高寒地区冬小麦东农冬麦1号越冬前的生理生化特性

在北方寒地田间自然条件下，于越冬前不同时期(不同气温)分别对抗寒冬小麦品种东农冬麦1号(返青率大于85%)和非抗寒品种济麦22(返青率小于1%)的叶片、分蘖节和根取样，测定其与抗寒相关的一些生理生化指标。结果表明，东农冬麦1号的可溶性糖、可溶性蛋白、脯氨酸、叶绿素含量，以及超氧化物歧化酶(SOD)和过氧化物酶(POD)活性均高于济麦22；组织含水量、相对电导率均低于济麦22，说明东农冬麦1号的抗寒适应性强于济麦22。分蘖节储备抗寒物质的能力最强，是小麦安全越冬中起重要作用的器官。

Physiological and Biochemical Characteristics of Dongnongdongmai 1 before Wintering in High-Cold Area

Developing crop cold-resistance is an important breeding target in cold areas. Although simulated experiments have been conducted in house for selecting cold-resistant varieties, it is not clear the performances of varieties in the field, especially the step-by-step cold exercise in simulated experiments is hardly consistent with that in natural condition. Dongnongdongmai 1 is winter wheat (Triticum aestivum L.) cultivar that can bear low temperature and grow normally in Heilongjiang Province. To provide basic data for cold-resistant breeding and cultivation in wheat, several physiological and biochemical characteristics related to cold resistance were compared using Dongnongdongmai 1 (winter greening rate more than 85% in spring) and Jimai 22 (cold sensitive, winter greening rate less than 1% in spring). Both cultivars were planted in field condition and sampled at different dates (different temperatures) before wintering. The samples were separated into leaves, tillering nodes, and roots, respectively. The results showed that soluble sugars, soluble protein, proline, chlorophyll content, superoxide dismutase (SOD) activity, and peroxidase (POD) activity of Dongnongdongmai 1 were higher than those of Jimai 22. Water contents in different organs and relative electric conductivity of Dongnongdongmai 1 were lower than those of Jimai 22, indicating Dongnongdongmai 1 had higher adaptability to coldness than Jimai 22. Tillering node was the most important organ for safely wintering because it contained more substances related to cold-resistance than leaf and root.