| Effects of water and fertility spatial coupling on root fresh and dry weight and root activity were studied at different growing stages of winter wheat(Xiaoyan No.22).The experiment contains three kinds of wet ways(i.e.the overall soil wetting,the upper soil wetting and the lower soil wetting) and three kinds of fertilization ways(the overall soil fertilization,the upper soil fertilization and the lower soil fertilization).The results showed as follows :(1) Under different soil wetting treatment,fresh root weight of winter wheat with the treatment of overall soil wetting at flowering-filling stage was increased compared to the treatments of the upper and the lower soil wetting,with an average raise of 5.63% and 18.09%,respectively.There was no obvious difference of root activity between the treatments of overall soil wetting and the upper soil wetting,but the root activity of the treatments of overall soil wetting and the upper soil wetting were higher than the treatment of lower soil wetting;(2) Under different fertilization ways,the root fresh and dry weight and root activity of the upper and overall fertilization treatment was higher than that of the treatment of the lower fertilization at tillering and jointing stage.At flowering-filling stage,the reducing rate of root activity by the treatment of lower fertilization was lower than other two treatments.At maturing stage,there was a “premature senility” phenomenon of root activity in the treatment of soil lower fertilization;(3) From the coupling effect of soil wetting and fertilization mode from the changes of the winter wheat root activity,the combination treatment of overall soil wetting and the upper soil fertilization was the best,which can enhance the root fresh and dry weight and root activity and reduce residues of nitrogen and phosphorus in the soil. |