甜菜SSR反应体系优化及重要农艺性状分子标记

Study on Optimization for SSR Reaction System and Molecular Marker of Important Agronomy Traits in Beta vulgaris

【目的】为选育优质甜菜新品种,利用SSR法筛选与高糖、高产、耐盐相关的分子标注。【方法】研究对甜菜SSR-PCR反应体系进行优化,并利用SSR分子标记方法和分离群体分组分析法(Bulked Segregate Analysis,BSA)对具有高糖/低糖、低产/高产、耐盐/不耐盐三种重要农艺性状的甜菜亲本和F2代植株进行分析。【结果】研究建立了适宜甜菜的SSR-PCR反应体系为:20μL反应体系中含1×Buffer、2.0 mmol/L Mg2+、1.5 U Taq DNA聚合酶、0.20 mmol/L dNTP、1.5μmol/L引物、60 ng DNA模板。依据优化体系,对不同农艺性状的甜菜亲本与F2代进行SSR-PCR扩增分析,高糖性状获得了200和100 bp两条与高糖性状连锁的标记,250和230 bp两条与高产性状连锁的标记,550、250和100 bp三条与耐盐性状紧密连锁的分子标记。【结论】研究获得的7条特异条带是与甜菜重要农艺性状连锁的分子标记,将为甜菜的育种工作提供重要的理论基础。

[Objective] In order to breed new varieties of sugar beet,provided the scientific basis for molecular marker assisted selection breeding.[Method] In this study,we optimized the beet SSR reaction system,employed SSR markers and the method of BSA （Bulked Segregate Analysis） to analyze high/low sugar,low/high yield,salt tolerance/intolerance of three important agronomic traits of beet parents and F2 progeny plants.[Result] The SSR reaction system was optimized,and the best reaction system is that 20 μl reaction system contained 1 × PCR buffer,2.0 mmol/L Mg2 ＋,1.5 U Taq DNA polymerase,0.20 mmol/L dNTP,1.5 μmol/L primer and 60 ng DNA template.On the basis of this optimal reaction system,two linked markers （200 and 100 bp） were obtained from high glucose beets; two linked markers（250 and 230 bp）were identified from high product beets; and three linked markers（550,250 and 100 bp）were linked with salt-tolerance trait.[Conclusion] Seven bands linked with the important agronomy traits of molecular markers had been obtained,which would offer important rationale for molecular marker breeding of sugar beets.