中文摘要：

采用管栽方法研究了W1（滴水量7.5kg/管,滴水5次）、W2（滴水量11.0kg/管,滴水5次）、W3（滴水量17.6kg/管,滴水6次）、W4（滴水量21.8kg/管,滴水6次）4种滴水处理对0~100cm土层含水量、新大豆27号根系干重和长度及根活性在0~100cm土层分布、产量和水分利用效率的影响。结果表明,增加滴水量明显提高0~40cm土层土壤含水量下限,减少40~100cm土层贮水消耗量;增加结荚至成熟期根系总干重和根总长,主要是0~40cm土层根系干重和根长增加的结果,并减少80~100cm土层根干重和根长,明显增加根系伤流量和0~40cm土层根系活力;W4处理最大根干重和根长分别比W1处理增加60.29%,65.51%;W4处理比W1处理增产87.72%,W4处理水分利用效率比W1处理提高4.88%。增加滴水量,增加土层湿润深度,提高0~40cm土层含水量,促进花荚期0~40cm土层根系生长和延缓鼓粒期根系衰老是提高产量和水分利用效率的重要原因。

英文摘要：

The tube plant method was applied to study the effects of W1 （7.5 kg/tube,5 times）,W2 （1 1.0 kg/tube,5 times）,W3 （17.6 kg/tube,6 times）,W4 （21.8 kg/tube,6 times）four drip irrigation quan-tities treatments on water content of soil layer in 0-100 cm,root dry weight distribution and root length and root activity of Xindadou 27 in 0-100 cm soil layer ,yield and water use efficiency.The results showed that the increasing of irrigation amount obviously enhanced lower limit of water content in 0 -40 cm soil layer,decreased storage water consumption in 40 - 100 cm soil layer,increased the total amount of root from pod to mature stages and total root length,the main reason was that the root dry weight and root length were increased in 0-40 cm soil layer,decreased dry weight of roots and root length in 80-100cm soil layer,obviously increased the root flux activity and root activity in 0-40 cm soil layer;The maximum root dry weight and root length of W4 than W1 increased by 60.29%,65.5 1% respectively;The yield of W4 than W1 increased by 87.72%,water use efficiency of W4 than W1 increased by 4.88%.Increasing drip irri-gation amount,increasing the depth of soil humid,enhancing the water content in 0 -40 cm soil layer,at the flowering and poding period promoting root growth in 0-40 cm soil layer and delaying the roots senes-cence in seed filling were the most important reason of improving yield and water use efficiency.