Modification of cadmium toxicity in pea seedlings by kinetin

Abstract

The effect of foliar application of kinetin on the growth and some physiological processes of pea plants growing in soil supplemented with 25 or 50µM Cd were studied. Cadmium treatment inhibited the growth rate, chlorophyll (Chl) content, net photosynthesis (P_N), content of soluble sugars and free amino acids of either shoots or roots. The application of kinetin (kin) enhanced the growth rate, Chl content, P_N, soluble sugars and free amino acids content of shoots and roots; dark respiration rate (R_D), contents of soluble protein and proline were increased by cadmium treatment. The addition of kinetin to Cd-stressed plant reduced R_D, soluble protein and proline content. Considerable variations in the content of Na⁺, K⁺, Ca²⁺ and Mg²⁺ were induced by Cd-treatments. Foliar application of kinetin exhibited a favorable effect on the accumulation of some ions and antagonized or ameliorated the inhibitory effect of Cd stress on some others.