Effects of fertilizer application depth on senescence of flag leaf after anthesis and yield in dry land wheat

The effects of fertilizer application depth on the senescence of flag leaf after anthesis and yield in dry land wheat were studied in soil column.The results showed that fertilizer applying in relative depth (20~40 cm),the activity of superoxide dismatase (SOD) and catalase (CAT),and the soluble protein content in wheat flag leaf decreased slowly,and the content of malondiadehyde (MDA) in wheat flag leaf decreased,and delayed the senescence of flag leaf.From the total results,because of significant difference between treatment 2 (20~40 cm) and treatment 1 and treatment 4,and little significant difference between treatment 2 and treatment 3,the depth (20~40 cm) of fertilizer application could be as index for delaying senescence,and the basis for taking administration programme,and gainning high yield and high efficiency.