High-efficiency plant production via direct somatic single embryogenesis from preplasmolysed cotyledons of Panax ginseng and possible dormancy of somatic embryos
High-efficiency plant production via direct somatic single embryogenesis from preplasmolysed cotyledons of Panax ginseng and possible dormancy of somatic embryos
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DOI：
10.1007/s002990050610
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发表时间：
1999-02-01
影响因子：
6.2
通讯作者：
Choi, KT
中科院分区：
文献类型：
--
作者：
Choi, YE;Yang, DC;Choi, KT
在缺乏生长调节剂的 Murashige 和 Skoog 培养基上培养的未成熟人参合子胚的子叶外植体直接形成体细胞胚，大多数处于多重状态，融合在一起并与亲本子叶外植体融合。当人参子叶外植体用1.0M蔗糖预处理24-72小时时，所有体细胞胚从子叶的所有表面单独发育，并且每个外植体的体细胞胚数量增加四倍。组织学观察发现，预质壁分离子叶中的单个体细胞胚均起源于表皮单细胞，而未经预处理的子叶中的多胚均起源于表皮和表皮下细胞团。当体细胞胚胎成熟到子叶阶段时，进一步生长停止并保持白色，可能表明处于休眠状态。赤霉酸 (GA(3))（超过 1.0 毫克/升）或冷冻处理（-2 摄氏度超过 8 周）是体细胞胚胎萌发的先决条件。超微结构观察发现，未经冷冻或GA(3)处理的体细胞胚子叶细胞含有大量脂质储备、致密的细胞质、前质体和未活化的线粒体，而冷冻或GA(3)处理后体细胞胚的子叶细胞高度空泡化，含有发育良好的叶绿体和活性状态的线粒体。 线粒体包围着许多嵴，表明体外发育的人参体细胞胚胎在成熟后可能以类似于合子胚胎的方式处于休眠状态。
Cotyledon explants of immature ginseng zygotic embryos cultured on Murashige and Skoog medium lacking growth regulators formed somatic embryos directly, most in a multiple state, fused together and to the parent cotyledon explants. When the cotyledon explants of ginseng were pretreated with 1.0 M sucrose for 24-72 h, all the somatic embryos developed individually from all surfaces of the cotyledons and the number of somatic embryos per explant was enhanced fourfold. Histological observation revealed that all the single somatic embryos from preplasmolysed cotyledons originated from epidermal single cells, whereas all the multiple embryos from cotyledons without pretreatment originated from epidermal and subepidermal cell masses. When the somatic embryos matured to the cotyledonary stage, further growth ceased and they remained white, probably indicating dormancy. Gibberellic acid (GA(3)) (over 1.0 mg/l) or chilling treatment (-2 degrees C for over 8 weeks) were prerequisites for the germination of somatic embryos. Ultrastructural observation revealed that the cotyledon cells of somatic embryos without chilling or GA(3) treatment contained numerous lipid reserves, dense cytoplasm, proplastids and non-activated mitochondria, whereas the cotyledon cells of somatic embryos after chilling or GA(3) treatment were highly vacuolated and contained well-developed chloroplasts and active-state mitochondria enclosing numerous cristae, indicating that in-vitro-developed somatic embryos of P. ginseng may be dormant after maturing in a manner similar to zygotic embryos.