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The test in March 2001 to October 2002, China Agricultural University, Beijing Changping Experiment Station Field experiments and systematic observation, early rice water demand water characteristics, root distribution under different irrigation treatments, physiological processes, yield formation and water use efficiency were discussed. The preliminary results show that: North China upland rice whole growth of water demand of 750 ~ 861mm, which upland rice 502 770 ~ 773mm, Handao297 750 ~ 861mm. Upland rice under different water treatments at different growth stages of water consumption and water consumption intensity most are concentrated in the planting to emergence and booting to heading stage. Upland rice root length and root weight maximum jointing to heading stage. Water stress will lead to 0 ~ 60cm soil root root weight and total root length decreased, deep root biomass in the total proportion of root biomass increased the slower root length density decreasing with soil depth, root to shoot ratio increased. Draw leaf photosynthetic rate and transpiration rate by of upland rice physiological factor analysis, non-linear relationship nonlinear relationship between photosynthetic rate and stomatal conductance, stomatal conductance and transpiration rate linearly related. Considering photosynthetic rate, transpiration rate and stomatal conductance of relations, stomatal conductance greater than the maximum photosynthetic required value, to take measures to increase the stomatal resistance suppression transpiration to promote photosynthesis is feasible to increase production and saves water. With the full irrigation w0 processing compared to 2001 several irrigation treatments before jointing of limited irrigation w2 processing was the best addition to irrigation, less water consumption, and roots in deep soil proportion increases its production, seed The rate of grains per spike, grain weight, agricultural water use efficiency decrease are the minimum input ratio and net income per hectare reduction are also the smallest. 2002 jointing are to limited irrigation w3 processing was the best. Water supply (irrigation, precipitation) under the conditions of 552 ~ 562mm, upland rice 502 yield is only 3.04 ~ 3.58 t · ha -1 , the production level of water use efficiency is only 0.55 ~~ 0.64 g · kg - 1 , the Handao297 yield of 2.55 ~ 2.97 t · ha -1 , yield level water use efficiency is only 0.46 to 0.53 g · kg -1 , while water supply (irrigation, precipitation) under the conditions of 727 ~ 933mm, upland rice 502 yield up to 5.34 ~ 5.66 t · ha -1 , water use efficiency of production levels up to 0.61 to 0.73 g · kg - 1 , Handao297 yield up to 4.71 ~ 5.29 t · ha -1 , the production level of water use efficiency of from 0.57 ~~ 0.65 g · kg -1 . Upland rice 502 five treatment regardless of the total root length, total root weight, yield, panicle length, seed rate, economic the coefficient or production structure, the average daily water use efficiency, and economic benefits are better than Handao297 five processing.
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