The physiological assessment of the nutrient status of plants. II. The effect of the nutrient status of the plant with respect to phosphorus, sulphur, potassium, calcium, or boron on the pattern of leaf area response following the transfer to different nutrient solutions

Abstract

In a series of experiments, young subterranean clover plants were raised at several levels of phosphorus, sulphur, potassium, calcium, or boron respectively, and then transferred to complete nutrient solutions and to solutions without the previously varied element. Response patterns based on relative leaf area increases revealed quantitative relations with the nutrient status of the plants at transfer in the experiments with different phosphorus, potassium, or boron levels. In the sulphur experiment the response pattern indicated only the presence or absence of stress. In the calcium experiment the picture was somewhat obscured by premature death of leaves following collapse of the petioles. In a second series of experiments it was shown that the presence or absence of specific stresses could be determined from the patterns of leaf area response after transfer of plants to complete solutions and to solutions each without one of the five elements.