VEGETATIVE RESCUE AND ROOTING OF CUTTINGS OF DIFFERENT STOCK PLANTS OF Sequoia sempervirens

Abstract

Sequoia is a fast-growing, long-living species, producing durable timber. The aim of this study was to test different methods for the vegetative rescue of Sequoia sempervirens trees over 40 years old, made at different periods of the year, and, later, testing the rooting of individualized cuttings in planned arrays. Twenty-four individual sequoias were rescued, applying girdling and semi-girdling at three different heights (-10, 0, and 30 cm). The first collection was made 90 days after application of the treatments, being repeated at 150, 240, and 360 days. The percentage of budding trees and the number of shoots per array were registered. In all collections, shoots produced cuttings, which were placed for rooting in mini-tunnels. Cutting survival (%), rooting (%), and number of roots were registered, per array, and per collection. The species vegetative rescue proved to be efficient for the production of shoots for stem cuttings, especially with girdling at 30 cm and semi-girdling at -10 cm. However, it is difficult to define the best method, mainly because of the genetic effect among stock plants. The rooting of cuttings, of recovered material, presented good results (average >65%), also with great differences among stock plants. The potential for rooting of cuttings varied according to different planting periods, with high rooting rates in all seasons, especially in summer. Sequoia sempervirens shows the potential for vegetative rescue and cloning by rooting of cuttings, and this may lead to new studies, with a view towards fixing clones. RESGATE VEGETATIVO E ENRAIZAMENTO DE ESTACAS DE DIFERENTES MATRIZES DE Sequoia sempervirensRESUMO: Sequoia é uma espécie de rápido crescimento, longeva e de madeira durável. O objetivo do estudo foi testar diferentes métodos de resgate vegetativo em árvores com mais de 40 anos de idade de Sequoia sempervirens, realizados em distintas épocas do ano e posterior enraizamento de estacas individualizadas por planta matriz. Resgataram-se 24 indivíduos de sequoia, aplicando-se anelamento e semianelamento em três diferentes alturas (-10, 0 e 30 cm). A primeira coleta foi efetuada 90 dias após aplicação dos tratamentos, sendo repetida aos 150, 240 e 360 dias. Contabilizou-se a porcentagem de árvores com brotações e o número de brotações por matriz. Em todas as coletas as brotações originaram estacas que foram colocadas para enraizar em estufim. No enraizamento das estacas analisou-se a sobrevivência (%), enraizamento (%) e número de raízes por matriz por coleta. O resgate vegetativo da espécie mostrou-se eficiente na produção de brotações para a estaquia, destacando-se o anelamento a 30 cm e o semianelamento a -10 cm. Entretanto, há dificuldade em definir qual o melhor método, principalmente em função do efeito genético entre matrizes. O enraizamento de estacas do material resgatado apresentou bons resultados (média >65%), também com grande diferença entre as matrizes. Diferentes épocas de estaquia alteraram o potencial de enraizamento, contudo, com altos índices de enraiz...

Roots of Mini-Cutting of Clones of Sequoia Sempervirens in Different Seasons of the Year

“…The variation in rooting capacity is similar to that found by Pereira et al (2017) in Sequoia sempervirens and other woody species such as Chamaecyparis nootkatensis (Krakowski et al, 2005), Taxus globosa (Muñoz-Gutiérrez et al, 2009) and many others. The clonal variation in rooting capacity is an attribute in many studies on genetic effects (Owais, 2010) and "C" clonal effect; the latter defined as unique physiological or morphological characteristics for the branch (stake) reflecting in its growth environment.…”

Vegetative rescue of Cedrela fissilis Vell. by the rooting of cuttings from epicormic and canopy sprouts

“…This indicates that the species does not have natural sprouting capacity, without a sprouting activation mechanism, such as girdling. Some species naturally sprout, as reported by PEREIRA et al (2017b) in Sequoia sempervirens. All trees that went through the girdling rescue technique (20 cm and 40 cm) presented more than 67% epicormic sprouts (Table 1).…”

“…The rescue method and soil fertility can also influence sprouting in Ilex paraguariensis . PEREIRA et al (2017b) demonstrates that the rescue technique and the genetics of Sequoia sempervirens trees can influence the rooting of cuttings. The rescue technique on older C. fissilis trees needed to be tested to assess the influence on the production of epicormic sprouts.…”

“…Macleish. (MELO et al, 2012) also in exotic species implanted in Brazil, such as Sequoia sempervirens D. Don (PEREIRA et al, 2017b), Tectona grandis L. f. (BADILLA et al, 2016), Eucalyptus cloeziana F. Muell. (ALMEIDA et al, 2007) and Toona ciliata var.…”

ROOTING ENVIRONMENTS IN Sequoia sempervirens MINI-CUTTINGS OF CLONE A228

“…Navroski et al (2015) achieved rooting of almost 80% using 4,000 mg L -1 of AIA (indole-3-acetic acid). Rooting results greater than 60% were also obtained for Sequoia sempervirens by Pereira et al (2017a) and Pereira et al (2017b). of Sequoia sempervirens mini-cuttings in different rooting environments, evaluated monthly from 30 to 150 days.…”