Table2_QTL mapping of almond kernel quality traits in the F1 progeny of ‘Marcona’ × ‘Marinada’.docx

Almond breeding is increasingly focusing on kernel quality. However, unlike other agronomic traits, the genetic basis of physical and chemical kernel quality traits has been poorly investigated. To address this gap, we conducted a QTL mapping of these traits to enhance our understanding of their genetic control. We phenotyped fruit samples from an F1 population derived from the cross between ‘Marcona’ and ‘Marinada’ for up to four years, using conventional and image analysis methods. Additionally, the 91 individuals of the population were genotyped with the almond Axiom™ 60K SNP array, and high-density linkage maps were constructed. These analyses identified several genomic regions of breeding interest. For example, two regions on chromosome one were found to contain QTLs for kernel shape and dimension, while another region at the end of the same chromosome contained QTLs for kernel fatty acid composition. Notably, QTLs for kernel symmetry and kernel shoulder, reported for the first time in this study, were also mapped on chromosome one. These QTLs will serve as a foundation for developing molecular markers linked to kernel physical and chemical quality traits in almonds, facilitating the integration of marker-assisted selection into breeding programs.

扁桃育种日益侧重果仁品质。然而与其他农艺性状不同，果仁理化品质性状的遗传基础研究仍较为匮乏。为填补这一研究空白，本研究针对这些性状开展QTL（Quantitative Trait Locus，数量性状基因座）定位分析，以加深对其遗传调控机制的理解。本研究采用传统检测与图像分析相结合的方法，对以‘Marcona’与‘Marinada’杂交获得的F1群体的果实样本进行了长达四年的表型鉴定。此外，本研究利用扁桃Axiom™ 60K SNP（Single Nucleotide Polymorphism，单核苷酸多态性）芯片对该群体的91个个体进行了基因分型，并构建了高密度遗传连锁图谱。通过上述分析，本研究鉴定出多个与育种相关的基因组区域。例如，1号染色体上的两个区域分别存在调控果仁形状与尺寸的QTL，而同一条染色体末端的另一区域则包含调控果仁脂肪酸组成的QTL。值得注意的是，本研究首次报道了调控果仁对称性与果仁肩部性状的QTL，这些QTL同样定位在1号染色体上。这些QTL将为开发与扁桃果仁理化品质性状连锁的分子标记奠定基础，有助于将标记辅助选择技术整合到扁桃育种程序中。