Evaluation of phenotypic variability in rocoto pepper (Capsicum pubescens Ruiz & Pav.) accessions from the national germplasm bank of INIA, Peru

Delgado-Lazo A.; Taco-Huancara D.; Dadther-Huaman H.; Hilari-Hilari M.C.; Pacheco-Lizárraga G. · Tropical and Subtropical Agroecosystems (2026) · DOI: 10.56369/tsaes.6637

Resumen

Background: Rocoto (Capsicum pubescens Ruiz & Pav.) is a domesticated species of the Capsicum genus with growing economic interest due to its recent entry into diverse international markets. Objective: To evaluate the phenotypic variability of 261 accessions from the rocoto pepper collection of the Germplasm Bank of the National Institute of Agrarian Innovation (INIA), preserved at the Arequipa Agricultural Experimental Station. Methodology: A total of 261 accessions were characterized using 52 agromorphological descriptors (37 qualitative and 15 quantitative). For the qualitative descriptors, the Shannon–Weaver index and multiple correspondence analysis were applied. The quantitative traits were analyzed using Pearson correlation analysis, principal component analysis, and hierarchical clustering. Results: The qualitative descriptors with the highest diversity were associated with fruit traits, mainly fruit color in the mature state, fruit shape and fruit shape in conjunction with the pedicel. Among the quantitative traits, fruit weight, fruit width, fruit wall thickness, and placenta diameter were the main contributors to variability. Multivariate analyses (PCA and hierarchical clustering) showed that the collection was structured into two main groups, differentiated by vegetative vigor and fruit development characteristics, confirming that fruit traits are the main factors of differentiation among accessions. Implications: This study highlights the phenotypic variability present in the rocoto pepper collection. The results provide useful information for identifying accessions with differentiated agronomic traits, facilitating decision-making in germplasm characterization and conservation processes. Conclusions: The INIA rocoto pepper germplasm collection exhibits high phenotypic variability, mainly determined by fruit traits, which represent the primary criteria for differentiation among accessions. This variability evidence morphological divergence within the collection and represents a solid basis for the selection of promising materials and for the development of breeding and conservation programs of C. pubescens. Copyright © the authors. Work licensed under a CC-BY 4.0 License. https://creativecommons.org/licenses/by/4.0/