Chemistry and Biology Research Institute, Research Branch, Agriculture Canada, Ottawa, Ontario K1A OC6 Canada.
Plant Physiol. 1985 May;78(1):207-10. doi: 10.1104/pp.78.1.207.
Survival and cold hardiness declined gradually when cold-hardened Fredrick winter wheat (Triticum aestivum L.) was maintained at -6 degrees C for several weeks. Moisture content of crown and root tissue did not change significantly during this period. Uptake of O(2) and accumulation of (86)Rb by root tissue declined abruptly upon exposure to -6 degrees C, whereas a concomitant negative effect of freezing on these metabolic processes was not observed in crown tissue. Electron spin resonance spectroscopic analysis of microsomal membrane preparations from crown tissue revealed no evidence of gross changes in the physical properties of the bulk lipids even when seedlings were killed. The results provide biochemical evidence that seedling damage due to prolonged exposure to a mild freezing stress is due to disruption of key metabolic process in the root while cells within the crown remain viable.
当经过冷驯化的弗雷德里克冬小麦（Triticum aestivum L.）在-6°C 下保持数周时，其存活率和抗寒性逐渐下降。在此期间，冠部和根部组织的含水量没有明显变化。当暴露于-6°C 时，根部组织对 O(2)的摄取和 (86)Rb 的积累突然急剧下降，而在冠部组织中没有观察到冷冻对这些代谢过程的协同负面影响。来自冠组织的微粒体膜制剂的电子自旋共振光谱分析没有显示出即使在幼苗死亡时大块脂质的物理性质也没有明显变化的证据。结果提供了生化证据，表明由于长时间暴露于轻度冷冻胁迫而导致的幼苗损伤是由于根中的关键代谢过程中断，而冠部细胞仍然存活。
