Kale Sandip M, Paina Cristiana, Füchtbauer Winnie S, Bjarup Pernille, Sarup Pernille Merete, Schatz-Jakobsen Janus Asbjørn, Orabi Jihad, Borum Finn, Jahoor Ahmed, Brinch-Pedersen Henrik
Crop Genetics and Biotechnology Section, Department of Agroecology, Aarhus University, Slagelse, Denmark.
Sejet Plant Breeding, Horsens, Denmark.
Plant Genome. 2025 Sep;18(3):e70090. doi: 10.1002/tpg2.70090.
Improving grain protein content (GPC) in wheat (Triticum aestivum L.) is crucial for enhancing end-use quality and ensuring efficient nitrogen (N) utilization, thereby reducing environmental damage caused by excess N. However, progress in increasing GPC has been limited because of the strong negative correlation between GPC and grain yield (GY), as well as the scarcity of multi-location, multi-year phenotypic data. In this study, we analyzed the variation in GPC, GY, and grain protein deviation (GPD) using multi-location, multi-year phenotypic data from winter wheat varieties in Scandinavian regions. As reported previously, we observed a negative correlation between GY and GPC, with recent cultivars showing higher GY but lower GPC. Additionally, a genome-wide association study (GWAS) in two independent populations identified significant marker-trait associations (MTAs) for GPC and GPD, with key MTAs located on chromosome 2B (chr2B), highlighting its central role in the regulation of these traits. Interestingly, the MTA for GPD on chr2B coincided with an introgression from Triticum timopheevii, which was associated with reduced GPC and GPD in elite lines carrying this region. This introgression, which contains a powdery mildew resistance gene (Pm6), appears to negatively affect GPC, likely due to linkage drag. These findings emphasize the importance of chr2B in wheat breeding and suggest that advanced genomic techniques, such as mutagenesis and CRISPR-Cas, could be employed to mitigate negative pleiotropic effects and improve GPC and GPD. Overall, this study provides valuable insights into the genetic architecture underlying GPC in wheat and offers directions for future breeding strategies aimed at enhancing protein content.
提高小麦（Triticum aestivum L.）的籽粒蛋白质含量（GPC）对于提升最终使用品质和确保高效氮（N）利用至关重要，从而减少过量氮对环境造成的损害。然而，由于GPC与籽粒产量（GY）之间存在强烈的负相关，以及缺乏多地点、多年的表型数据，提高GPC的进展有限。在本研究中，我们利用斯堪的纳维亚地区冬小麦品种的多地点、多年表型数据分析了GPC、GY和籽粒蛋白质偏差（GPD）的变异。如先前报道，我们观察到GY与GPC之间存在负相关，近期品种的GY较高但GPC较低。此外，在两个独立群体中进行的全基因组关联研究（GWAS）确定了GPC和GPD的显著标记-性状关联（MTA），关键MTA位于2B染色体（chr2B）上，突出了其在这些性状调控中的核心作用。有趣的是，chr2B上GPD的MTA与来自提莫菲维小麦的渐渗系重合，这与携带该区域的优良品系中GPC和GPD的降低有关。这个包含白粉病抗性基因（Pm6）的渐渗系似乎对GPC有负面影响，可能是由于连锁累赘。这些发现强调了chr2B在小麦育种中的重要性，并表明可以采用诱变和CRISPR-Cas等先进的基因组技术来减轻负向多效性影响并改善GPC和GPD。总体而言，本研究为小麦GPC的遗传结构提供了有价值的见解，并为未来旨在提高蛋白质含量的育种策略提供了方向。
