摘 要 ：以中苜一号紫花苜蓿(Medicago sativa L.cv.Zhang mu No.1)为材料,对SCAR反应中的引物浓度、退火温度、Mg2+、dNTP浓度、模板DNA用量及Taq酶用量进行优化。结果表明:在3对SCAR中有2对引物出现目标扩增带,其中以SCAR1的效果最好;适宜反应体系总体积为25μL、Mg2+浓度2.5mM、dNTP浓度200μM、引物浓度0.5μM、Taq酶1.5U、模板DNA为50~100ng;优化后的反应体系能得到清晰稳定的SCAR扩增条带,可用于苜蓿耐盐性分子标记鉴定分析。
Abstract:Alfalfa cultivar “Zhongmu No.1” was used as materials for extracting DNA in present experiment. The gradient tests on the concentration of Mg2+, dNTP, SCAR primer, template DNA, TaqDNA polymerase were conducted. Results show that two of three primer sets could amplify target bands, among which SCAR1 was the suitable primer pair. The stable reaction system of SCAR with a total volume of 25 μl, consisting of Mg2+ of 2.5 mM concentration, dNTP at 200 μM, SCAR primer at 0.5 μM, TaqDNA polymerase at 1.5 U, and 50～100 ng template DNA. A clear, stable band can be amplified with the optimized reaction system which can be used in molecular marker diagnoses of salt tolerance of the alfalfa populations.