Studies on potassium nutrition of plants. II.—Some effects of potassium deficiency on the organic acids of leaves

Leaf organic acids of a series of plants have been determined by silica gel chromatography. Red beet and cabbage were grown in sand culture at six levels of potassium nutrition ranging from extreme deficiency to high potassium concentration. Potassium deficiency in cabbage, beet and potato leaves resulted in large increases of total organic acids, whereas there was a decrease in lettuce and no effect in Italian rye grass. Volatile organic acids of cabbage leaf were quantitatively minor components but at two extreme levels of potassium nutrition, they were present in the same relative proportions as total organic acid. Shikimic acid was tentatively identified in field‐grown rye grass (0.96% of dry weight).