小麦叶片SPAD空间分布及其与氮素营养状况的关系

利用2个小麦品种在3个施氮水平下的田间试验数据，研究了小麦叶片氮素状况和SPAD（Soil and Plant Analyzer Development）值随叶位的空间分布特征，并对不同叶位叶片的氮素状况、SPAD值之间及其与叶片平均氮素状况之间的相关性进行分析。结果表明，随施氮量的增加，顶1叶、顶2叶、顶3叶、顶4叶的氮含量和氮积累量都呈增加趋势，并且基本呈顶1〉顶2〉顶3〉顶4的顺序；各叶位SPAD值呈两段式变化规律，开花前顶2叶SPAD值最大，开花后呈顶1〉顶2〉顶3〉顶4的趋势。顶3叶与顶2叶的SPAD值分别与叶片平均氮含量和氮积累量的相关关系最密切。

Spatial Distribution of Winter Wheat Leaf SPAD Value and its Relationship with Nitrogen Nutrition Status

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.