Abstract: Water resource deficiency is one of major problems in wheat (Triticum aestivum L.) production in North Plain of China. Irrigation plays an important role to obtain high grain yield and quality. Currently, many reports on the basis of different experiments and cultivars have suggested several irrigation regimes in wheat, but no consistent conclusion is available due to interactions between eco-environment and cultivar. In this study, two winter wheat cultivars were used under high-yielding cultivation in 2005–2007 growing seasons (with precipitations of 128.0 and 246.4 mm, respectively) to reveal the effects of irrigation amount on water consumption characteristics and dry matter accumulations in various organs. The results showed that the yield of treatment W2 (irrigated each 60 mm before sowing and at jointing) was the highest and the WUE of treatment W2 was significantly higher than that of other irrigation treatments in 2005–2006 and 2006–2007 wheat growing seasons. And when the precipitation was 246.4 mm from sowing to maturity in 2006–2007, the ratios of precipitation, irrigation amount and soil water amount to water consumption amount in treatment W2 were 47.32%, 23.04%, and 29.64%, respectively. Compared with in treatment W0, dry matter accumulation amount after anthesis and contribution of dry matter accumulation amount after anthesis to grains in irrigated treatments increased significantly with the highest of 8 241.59 kg ha^-1 and 84.18% respectively in W2. However over-irrigation significantly reduced the photosynthate and grain yield. Water consumption amount increased significantly with increasing irrigation amount, and the ratio of irrigation amount to water consumption amount increased too, but the ratio of precipitation to water consumption amount and the ratio of soil water amount to water consumption amount both decreased. The variation in the ratio of soil water amount to water consumption was larger than others. As far as grain yield, WUE and WUE of irrigation concerned in the experiment, the most appropriate treatment for recommendation was treatment W2, which was irrigated 60 mm before sowing and at jointing stage respectively. The ratio of soil water amount to water consumption amount and the WUE of irrigation were higher in treatment W1 than in treatment W2, and the grain yield in treatment W1 was 8 797.73 kg ha^-1 when the precipitation was 246.4 mm. The results can offer a useful reference for formulating water-saving cultivation techniques in the areas with different water resources.

Key words: Wheat, Water consumption characteristic, Dry matter accumulation and distribution, Grain yield