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