中文摘要：

【目的】西双版纳黄瓜是中国特有的黄瓜种质资源,有多心室特性。在探明西双版纳黄瓜多心室性状表现及遗传规律的基础上进行多心室QTL定位,为进一步了解其分子机理和标记辅助育种奠定基础,也为黄瓜果实性状改良提供有益参考和帮助。【方法】对‘北京截头’黄瓜（CC3,3心室）和西双版纳黄瓜（SWCC8,5心室）不同时期的子房进行石蜡切片观察;基于以‘北京截头’黄瓜和西双版纳黄瓜为亲本构建的含124个株系的F9代RIL群体,利用已完成的遗传图谱,结合两个季节的RIL群体心室数目统计结果进行多心室QTL定位分析。【结果】石蜡切片观察发现,西双版纳黄瓜子房由5个心皮内卷构成多心室的结构,与3心室黄瓜相比,其子房横径大且胎座数量多;QTL定位分析发现5个控制多心室性状的QTL（LOD〉2.5）,分别分布在1、2、6号染色体上,其中位于1号染色体上的QTL ln1.1和ln1.3在2013年秋季、2014年春季这两季统计结果中都稳定存在,ln1.1在两季的LOD值分别为10.96和9.24,贡献率分别为39.24%和20.49%,位于标记SSR16472—SSR12070。ln1.3在两季的LOD值分别为27.31和21.45,贡献率分别为75.90%和47.11%,位于标记UW083751—SSR04278,认为这两个位点是控制多心室的主效QTL,其余位点为微效位点。ln1.1区段的遗传距离为6.3 c M,物理距离为0.97 Mb,包含159个基因。ln1.3区段的遗传距离为4.9 c M,物理距离为2.07 Mb,包含227个基因。在ln1.1和ln1.3区段内分别预测了2个调控多心室性状的基因,包括2个WD40重复蛋白基因（Csa1M071910.1和Csa1M072490.1）和2个Aux/IAA生长素应答基因（Csa1M231530.1和Csa1M207820.1）。【结论】位于1号染色体上的ln1.1和ln1.3是控制多心室性状的主效QTL。预测2个参与植物激素信号转导的基因Csa1M207820.1和Csa1M231530.1,以及2个与WD40重复蛋白相关的基因Csa1M071910.1和Csa1M072490.1为候选基因。

英文摘要：

【Objective】Xishuangbanna cucumber（Cucumis sativus L. var. xishuangbannanesis Qi et Yuan） is an elite Chinese original cucumber germplasm that produces fruits with multi-locule-number, of which the diameter is much larger than the 3-locules fruit. The purpose of this study is to investigate the inheritance and QTL locations of the multi-locule-number trait in Xishuangbanna cucumber. The results of the study will provide a preliminary basis for further study on mechanism of multi-locule-number trait and molecular assistant selection breeding, they also can provide helpful information for improvement of fruit characters of cucumber.【Method】The ovaries of Beijingjietou cucumber（CC3, 3-locules） and Xishuangbanna cucumber（SWCC8, 5-locules） were harvested at different developmental stages for paraffin sections. According to the genetic linkage map constructed based on 124 F9 recombinant inbred lines（RILs） derived from the cross of Beijingjietou×Xishuangbanna, the multi-locule-number QTLs were analyzed with the locule number statistics of RILs population in two seasons. 【Result】 Histological observation showed that the ovary of Xishuangbanna cucumber is consisted with five involute carpels which formed the multi-locules. By comparing with 3-locules cucumber ovary, the 5-locules cucumber ovary has a larger diameter and more placentas. QTL analysis indicated that 5 QTLs（LOD〉2.5） distributed on chromosomes 1, 2, and 6. The major QTL ln1.1 locating between SSR16472-SSR12070 was detected in two seasons, having two LOD scores of 10.96, 9.24 and R2 of 39.24%, 20.49%, respectively. The another major QTL ln1.3 locating between UW083751-SSR04278 was detected in two seasons, having two LOD scores of 27.31 and 21.45, and R2 of 75.90% and 47.11%, respectively. The rest QTLs were minor QTLs. Combined with previous findings, there were two genes that control multi-locule-number in ln1.1 and ln1.3 regions, respectively. The two genes in ln1.1 region were WD40 repeat protein gene, Csa1M071910.1 and Csa1