versão impressa ISSN 0120-9965
FLOREZ, Víctor Julio e PEREIRA, Maria de Fátima D. Aleixo. Cytokinins are associated with flower development of Solidago x luteus plants under short days. Agron. colomb. [online]. 2008, vol.26, n.2, pp. 226-236. ISSN 0120-9965.
In Solidago x luteus (M.L. Greene) Brouillet and Semple (= x Solidaster hybridus, x S. luteus), a plant commercialized principally as cut flower, the process of floral induction is dependent on photoperiodic environmental conditions. In order to determine the action of cytokinins in this process, their presence was analyzed in photoperiodically contrasting conditions (long days (LD, 18 h) and short days (SD, 8 h)). In the first phase of the test, with the purpose to analyze the response of plants to phytohormones, weekly application of the following treatments were realized: 1) 10- M gibberellic acid (GA3), 4·10- M 6-benzylaminopurine (6-BA), and 10- M GA3 plus 4·10- M 6-BA; 2) 10- M GA3, 4·10- M kinetin (KI), and 10- M GA3 plus 4·10- M KI; and 3) 4·10- M KI. In the second phase, in order to know the endogenous concentration of hormones, plant extracts were analyzed by thin layer chromatography and quantified by enzyme linked immunosorbent assay (Elisa) previously separated by high determining the cytokinin activity in leafs and flower buds extracts of plants in the beginning of the treatments under LD and SD. It was showed that KI application accelerates the floral anthesis demonstrating the relation of endogenous cytokinins on the process of floral development. Finally, from the results obtained of the extracts submitted to Elisa, it is suggested the participation of cytokinins in the anthesis process of S. x luteus, where iPA (isopentenil adenosine) would have an important action being transported rapidly from the leaf to the flower bud in SD making faster process of anthesis floral observed in this photoperiod.
Palavras-chave : floral anthesis; phytohormones; gibberellic acid; 6-benzylaminopurine; kinetin; cytokinins; Elisa.