甜瓜属包括黄瓜和甜瓜两种重要栽培作物，以及非洲角黄瓜、酸黄瓜等多种携带重要抗性基因的近缘种。物种间存在不同程度的杂交不亲和性或杂种染色体组间的重组抑制，阻碍了近缘物种间优异基因的转移利用。染色体结构的差异是造成其生殖隔离或重组障碍的重要因素。本项目研究旨在揭示甜瓜属物种间染色体结构分化特征，为野生资源优异基因的转移利用提供理论指导。物种间染色体涂染的比较分析能直观地反映近缘物种间的染色体重排、区段重复/缺失等结构的差异。项目将基于申请者前期开发的单拷贝基因染色体涂染技术，利用黄瓜和甜瓜全基因组的注释基因，研究特定染色体探针在甜瓜属主要物种染色体上的同源分布，分析物种间染色体的重排特征，构建黄瓜、甜瓜、非洲角黄瓜、酸黄瓜等甜瓜属主要物种间的比较染色体图谱，深入系统分析甜瓜属物种的染色体结构分化特征。预期结果有助于指导甜瓜属种质资源的利用，并为葫芦科作物的进化提供重要理论基础。

Cucumis genus includes two economically important crops, cucumber (C. sativus L.) and melon (C. melo L.), and other wild species as well, such as C. metuliferus L., and C. hystrix Chakr. which carry important resistant genes. The utilization of useful genes from wild species for crop improvement has been hampered due to the extensive cross-incompatible among most of cucumis species, or the severe recombination suppression between parental chromosomes in the interspecific hybrid. The structural differentiation of chromosome among species could explain these obstacles. This research aims at elucidating the characterization of structure differentiation of chromosomes in cucumis, which could provide theoretical guidance for the introgression breeding. Comparative chromosome painting allows the direct visualization of chromosome structure differentiation, like chromosome rearrangements, duplication/deletion, etc. In this research, single copy gene chromosome painting technology (ScgCP) will be employed to investigate the structure differentiation of chromosome in cucumis. The annotated genes from cucumber and melon genomes will be used for designing chromosome-specific probes. Comparative chromosome painting method will be carried out to detect the homogenous regions among the different species from cucumis. Based on the analysis, the comparative chromosome maps will be constructed, and the structure differentiation of chromosomes of cucumis species will be revealed. The expected results will be helpful for guiding the introduction of useful genes from wild relatives into cultivars based on interspecific hybridization, and provide the basis for elucidating the evolution of Cucurbitaceae species as well.