EXOGENOUS IAA AND BA ON ENATION CONSTITUTION OF MAIZE LEAVES AFFECTEDBY MAL-DE-RIO-CUARTO VIRUS IN ARGENTINA

In vascular bundles of maize plant leaves affected by Mal de Rio Cuart o virus, cell hyperplasias originating enations or galls on the abaxia l side of these organs are observed. The aim of this work is to analys e the enation histology after treatments with auxins (IAA) and cytokin ins (BA) exogenously applied during the period of enation formation. A uxins and cytokinins are the main hormones involved in the differentia tion of vascular tissues. In BA treatment, all hyperplasic tissues wer e differentiated in vascular tissues. Phloem differentiation showed a slight predominance when BA was applied alone. With IAA, hyperplasic t issues were differentiated in vascular tissues and parenchymatous cell s; xylem was predominant. The results of this work indicate thar IAA a nd BA showed different degrees of vascular tissue differentiation, as well as variations in the proportion of these tissues which constitute d the enation.