基于ISSR标记的大菊品种资源遗传多样性分析

【目的】大菊品种数量众多，形态繁杂。本研究通过探讨不同瓣类大菊品种的遗传多样性，为菊花品种分类和品种演化研究提供重要资料。【方法】选取涵盖大菊品种5个瓣类的150个品种，采用ISSR分子标记进行遗传多样性分析。【结果】从50对引物中筛选出的10对引物共检测到清晰可重复的229个位点，其中多态性位点220个，多态性位点百分率（PPB）96.07%，Nei’s基因多样性指数（He）和Shannon信息指数（I）分别为0.3485和0.5154；5个瓣类内的遗传多样性水平都比较高，其中平瓣类最高（PPB＝95.20%），桂瓣类（PPB＝86.90%）和匙瓣类（PPB＝89.52%）最低；瓣类类群间遗传分化程度较低，遗传多样性主要来源于不同花型内品种间的变异。在瓣类的UPGMA聚类中，聚类结果与瓣类形态差异显著相关。【结论】ISSR可以有效揭示大菊品种瓣类间的遗传多样性、分化程度和亲缘关系，研究结果对于品种演化和分类鉴定研究具有重要参考价值。

Genetic Diversity of Large-Flowered Chrysanthemum Cultivars Revealed by ISSR Analysis

【Objective】 Large-flowered chrysanthemum processes numerous cultivars with complex morphological types. This study aims to facilitate the research on classification and evolution history of chrysanthemum cultivars by a probe in genetic diversity of chrysanthemum cultivars belonging to different floral types respectively.【Method】 The genetic diversity of 150 large-flowered chrysanthemum cultivars belonging to 5 floral types were investigated using 10 primers with clear bands and steady repetitiveness chosen from 50 ISSR primers. 【Result】 A total of 229 bands were amplified, of which 220 were polymorphic loci. The main index were: PPB＝96.07%, He＝0.3485, I＝0.5154(at species level). The genetic variation in each floral types is quite high, in which the Flat-petal group is the highest (PPB＝95.20%), whereas the Anemone-petal group (PPB＝86.90%) and the Spoon-petal group (PPB＝89.52%) were the lowest. The level of genetic differentiation among floral types was very low, and genetic diversity mainly derived from variations of cultivars at flower type level. The result of UPGMA cluster was highly relevant to morphological variations among floral types. 【Conclusion】 The result of the research shows that genetic diversity of large-flowered chrysanthemum cultivars can be revealed well and truly by ISSR molecular marker，which processes of great meaning to research of classification, identification and evolution of chrysanthemum cultivars.