Radice Silvia
Centro de Estudios Farmacológicos y Botánicos (UBA-CONICET), Ciudad Autónoma de Buenos Aires, Argentina.
Methods Mol Biol. 2010;589:187-95. doi: 10.1007/978-1-60327-114-1_18.
Codiaeum variegatum (L) Blume cv. "Corazon de oro" and cv. "Norma" are successfully micropropagated when culture are initiated with explants taken from newly sprouted shoots. The establishment and multiplication steps are possible when 1 mg/L BA or 1 mg/L IAA and 3 mg/L 2iP are added to MS medium, according to the cultivar respectively selected.Adventive organogenesis and somatic embryogenesis are induced from leaf explants taken from in vitro buds of croton. On leaf-sectioned of "Corazon de oro" cultured in vitro, 1 mg/L BA stimulates continuous somatic embryos development and induces some shoots too. Replacing BA with 1 mg/L TDZ induces up to 100% bud regeneration in the same explants. On the other hand, leaf-sectioned of C. variegatum cv. Norma does not start somatic embryo differentiation if 1 mg/L TDZ is not added to the MS basal medium. Incipient callus is observed after 30 days of culture, and then, subculture to MS with 1 mg/L BA allows the same process to show on the "Corazon de oro" cultivar. Somatic embryos show growth arrest that is partially overcome by transfer to hormone-free basal medium with activated charcoal. Root induction is possible on basal medium plus 1 mg/L IBA. Plantlets in the greenhouse have variegated leaves true-to-type.
用取自新萌发嫩枝的外植体起始培养时，变叶木（Codiaeum variegatum (L) Blume）品种“金心”和“诺玛”成功实现了微繁殖。根据分别选择的品种，向MS培养基中添加1 mg/L的苄氨基腺嘌呤（BA）或1 mg/L的吲哚乙酸（IAA）以及3 mg/L的异戊烯腺嘌呤（2iP）时，建立培养物和增殖步骤是可行的。从巴豆离体芽上取下的叶片外植体可诱导不定器官发生和体细胞胚胎发生。在体外培养的“金心”叶片切片上，1 mg/L的BA刺激体细胞胚胎持续发育并也诱导出一些芽。用1 mg/L的噻苯隆（TDZ）替代BA可在相同外植体中诱导高达100%的芽再生。另一方面，如果不向MS基本培养基中添加1 mg/L的TDZ，变叶木品种“诺玛”的叶片切片不会开始体细胞胚胎分化。培养30天后观察到初期愈伤组织，然后，转接到添加1 mg/L BA的MS培养基上，相同过程在“金心”品种上表现出来。体细胞胚胎出现生长停滞，通过转移到添加活性炭的无激素基本培养基可部分克服这一问题。在基本培养基加1 mg/L的吲哚丁酸（IBA）上可诱导生根。温室中的小植株具有与原品种一致的杂色叶片。
