CHLOROPHYLL CONTENTS OF THE FIRST LEAVES OF INTACT AND DETOPPED VICIA FABA L. PLANTS

In Vicia faba L. the chlorophyll contents, the fresh weight and the life span of the lower leaves of detopped plants were greatly increased as compared with intact plants. Similar results were produced in kinetin-treated intact plants. IAA treatment appeared to lack such an effect. It appears that most cytokinins are synthesized in roots. The roots, though extensive, appeared to have no nutrient metabolizing effect. ABA induced very little chlorosis in lower leaves of detopped plants. When these leaves were treated with mixtures of IAA, kinetin, GA3, and ABA with or without sugars, none of these treatments degraded chlorophyll. ABA, however, produced scorched leaves in some plants particularly in absence of kinetin. Increases in chlorophyll contents of intact plant sprayed with kinetin did not correspond to increases in leaf fresh weights.