【摘要】 分析了西峰站连续四年的作物发育状况和土壤湿度观测资料，得出了麦田蒸散耗水的基本规律。探讨了影响小麦生长发育和产量形成的关键需水期。提出作物耗水特性系数的概念，并以此评判冬小麦各发育期水分的供需状况，得出两年度冬小麦产量偏低的原因在于拔节—成熟期耗水特性系数明显偏小。建议及时灌孕穗水降低不孕小穗率，灌灌浆水提高小麦千粒重。更多还原

【Abstract】 Through analysis of soil water and phenological data of four successive years, regular pattern of winter wheat evapotranspiration was analyzed for the area of Xifeng, Gansu Province and the critical period of water requirement was determined during which water plays the most important role in the development and yield formation of the crop. A notion, water consumption characteristic coefficient, was presented and used for evaluating the status of water supply and demand in various developmental stages. Results showed that lower yield might be caused by a smaller coefficient during the period from elongation to ripening. Therefore booting water is needed for reduction of sterile spikelet and grout filling water for increase of grain weight.更多还原