Influência do acondicionamento, antioxidantes, auxinas e seus cofatores no enraizamento de miniestacas de clones de Eucalyptus grandis x E. urophylla

• Autor(a) principal: Goulart, Patrícia Bueno
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3174
• topic: Rizogênese; Reguladores de crescimento; Mini-estaquia; Propagação vegetativa; Silvicultura; Clonagem; Antioxidantes; Rhizogenesis; Growth regulators; Minicuttings; Vegetative propagation; Eucalyptus; Cloning; Antioxidants; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::SILVICULTURA

The purpose of this study was to evaluate the influence of storage, antioxidants, auxins and their cofactors on the resulting rooting, as well as rooting rhizogenesis patterns in minicuttings of four Eucalyptus grandis x E. urophylla clones. The samples were collected from a clonal hydroponic minigarden. Regarding the evaluated characteristics, it was observed that the clones responded more effectively to the applications of IBA growth regulator than to the ANA applications, with the IBA doses ranging from 500 and 2,000 mg L-1 being more effective on the examined clones. As for the treatment of the minicuttings using cofactors associated to IBA, it was observed that chlorogenic acid and hydroquinone improved the rooting and survival indices in three clones; phenylalanine and phloroglucinol improved said indices in two of the clones; while only caffeic acid, tryptophane and especially proline improved these responses in all examined clones. The responses to the application of antioxidants varied: the best plant rooting and survival indices were obtained with the use of ascorbic acid and activated carbon with only one clone; whereas PVP showed to be effective with all the examined clones. The best technique was to plant the minicuttings immediately upon their harvest from a clonal minigarden, since it provided the best rooting and survival indices with all four clones, and avoided a negative impact on the propagators due to storage, even when stored for only a short period of time. As for the means used to store the minicuttings, it was observed that the best results were obtained by conditioning the minicuttings in a vertical position with a composite of vermiculite and PVP, possibly due to the specific use of PVP with certain types of clone. The obtained results allow the conclusion that there s a strong correlation between the genotypic differences of the analyzed materials and the plants rooting and their survival success as a response to the use of growth regulators, cofactors and antioxidants on different clones. Thanks to this study new information was brought about regarding the rhizogenesis patterns of minicuttings of the examined clones. It was observed the presence of an endogenous origin of the root primordia as well as the formation and proliferation of a disorganized mass of cells (calli) in minicuttings of up to 12 days old, with one H1 clone standing out from the others for having presented root primordia on or after the eighth day after the minicuttings were planted.