Water Consumption Characteristics and Water Use Efficiency of Flue-cured Tobacco Under Different Conditions of Irrigation

The experiments were carried out in lysimeters to study water consumption characteristics and water use efficiency of flue-cured tobacco under different conditions of irrigation. By comparing the T and the invalid E of the tobacco K326, it is concluded that in the period of root extending most of the irrigation water is used for the E, in the early vigorous period, plants with all of the treatments show a T higher than the E, in the late vigorous period and the maturity, this ratio remains at 50%. Based on measured data, it was shown that the amount of irrigation water in the vigorous period had the most important influence on the yield of the tobacco. The nonlinear equation of the yield and WUE is Y=-2531.3X(2)+6113.8X-624.49, R-2=0.7324; the equation of the yield and ET is Y=4E-0.7X(3)-0.0032X(2)+8.8458X-4806.7, suggesting that the WUE is not maximized at the highest yield of flue-cured tobacco. In the high-yield range, reducing irrigation appropriately could reach the harmonization of high production and water saving.