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以大田栽培的脐橙（Ｃｉｔｒｕｓ ｓｉｎｅｎｓｉｓ Ｏｓｂｅｃｋ）新梢为材料，用吸光计（Ｌｔｇｈｔａｂｓｏｒｂａｎｃｅ）反复测量了个别叶片内的叶绿素，有时也采集叶片样品在实验室内测定叶绿素和铁的含量。于叶片的扩展期内，叶绿素和铁的浓度的增减依赖于铁的吸收率，叶绿素的形成和叶片的生长量的相互比率。春梢叶片内叶绿素与铁的比率不断增长直至叶片充分展开时（５－６月份）为止，并延至１２月份仍能维持这一水平，秋梢叶片在１２月份达到同样比率。对成熟叶片当铁的含量＜５０ｐｐｍ时，叶绿素浓度对铁的回归在ｎ＝４６时，ｒ＝０．９０７。当成熟叶片内的铁＞５０ｐｐｍ时，它基本上含有相等浓度的叶绿素，表示其最大值约为３ｍｇ／ｇ（铁的重量）。未成熟叶片的位点图表明，大多数叶片和铁的浓度的关系来说具有低浓度的叶绿素。因而得出结论是每单位铁的叶绿素要到叶片成熟时才能达到最大浓度。 关于叶片内铁的浓度与萎黄程度或所测得的叶绿素的浓度之间的相互关系问题，至今未取得比较一致的意见（２、５、８、９、１０）。于分析前在新鲜叶片上除去表面的脏物，选样时依叶片的萎黄程度进行分类，不同类别间叶片内的铁的浓度出现交迭现象（８、１０）。同样，依据铁的含量对叶绿素浓度
In this experiment, chlorophyll extracted from field-grown Citrus sinensis Osbeck shoots was measured repeatedly with Ltghtabsorbance, and chlorophyll and iron contents were also measured in laboratory. The increase and decrease of the concentration of chlorophyll and iron during the extension of the leaf depends on the ratio of iron absorption, formation of chlorophyll and leaf growth. The ratio of chlorophyll to iron in spring shoot leaves increased until the leaves were fully expanded (May-June), and this level could be maintained until December. The autumn shoot leaves reached the same rate in December. For mature leaves, the regression of chlorophyll concentration for iron at <50 ppm iron at n = 46, r = 0.907. When the iron in mature leaves is> 50 ppm, it contains essentially the same concentration of chlorophyll, indicating a maximum of about 3 mg / g (iron weight). Site maps of immature leaves showed that chlorophyll was present at a low concentration for most leaf-iron concentrations. It is concluded that the chlorophyll per unit of iron does not reach its maximum concentration until the leaves mature. No consensus has been reached so far on the relationship between the concentration of iron in leaves and the degree of chlorosis or the concentration of chlorophyll measured (2,5,8,9,10). Before the analysis, the surface dirt was removed from the fresh leaves. The samples were classified according to the degree of chlorosis of the leaves. The iron concentrations in different types of leaves overlap (8,10). Again, depending on the iron content of the chlorophyll concentration