The effect of humic acid (Polymeric polyhydroxy acid 85 % w/w) on the utility of waste iron from Ereğli Iron and Steel Smelting Plant by peanut grown in acid, neutr and alkaline soils was investigated. Especially waste iron and humic acid applied together increased active iron, total iron and chlorophyll content of the plants grown in three different soils without affecting dry weight. L, a and b values of the leaves as a measure of leaf color and lightness were decreased by the humic acid and

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... aste iron treatments. That means leaf colors were became darker in these treatments. Negative correlations were found between chlorophyll content and L, a, b values of the leaves.