Würschum Tobias, Boeven Philipp H G, Langer Simon M, Longin C Friedrich H, Leiser Willmar L
State Plant Breeding Institute, University of Hohenheim, 70593, Stuttgart, Germany.
Current address: Bayer CropScience Aktiengesellschaft, European Wheat Breeding Center, 06466, Gatersleben, Germany.
BMC Genet. 2015 Jul 29;16:96. doi: 10.1186/s12863-015-0258-0.
Copy number variation was found to be a frequent type of DNA polymorphism in the human genome often associated with diseases but its importance in crops and the effects on agronomic traits are still largely unknown.
Here, we employed a large worldwide panel of 1110 winter wheat varieties to assess the frequency and the geographic distribution of copy number variants at the Photoperiod-B1 (Ppd-B1) and the Vernalization-A1 (Vrn-A1) loci as well as their effects on flowering time under field conditions. We identified a novel four copy variant of Vrn-A1 and based on the phylogenetic relationships among the lines show that the higher copy variants at both loci are likely to have arisen independently multiple times. In addition, we found that the frequency of the different copy number variants at both loci reflects the environmental conditions in the varieties' region of origin and based on multi-location field trials show that Ppd-B1 copy number has a substantial effect on the fine-tuning of flowering time.
In conclusion, our results show the importance of copy number variation at Ppd-B1 and Vrn-A1 for the global adaptation of wheat making it a key factor for wheat success in a broad range of environments and in a wider context substantiate the significant role of copy number variation in crops.
拷贝数变异是人类基因组中常见的一种DNA多态性类型，常与疾病相关，但在作物中的重要性及其对农艺性状的影响仍 largely unknown。
在此，我们利用一个由1110个冬小麦品种组成的全球大型样本，评估光周期-B1（Ppd-B1）和春化-A1（Vrn-A1）位点拷贝数变异的频率和地理分布，以及它们在田间条件下对开花时间的影响。我们鉴定出一种新的Vrn-A1四拷贝变异体，并根据品系间的系统发育关系表明，两个位点的高拷贝变异体可能多次独立出现。此外，我们发现两个位点不同拷贝数变异体的频率反映了品种原产地的环境条件，并且基于多点田间试验表明，Ppd-B1拷贝数对开花时间的微调有显著影响。
总之，我们的结果表明Ppd-B1和Vrn-A1位点的拷贝数变异对小麦的全球适应性很重要，使其成为小麦在广泛环境中成功的关键因素，并且在更广泛的背景下证实了拷贝数变异在作物中的重要作用。
