【作者】 李瑞峰；

【导师】 栾非时；

【作者基本信息】 东北农业大学 ， 蔬菜学， 2014， 硕士

【摘要】 甜瓜是世界人民备受喜爱的水果型蔬菜,在我国农村经济中占有重要地位。随着改革开放的深入,国家对瓜果生产由计划经济改为产销放开、市场调节,这一政策全面促进了甜瓜产业的迅速发展。目前,新育成的甜瓜品种数在逐年增加,涌入市场的新品种不计其数。随着新育成品种的不断增加,骨干亲本的重复使用,新基因资源的缺乏,新育成品种的鉴定难度逐渐增大；加之当前国内甜瓜种子市场尚不够规范,一些单位受商业利益驱动篡改品种名称、盗用新育成品种名称,导致中国甜瓜市场品种普遍存在着由于同名异物或同物异名现象导致的品种真实性问题,各地出现由品种真实性引起的纠纷事件不断。为解决甜瓜新育成品种的鉴定问题与品种真实性引起的种子纠纷事件,急需建立我国甜瓜品种的核酸指纹库,为品种纯度与真实性鉴定提供技术支撑。本试验收集了235个国内甜瓜主栽品种,采用形态学标记和SSR标记技术,分别从形态特性及遗传物质的特异性两方面研究供试235个甜瓜品种的遗传多样性,并为235个甜瓜品种构建了指纹图谱库,为我国甜瓜公共指纹数据库的构建提供理论依据和技术支撑。采用形态学标记,观察的14个果实性状中,平均变异系数为0.17。其中芳香气变异系数最大,为0.46。基于对上述14个形态学性状的聚类分析,得到235个品种的聚类分析图,235个品种之间的遗传相似系数变幅为0.73-0.96。对60个品种二次聚类,相似系数为0.73-0.94,在相似系数为0.74处,60个甜瓜品种被分为2组,一组为13份厚皮甜瓜,另一组是46份薄皮甜瓜和1份厚皮甜瓜。利用18对引物,用于235个甜瓜品种的多样性分析,共得到5050条清晰可辨条带,其中多态性条带157条。每对引物可以检测到4-14条数目不等的多态性条带,平均为9条。多态性信息含量(PIC)平均为0.71,变化范围为0.57-0.87。所有供试品种由18对核心引物扩增得到的157个位点,对所有供试品种进行聚类分析。结果表明,品种间的相似系数变幅在0.69-0.99之间。对60个甜瓜供试品种进行二次聚类,构建了60个品种聚类分析图。图中可以看出所有供试品种遗传相似系数的变化范围在0.75-0.95之间。当相似系数在0.77时,可以将所有供试品种分为6类,包括来自不同地区的3类厚皮甜瓜和3类薄皮甜瓜,与形态学聚类分析结果基本一致,较形态学标记分类更为细致。235个甜瓜品种经过18对引物扩增后,每个品种建立自己的指纹图谱代码。比较每个品种建立的指纹代码,发现其中有26个品种指纹代码不唯一,这26个品种分为10组,每组里的品种指纹代码相同。26份指纹代码不唯一的品种占所有供试品种的12%,鉴别率达88%。利用QR精灵对5个品种进行编码,其中包含了品种的名称、来源地、果皮底色、果肉颜色、糖度、肉质、类型等直观性状及SSR分子标记的指纹图谱代码等信息,得到的二维码简洁方便,本试验提供了编码需要的所有信息,可以为每个品种构建了一份指纹图谱编码。更多还原

【Abstract】 Melon (Cucumis melo L.), is a very important horticultural crop worldwide which belonging to Cucumis, Cucurbitaceae. Furthermore, melon is also one important economic crop worldwide which plays a significant role in farmers’ income through melon produce. With the deepening of reform and opening up, the state of melon production quickly increases,the melon industry’s rapid development.At present, the phenomenon of homonym and synonyms in melon industry of our China are widespread, which could cause variety authenticity issues. Also, because of the unstrictness in breeding, processing, storage and other aspects, there are many seed quality problems, such as poor varietal purity. There are many reasons for these problems, and now the effects of these problems in melon production are tremendous. In order to solve the disputes and confusions in the market during the course of melon seed operating, it’s necessary to establish DNA fingerprint database of melon, which could provide technical supports for the identifications of varietal purity and authenticity. At the same time, as the second largest originating center of melon in the world, China owns rich melon material resources, so it’s important to enhance the basis study of melon and establish an information platform about the public melon germplasm genetic relationship. In this study,235melon from China melon market were employed to reveal their genetic diversity and morphological characters based on SSR markers. And The results were demonstrated as follows:In this study, the genetic diversity in235melon aceessions was assessed using14morphological descriptors. The morphological deseritors include7qualitative and7quantitative. The average coefficient variation was0.17. The morphological traits revealed the variance coefficent on melon aroma reached0.46. They ranged from0.02in covered veins on fruit rind and the color of covered veins to0.46based on7qualitative descriptors and from0.05in number of days after sowing to harvesting to0.24in weight of fruit based on the7quantitative descriptors.The result of morphological cluster analysis showed that the genetic similarity coefficient of the235accessions ranged from0.73-0.96.60materials were extracted for the second cluster analysis, and the similarity coefficients were between0.73-0.94, also, the test materials could be divided into2categories at the genetic similarity coefficient of0.74. The results indicated that based on morphological cluster analysis these melons could be classified into Cucumis melo ssp. conomon and C. melo ssp. melo.The genetie diversity in melon accessions by SSR.The results showed:SSR markers by18core primers were used to determine the frequence of DNA Polymorphism in melon germplasms. A total of157bands were detected among235melon accessions. Each pair of primers could detect4-14polymorphic bands, and the average were9bands. Also, the average of polymorphism information contents was0.71with the range of0.57-0.87. Based on157sites of18pairs of core primers, we obtained the cluster analysis pictures of235materials, with the similarity coefficients between0.69-0.99.60materials were extracted for the second cluster analysis, and the similarity coefficients were between0.75-0.95, also, the test materials could be divided into6categories at the genetic similarity coefficient of0.77.Based on the amplification of18pairs of primers, fingerprint codes for each material in235melon varieties were established, and there were10groups of materials with the same fingerprint, involving26materials that accounted for12%of the tested materials, and the identification rate reached88%.And the other accession had unique fingerprinting.Also, fingerprint QR codes of each material were constructed, including name, origin, color, type, quality, SSR fingerprint and更多还原