目的:为了获得紫丁香蘑的最佳ISSR—PCR反应体系。方法:采用正交实验方法L16(4-5),对PCR反应的5个重要因素,TaqDNA聚合酶、Mg2+、模板DNA、dNTP以及引物的浓度在4个水平进行优化。结果:得到最佳的反应体系(25μL),包括1.5UTaqDNA聚合酶、2.5mmol/LMg2+、0.2mmol/LdNTP、0.15μmol/L引物、160ng模板DNA,最佳反应循环数为37。通过极差分析,对紫丁香蘑ISSR—PCR反应的影响程度从大到小依次为:TaqDNA聚合酶、dNTP、模板DNA、Mg2+、引物。使用该优化体系从23个ISSR引物中筛选出6个引物使不同地区的紫丁香蘑具有多态性。结论:研究结果为进一步采用ISSR分子标记方法研究紫丁香蘑的遗传多样性提供了研究基础。
Objective: In order to obtain the optimal ISSR - PCR amplification system of Lepista nuda, an orthogonal design experiment was proceeded in this paper. Method: The 5 factors (Taq DNA enzyme, Mg2 + , template DNA, dNTP, primers) with 4 levels Ll6 (45 ) was con- ducted. Result:The optimal reaction system:25 μL system,Taq DNA enzyme 1.5 U, Mg2+ 2. 5 mmol/L, template DNA 160 ng, dNTP 0. 2 mmol/L,primer 0. 15 μmol/L. The optimal response procedures need 37 cycles for PCR. The results of range analysis showed that the or- der of the five factors influence degree to ISSR, i. e. Taq DNA polymerase, dNTP, template DNA, Mg2 + , primers. Based on the optimized system,we selected 6 primers,which possessed polymorphism for the different sources Lepista nuda, among 23 ISSR primers. Conclusion: The results of this paper provided the research foundation for the further study of genetic diversity of Lepista nuda.