小苍兰种质遗传多样性的ISSR分析

利用ISSR(Inter Simple Sequence Repeat)分子标记对12份小苍兰(Freesia refracta)种质进行了遗传多样性分析研究。从34条ISSR引物中筛选出了12条适宜的引物。这12条引物中每条引物可扩增出5~11条DNA片段，共扩增了96个条带，其中多态性片段62条，平均每条引物可产生5.2条多态性片段，多态性条带比率(PPB)为64.6%。经NTSYS-pc分析，12份小苍兰种质间的遗传距离(GD)的变化范围为0.123~0.907，平均为0.442。根据Nei’s相似系数建立了UPGMA聚类图，在相似系数为0.56时，可将紫色花系的小苍兰种质与其它种质分开，形成两个组。结果表明，ISSR分子标记可有效地分析小苍兰种质资源的遗传多样性和亲缘关系，为小苍兰的杂交育种和新品种保护提供理论基础。

ISSR Analysis of Genetic Diversity in Freesia refracta Germplasm

Genetic diversity of 12 Freesia refracta accessions was detected and assessed using inter simple sequence repeat (ISSR) markers. From 34 ISSR primers, 12 primers were selected to perform ISSR-PCR. 5~11 DNA fragments were amplified with each of the 12 primers. Total 96 DNA bands were obtained, of which 62 bands had polymorphism, and average 5.2 polymorphic bands per primer. The percentage of polymorphic bands (PPB) was 64.6%. Computed with NTSYS-pc, the genetic distance (GD) of the 12 F. refracta accessions ranged from 0.123 to 0.907, and average 0.442. According to the UPGMA dendrogram based on Nei’s genetic similarity, the 12 materials were divided into 2 groups at 0.56. The accessions with purple flowers belong to the group 1, and the others to the group 2. The results demonstrated that ISSR is a useful tool to analyze the genetic diversity and genetic relationship among F. refracta accessions, which provides a scientific basis for cross breeding and new varieties protection of F. refracta.