Conventional American cultivars of coffee are no longer adapted to global warming. Finding highly productive and stable cultivars in different environments without neglecting quality characteristics has become a priority for breeders. In this study, new Arabica F1 hybrids clones were compared to conventional American varieties in seven contrasting environments, for yield, rust incidence and volume of the canopy. The quality was assessed through size, weight of 100 beans, biochemical analysis (24 aroma precursors and 31 volatiles compounds) and sensory analysis. Conventional varieties were the least productive, producing 50% less than the best hybrid. The AMMI model analysis pointed out five hybrids as the most stable and productive. Two F1 hybrids clones, H1-Centroamericano and H16-Mundo Maya, were superior to the most planted American cultivar in Latin and Central America showing a high yield performance and stability performance. H1-Centroamerica and Starmaya contain more D-limonene than Caturra, while Starmaya contain more 3-methylbutanoic acid than the control. Those two latter volatiles compounds are linked with good cup quality in previous studies. In terms of sensory analysis, Starmaya and H1-Centroamericano scored better than control.

In the present paper, we evaluated the implementation of a seed production system based on the exploitation of male sterility on coffee. We studied specifically the combination between CIR-SM01 and Marsellesa® (a Sarchimor line), which provides a hybrid population called Starmaya. We demonstrated that the establishment of seed garden under natural pollination is possible and produces a sufficient amount of hybrid seeds to be multiplied efficiently and economically. As expected for F1 hybrid, the performances of Starmaya are highly superior to conventional cultivars. However, we observed some heterogeneity on Starmaya cultivar in the field. We confirmed by genetic marker analysis that the off-types were partly related to the heterozygosity of the CIR-SM01 clone and could not be modified. Regarding the level of rust resistance of Starmaya cv., we saw that it could be improved if Marsellesa was more fully fixed genetically. If so, we should be able to decrease significantly the percentage of rust incidence of Starmaya from 15 to 5%, which would be quite acceptable at a commercial level. Starmaya represents the proof of concept for the mass propagation of Arabica F1 hybrid seeds using male sterility. Finally, we discuss the possibility to increase the number of hybrid varieties produced by seed, exploring some initiatives to identify male sterility markers to induce male sterility on any conventional cultivar. This would definitively open up the universe of known Arabica cultivars to be used in breeding new F1 hybrids.

Coffee is deemed to be a high-risk crop in light of upcoming climate changes. Agroforestry practices have been proposed as a nature-based strategy for coffee farmers to mitigate and adapt to future climates. However, with agroforestry systems comes shade, a highly contentious factor for coffee production in terms of potential yield reduction, as well as additional management needs and interactions between shade trees and pest and disease. In this review, we summarize recent research relating to the effects of shade on (i) farmers' use and perceptions, (ii) the coffee microenvironment, (iii) pest and disease incidence, (iv) carbon assimilation and phenology of coffee plants, (v) coffee quality attributes (evaluated by coffee bean size, biochemical compounds, and cup quality tests), (vi) breeding of new Arabica coffee F1 hybrids and Robusta clones for future agroforestry systems, and (vii) coffee production under climate change. Through this work, we begin to decipher whether shaded systems are a feasible strategy to improve the coffee crop sustainability in anticipation of challenging climate conditions. Further research is proposed for developing new coffee varieties adapted to agroforestry systems (exhibiting traits suitable for climate stressors), refining extension tools by selecting locally-adapted shade trees species and developing policy and economic incentives enabling the adoption of sustainable agroforestry practices.

The coffee research community has maintained a long ongoing debate regarding the implications of shade trees in coffee production. Historically, there has been contrasting results and opinions on this matter, thus recommendations for the use of shade (namely in coffee agroforestry systems) are often deemed controversial, particularly due to potential yield declines and farmers’ income. This study is one of the first demonstrating how several Coffea arabica cultivars respond differently to shade with respect to yield. By standardising more than 200 coffee yield data from various in-field trials, we assembled the so-called “Ristretto” data pool, a one of a kind, open-source dataset, consolidating decades of coffee yield data under shaded systems. With this standardised dataset, our meta-analysis demonstrated significant genotypic heterogeneity in response to shade, showing neutral, inverted U-shaped and decreasing trends between yield and shade cover amongst 18 different cultivars. These findings encourage the examination of C. arabica at the cultivar level when assessing suitability for agroforestry systems. Comparison of productivity is also encouraged across a range of low to moderate shade levels (10–40%), in order to help elucidate potential unknown optimal shade levels for coffee production.

Cocoa cultivation is labeled as a driver of both deforestation and reforestation, yet the extent of the phenomena varies at farm and landscape level and as a response to national and local contexts. In this study, we documented the main pathways and contexts behind cocoa cultivation in two sites with different histories of cocoa cultivation. We combined official statistics, land-use trajectory, satellite imagery, and the Q-analysis to explore the discourses of country experts in Nicaragua and Peru. The Q-statements were based on an analysis of a set of legal, institutional, social, and technical guidelines that the cocoa cultivation/sector influences or is influenced by. Based on the responses of national experts to 31 statements we found four discourses linking cocoa cultivation and reforestation and deforestation in each country-case study. The enabling and limiting conditions driving tree cover change were a combination of landscape configuration, governance, management/commercialization models, and farmer's knowledge. Overall, between 60 and 64% of the variance was explained by four discourse factors in each country. In Nicaragua, the conditions associated with reforestation were the cocoa-agroforestry model promoted by local organizations/NGOs, the existence of incentives, degree of technical knowledge, access to safe market, and availability of improved genetic material. The circumstances associated with deforestation were the age of the farmers, fluctuation of cocoa beans prices, low productivity of cocoa plantations, and weak legal environmental frameworks. Whereas, in Peru, the main factors connecting cocoa cultivation to reforestation were access to market, degree of experimentation in cocoa, the economic weight of cocoa on family's income, certification processes, the existence of incentives, and the level of organization/association of cocoa farmers. The elements linking cocoa farming to deforestation were the influence of stakeholders in the cocoa value chain, weak legal environmental frameworks, fluctuation of cocoa prices, the existence of private investors, and insecure land tenure rights. This article demonstrated the utility of discourse analysis, through its application to two contrasting country case-studies, to elucidate the conditions that might minimize the deforestation footprint of cocoa cultivation and maximize its role as an agent for reforestation/restoration in the agricultural landscape of cocoa-growing areas in Latin America.