【摘要】 在孕穗期（播种后65天）,玉米植株经10℃低温处理2天和5天后,雌穗超氧物歧化酶（SOD）活性下降,膜脂过氧化作用增强,对生物膜系统产生直接伤害,电解质外渗率增大,电镜下可观察到线粒体、细胞质膜破坏,胞间连丝膨大变形,甚至断裂;粗糙内质网卷曲成空心圆状,进而引起生理代谢紊乱,使可溶性糖和游离氨基酸含量增加,淀粉、蛋白质含量下降,阻碍雌穗发育,减少穗粒数,引起减产。更多还原

【Abstract】 Maize plants at booting stages (65 days after planting) were put under 10℃ for 2 -5 days in a growth chamber. The results indicated that chilling stress at this stage could cause decresed superoxide dismutase (SOD) activities and increased membrane lipid perioxidation in the female inflorecence of maize. Leading to direct injury on the biological membrane system and a sharp increment of electrolyte leakage in the tissue, under electronic microscape, it could be seen that the mitochondria and the protoplasmic membrane were damaged, the plasmodesmate swelled, deformed or even ruptured and the rough endoplasmic reticula curved into hollow spheres, these ultrastructural changes would lead to disordered metabolism, including increased soluble sugar and free amino acids. Decreased starch and protein contents. As the result, the development of the female inflorescence was hindered, the number of grains per ear reduced, and finaly, grain yield dicreased.更多还原