冷型小麦对干旱和阴雨的双重适应性

Double adaptability of cold type wheat to drought and rainy weather

通过 10余年的研究 ,发现冠层温度持续偏低的冷型小麦具有广幅生态适应性 ,即在正常天气条件下 ,它的活力较好、代谢功能较强、具有较好的抗早衰能力 ,优于其它类型小麦 ;而在气象要素反差很大的干旱和连阴雨天气下 ,冷型小麦和暖型小麦、中间型小麦相比 ,不但冠层温度依然持续偏低 ,且在叶片功能期、叶绿素含量、可溶性蛋白质含量、过氧化氢酶活性、净光合速率和籽粒饱满指数等一系列重要内、外性状上仍能继续保持优势。这种对干旱和阴雨条件的双重适应性是冷型小麦一种宝贵的生物学品质 ,它有可能为小麦在多种气象生态条件下的高产、稳产打下较为坚实的生态生理基础 ,并能为优良品种的选育提出一个把冷温特征作为重要内容的较为新鲜的育种目标。

It has been discovered that there existed cold type wheat, warm type wheat and intermediate type wheat in natural world through observations and measurements of wheat canopy temperature (plant temperature) for over 10 years. Canopy temperature of cold type wheat was comparable to or always lower than that of check wheat from year to year; on the contrary, canopy temperature of warm type wheat was always higher than that of check wheat. Canopy temperature of intermediate type wheat had strikingly polymorphism, i.e., there were canopy temperature fluctuation, consistently lower canopy temperature like cold type wheat and consistently higher canopy temperature like warm type wheat in different years. The excellent adaptability of cold type wheat to a wide range of meteoro-ecological conditions has been found through further studies, i.e., under normal weather conditions, the activity of cold type wheat was stronger, metabolic function was better, senescence was lighter than those of other wheat types; On the other hand, under drought and rainy weather conditions with extremely differing unfavorable meteorological factors, cold type wheat with a low canopy temperature could continuously maintain those superiority to warm and intermediate wheat types in a series of important traits, such as leaf functional duration, chlorophyll content, soluble protein content, CAT activity, net photosynthesis rate and kernel plumpness index. The double adaptability of cold type wheat to drought and rainy weather, a very valuable biological trait, could provide solid ecological and physiologic bases to obtain high and stable yield in the various meteoro-ecological conditions and a novel breeding index to breed good varieties with a low wheat plant temperature.