Morphological characterization of the red dragon fruit - Selenicereus undatus (Haw.) D.R. Hunt – under growing conditions in the municipality of San Jerónimo (Antioquia, Colombia)

Abstract

The red dragon fruit Selenicereus undatus is a native fruit from the Americas. Its growing appeal in the international market as an exotic fruit highlights the relevance of the crop for the local economies. In Colombia, the high diversity within the genus and species makes it difficult to have reliable materials for propagation as cultivars. This agronomic challenge requires more studies of the distribution and real diversity within the genus Selenicereus sp. Due to the information aforementioned, the fruit is harvested in small localities as an extraction production system. This project aimed to morphologically characterize the working collection of red dragon fruit under growing conditions in the Municipality of San Jerónimo. It contained 30 accessions from the departments of Antioquia, Córdoba, and Valle del Cauca. Twenty-one characters of cladode, flower, and fruit were quantified to assess the diversity, and a restricted cluster analysis was performed to understand the morphological richness of the materials. As a result, it was observed differences in terms of stems, such as distance between areolas and width of cladode. This was also observed in flowers, in which their total length, the width of petals, the presence of trichomes, the color of calyx and petals, and the color of the stigma were different. Also, differences were recorded in the fruit. Characteristics such as weight and color of its skin were assessed, resulting in fruit size medium to small. Regarding other properties, total soluble solids varied between 11.2 to 15.6 °Brix. 55% of the fruits have measurements that fit market requirements. Finally, three accessions match the requirements of weight and °Brix, to be used as possible genotypes by commercial growers; however, studies about agronomic management strategies that favor an increase in fruit weight must be done.