Variability in Morpho-Physiological and Fruit Traits of Aristotelia chilensis [Molina] Stuntz Genotypes Across Two Contrasting Sites: Insight for the Species’ Domestication and Cultivar Selection

Berry fruits from Aristotelia chilensis (Molina) Stuntz are considered a “superfruit” because of their high antioxidant activity. Currently, most traded berries are wildcrafted from natural populations, threatening the resource’s sustainability, but some efforts are underway to domesticate the species, which may be very versatile in agroforestry and orchard systems. We assessed genotypic variability and stability of ecophysiological and fruit-related traits in A. chilensis clones established at two contrasting sites of northern-central (Panguilemo) and southern (Panguipulli) Chile. At both sites, we measured clones for growth, leaf morpho-physiological, and fruit traits seven years after planting. Overall, there was a significant genotype–environment interaction (G × E) for foliar area (FA) and fruit dry mass (FDM), mainly explained by the higher performance of some clones in the most fertile site at Panguilemo than at Panguipulli. Intrinsic water use efficiency (WUEint) was higher at the drier northern site (+79%) than in Panguipulli, while at the genotype level, it was higher in southern-origin clones. Clonal variation was observed in anthocyanin content (five-fold between the highest and lowest value), but not in polyphenol content. In Panguilemo, FDM was positively correlated with FA but tended to be negatively related to WUEint, indicating a disadvantageous trade-off for future selection. Relationships between gas exchange, twig growth, and fruit traits decoupled at Panguipulli, likely associated with the mild weather. Despite the low number of clones and sites tested, this study provides guidelines for future genotype and trait selection. Deploying orchards with selected clones can reduce pressure on wild populations, contributing to the sustainability of this resource.