Variation analysis of growth traits and medicinal components in different provenances of Polygonatum cyrtonema based on heterogeneous garden experiment.

Abstract

Polygonatum cyrtonema is a valuable medicinal and edible plant whose sustainable utilization is challenged by wild resource depletion and germplasm degradation. This study established a multi-site provenance trial across three heterogeneous garden environments in Zhejiang Province, China, to evaluate 11 geographically diverse provenances. We systematically measured growth traits (plant height, stem diameter, leaf morphology) and medicinal components (polysaccharides, saponins, flavonoids, total phenolics), and applied combined ANOVA, correlation analysis, principal component analysis, and cluster analysis to quantify provenance variation patterns and environmental drivers. Results revealed highly significant differences (P < 0.01) among provenances, sites, and their interactions for all traits. Substantial phenotypic (PCV: 7.41%-46.89%) and genotypic (GCV: 5.99%-44.92%) coefficients of variation were observed, with particularly high variation in polysaccharides and key growth traits, coupled with substantial provenance repeatability (0.63-0.99), indicated strong potential for selective breeding. Correlation analysis showed significant positive associations between growth traits and key medicinal components. Geo-climatic analysis identified distinct environmental drivers: saponin content increased with altitude and temperature, while flavonoid accumulation was promoted in drier conditions. Based on principal component analysis (cumulative contribution: 85.20%), Songyang (3.34) and Yunhe (2.98) provenances achieved the highest comprehensive evaluation scores. Cluster analysis further classified the provenances into three groups, with Songyang and Yunhe forming a distinct cluster characterized by superior growth and medicinal compound accumulation. These provenances are recommended as elite materials for breeding programs. This study provides a scientific basis for the selective breeding of P. cyrtonema and holds significant practical implications for enhancing the quality and efficiency of the understory economy and promoting the sustainable use of medicinal plant resources.