A Study On The Regulation Mechanism Of Al-Induced Secretion With Organic Acids Metabolism In Rye

Al toxicity in plants is one of the major limitations to crops growth on acid soils. Exudation of organic acids is an important mechanism for plants to resist Al toxicity. Two secretion patterns have been proposed in plants. The mechanisms of organic acids in Pattern I has more documented while Pattern II has poor reported. Exudation of citrate and malate in Pattern II from roots is an important mechanism for rye to resist Al toxicity.The differences of Al-tolerance in wheat and rye were investigated in this paper. These results showed that Al-tolerance in rye was higher than in wheat. There was no difference in the activities of aconitase, citrate synthase, pyruvate kinase and hexokinase in wheat root apices and the activities of pyruvate kinase and hexokinase in rye root apices after exposure to Al solution for twelve hours. While the activity of aconitase in rye root apices was decreased significantly, the activity of citrate synthase in rye root apices was increased significantly. Therefore, rye was taken as study object for further study in present study. The main experimental results were as follows.