ROOTING OF Araucaria angustifolia: TYPES OF CUTTINGS AND STOCK PLANTS SEX

ABSTRACT Araucaria angustifolia is native to Brazil and has always raised economic interest for the qualities of its timber and as a supplier of pine nuts for human consumption. The scarce germination viability of the stored seeds and the possibility to produce rooted cuttings all year round make cuttings propagation a good alternative for the production of plants, giving also the possibility to obtain genetically superior clones. On this basis, we assessed the influence of stock plants sex and type of cuttings (apical and intermediate) on the percentage of survival, rooting and vigor of the cuttings, together with the efficiency of this technique in the production of rooted cuttings of this species. So, cuttings from orthotropic shoots, collected in a clonal garden composed by feminine and masculine plants, had their survival percentages assessed at 60, 90, 120 and 150 days after installation of the experiment (DAI). Rooting in full sunlight area after 180 days, together with vigor characteristics of roots and aerial portion at 120 and 180 DAI were also evaluated. At 180 DAI, apical female cuttings presented the greatest rooting percentage (53.7%), number of roots (1.2) and average length of roots at the bottom of the rooting tray (4.4 cm). On the other hand, the applied cuttings procedures showed to be adequate to increase the rooting percentages of the species, which, supported by the fact that this technique is important for the formation of rooted cuttings to be used in the mini-cuttings technique, indicates that it can be considered efficient. RESUMO Araucaria angustifolia (araucária) é nativa do Brasil e sempre despertou interesse econômico por suas qualidades madeireiras e como fornecedora de pinhões para alimentação humana. A baixa viabilidade na germinação de suas sementes quando armazenadas e a possibilidade de produzir mudas durante o ano inteiro fazem com que a estaquia se apresente como alternativa para produção de mudas, gerando ainda a possibilidade de obtenção de clones geneticamente superiores. Com base nisso, avaliou-se a influência do sexo das matrizes e o tipo de estaca (apical e intermediária) na sobrevivência, enraizamento e vigor de suas estacas, bem como a eficiência desta técnica na produção de mudas da espécie. Para tanto, estacas de brotos ortotrópicos coletadas em jardim clonal de plantas masculinas e femininas foram avaliadas quanto à sobrevivência aos 60, 90, 120 e 150 dias após a estaquia (DAI) e o enraizamento a pleno sol a