Biological response of winter wheat root system to fertilization depth

Effects of fertilization depth on root system distribution and senescence of winter wheat were studied on the Experimental Farm of Shanxi Agricultural University with a soil column culture. The results indicate that the root system distribution changes with fertilization depth. Fertilization in the depth of 50～100cm can lead to the increase of root weight, root vigor of sub-layer, flag leaf area and net photosynthesis ratio, meanwhile it keeps the activities of SOD and POD in root system at a high level. The content of MDA in wheat root system is decreased, and the senescence of wheat delays,the yield increases. The study also shows that super-deep (150cm) application of fertilizer has an inductive effect on root growing downwards also, but the total root weight and yield decreases sharply. It is suggested that the 50～100cm depth of fertilization could be used as an effective way to delay senescence and increase yield.