目的 建立甜叶菊甲基磺酸乙酯(EMS)离体诱变体系,通过SRAP检测鉴定获得甜叶菊耐盐突变体.方法 将"皖甜1号"-B1甜叶菊组培苗茎段接种在含有不同质量浓度NaCl的MS培养基中,进行耐盐临界NaCl质量浓度的筛选;用不同浓度的EMS处理甜叶菊组培苗茎段不同时间,筛选EMS诱变甜叶菊的适宜浓度和时间;将经过EMS诱变过的甜叶菊组培苗茎段接种在含有临界NaCl质量浓度的MS培养基上进行耐盐变异体的筛选,对存活的变异株通过SRAP标记进行耐盐性鉴定.结果 甜叶菊组培苗耐盐临界NaCl质量浓度为1.0%;EMS 诱变甜叶菊组培苗茎段的适宜浓度和时间范围为0.8%～1.0% EMS处理8～10 h;筛选出41株甜叶菊耐盐变异株,SRAP分子标记表明,4株在DNA水平上发生了变异,突变比率为9.76%.结论 初步建立了甜叶菊EMS离体诱变体系,为甜叶菊高产耐盐新品种的选育提供了一种新的育种途径.

Objective The in vitro mutation system of Stevia rebaudiana induced by ethylmethane sulfonate (EMS) was established , and the salt-tolerant mutants were identified by SRAP. Methods S. rebaudiana plantlets were inoculated on MS media containing NaCl with different concentration to screen the salt-tolerant critical concentration. Plantlets were treated with EMS at different concentration and for different time periods, and EMS mutagenized stems were inoculated on MS medium containing critical NaCl concentration to screen the tolerant variants by SRAP markers. Results The critical salt concentration of S. rebaudiana plantlets was 1.0%, and the suitable concentration and time of EMS were 0.8%—1.0% and 8—10 h. Among the screened 41 S. rebaudiana tolerant mutants by SRAP molecular markers, four were mutated at DNA level, and the mutation rate was 9.76%. Conclusion The in vitro mutagenesis system of S. rebaudiana with EMS has been established, which provides a new breeding way for high-yield salt-tolerant S. rebaudiana.

安徽科技学院自然科学基金项目(ZRC2013379);安徽省甜叶菊工程技术研究中心建设项目