Deciphering leaf morpho-biochemical and mineral diversity in strawberry tree (Arbutus andrachne L.) genotypes through multivariate statistical approaches

Strawberry tree ( Arbutus andrachne L.) leaves represent a sustainable source of bioactive compounds and mineral nutrients with considerable potential for pharmaceutical, nutraceutical, and functional food applications. However, comprehensive information integrating leaf morphology, biochemical characteristics, mineral composition, and multivariate statistical analyses remains limited. This study aimed to characterize the leaf morpho-biochemical and mineral diversity of 30 naturally growing strawberry tree genotypes collected from Hatay, Türkiye, and to identify phenotypically promising plant materials for future evaluation in breeding, domestication, and industrial leaf biomass production. The evaluated variables were analyzed using Pearson correlation analysis, principal component analysis (PCA), hierarchical cluster analysis (HCA), heat map analysis (HMA), and multiple regression analysis (MRA). Leaf width, leaf length, petiole length, and petiole thickness ranged from 24.92 (‘ST-2’) to 54.28 mm (‘ST-5’), 45.48 (‘ST-28’) to 91.74 mm (‘ST-12’), 8.14 (‘ST-10’) to 23.14 mm (‘ST-29’), and 0.78 (‘ST-28’) to 1.72 mm (‘ST-16’), respectively. Total phenolic content, total flavonoid content, and antioxidant activity ranged from 53.95 (‘ST-13’) to 74.89 mg GAE 100 g⁻¹ FW (‘ST-2’), 13.59 (‘ST-26’) to 35.12 mg CAE 100 g⁻¹ FW (‘ST-7’), and 32.00% (‘ST-17’) to 64.50% (‘ST-13’), respectively. Calcium was the predominant mineral element, ranging from 5327.22 mg kg⁻¹ DW (‘ST-10’) to 27352.35 mg kg⁻¹ DW (‘ST-28’), followed by phosphorus and potassium. Pearson correlation analysis revealed strong positive associations among leaf morphological traits and among most mineral elements, whereas MRA showed that leaf width was primarily explained by leaf length ( R² = 0.95). In contrast, magnesium was identified as a significant predictor of phenolic and flavonoid contents, while both magnesium and potassium were significant predictors of antioxidant activity. PCA extracted six principal components, jointly explaining 79.62% of the total variation, confirming substantial multidimensional diversity among genotypes. Collectively, the results identified ‘ST-5’ and ‘ST-12’ for superior leaf morphology, ‘ST-2’, ‘ST-7’, and ‘ST-13’ for outstanding bioactive properties, and ‘ST-28’ for exceptional calcium accumulation as phenotypically promising plant materials for further evaluation in breeding, conservation, domestication, and sustainable industrial utilization of strawberry tree leaf biomass.