小麦成熟胚离体培养及植株再生技术优化

摘要

The effects of different factors on the callus induction and plant regeneration from mature embryos of 27 winter wheat genotypes of Zhoumai were studied.The shoot differentiation rate of callus from mature embryos with cross cutting was 66.7％,2.1 and 4.3 times higher than that from fragmented embryos and whole embryos,respectively.Although Dicamba and 2,4-D induced callus from explants with high frequency (96.3 ％-97.7 ％),Dicamba was more effective for the induction of embryogenic callus,while the callus differentiation rate from 2,4-D was 4.0 times greater.When the concentration of Dicamba was 2.0-4.0 mg/L,the rate of callus induction and differentiation were both higher.Supplement of additional cytokinins to callus differentiation medium had different effects on the rate of callus differentiation.The best rate of shoot formation was observed with addition of 2.0 mg/L 6-BA (45.8％).When contact of explants with callus induction medium was two or three weeks the rate of shoot formation was high.Callus drying treatment of 6 h increased the differentiation rate slightly,but there was no significant difference compared with no desiccation.%本实验利用冬小麦品种周麦27成熟胚进行了愈伤组织诱导和植株再生技术的优化,以提高小麦成熟胚离体再生频率,为以成熟胚进行遗传转化奠定基础.探讨了外植体不同接种方法、Dicamba浓度和细胞分裂素种类、转分化时间和愈伤组织干燥处理等因素对小麦成熟胚愈伤组织诱导和分化的影响.结果表明,1)小麦成熟胚十字形切割法接种愈伤组织分化率较高,达到66.7％,分别是刮胚法和整胚接种的2.1和4.3倍;2)附加2,4-D和Dicam-ba均可以高频率诱导成熟胚愈伤组织的形成,但Dicamba诱导形成的愈伤组织分化率高于2,4-D的达4倍之多,在Dicamba浓度为2.0～4.0 mg/L时愈伤组织诱导和分化效果较好;3)愈伤组织在附加2.0 mg/L 6-BA的分化培养基上分化率最高为45.8％,其次为在不含激素或含KT 2.0 mg/L时分化率分别达到38.5％和37.0％,而在附加TDZ和ZT时分化率较低;4)成熟胚外植体在诱导培养2～3周后进行分化培养,绿苗分化率最高;5)愈伤组织分化前干燥处理6h愈伤组织分化率略有提高,但与未干燥处理的相比差异不显著,而干燥12 h后分化率却明显降低.