The Influence of Root Zone Temperature on the Growth and Contents of Phosphorus and Anthocyanin of Corn

Abstract

Abstract In a greenhouse experiment corn plants were grown in sand cultures using a complete nutrient solution in which only the P level varied. Root zone temperatures of 15°, 20°, and 25°C. were used in this experiment. In addition, 2 weeks after emergence, a number of plants were subjected to a sudden change in root zone temperature. The dry weight yield and the P content of the tops and the roots and the anthocyanin content of the tops were determined at 2 and 3 weeks. Low root zone temperature severely restricted the growth of young corn plants. High P levels never fully counteracted this harmful effect. It was likely that reduced P uptake at low root zone temperature was caused primarily by a depression in root growth, induced by the low root zone temperature. Anthocyanin synthesis was stimulated by both a low root zone temperature and a low P level in the nutrient solution indicating that purpling of corn is not necessarily an indication of P deficiency.