玫瑰黄链霉菌Men-myco-93-63与其突变株间的DNA多态性分析和序列特征性扩增区域(SCAR)标记

玫瑰黄链霉菌(Streptomyces roseoflavus )Men-myco-93-63是分离自马铃薯疮痂病自然衰退土壤中的一株拮抗菌。前期研究表明，该菌株及其发酵液对棉花黄萎病菌（Verticillium dahliae）等多种重要的植物病原真菌具有较强的抑制作用。利用AFLP对Men-myco-93-63及其8株抗生素生物合成阻断突变株进行了基因组DNA多态性分析。结果表明，38对AFLP引物共产生3 142条谱带，其中2 362条为多态性谱带，占总带数的75.2 %。从96对引物中筛选得到了3对引物：E-CA/M-GA，E-GA/M-AC和E-GA/M-AG，分别扩增出254、312和209 bp 3条仅在Men-myco-93-63中存在，命名为EM254、EM312和EM209。将这3个片段回收、克隆和测序，成功地将其转化为SCAR标记，可以更加方便地用于对突变株的分子检测。

DNA Polymorphism Analysis and a Sequence-characterized Amplified Region (SCAR) Markers of Streptomyces roseoflavus Menmyco-93-63 and Its Mutant Strains

Streptomyces roseoflavus Men-myco-93-63 isolated from potato scab decline soil is an antagonistic strain. The strain and its fermentation can inhibit many pathogenic fungi and control the related important plant disease such as Verticillium wilt of cotton, cumber powdery mildew, and so on. The genetic polymorphism of Men-myco-93-63 with its eight antibiotic blocked mutants was analyzed using amplified fragment length polymorphism(AFLP) and 3 142 AFLP bands were amplified using 38 primer pairs, and 2 362(75.2 %) bands of them were polymorphic. Three of the 96 pairs of primers E-CA/M-GA, E-GA/M-AC and E-GA/M-AG were selected for AFLP. The bands with 254, 312 and 209 bp, which amplified by the three pairs of primers respectively, were present only in Men-myco-93-63 and named as EM254, EM312 and EM209. After recovery, cloning and sequencing，the three specific AFLP fragments were successfully converted into single locus PCR marker of a sequence-characterized amplified region (SCAR) which could be more easily to be used to detect mutants of Men-myco-93-63 at the molecular level.