The Influence of Mineral Nutrition on the Organic Acids of the Tomato, Lycopersicum esculentum.

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Abstract
Chromatographic technique was employed in a study of the anazotic and amino acids of the tomato as affected by mineral nutrition. Formic, acetic, trans-aconitic, malic, citric, and possibly cisaconitic acids occur in the roots, leaves and fruits of the wilt-resistant Globe tomato. There are more acetic and trans-aconitic acids and less malic and citric acids in the roots than in the fruits, with intermediate amounts in the leaves. The gelatinous pulp of vine-ripened tomato fruits contains larger amounts of citric, acetic, formic and malic acids than the fruit wall. The effects of various ions on the concentrations of anazotic acids in tomato fruits does not seem to be correlated with specific ions, but is rather an inter-related effect. It is also dependent upon the concentrations of these ions. The predominately occurring amino acids of ripe tomato fruits are: glutamic, aspartic, trypto-phane, phenylalanine and histidine. The gelatinous pulp has a higher free amino acid content than the fruit wall. The effect of injection of various salt solutions into ripening fruits could not be correlated with the production of any particular organic acids. During ripening, the acetic acid decreases while citric acid increases up to some stage in ripening when it too starts to decrease. When various plant parts are considered, a low citric acid content seems to be frequently accompanied by a relatively higher acetic acid content.