Department of Nematology, University of California, Riverside, CA, USA.
College of Science and Engineering, Flinders University, Bedford Park, SA, Australia.
Sci Rep. 2024 Feb 25;14(1):4567. doi: 10.1038/s41598-024-55214-2.
Development of high yielding cowpea varieties coupled with good taste and rich in essential minerals can promote consumption and thus nutrition and profitability. The sweet taste of cowpea grain is determined by its sugar content, which comprises mainly sucrose and galacto-oligosaccharides (GOS) including raffinose and stachyose. However, GOS are indigestible and their fermentation in the colon can produce excess intestinal gas, causing undesirable bloating and flatulence. In this study, we aimed to examine variation in grain sugar and mineral concentrations, then map quantitative trait loci (QTLs) and estimate genomic-prediction (GP) accuracies for possible application in breeding. Grain samples were collected from a multi-parent advanced generation intercross (MAGIC) population grown in California during 2016-2017. Grain sugars were assayed using high-performance liquid chromatography. Grain minerals were determined by inductively coupled plasma-optical emission spectrometry and combustion. Considerable variation was observed for sucrose (0.6-6.9%) and stachyose (2.3-8.4%). Major QTLs for sucrose (QSuc.vu-1.1), stachyose (QSta.vu-7.1), copper (QCu.vu-1.1) and manganese (QMn.vu-5.1) were identified. Allelic effects of major sugar QTLs were validated using the MAGIC grain samples grown in West Africa in 2017. GP accuracies for minerals were moderate (0.4-0.58). These findings help guide future breeding efforts to develop mineral-rich cowpea varieties with desirable sugar content.
培育高产、口感好且富含必需矿物质的豇豆品种可以促进消费，从而提高营养和盈利能力。豇豆籽粒的甜味取决于其含糖量，主要由蔗糖和半乳糖低聚糖（GOS）组成，包括棉子糖和水苏糖。然而，GOS 是不可消化的，它们在结肠中的发酵会产生过多的肠道气体，导致令人不快的腹胀和胀气。在这项研究中，我们旨在研究籽粒糖和矿物质浓度的变化，然后绘制数量性状位点（QTL）图谱，并估计基因组预测（GP）的准确性，以便在育种中应用。籽粒样品采集自 2016-2017 年在加利福尼亚种植的多亲本高级世代互交（MAGIC）群体。使用高效液相色谱法测定籽粒糖，电感耦合等离子体-光学发射光谱法和燃烧法测定籽粒矿物质。蔗糖（0.6-6.9%）和水苏糖（2.3-8.4%）的变化较大。蔗糖（QSuc.vu-1.1）、水苏糖（QSta.vu-7.1）、铜（QCu.vu-1.1）和锰（QMn.vu-5.1）的主要 QTL 被鉴定出来。使用 2017 年在西非种植的 MAGIC 籽粒样品验证了主要糖 QTL 的等位基因效应。矿物质的 GP 准确性为中等（0.4-0.58）。这些发现有助于指导未来的育种工作，以开发具有理想含糖量的富含矿物质的豇豆品种。
