Integrative evaluation of traits and metabolomics in germplasm resources of the high-calcium crop Primulina eburnea

Germplasm evaluation is the first step in the utilization and domestication of wild plant resources. Despite the increasing recognition of Primulina eburnea as a valuable plant-based resource for industrial calcium supplement production, systematic evaluation of its germplasm resources remains limited. This study assessed the diversity of 37 wild P. eburnea populations through common-garden experiments, analyzing 26 quality-related traits. Significant variation was found in phenotypic and nutrient traits, with mean coefficients of variation above 20 %, indicating potential for improvement. Phenotypic differentiation coefficient analysis showed that 54.52 % of the total variation was attributable to differences among populations. Principal component analysis and cluster analysis classified the populations into two distinct groups, corresponding to their eastern and western geographical distributions. Correlation analysis identified 95 significant trait relationships, enabling efficient germplasm selection. Environmental factor analysis showed that geographic isolation, which leads to differences in light, rainfall, and temperature, was a key driver of trait differentiation. The membership function models, outperforming PCA in balancing trait selection and genetic diversity, was used to establish a core germplasm bank of 13 populations. Metabolomic profiling further revealed significant differences between eastern and western populations, particularly in flavonoids and phenolic acids, which are potentially linked to bioactivity and medicinal properties. These findings support the robustness of the evaluation model and the reliability of the established core germplasm collection. Overall, these results provide a solid evaluation framework and a reliable core germplasm collection, supporting breeding, large-scale cultivation, and industrial development of P. eburnea as a high-calcium crop. • Primulina eburnea exhibits rich trait variations due to population differences. • The 37 populations were divided into 2 clusters with clear geographic patterns. • Light, rainfall, and temperature variations likely drove trait differentiation in P. eburnea. • Metabolomic profiling revealed bioactive compounds and region-specific metabolic patterns in P. eburnea . • A core germplasm collection was established using the membership function method.