Agro-morphological characterization of yellow passion fruit (Passiflora edulis f. flavicarpa Degener) reveals elite genotypes for a breeding program in Colombia

Yellow passion fruit cultivation in Colombia lacks detailed genetic studies that allow the establishment of intraspecific variability as a basis for a breeding program. The aim of this research was to establish the genetic relationships among accessions of different geographic origins through an agro-morphological characterization. This research was carried out in the municipality of Palestina (Caldas) at the Luker farm located at 1050 m a.s.l. Fifty-two accessions from Colombia (47), Ecuador (3), Brazil (1), and Costa Rica (1) were characterized with 45 agro-morphological descriptors complemented with phytosanitary evaluations. The quantitative descriptors (25) were analyzed by variance decomposition and principal components (PCA), and the qualitative descriptors (18) were analyzed with the multiple correspondence factor analysis (MCFA). The classification analysis by the neighbor-joining (NJ) method was used for both types of descriptors. PCA results showed six components explaining 71.6% of the total variance that are mainly associated with descriptors related to the size of the flower (tube, nectar camera, and operculum) and weight of the fruit (pulp, shell, and juice content). Thirteen qualitative descriptors were selected, and four factors (44.38% inertia) were identified, mainly associated with pubescence and anthocyanins in the bract, petiole, leaf, and ripe fruit color. The NJ classification analysis showed no relationship between accessions by geographic origin, and the distance between individuals of the same accession was higher than among accessions for both types of descriptors. Thrips (Neohydatothrips signifier) and scab (Cladosporium cladosporioides) were the pests with the highest incidence in the accessions. Six elite accessions were identified according to the selection index with outstanding fruit quality characteristics, yield, and tolerance to phytosanitary problems. The high intra-accession variability and traits of certain accessions are the basis for future breeding programs to obtain more productive and tolerant cultivars.