几种水氮模式处理下冬小麦根系生长的差异

为了给冬小麦水氮管理提供理论依据,以京冬8号为试验材料,采用随机区组设计,研究了4种水氮模式(优化灌溉-传统施肥、传统水肥、秸秆还田-优化水肥、优化水肥、传统灌溉-优化施肥)处理下冬小麦根系生长的差异。结果表明,不同处理间冬小麦0~120 cm土层单位面积的根量有差异。与传统水肥相比,传统灌溉-优化施肥0~60 cm土层的根系长度有所减少,60~90和90~120 cm土层的根系长度分别增加14.62%和73.72%(P<0.05),总根量略增加;优化灌溉-传统施肥0~30 cm土层的根系长度明显增加(P<0.05),30~60、60~90和90~120 cm土层的根系长度分别减少3.52%、6.65%和18.21%,总根量增加;优化水肥和秸秆还田-优化水肥各土层的根量增加。与优化水肥相比,秸秆还田-优化水肥0~60 cm土层的根量有所增加,60~120 cm土层有所减少。各处理冬小麦根系密度随土层加深而递减的速度大小为优化灌溉-传统施肥>传统水肥>秸秆还田-优化水肥>优化水肥>传统灌溉-优化施肥。

Comparative Study of Root Growth and Distribution of Winter Wheat under Different Models of Irrigation and N Fertilization

To give information on management of irrigation and N fertilization of winter wheat,effects of four improved irrigation-fertilization models on root growth of winter wheat were investigated in a field experiment in a randomized complete block design.The results showed that,compared with winter wheat under traditional irrigation-traditional fertilization model,for winter wheat under traditional irrigation-optimized fertilization model,root length per unit area in the 0~60 cm soil layer decreased a little,root length per unit area in the 60~90 cm and 90~120 cm soil layer increased by 14.62% and 73.72% respectively(P< 0.05),and the total amount of root per unit area in the 0~120 cm soil layer increased a little.For winter wheat under optimized irrigation-traditional fertilization model,root length per unit area in the 0~30 cm soil layer increased significantly(P< 0.05),root length per unit area in the 30~60 cm,60~90 cm and 90~120 cm soil layer decreased by 3.52%,6.65% and 18.21%,and the total amount of root per unit area in the 0~120 cm soil layer increased.For winter wheat under the models of optimized irrigation-optimized fertilization and optimized irrigation-optimized fertilization with crop residues,root systems were well developed,and the amount of root in each soil layer increased.For winter wheat under optimized irrigation-optimized fertilization with crop residues,the amount of root in the 0~60 cm soil layer increased and that in the 60~120 cm soil layer decreased as compared with optimized irrigation-optimized fertilization.Under all the models,root length density and root weight density decreased with the increasing soil depth,and the rates of decline followed in order of optimized irrigation-traditional fertilization model > traditional irrigation-traditional fertilization model > optimized irrigation-optimized fertilization model with crop residues > optimized irrigation-optimized fertilization model > traditional irrigation-optimized fertilization model.