Abstract:In order to explore the response of rice dry matter accumulation to the water consumption process in the cold black soil region, the rice water consumption test was performed by evapotranspiration in the rice irrigation test station in Heilongjiang Province in 2017. The U7(76) uniform test was conducted to analyze the influence of water consumption in each growth stage on rice dry matter quality and dry matter accumulation process deeply. The results showed that the order (from large to small) of the determinant coefficient of water consumption in each stage on rice dry matter quality was bloom, coupling effect of jointing and booting with bloom, jointing and booting, coupling effect of bloom with milkripe, coupling effect of filled tillering with bloom, coupling effect of filled tillering with jointing and booting, and filled tillering. During the rice vegetative growth stages, through the time the dry matter accumulation entered into the rapid growth stage and the maximum of growth rate, the water consumption affected the dry matter accumulation quality indirectly. Each additional millimeter of water consumption in filled tillering would shorten the time the dry matter accumulation entered into the rapid growth stage by 0.459d;while each additional millimeter of water consumption in jointing and booting would speed up the dry matter accumulation in 0.0113g/d. During the reproductive growth stages, the direct effect of water consumption on the dry matter quality was greater than that of indirect effect. The effects of water consumption in each stage on rice yield and dry matter quality were the same, and the order from large to small was bloom, jointing and booting, filled tillering, milkripe, early tillering, and late tillering, while the water consumptions in jointing and booting stage and in bloom stage were negatively correlated with the economic coefficient. The result could provide theoretical basis for making the irrigation system in cold black soil region.
