Key Message

A protocol for somatic embryogenesis here described, open the possibility for the clonal propagation of selected trees of the natural hybrid of mahogany Swietenia macrophylla King ×  S. mahagoni (L.) Jacq.

Abstract

Young leaves were collected from greenhouse plants cloned from epicormic shoots of a 35-year-old interspecific hybrid of mahogany (Swietenia macrophylla King × S. mahagoni (L.) Jacq.) tree. All explants formed calli when cultured on a medium containing Murashige and Skoog salts, 3% sucrose (Lobachemie), 0.3% Phytagel (Sigma) and 4.52 µM 2,4-dichlorophenoxyacetic acid and regardless of the concentration of kinetin used (4.65, 9.29 or 13.94 µM). After 3 months, the calli were separated from the leaf segments and subcultured on differentiation medium. The greatest number of calli (38–40%) forming somatic embryos, after 6 months of culture, was obtained on the differentiation media containing 4.44 or 6.66 µM benzyladenine (BA). Secondary or repetitive somatic embryogenesis was achieved when primary cotyledonary somatic embryos were subcultured on fresh medium of the same composition as differentiation medium containing 4.44 µM BA. Numerous cotyledonary somatic embryos were developed after 5 weeks of subculture on differentiation medium with decreased BA concentration (1.77 µM). Thereby, developed somatic embryos had different morphological features, which are described herein. The highest frequency of somatic embryo germination (62%) was obtained using half-strength MS medium supplemented with 0.27 µM of BA plus 0.145 µM of gibberellic acid. Twenty-five percent of the plantlets developed normally in the greenhouse. In this study, a somatic embryogenesis system was established from leaf explants of a natural hybrid of mahogany Swietenia macrophylla King × S. mahagoni (L.) Jacq was established, hence opening the possibility for the clonal propagation of selected trees of this natural hybrid.

中文翻译：

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桃花心木种间杂种 (Swietenia macrophylla King × S. mahagoni (L.) Jacq.) 叶的体细胞胚胎发生和植物再生

关键信息

此处描述的体细胞胚胎发生协议为 红木 Swietenia macrophylla King ×  S. mahagoni (L.) Jacq天然杂交种的选定树木的克隆繁殖提供了可能性。

摘要

从 35 年历史的桃花心木种间杂种（Swietenia macrophylla King ×  S. mahagoni(L.) Jacq.) 树。当在含有 Murashige 和 Skoog 盐、3% 蔗糖 (Lobachemie)、0.3% Phytagel (Sigma) 和 4.52 µM 2,4-二氯苯氧乙酸的培养基上培养时，所有外植体都形成愈伤组织，无论使用的激动素浓度如何（4.65、9.29 或13.94 µM）。3个月后，将愈伤组织与叶段分离并在分化培养基上继代培养。在培养 6 个月后，在含有 4.44 或 6.66 µM 苄基腺嘌呤 (BA) 的分化培养基上获得了最多数量的愈伤组织 (38–40%)。当初级子叶体细胞胚胎在与含有 4.44 µM BA 的分化培养基相同成分的新鲜培养基上进行传代培养时，实现了二次或重复的体细胞胚胎发生。在 BA 浓度降低 (1.77 µM) 的分化培养基上继代培养 5 周后，开发了许多子叶体细胞胚胎。因此，发育的体细胞胚胎具有不同的形态特征，如本文所述。体细胞胚胎萌发的最高频率 (62%) 是使用补充有 0.27 µM BA 和 0.145 µM 赤霉酸的半强度 MS 培养基获得的。25% 的幼苗在温室中正常发育。在这项研究中，从桃花心木天然杂交种的叶外植体中建立了体细胞胚胎发生系统。体细胞胚胎萌发的最高频率 (62%) 是使用补充有 0.27 µM BA 和 0.145 µM 赤霉酸的半强度 MS 培养基获得的。25% 的小苗在温室中正常发育。在这项研究中，从桃花心木天然杂交种的叶外植体中建立了体细胞胚胎发生系统。体细胞胚胎萌发的最高频率 (62%) 是使用补充有 0.27 µM BA 和 0.145 µM 赤霉酸的半强度 MS 培养基获得的。25% 的幼苗在温室中正常发育。在这项研究中，从桃花心木天然杂交种的叶外植体中建立了体细胞胚胎发生系统。Swietenia macrophylla King ×  S. mahagoni (L.) Jacq 的建立，为选择这种天然杂交种的树木进行无性繁殖提供了可能性。