【作者】 嵇怡；

【导师】 陈学好；

【作者基本信息】 扬州大学 ， 蔬菜学， 2008， 硕士

【摘要】 黄瓜(Cucumis sativus L.)是葫芦科重要成员之一,是世界上继番茄、白菜和洋葱之后的第四大被广泛种植的蔬菜作物。株高是黄瓜重要的农艺性状之一,黄瓜品种按植株高矮分为蔓生品种和矮生品种两大类型,在生产中应用的主要是蔓生黄瓜品种,但矮生黄瓜具有株型紧凑,无须整枝,能充分利用土地和光照资源,适于进行简易覆盖设施栽培,在各类设施栽培中可成倍提高种植密度,且只需简易的搭架和吊绳,在很大程度上节省了人力、物力和财力,其特殊的优势在生产中具有一定的应用前景。因此,培育植株高度适宜的“理想株型”正引起黄瓜育种家的关注。本研究以矮生黄瓜与蔓生黄瓜为试验材料,运用性状遗传体系分析方法对黄瓜株高性状进行遗传分析。以黄瓜矮生品系D8与蔓生品系JIN5杂交并自交得到的F2代为试材,应用ISSR分子标记技术和BSA(混合群体分组分析法)法寻找与黄瓜矮生基因连锁的分子标记。采用ISSR和SRAP的分子标记方法构建黄瓜遗传连锁图谱,利用复合区间定位方法对黄瓜矮生性状、第一雌花开花期等数量性状基因座(QTL)进行定位。研究的主要结果如下:1.以矮生黄瓜D8和蔓生黄瓜JIN5杂交并自交及回交所获得的6个世代(P1、P2、F1、BC1、BC2和F2)为材料,利用主基因+多基因混合遗传模型对黄瓜株高性状进行了遗传分析。结果表明:黄瓜株高受1对加性-显性主基因+加性-显性多基因共同控制,其中以主基因遗传为主,因此,在黄瓜育种实践中在早世代对株高选择有效。2.以黄瓜矮生品系D8与蔓生品系JIN5为亲本构建分离群体,应用ISSR分子标记技术和BSA(混合群体分组分析法)法寻找与黄瓜矮生基因连锁的分子标记,从100条ISSR引物中筛选到一条与黄瓜矮生性状相关的多态性引物UBC818,连锁关系分析表明,该标记与黄瓜矮生基因间的遗传距离为11.1cM。根据对该片段的序列分析结果重新设计了1对引物,将ISSR标记成功转化成了SCAR标记,并命名为UBC818-S。此SCAR标记可以在黄瓜苗期快速、准确、简便地鉴别出长矮生植株,从而为黄瓜矮生性状的分子标记辅助育种奠定了技术基础。3.应用ISSR和SRAP分子标记技术,构建了全长831.6cM的黄瓜分子遗传连锁图谱,标记平均间距为12.7cM,其中标记间最小遗传距离为4.8cM,最大遗传距离为22.3cM。运用WinQTLCart2.5软件,采用复合区间作图(CIM)法对黄瓜株高、第一雌花开花期等进行了QTL定位,检测到控制黄瓜株高性状的QTL位点2个,黄瓜平均节间距的QTL位点1个,第一雌花开花期的QTL位点7个。本研究的结果和检测到的QTL为进一步进行黄瓜株型育种的研究奠定了良好的基础。更多还原

【Abstract】 Cucumber (Cucumis sativus L.) is one of Cucubitaceae, which collectively belongs to a group of vegetables known as cucurbits and stands the fourth place followed by tomato,Chinese cabbage and onion. The plant height is one of important agriculture characters. Cucumber can be divided into two types.One has a long vine and the other short vine called dwarf type.Different vine types of cucumber might meet the need of the development of protected cultivation.The dwarf cucumber is easy to be cultivated in greenhouse since it is cost saving through cancelling a kickstand and increasing plant density. Tthe special superiority of dwarf cucumber has the broad application prospect in the production. Therefore, cucumber breeders are attaching importance to the breeding of new cucumber variety with reasonable plant height.Genetic analysis for cucumber plant height has been carried out with the method of quantitive traits heredity mode by using the commix model of main gene and multiple genes. F2 population from the cross combination of the dwarf line D8 and the vine line JIN5 were used in this study to screen the molecular marker related to the dwarf gene of cucumber with ISSR marker and BSA(bulked segregation analysis) method. A molecular linkage map was constructed with ISSR and SRAP marker. QTL ananlysis of plant height, flowering date of first female flower and the resistance to powdery mildew was performed with composite interval mapping(CIM). The main results are as followe:1. Six generations of P1 P2 F1 BC1 BC2 and F2 from the cross of dwarf line D8 and vine line JIN5 of cucumber were obtained to analyze the genetic effects of plant height by method mentioned above. Results indicate that the heredity of plant height could be explained by an additive-dominance major genes and additive-dominance polygene model ,and mainly by the main gene. In cucumber breeding, the selection in early generations may be effective.2. The F2 population from the cross between dwarf line D8 and vine line JIN5 was employed to screen the molecular marker related to the dwarf gene of cucumber with ISSR marker and BSA(bulked segregation analysis) method. UBC818, one out of eighty ISSR primers, was screened to present polymophism specified in the dwarf line. Genetic analysis showed that the genetic distance between the specific marker and cucumber dwarf gene was 11.1 cM. Two primers were designed based on the sequence to transform ISSR marker into SCAR marker. The ISSR marker was successfully converted into a SCAR marker named UBC818-S. This SCAR marker could distinguish the vine plant and dwarf plant accurately, easily and time saving, which provided a scientific basis of the marker-assisted breeding for dwarf cucumber.3. A genetic linkage map containing ISSR and SRAP markers was constructed, spanning a total of 831.6cM with an average interval of 12.7cM. The minimum heredity distance is 4.8cM, the maximum heredity distance is 22.3 cM. With the method of composite interval mapping and WinQTLCart2.5 software, two QTLs of plant height were examined, one QTL of the average distance nodes was identified. Moreover, seven QTLs of flowering date of first female flower were located.The QTL found in this study could provide useful information for future breeding of the plant height in cucumber.更多还原