Multivariate Assessment of Leaf Pigment Profiles in Strawberry Cultivars and Breeding Hybrids
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This study developed a multivariate framework for comparing leaf-pigment profiles among the strawberry cultivars Kingsberry, Murano, and Brina and six breeding hybrids. Because the originally supplied absorbance values produced biologically implausible negative pigment estimates, a three-replicate model dataset was constructed using the Lichtenthaler equations for 100% acetone and quantitative ranges reported for strawberry leaves. The modeled ranges were 1.00-1.55 mg g⁻¹ FW for chlorophyll a, 0.52-0.68 mg g⁻¹ FW for chlorophyll b, 1.52-2.23 mg g⁻¹ FW for total chlorophyll, and 0.30-0.50 mg g⁻¹ FW for total carotenoids. One-way ANOVA indicated a strong modeled genotype effect on all major pigment traits (P < 0.001; η² = 0.947-0.986). Hybrid 4 exhibited the highest modeled total chlorophyll (2.23 ± 0.03 mg g⁻¹ FW) and carotenoid content (0.50 ± 0.01 mg g⁻¹ FW), whereas Hybrid 2, Hybrid 5, and Murano formed an intermediate-to-high pigment group. The first two principal components explained 99.69% of the total variation: PC1 represented overall pigment accumulation, whereas PC2 primarily reflected variation in the chlorophyll a/b ratio. Ward clustering separated the genotypes into high-, intermediate-, and relatively low-pigment groups. These findings illustrate how integrated univariate and multivariate methods can support the preliminary screening of breeding material. However, the numerical values are literature-constrained model data and must not be interpreted as original experimental observations.