有棱丝瓜和普通丝瓜的日开花时间相差近12小时，花期隔离阻碍了二者间的基因流动，促进了种群分化。为了探明这一机制的遗传基础，我们的前期工作对丝瓜的转录组进行了测序，通过序列分析成功开发了8523对EST-SSR标记；同时将有棱丝瓜S304和普通丝瓜P93075杂交，培育了一个F2遗传群体，利用新开发的分子标记，构建了一张包含170个标记的遗传图谱，并对丝瓜日开花时间性状进行了QTL初步定位。本项目拟在此基础上，选择主效QTL作为研究目标，通过回交、自交培育目标QTL区段的近等基因系，作为精细定位群体；同时构建丝瓜基因组BAC文库，筛选包含目标区段的BAC克隆，对其测序开发分子标记，利用这些标记和精细定位群体，对目标QTL进行精细定位。通过本项目的实施，一方面有助于从进化上揭示普通丝瓜和有棱丝瓜的种群分化机制；另一方面能够为下一步克隆目标QTL、打破种间花期隔离、利用丝瓜种间杂种优势打下基础。

The difference of daily flowering time between L.acutangula Roxb. and L.cylindrica Roem. is nearly 12 hours, which has a passive impact on the gene flow between them. In order to understand the genetic basis of this phenomenon, the transcriptome sequencing of sponge gourd was carried out in the preliminary project stage, successfully developing 8,523 pairs of EST-SSR markers. Meanwhile, F2 Population was derived from the cross breeding between S304 (L.acutangula) and P93075 (L.cylindrica), a genetic linkage map consisting of 170 EST-SSR markers was provided, and the primary QTL mapping was conducted for the daily flowering time trait of sponge gourd . On the basis of these studies, this research aims to select a major QTL to develop QTL-NIL (near-isogenic line, NIL) for fine mapping by means of repeated backcross and self cross. At the meantime, the genomic BAC libraries will be constructed for sponge gourd, and BAC cloning including target regions will be screened. By means of the molecular markers developed by sequencing BAC cloning, coupled with QTL-NIL, fine mapping of QTL will be conducted. This research is supposed to reveal the mechanism of population differentiation in sponge gourd, and also form the basis of following target QTL cloning, and contribute to eliminating the difference of daily flowering time between L.acutangula Roxb. and L.cylindrica Roem. and the application of interspecific hybrid advantage in sponge gourd.