锯叶棕体细胞胚胎发生及植株再生体系的建立

从锯叶棕成熟种子中成功实现体细胞胚胎发生和植株再生。成熟种子放在MS培养基上培养,加入0.15%活性炭,452μmol/L 2,4-D和14.7μmol/L N6-2i P,所有成熟合子胚培养5周后长出体胚簇,12周后,外植体转移到2,4-D浓度减到90.4μmol/L的MS培养基中进行体胚增殖,之后体胚转移到含有0.9,9μmol/L TDZ或没有生长调节剂的基本培养基中转化成小植株。9μmol/L TDZ对植株再生是无效的,然而,在0.9μmol/L TDZ中作次培养有12%胚胎能长成完整植株,没有生长调节剂中35%胚胎长出嫩枝,这些嫩枝转移到含有22.2μmol/L NAA的培养基中全部都会生根。picloram和2,4-D对锯叶棕幼苗愈伤的诱导效果最佳,6-BA次之,对子叶来说,picloram和2,4-D对愈伤的诱导起不到任何作用,而对茎尖的诱导效果最好。

Somatic Embryogenesis and Establishment of Plant Regenerative System of Saw Palmetto

Somatic embryogene sis and plant regeneration is achieved through saw palmetto (Serenoa repens). Embryos are cultured on Skoog medium with 0.15% (w/V) activated charcoal, 452 μmol/L 2,4-dichlorophenoxyacetic acid (2,4-D) and 14.7 μmol/L N6-(2-isopentenyl) adenine (2iP). After culture initiation for 5 weeks, clusters of somatic embryos is developed. After 12 weeks, explants are transferred to the same medium with the amount of 2,4-D reduced to 90.4 μmol/L which resulted in somatic embryo proliferation. Somatic embryos are then transferred to the basal medium containing 0.9, 9 μmol/L thidiazuron (TDZ) or no growth regulator for conversion into plantlets. The 9 μmol/L TDZ treatment is ineffective for plant regeneration. However, 12%of the embryos subcultured on 0.9 μmol/L TDZ are able to produce complete plantlets. Shoot production was obtained from 35%of the embryos subcultured in the absence of growth regulators. Shoot production is obtained from 35% of the embryos subcultured in the absence of growth regulators. Rooting (100%) is achieved after these shoots are transferred into medium containing 22.2μmol/Lα-naphthaleneacetic acid (NAA). Picloram and 2,4-D is better for callus induction of saw palm than 6-BA. Picloram and 2,4-D treatment are ineffective for callus induction of cotyledon, but best for stem tip.