Influência de 6-benzilaminopurina na morfogênese in vitro e na ocorrência de hiperidricidade no porta-enxerto VR043-43 (Vitis vinifera x Vitis rotundifolia).

• Autor(a) principal: Fernandes, Katryne Rates Goulart
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/4315
• topic: Morfogênese; Hiperidricidade; Videira; Morphogenesis; Hyperhydricity; Vine; CNPQ::CIENCIAS BIOLOGICAS::BOTANICA::FISIOLOGIA VEGETAL

The use of cytokinins in variable concentrations in in vitro plant tissue culture can induce the occurrence of structural and morphological changes, affecting the development and viability of the obtained material. The objective of this work was to characterize the influence of 6-benzylaminopurine (BAP) upon morphogenesis and mineral nutrition of grape rootstock VR043-43 (Vitis vinifera x Vitis rotundifolia). Plants obtained from nodal segments in hyperhydricity and callogenesis media, supplemented with BAP and without regulator were used. In callogenesis induction medium plants fresh and dry weight, macro and micronutrients contents, oxygen and carbon dioxide levels in the headspace were measured at 15, 30 and 45 days. In hyperhydricity induction medium, the levels of macro and micronutrients and structural analysis of the leaves obtained at 45 days. The results demonstrated that BAP organogenesis, promoting callogenesis and inhibited rhizogenesis, internodal elongation and leaf expansion. BAP also altered the relation of fresh and dry mass of shoot/ root system in detriment to shoots; altered the nutrition of the shoots, inducing callus formation, which acted as a mechanical barrier to elements absorption from the medium. There was higher accumulation of CO2 and consumption of O2 in callogenesis induction medium, in flasks with cytokinin, reflecting the elevated respiratory rate of the calluses, which prejudiced growth and development. In hyperhydricity induction medium, BAP promoted alterations in grape plants morphology, as multiple shoots, leaf lamina thickness and callusing in the base of the explants; and structural alterations, such as disorganization of the mesophyll parenchyma cells and stomata differentiated above the other epidermic cells. Leaves developed in medium with BAP did not accumulated starch, however their vascular bundles were most lignified and there was higher accumulation of green coloration compounds in reaction with toluidine blue concomitant with increasing of cytokinin concentration. We conclude that BAP promoted alterations in morphogenesis and development of the plants. The calluses formed in BAP-containing medium promoted alterations in nutrients absorption and translocation to shoots, as also in respiratory rates. There was hyperhydricity induction by BAP, which was evidenced by morphologic changes and structural alterations in leaves and in guard-cells shape and disposition.