Mitigation of the Negative Impact of Warming on the Coffee Crop: The Role of Increased Air [CO2] and Management Strategies

Abstract

Crop sustainability can be threatened by new environmental challenges regarding predicted climate changes and global warming. Therefore, the study of real biological impacts of future environmental conditions (e.g., increased air [CO 2 ], supra-optimal temperature and water scarcity) on crop plants, as well as the re-evaluation of management procedures and strategies, must be undertaken in order to improve crop adaptation and promote mitigation of negative environmental impacts, thus affording crop resilience. Coffee is a tropical crop that is grown in more than 80 countries, making it one of the world's most traded agricultural products, while involving millions of people worldwide in the whole chain of value. It has been argued that this crop will be highly affected by climate changes, resulting in decreases in both suitable areas for cultivation and productivity, as well as impaired beverage quality in the near future. Here, we report recent findings regarding coffee species exposure to combined supra-optimal air temperatures and enhanced air [CO 2 ], and impacts of drought stress on the crop. Ultimately, we discuss key strategies to improve coffee performance in the context of new environmental scenarios. The recent findings clearly show that high [CO 2 ] has a positive impact on coffee plants, increasing their tolerance to high temperatures. This has been related to a better

Resilient and Sensitive Key Points of the Photosynthetic Machinery of Coffea spp. to the Single and Superimposed Exposure to Severe Drought and Heat Stresses

“…In contrast, PSI photoinhibition can be mostly promoted by ROS produced on the receptor side of PSI through the Mehler reaction (Sonoike, 2011;Yan et al, 2013). PSI is often considered to be more resistant to photoinhibition through an efficient scavenging of ROS produced on the reducing side of PSI (Ozakca, 2013). In any case, under the present experimental conditions, PSI and PSII were affected to a similar extent within each genotype by drought (only CL153), by heat, or even by the stress combination, suggesting that thermal dissipation and/or antioxidative mechanisms protected both PSs indistinctly.…”

Impact of drought associated with high temperatures on Coffea canephora plantations: a case study in Espírito Santo State, Brazil

“…On the other hand, drought-resistant genotypes can be benefited because they generally show reduction of yield under optimal environments conditions. This happens for such genotypes due to the increase of sensitivity of their stomata to VPD 75 . Thereby, these authors concluded that coffee genotypes displaying increased phenotypic plasticity (e.g., deep root system, substantial hydraulic conductance, intermediate stomatal control and strengthening of antioxidant defense system) could be used in regions which are predicted to face moderate water deficit, while drought-resistant genotypes could be used in regions predicted to face severe drought.…”

Intrinsic non-stomatal resilience to drought of the photosynthetic apparatus in Coffea spp. is strengthened by elevated air [CO2]

“…Nonetheless, another growing concern is associated with water scarcity (DaMatta et al 2018, Ramalho et al 2018b given that coffee is cultivated in tropical areas, which are expected to be strongly impacted by climate change (IPCC 2018). Drought (and heat) impacts are additionally expected to be aggravated, particularly in coffee plantations under full sunlight exposure, which will impose new management challenges to afford sustainability for the coffee crop (Dubberstein et al 2018.…”