Molecular Characterization of Natural Populations of Macleania rupestris (Kunth) in Southern Ecuador: Relationships Between Morphological Traits and Total Phenolic Content

Macleania rupestris is an underutilized wild fruit-bearing shrub native to the Ecuadorian Andes, with considerable ecological importance and potential for sustainable local development. However, information regarding its genetic, morphological, and phytochemical diversity remains scarce. This study aimed to characterize the genetic and morphological diversity and total phenolic content (TPC) of M. rupestris populations. A multilocus analysis was performed using three previously amplified concatenated sequences. Fruit characterization was conducted using quantitative morphological and physicochemical traits, while TPC was expressed as gallic acid equivalents and determined in fruits collected from the same individuals. Relationships among genetic, fruit, phytochemical, and environmental variables were also explored. The multilocus phylogenetic structure showed no clear geographic pattern, while most fruit traits exhibited limited differentiation among provinces. However, soluble solids content (°Brix), seed number, and pedicel length differed significantly among provinces. Fruit moisture content was moderately negatively correlated with soluble solids content (r = −0.45) and moderately positively correlated with seed number (r = 0.46). These correlations represent observational associations and do not demonstrate causal relationships. No significant correlation was detected between fruit traits and TPC. These findings provide important scientific basis for the conservation, selection of promising genotypes, and future domestication of this underutilized Andean fruit species.