摘要
以 Na N3诱变处理的沙打旺胚性愈伤组织为材料 ,用甲硫氨酸类似物—乙硫氨酸为选择剂 ,筛选到 1株抗性稳定且能再生植株的抗 0 .6mmol L-1乙硫氨酸变异系。该变异系细胞对乙硫氨酸的抗性是野生型细胞的 8倍。当把变异系愈伤组织传入体细胞胚胎诱导培养基上 ,平均体细胞胚胎发生频率为13.9% ,平均每 g鲜重愈伤组织可产生 2 1个体细胞胚 ,分别为野生型细胞的 2 2 .9%和 11.1%。氨基酸分析表明 ,变异系愈伤组织及其再生植株游离甲硫氨酸含量分别是野生型的 2 .5倍和 4倍。在含选择剂的愈伤组织诱导培养基中 ,变异系再生植株茎切段愈伤组织诱导率达 72 .1% ,而野生型再生植株茎切段无愈伤组织形成 。
One stable variant of Astragalus adsurgens resistant to 0.6 mmol L -1 ethionine was isolated from embryogenic calli mutagenized with 0.1 mol L - 1 NaN 3 for 3 hours. The resistance of variant to ethionine was 7 times higher than that of the wild type. The variant calli were capable of regenerating plan tlets through somatic embryogenesis in the differentiation medium without ethion ine, and the mean frequency of calli producing somatic embryos and the number of somatic embryos per gram fresh weight callus were 13.9% and 21.4, only 22.9% an d 11.1% of the wild type, respectively. The variant callus and its regenerants an alyzed for free amino acid content were found to contain 2.5 times and 4 times a s much methionine as the wild type, respectively suggesting that its resistance to ethionine was due to the increase in free methionine level. Stem segments from the variant regenerants showed similar callus formation on both normal and 0.6 mmol/L ethionine containing medium while stem segments of the wild type re generants only formed callus on ethionine free medium. This result indicated cl early that ethionine resistance was expressed during callus induction and growth of the variant.
出处
《作物学报》
CAS
CSCD
北大核心
2000年第6期789-794,共6页
Acta Agronomica Sinica
基金
国家自然科学基金和博士后科学基金资助
关键词
牧草
沙打旺
抗乙硫氨酸变异系
筛选
甲硫氨酸
Astragalus adsurgens Pall.
Ethionine re sistant variant
Somatic embryogenesis
Plant regeneration
