Brassica napus L. is the third most cultivated oil crop in the world. Flowering time is one of the important agronomic traits that affecting crop yield. In this study, we constructed an early flowering near-isogenic line (NIL) NZ-A2, by using an early flowering accession NO.2127 as donor parent and a late flowering accession ZY821 as recurrent parent. Two QTLs, qFTA2.1a and qFTA2.1b, were detected in the A02 chromosome of B. napus, which accounting for 25.4% and 49.1% of the total flowering time variations, respectively. Further fine mapping of the qFTA2.1a delimited it in a chromosome interval with a physic distance of 245 Kb, in which an important flowering gene BnaFT.A2 was identified. The NIL contained the qFTA2.1a locus flowered about 7 days earlier than the late flowering parent ZY821. Thus, this QTL is of great significant to B. napus breeding for varieties with superior maturity.

欧洲油菜是世界上种植面积第三大的油料作物。花期是影响作物产量的重要农艺性状之一。在本研究中，我们构建了早花近等基因系 (NIL) NZ-A2，使用早花种质 NO.2127 作为供体亲本，使用晚花种质 ZY821 作为轮回亲本。在欧洲油菜A02染色体上检测到两个QTL，qFTA2.1a和qFTA2.1b，分别占总开花时间变异的25.4%和49.1%。qFTA2.1a 的进一步精细定位将其限定在物理距离为 245 Kb 的染色体间隔中，其中一个重要的开花基因BnaFT.A2被识别。NIL 包含比晚花亲本 ZY821 早约 7 天开花的 qFTA2.1a 基因座。因此，该QTL对欧洲油菜选育成熟度较高的品种具有重要意义。