Diversidad morfológica y caracterización fenotípica de ecotipos de mora (Rubus spp.) en los Andes ecuatorianos (2037-2620 msnm)

Abstract

The blackberry (Rubus sp.) is a fruit crop of great socioeconomic importance in Ecuador. The limited information on the morphological diversity of local ecotypes hinders the development of genetic improvement and conservation programs. To characterize this diversity, sixteen ecotypes of the genus Rubus were recorded in situ at three sites in the Guaranda canton, Bolívar province (2037–2620 masl), belonging to the species R. glaucus, R. niveus, R. floribundus Kunth, R. ulmifolius Schott, and R. rosifolius Sm. Eighteen qualitative descriptors were evaluated using Multiple Correspondence Analysis (MCA) and Ward’s method with Euclidean distance. Discriminant analysis identified seven descriptors with the highest discriminatory power (CV > 35%): leaf shape (CV = 57.75%), fruiting habit (CV = 36.63%), apex shape (CV = 36.41%), corolla color (CV = 36.41%), leaf margin shape (CV = 35.40%), leaf pubescence (CV = 35.93%), and mature fruit shape (CV = 36.40%). MCA explained 82.61% of the total variability in two dimensions (D1 = 46.91%, α = 0.925; D2 = 35.71%, α = 0.880). The cluster analysis formed three groups: Cluster 1 grouped cultivated ecotypes of R. glaucus, Cluster 2 grouped the species R. floribundus Kunth and R. niveus Thunb., and Cluster 3 included R. ulmifolius Schott and R. rosifolius Sm. These findings provide a low-cost, preliminary morphological basis for guiding parent selection in Rubus conservation and breeding programs in the Ecuadorian Andes.