质重变化幅度逐渐增大,2个玉米品种的幼嫩叶片比叶重降低幅度均要大于成熟叶片比叶重。叶片厚度和上下表皮细胞厚度变薄,叶绿体膜结构被破坏,抑制光合作用及光合产物的输出。对高温胁迫的敏感性而言,XY335大于ZD958,ZD958成熟叶大于幼嫩叶,XY335幼嫩叶大于成熟叶。

Effect of High Temperature Stress on Morphology, Leaf Structure and Grain Yield of Maize

A field experiment of artificial warming was conducted on two maize cultivars ZD958 and XY335 from 9th leaf stage to tasseling stage, aiming to explore the effects of high temperature on the morphology, leaf structure and grain yield of maize. Under high temperature stress, the grain yields of ZD958 and XY335 respectively decreased by 11.14% and 25.40% compared with the control. High temperature treatment promoted plant height higher, caused stems thinner, and reduced leaf area index, dry matter weight, and the specific leaf weight of mature leaves and young leaves in both maize varieties. And these changes in XY335 and the dry matter weight on ZD958 gradually increased with plants growing. The specific leaf weight of young leaves decreased more than that of mature leaves in two maize cultivars. Moreover, plant leaves, the upper and lower epidermal cells became thinner, chloroplast membrane structure was destroyed and then inhibited photosynthesis and photosynthetic output. As for the high temperature sensitivity of plants, XY335 was greater than ZD958, the mature leaves were more sensitive than the young leaves in ZD958, while the mature leaves were less sensitive than the young leaves in XY335.