Influence of Toxic Concentrations of Micro-Nutrient Elements in the Nutrient Medium on Vitamin Content of Turnips and Tomatoes

Abstract

The effects of high concns. of Mn, B, Zn, Mo, Cu, or Fe in the nutrient medium on the vitamin content of turnip greens and tomatoes grown in sand cultures were measured. The growth of both turnips and tomatoes was significantly retarded as the supply of any micro-nutrient element except Fe was increased and a greater concn. of that element was found in the vegetative plant parts. Significant changes occurred in the vitamin content of the plants. As the B supply to turnip plants was increased, a 60% increase in both niacin and thiamin in leaves occurred. Ascorbic acid values, however, were 20% less. A 35% increase in both niacin and riboflavin values was associated with increased Mn supply. In tomatoes a 60% increase in ascorbic acid content of the fruit was associated with relative high Cu supply in the nutrient soln.