不同供水条件对冬小麦根系分布、产量及水分利用效率的影响

Impacts of different water supplied conditions on root distribution,yield and water utilization efficiency of winter wheat

通过中科院栾城农业生态试验站3种不同降水年型的田间灌水试验，研究了不同供水条件对冬小麦根系分布、产量及水分利用效率的影响，旨在为华北地区冬小麦建立优化灌溉制度，提高水分利用效率，达到节水增产目的提供理论依据。试验结果表明，冬小麦根系主要集中分布在80cm以上土层，随土层深度的增加，根长密度星指数下降；综合分析根系对不同土层的水分吸收、作物耗水组成及产量、水分利用效率与总耗水的关系，提出华北地区冬小麦最佳灌水方式是：丰水年灌0水、平水年灌1水（拔节水）、枯水年灌2水（拔节水和抽穗水），次灌水量60～75mm，具有明显的节水增产效益。

Field experiments were conducted at Luancheng Station, Chinese Academy of Sciences in different precipitation years. The impacts of water supplied conditions on root distribution, yield and water utilization efficiency （WUE） of winter wheat under different irrigation treatments were analyzed in order to supply a basis for optimum irrigation mode which could increase the yield and improve water utilization efficiency. The results indicated that most roots were concentrated in the upper 80 cm soil layer, and the density of roots declined exponentially downward with the increase of the soil layer depth. Considering water consumption in different soil layers, and the relationships among yield, water utilization efficiency and total water consumption, the optimal irrigation mode in North China plain was put forward, i. e. , no irrigation in rain-full years, one time irrigation at jointing stage in normal years and two times at jointing stage and booting stage in dry years with the suitable water quota of 60 to 75 mm each time, which not only increased the winter wheat yield, but also benefited to using the deep soil water and improving the water utilization efficiency.