EFFECT OF POTASSIUM IODIDE ON THE ASCORBIC ACID CONTENT AND GROWTH OF TOMATO PLANTS

Abstract
A series of to-mato plants grown in sand cultures was treated with KI in concs. that varied from 4 to 100 ppm. iodine; concs. of 4 ppm. did not reduce the growth of the plants as measured by their dry wts. Applications of 16 ppm. I or more, seriously injured the growth of the plants and also curtailed production of fruits. Injury was characterized by loss of green color of the plants, necrotic edges of lower leaves, followed by curling, and death. The injury moved progressively upward from branch to branch. Mn and Cu uptake of the treated plants was more pronounced than any of the other mineral constituents. All concs. of KI caused a marked decrease in the ascorbic acid content of the plants.