夏玉米的干旱适应性及其生理机制的研究

1987～1988年,分别在大田和遮雨塑料棚条件下,测定并分析了三个抗性不同的夏玉米杂交种与干旱适应性有关的一些生理特性.结果表明,夏玉米杂交种受旱后,对干旱均表现出了程度不同的适应性;高抗杂交种以较强的根系活力、气孔调节能力和广泛的水分适应性体现其抗旱性,在耐旱性上则主要表现为受害后叶绿素含量较稳定,膜损伤小,游离脯氨酸积累量大.二者综合作用的结果、使其抗旱系数大,经济产量高.此外,还对夏玉米抗旱机理以及气孔扩散阻力、游离脯氨酸积累与抗旱性的关系进行了初步探讨.

A Study on Drought Adaptability and Its Physiological Mechanism of Summer Maize

Drought adaptability and physiological characteristics at different growth periods of 3 different maize hybrids were tested and analyzed under the conditions of field and plastic shed from 1987 to 1988. The results showed that the adaptable degrees to the drought were all different when summer maize hybrids were drought. The hybrids with high drought resistance had higher root activities, better stomatal adjustment and better adaptability to water contents. Physiologically, the drought tolerance was mainly due to the steady content of chlorophyll, less injured cell membrane and greater amounts of free proline accumulation. As a synthesized result above two functions, the drought tolerant hybrid possessed a higher coefficient of drought resistance and produced more yield. Furthermore, a preliminary study on the mechanism of drought resistance and the relationship between the drought resistance and the diffusion activity of stomata and the free proline accumulation was discussed