摘要： 试验于1999~2000年在中德合作项目北京试验基地进行。优化水氮系统全 生育期喷灌7次共318 mm，追肥2次共60 kg/hm²（纯氮）；传统水氮系统全 生育期畦灌4次共329mm，基追肥各1次共300 kg/hm²。试验结果表明，优化水氮系统较传统水氮系统小麦根系大，开花期综合根系年龄（IRSA）小，根系在30~60 cm 土层中分布较多；氮肥利用效率提高了4倍，但二者的产量和水分利用效率差异不大。

关键词: 水氮管理系统, 冬小麦, 根系

Abstract: At the Beijing experimental base of the Sino-German cooperative project, optimized and conventional irrigation fertilization systems were carried out in 1999-2000. Total 318 mm water with seven times and 60 kg/ha nitrogen with two t imes. were applied in the optimized system. Total 329 mm water with four irrgatio n times and 300 kg/ha nitrogen with base and top-dressing fertilization comprised the conventional system. The results were as follow. The root size of the optim ized system was larger and integrated root system age (IRSA) at flowering stage was younger than that of the conventional system, and the ratio of root in the 30-60 cm soil layer was also increased. There were no significant difference in both grain yield and water use efficiency between the two systems, although the opt imized system increa sed nitrogen use efficiency 4 times comparing with conventional one.

Key words: Waternitrogen system, Winter wheat, Root system