Abstract: Based on the field experiment with two winter wheat varieties and three nitrogen(N) treatments,the spatial distribution characteristics of leaf N status and SPAD(Soil and Plant Analyzer Development) value,and their relationships were investigated.The results showed that leaf N content,accumulation leaf N content and SPAD value at different leaf position increased with increasing N supply,and the order of those values from high to low were the first leaf,the second leaf,the third leaf and the fourth leaf from the top.The SPAD value of the second leaf from the top was highest before flowering,while the order of the SPAD value from high to low was the first leaf,the second leaf,the third leaf,the fourth leaf from the top after flowering.There was significant correlation between SPAD value of the third and the second leaf from the top,and average N content and accumulation of leaf.

Key words: Wheat, Wheat, SPAD value, Spatial distribution, Nitrogen