Coffee, one of the most heavily globally traded agricultural commodities, has been categorized as a highly sensitive plant species to progressive climatic change. Here, we summarize recent insights on the coffee plant's physiological performance at elevated atmospheric carbon dioxide concentration [CO 2 ]. We specifically (i) provide new data of crop yields obtained under free-air CO 2 enrichment conditions, (ii) discuss predictions on the future of the coffee crop as based on rising temperature and (iii) emphasize the role of [CO 2 ] as a key player for mitigating harmful effects of supra-optimal temperatures on coffee physiology and bean quality. We conclude that the effects of global warming on the climatic suitability of coffee may be lower than previously assumed. We highlight perspectives and priorities for further Climatic Change (2019) 152:167-178 https://doi.# The Author(s) 2018research to improve our understanding on how the coffee plant will respond to present and progressive climate change.The current rise in atmospheric carbon dioxide concentration ([CO 2 ]) is one of the major drivers of global warming and climatic change. Atmospheric [CO 2 ] has increased approximately by 43% from the pre-industrial levels of 280 μL L −1 air in 1750 to current levels exceeding 400 μL L −1 air, and global mean surface temperature has increased by 0.85°C over the same period. Depending on the greenhouse gas emission scenarios, projections indicate that, at the end of this century, atmospheric [CO 2 ] might rise between 421 and 936 μL L −1 air, in parallel with a rise in global temperature between 0.3-1.7°C (best scenario) and 2.6-4.8°C (worst scenario), relative to 1986 (IPCC 2013 IPCC 2014). These long-term changes, coupled with climate variability, such as longer and unpredictable droughts and sometimes excessive rainfall, are expected to threaten the sustainability of agricultural production on a global scale, with consequences on the amount and quality of harvestable crops for the actual production areas (DaMatta et al. 2010).Plants sense and respond directly to rising atmospheric [CO 2 ] through an increase in net photosynthesis rate (A) and, frequently, a decrease in stomatal conductance (g s ), and this is the basis for the CO 2 fertilization effect on crops with corresponding increase in yields (Long et al. 2006;Ainsworth and Rogers 2007). Meta-analyses of free-air CO 2 enhancement (FACE) experiments have reported mean reductions in g s of 22% and increases in light-saturated (A) of 31% across a range of C 3 species for an increase in [CO 2 ] from approximately 366 to 567 μL L −1 air (Ainsworth and Rogers 2007). Increases in A with enhanced [CO 2 ] in the chloroplast of C3 plants are associated with a stimulation of the carboxylation rate of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), the rate-limiting step in photosynthesis at saturating light and current [CO 2 ] levels, and a concomitant reduction (or even suppression) of its oxygenation function, and thus the rate of photorespiration (Ainsw...

There are worldwide approximately 4.3 million coffee (Coffea arabica) producing smallholders generating a large share of tropical developing countries' gross domestic product, notably in Central America. Their livelihoods and coffee production are facing

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