4.6. Conclusion and implications
Considering climate change and its adverse effects on coffee production, this study showed that Uganda has potentially adapted C. canephora genetic diversity which could be used to develop drought-tolerant genotypes. Breeders, however, need to work towards weakening or even breaking the trade-off between drought tolerance and performance. As noted by Borrell et al., (2020) the conservation of extant genetic diversity, particularly in a period of rapid environmental change is critical to support future crop improvement. In this regard, the Zoka population is of special interest among the wholeC. canephora natural distribution in Africa, being within the drier end of the climatic gradient and exhibiting relatively high drought tolerance. Zoka is a small unique forest (the only tropical rainforest occurring in dry northern Uganda), but its small size (12.6 km2) makes the population particularly vulnerable to habitat destruction. At a national level, there is a need to foster thein-situ conservation and management of Uganda’s C. canephora wild populations. Strategic in-situ conservation of these wild populations will allow for their evolution and adaptation to environmental stresses and consequently the continued use of the material to offer resilience to cultivated C. canephora material amidst the escalating effects of climate change. National conservation strategies should involve the restriction of C. canephoracultivation near any wild population to deter genetic drift and to allow continuous adaptation of the natural populations.
DATA ACCESSIBILITY STATEMENT
Data associated with this manuscript is included and will be archived in the Dryad data repository.
COMPETING INTERESTS STATEMENT
None declared
AUTHOR CONTRIBUTIONS
Catherine Kiwuka : Conceptualization, methodology, formal analysis, investigation, data curation, writing—original draft preparation, project administration, funding acquisition. Jan Vos : Conceptualization, methodology, data curation, formal analysis, visualization, writing—review and editing, supervision. Jacob C. Douma : Data curation, formal analysis, visualization, writing—review and editing. Pascal Musoli : Conceptualization, methodology resources, writing—review and editing, supervision.John W. Mulumba : Conceptualization, methodology, writing—review and editing, supervision. Valérie Poncet : Conceptualization, methodology, formal analysis, writing—review and editing, supervision. Niels P.R. Anten : conceptualization, methodology, formal analysis, visualization, resources, writing—review and editing, supervision.
FUNDING
The activities of this study were mainly funded by the World Bank-supported project entitled ”Agricultural Technology and Agribusiness Advisory Services” (ATAAS) through National Agricultural Research Organization (NARO). Additionally, we thank the Uganda Coffee Development Authority (UCDA) for additional financial assistance to support the experimental phase of the study.
ACKNOWLEDGMENTS
This study was conducted under the auspices of the Centre for Crop Systems Analysis (CSA) of the Production Ecology and Resource Conservation Graduate School of Wageningen University and Research and the National Agricultural Research Organization (NARO) of Uganda. We thank the National Forestry Authority (NFA; NFA/N/9.2/14) and the Uganda Wildlife Authority (UWA; EDO/35/01) for permitting us to collect the study samples. We are grateful to the director of research of the National Agricultural Research Laboratories (NARL), Kawanda; Dr Tushemereirwe Wilberforce and the administration team for logistical support. Special thanks to the devoted research assistance team comprising: M. Lumu, H. Were, S. Katende, W. O. Maganyi, R. Sekasamba, D. Nasaazi, J. Makya, F. Okoda, E. Oluput, I. Makya, D. Kasoozi, R. Kakooto and S. Kiconco Stella. We appreciate the Agropolis Foundation - CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) for partially supporting the molecular characterisation of the studied genotypes. We also acknowledge support from Dr Alexandre de Kochko and Dr Aaron P. Davis.
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APPENDICES
Appendix A