Agro-morphological characterization of robusta genotypes from the INERA Yangambi coffee collection, DRC

Robrecht Bollen; Jean-Léon Kambale; An-Sofie Tas; Benjamin Ntumba Katshela; Ebele Aaron Tshimi; Francis Wyffels; Filip Vandelook; Olivier Honnay; Piet Stoffelen

doi:10.25186/.v20i.2379

Authors

Robrecht Bollen Meise Botanic Garden, Department of Research. Meise, Belgium. https://orcid.org/0009-0007-0214-3151
Jean-Léon Kambale University of Kisangani, Kisangani, Democratic Republic of the Congo, Kisangani, Democratic Republic of the Congo. https://orcid.org/0000-0001-9092-5813
An-Sofie Tas Meise Botanic Garden, Department of Research. Meise, Belgium. https://orcid.org/0000-0001-9349-5361
Benjamin Ntumba Katshela University of Kisangani, Kisangani, Democratic Republic of the Congo, Kisangani, Democratic Republic of the Congo. https://orcid.org/0009-0005-1548-4057
Ebele Aaron Tshimi Institut National pour l’Etude et la Recherche Agronomiques/INERA, Yangambi, Democratic Republic of the Congo. https://orcid.org/0009-0004-7388-5652
Francis Wyffels IDLab-AIRO, ELIS Department, Ghent University – imec, 9052 Gent, Belgium. https://orcid.org/0000-0002-5491-8349
Filip Vandelook Meise Botanic Garden, Department of Research. Meise, Belgium. https://orcid.org/0000-0003-4591-5557
Olivier Honnay Leuven Plant Institute, 3001 Leuven, Belgium. https://orcid.org/0000-0002-4287-8511
Piet Stoffelen Meise Botanic Garden, Department of Research. Meise, Belgium. https://orcid.org/0000-0003-2547-0415

DOI:

https://doi.org/10.25186/.v20i.2379

Abstract

Meeting rising quality standards while at the same time addressing climate challenges will make the commercial cultivation of Robusta coffee increasingly difficult. Whereas breeding new varieties may be an important part of the solution, such efforts for Robusta lag behind, with much of its genetic diversity still unexplored. By screening existing field genebanks to identify accessions with desirable traits, breeding programs can be significantly facilitated. This study quantifies the morphological diversity and agronomic potential of 70 genotypes from the INERA Coffee Collection in Yangambi, Democratic Republic of the Congo. We measured 29 traits, comprising vegetative, reproductive, tree architecture, and yield traits. Classification models were applied to establish whether these traits could accurately classify genotypes based on their background. Furthermore, the agronomic potential and green bean quality of the genotypes were studied. While significant variation in morphological traits was observed, no combination of traits could reliably predict the genetic background of different genotypes. Genotypes with promising traits for green beans were identified in both ‘Lula’ and ‘Lula’ – Wild hybrids, while promising yield traits were found in ‘Lula’ – Congolese subgroup A hybrids. Additionally, certain ‘Lula’ – Wild hybrids showed low specific leaf area and stomatal density, indicating potential fitness advantages in dry environments, warranting further study. Our findings highlight the agronomic potential of underexplored Robusta coffee genotypes from the Democratic Republic of the Congo and indicate the need for further screening to maximize their value.

Key words: Coffea canephora; germplasm; phenotyping; coffee quality.

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Agro-morphological characterization of robusta genotypes from the INERA Yangambi coffee collection, DRC

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