ªDepartamento de Ciências Florestais, Universidade Federal de Lavras, universitário, s.n., CP 3037, CEP 37200-900, Lavras, MG, Brasil.
Departamento de Biologia, Universidade Federal de Lavras, universitário, s.n., CP 3037, CEP 37200-900, Lavras, MG, Brasil.
Braz J Biol. 2021 Jul-Sep;81(3):566-574. doi: 10.1590/1519-6984.225119.
The native stands of 'candeia' (Eremanthus erythropappus) have been explored through management plans due to the economic potential of essential oil. The rescue of adult trees, as well as the application of silvicultural techniques that favor the restoration of the stand, can contribute to the genetic conservation of this species. This study's objective was to assess the efficiency of propagation techniques for the rescue of 26 matrices of 'candeia' in a natural managed stand and discussion about the rhizogenesis. In August 2017, trees were induced to regrowth by coppice, followed by exposure and scarification of roots. The emergence of shoots and morphology were evaluated according to the origin (i.e., stump or root). After that period, 19 matrices had their sprouts collected for the preparation of apical cuttings. Indole-3-butyric acid (IBA) was applied at the base of the cuttings. Cutting survival at greenhouse exit (GE), rooting at shade house exit (SHE), morphology and root anatomy were evaluated. In 189 days, the scarification of roots promoted 76.92% of budding. The percentage of sprouted matrices, number of shoots per matrice, length, diameter, and shoot length/diameter ratio increased over time. Only 12.2% of the cuttings survived in GE, and of these, 7.9% rooted in SHE. The cutting resulted in the formation of a clonal mini-garden of 'candeia', with seven of the 19 matrices submitted to propagation. The anatomical analyses showed that bud formation occurs from cell redifferentiation in the phloem parenchyma, and presence of crystals on the walls of the vessel elements of the secondary xylem. The shoots induction from scarification of roots could be used as a silvicultural practice for the reestablishment of the native fragments handle.
“坎迪亚”（Eremanthus erythropappus）的原生林已经通过管理计划进行了探索，因为其精油具有经济潜力。抢救成年树木，并应用有利于林分恢复的造林技术，可以为该物种的遗传保护做出贡献。本研究的目的是评估在天然管理林分中抢救 26 株“坎迪亚”母株的繁殖技术的效率，并讨论其生根情况。2017 年 8 月，通过萌蘖对树木进行了再生长诱导，然后对根系进行了暴露和刻伤。根据起源（即树桩或根）评估芽的出现和形态。在那个时期之后，有 19 个母体的新芽被收集起来准备制作顶芽插条。在插条基部涂抹吲哚丁酸（IBA）。温室出口（GE）的插条成活率、遮荫出口（SHE）的生根率、形态和根解剖结构进行了评估。在 189 天内，根部刻伤促进了 76.92%的萌芽。发芽母体的百分比、每个母体的芽数、长度、直径和芽长/直径比随着时间的推移而增加。只有 12.2%的插条在 GE 中存活，其中 7.9%在 SHE 中生根。插条形成了“坎迪亚”的克隆迷你花园，19 个母体中有 7 个进行了繁殖。解剖分析表明，芽的形成是从韧皮部薄壁细胞的细胞再分化开始的，并且在次生木质部导管分子的壁上存在晶体。根刻伤诱导芽的形成可以作为重建原生林分的一种造林实践。
