Araucaria Clonal Forestry: Types of Cuttings and Mother Tree Sex in Field Survival and Growth

Abstract

Araucaria angustifolia (Bert.) O Kuntze (Paraná pine or Araucaria) is a potential forestry native species for Brazilian silviculture. However, a number of challenges and technical restraints persist, hindering its silvicultural expansion, among which are the lack of cloning technologies of superior genetic materials and their assessment under field conditions. Thus, we evaluated the potential use of araucaria plants derived from cuttings and seeds for timber production, by assessing field survival, growth and strobilus production using cuttings from male and female plants, collected from different positions, compared with those produced by sexual reproduction. Clones of male and female trees from different types of cuttings and seedlings were planted in 3 x 3 m spacing. The experiment was conducted in a completely randomized design of one tree plot with three treatments. Female clones and apical cuttings showed higher growth in diameter at breast height (6.4 cm) and total height (3.6 m) 74 months after planting, followed by seedlings and other clones, with similar results. We conclude that cuttings technique is potential for araucaria propagation for wood production purposes, and it is favored by the use of apical cuttings from female mother trees. SILVICULTURA CLONAL DE ARAUCÁRIA: TIPO DE ESTACA E SEXO DA PLANTA MATRIZ NA SOBREVIVÊNCIA E CRESCIMENTO EM CAMPO RESUMO:Araucaria angustifolia é uma espécie nativa potencial para a silvicultura brasileira. No entanto, uma série de desafios e limitações técnicas ainda persistem, dificultando sua expansão silvicultural, dentre os quais se destaca a falta de tecnologias de clonagem de materiais genéticos superiores, bem como sua avaliação em condições de campo. Assim, objetivou-se avaliar a potencialidade da utilização de mudas de araucária oriundas de estaquia e de sementes para produção madeireira, por meio da avaliação da sobrevivência e crescimento a campo. Clones provenientes de matrizes masculinas e femininas, de diferentes tipos de estacas e mudas de sementes foram plantadas em espaçamento 3 x 3 m. O experimento foi conduzido em delineamento inteiramente casualizado, com três tratamentos e parcelas de uma planta (one tree plot). Clones do sexo feminino e de estacas contendo o ápice apresentaram maior crescimento em diâmetro à altura do peito (6,4 cm) e altura total (3,6 m) aos 74 meses após o plantio, seguidas das de sementes e demais clones, com resultados similares. Conclui-se que a estaquia é uma técnica potencial de produção de mudas de araucária para fins madeireiros e é favorecida pela utilização de estacas proveniente de matrizes femininas e com ápice.

Vegetative propagation and application of clonal forestry in Brazilian native tree species

“…Other techniques for epicormic sprout induction in native tree species were evaluated, standing out pruning of canopy branches, sprouting of detached branches in a greenhouse, and stem span (Wendling et al, 2009aRickli et al, 2015). For A. angustifolia, pruning was carried out on the orthotropic tip (apex) of adult plants for grafting and early seed production (Wendling et al, 2016b), as well as on plagiotropic branches (lateral branches) for cuttings (Wendling et al, 2009a). The branches of this same species (Wendling et al, 2009a) and of I. paraguariensis and Campomanesia xanthocarpa O.Berg (Teleginski, 2016) were detached in a greenhouse, aiming vegetative propagation by cuttings.…”

Indirect selection of maize genotypes based on associations between root agronomic and anatomical characters

“…This is supported by Souza (2009), who comments that thin roots (up to 2 mm in diameter) are more responsible for the absorption of water and nutrients than thicker roots, whose function is more concerned about fixing the plant in the soil. Wendling et al (2016) report that plants that have a higher volume of thin roots in their early development stage exhibit greater adaptive capacity in terms of water and nutritional deficit.…”

Enraizamento de estacas de murici (Byrsonima gardneriana A. Juss) utilizando ácido Indolbutírico na produção de mudas

“…Porém são escassos estudos voltados para espécies nativa da caatinga com uso dessa técnica com finalidade de resgate e conservação de recursos genéticos florestais e revegetação de áreas degradadas (VALENTINE et al, 2011;LIMA et al, 2015;CRUZ SILVA et al, 2015;WENDLING et al, 2016).…”