| According to nonstandard distribution of rainfall resource as well as the shortage of agricultural water resource in eastern Hebei, Distribution properties of rainfall period, water-demanding rule of main crops (winter wheat, film-covering peanut, spring corn and summer corn) and effects of agronomic measures on water utilization efficiency of winter wheat were studied on the basis of the double win of water-saving and higher yield.1. In accordance with the water profit and loss of four crops during the full growth stage, all four crops expressed rather amount of water loss or profit, the water loss amount of winter wheat was 308.8mm, while the data of water profit were 101.4mm, 126.7mm, 130.9mm in film-covering peanut, spring corn and summer corn, respectively.2. In terms of the distribution of water profit and loss in different stages in four crops, all stages of winter wheat appeared water loss in different degrees, especially, from over-wintering to elongation stage, from elongation to booting state, and from booting to grain filling stage. Therefore, it was important to fight a drought and irrigate from over-wintering to grain filling stage. Meanwhile, some water loss also presented during such stages as seeding to over-wintering and grain filling to maturing. However, it was unnecessary to irrigate from seeding to over-wintering stage in which winter wheat had the ability of drought-tolerance. Whether irrigation during grain filling to maturing stage would be carried out depended on the local water resource and production benefit.The water of film-covering peanut could be balanced both from seeding to flowering and from fruit-grain filling to maturing. Although it would be water loss to some extent from flowering to podding, it was still unnecessary to irrigate because it was difficult to supply water under the film. Therefore, it would better irrigate enough before seeding. Nevertheless, the water would be profit from podding to pod filling stage, pay attention to draining otherwise it would affect the pod development for much water.Water would be balanced basically from elongation to heading stage while some water loss might be appeared from seedling to elongation stage. It didn't matter since corn possessed the stronger drought-resistance at this stage, on the contrary, appropriate drought would contribute to root-system development. It was form heading to maturing stage that the soil would compensate water because it was in the rain season.As for summer corn, water would be profit from seeding to heading stage while water would be balanced from heading to grain filling. Just from grain filling to maturing did soil water lack, but it would be made up by more soil water at the early stage. Therefore, it would be unnecessary to irrigate the whole stage for summer corn.3. The water utilizing efficiency of different varieties of winter wheat varied very much. The effect of number of irrigation on water efficiency altered in different fertilization. The effect of several watering was higher than that of few watering, however, there were no obvious differences between two-, three- and four-time watering in spring. The production efficiency of irrigating water would be reduced with the increasing number of irrigation and total irrigation volume. The volume, strength and coefficient of water-consuming in the field increased with the total irrigation water volume under the different irrigation treatment. Irrigation by stages would contribute to improve yield and water utilizing efficiency when the total irrigation volume didn't change.Sum up, the best project of irrigation of winter wheat in spring in eastern Hebei would irrigate twice, at stage of elongation and from booting to grain filling, respectively, 600 m3/hm2 each.
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