Rice grain quality is a multifarious attribute mainly governed by multiple nutritional factors. Grain protein is the central component of rice grain nutrition dominantly affecting eating–cooking qualities. Grain protein content is quantitatively influenced by its protein fractions. Genetic quantification of five protein fractions—albumins, globulins, prolamins, glutelin, and grain protein content—were evaluated by exploiting two BC₃F₂ mapping populations, derived from Kongyu131/TKM9 (population-I) and Kongyu131/Bg94-1 (population-II), which were grown in a single environment. Correlation studies among protein fractions and grain protein content were thoroughly investigated. A genetic linkage map was developed by using 146 single sequence repeat (SSR) markers in population-I and 167 markers in population-II. In total, 40 QTLs were delineated for five traits in both populations. Approximately 22 QTLs were dissected in population-I, derived from Kongyu131/TKM9, seven QTLs for albumin content, four QTLs for globulin content, three QTLs for prolamin content, four QTLs for glutelin content, and four QTLs for grain protein content. In total, 18 QTLs were detected in population-II, derived from Kongyu131/Bg94-1, five QTLs for albumin content, three QTLs for globulin content, four QTLs for prolamin content, two QTLs for glutelin content, and four QTLs for grain protein content. Three QTLs, qAlb7.1, Alb7.2, and qGPC7.2, derived from population-II (Kongyu131/Bg94-1) for albumin and grain protein content were successfully validated in the near isogenic line (NIL) populations. The localized chromosomal locus of the validated QTLs could be helpful for fine mapping via map-based cloning to discover underlying candidate genes. The functional insights of the underlying candidate gene would furnish novel perceptivity for the foundation of rice grain protein content and trigger the development of nutritionally important rice cultivars by combining marker-assisted selection (MAS) breeding.

稻米品质是一个复杂的属性，主要受多种营养因素的影响。谷物蛋白质是大米谷物营养的核心成分，主要影响食用烹饪品质。谷物蛋白质含量在数量上受其蛋白质组分的影响。通过利用两个 BC ₃ F ₂作图群体（源自 Kongyu131/TKM9（群体 I）和 Kongyu131/Bg94-1（群体-II），在单一环境中生长。对蛋白质组分和谷物蛋白质含量之间的相关性研究进行了深入研究。利用群体 I 中的 146 个单序列重复 (SSR) 标记和群体 II 中的 167 个标记绘制了遗传连锁图谱。两个种群的五个性状总共有 40 个 QTL。在群体 I 中分析了大约 22 个 QTL，源自 Kongyu131/TKM9，其中 7 个用于白蛋白含量的 QTL、4 个用于球蛋白含量的 QTL、3 个用于谷醇溶蛋白含量的 QTL、4 个用于谷蛋白含量的 QTL 和 4 个用于谷物蛋白含量的 QTL。群体II中总共检测到18个QTL，来自Kongyu131/Bg94-1，其中白蛋白含量QTL 5个，球蛋白含量QTL 3个，谷醇溶蛋白含量QTL 4个，谷蛋白含量QTL 2个，谷物蛋白含量QTL 4个。内容。来自群体II (Kongyu131/Bg94-1)的白蛋白和谷物蛋白含量的三个QTL，qAlb7.1、Alb7.2和qGPC7.2在近等基因系(NIL)群体中被成功验证。经验证的 QTL 的局部染色体位点有助于通过基于图谱的克隆进行精细定位，以发现潜在的候选基因。潜在候选基因的功能见解将为水稻籽粒蛋白质含量的基础提供新的认识，并通过结合标记辅助选择（MAS）育种触发营养重要的水稻品种的开发。