【作者】 李保印；

【导师】 张启翔；

【作者基本信息】 北京林业大学 ， 园林植物与观赏园艺， 2007， 博士

【摘要】 牡丹(Paeonia suffruticosa Andr.)是中国特产传统名花，具有2000多年的栽培历史，品种类型丰富。目前，栽培与生理等方面报道较多，遗传多样性方面，虽有报道，但不够系统、深入；品种资源保存方面，多是采取不加选择地全部实地保存，既浪费土地，又给深入研究和高效利用带来不便。核心种质的构建与应用研究是解决上述问题最有效的方法之一。本研究以中原牡丹品种为研究对象，采用表型与分子标记相结合的方法，对400个品种进行了遗传多样性分析和核心种质构建研究。主要结果如下：1．根据品种来源、分类体系等基本数据和形态、分子标记特征数据，建立了中原牡丹400个品种的表型数据库和120个品种的分子数据库。2．按整体和分组不同方式进行表型性状遗传多样性分析，发现：牡丹品种整体遗传多样性丰富，Shannon多样性指数达到了0.9966。不同组间及各性状的遗传多样性丰富度不一。根据分析结果提出了进一步丰富中原牡丹品种遗传多样性的建议。3．首次研究了中原牡丹品种资源核心种质构建的方案与策略，选择按花型分组，组内以平方根法确定取样量，并用类平均法(UPGMA)聚类抽样，构建了由120份(占总体种质的30％)材料组成的初级核心种质；表型水平上初级核心种质覆盖了原始总体种质的品种类型和性状，Shannon遗传多样性指数对总体种质的代表性达到了99.12％，各性状的Shannon遗传多样性指数与总体差异不显著。5．对初级核心种质120个品种进行了ISSR和AFLP标记，8条ISSR引物共扩增出244条带，多态性带93.3％，平均PIC值为0.44，8对AFLP引物共扩增出1162条带，多态性带占97.6％，平均PIC值0.67，从分子水平上进一步证明了初级核心种质具有丰富的遗传多样性。6．分别使用随机、表型数据、AFLP、ISSR、AFLP+ISSR、表型数据+AFLP、表型数据+ISSR、表型数据+AFLP+ISSR共8种压缩方式对初级核心种质进行抽样压缩，构建了8个各自含有60个品种的核心种质候选群体。表型和分子水平检验结果表明：采用“表型数据+AFLP+ISSR”压缩法构建的核心种质既能很好地代表初级核心种质，又能很好地代表总体种质，各检验指数及品种间平均遗传距离均高于原始总体种质，保留了总体种质的15％，对原始总体的表型保留比例在99％以上。更多还原

【Abstract】 Tree peony, originated from China, is one of the famous flowers in China and the central plains have always been the center for cultivating tree peonies. Cultivar Group of Tree Peony from Central Plains of China, which owns the most cultivars resources, has the longest history among all the cultivar groups. There were many researches on its cultivation and physiology, but a few on its genetic diversity, while the genetic diversity has not been revealed thoroughly. Since all the cultivars, which had not been screened by any modes, were preserved in the germplasm nursery gardens, not only farming land had been wasted but also the further studies and the effective applications been hindered. The studies on the construction of a core collection of Chinese tree peony cultivars and on its application will be an effective method to solve the problems above. According to the spot investigation and the descriptions in Pictorial Record of Chinese Tree Peony Varieties, genetic diversity and methodology establishing a core collection of the 400 tree peony cultivars from central plains were studied by combining the phenotypic data with the molecular data gained by ISSR and/or AFLP. The main results were as follows:1. Phenotypic database of 400 cultivars and the molecular database of the 120 cultivars in the primary core collection were firstly gained.2. Shannon index of the accessions was 0.9966 by analyzing on the phenotype genetic diversity. Shannon index for Single-flower section and Proliferate-flower section were 0.9688 and 0.8599, respectively. Among the 10 floral forms, Shannon index of crown form was the highest (0.9100), golden circle form, the lowest (0.313). The phenotypic traits, such as the length of leaf stalk, vertical and horizontal diameters of flower, leaf and flower color, were with higher Shannon index (>1) , while the Shannon indexes of other traitswere relatively lower. It was suggested that the genetic diversity of Chinese Central Plain Tree peony Cultivar Group should be enriched further.3. The sampling strategies to establish a core collection was firstly studied based the morphological database from the phenotypic traits of the 400 cultivars. The optimal methodology was that the primary core collection, which contained 30% samples of the accessions, should be constructed by means of defining the sampling number within each section by square root and drawing the samples by UPGMA cluster after grouping the accessions by floral form; the Core contained 15% samples of the accessions should be established at last based on minimizing the samples in the primary core by clustering to the phenotypic and molecular data.4. A primary core collection with 120 tree peony cultivars was constructed according to the optimal sampling strategy gained by our research. All the traits and component types of the primary core collection was the same as accessions according to the phenotypic analysis. The representation of Shannon index of the primary core collection to the one of accessions reached 99.12%. There were no significant differences on Shannon diversity indexes of the phenotypic traits between the primary core collection and accessions.5. A steady ISSR and AFLP reaction volumes were established based on the genomic DNA of all the 120 tree peony cultivars in the primary core collection. 244 DNA bands were amplified by 8 ISSR primers screened out from 83 ones, and 231 DNA bands (93.3%) among them were polymorphic. Mean of the PIC values of the 8 primers was 0.44. 1162 DNA bands were amplified by 8 AFLP pair primers screened out from 64 ones, and 1152 DNA bands (97.6%) among them were polymorphic. Mean of the PIC values of the 8 pair primers was 0.67. The rich genetic diversity of the primary core collection was proved further by the result of ISSR and AFLP markers.6. The Core composed of 60 cultivars was firstly established by the method of "phenotypic data + AFLP data + ISSR data", which had no significant difference with the primary core collection both on the phenotypic and DNA levels. Compared to the accessions, all the test indexes and the average genetic distance between the cultivars of the core collection were higher, and the 15% samples of the accessions were retained, aswell the RPR was 99% to the accessions.更多还原