Green coffee beans, derived from the plant genus Coffea, are the world’s most traded agricultural product after oil. This commodity supports the livelihoods of over 120 million people globally. However, the crop faces unprecedented environmental and biological threats that challenge its commercial viability due to global climate shifts.
The Primary Threats to Global Coffee Production
The largest driver affecting coffee plants is climate change, which disrupts the narrow environmental band required for optimal growth. Rising temperatures push the ideal growing zone to higher altitudes, while altered rainfall patterns lead to droughts or excessive rain, stressing the delicate coffee plants. For example, every one-degree Celsius rise in temperature in East Africa is linked to a 14 to 27 percent decrease in crop yields.
Warmer conditions fuel the proliferation of biological threats, creating a more hospitable environment for pests and diseases. The fungal disease Coffee Leaf Rust (Hemileia vastatrix) thrives in wet, warm conditions. This fungus attacks the leaves, leading to defoliation, reduced photosynthesis, and a significant drop in yield and quality.
The Coffee Berry Borer (CBB) (Hypothenemus hampei) is a beetle that causes millions in losses annually by boring into the coffee cherry. Warmer temperatures accelerate the insect’s life cycle and allow it to expand its range to higher elevations where it was previously controlled by cooler climates. The combination of climate stress and increased pest and disease pressure creates a cycle of reduced plant health and diminished harvests.
Vulnerable Species and Extinction Projections
The two commercially grown species, Coffea arabica (Arabica) and Coffea canephora (Robusta), show very different levels of vulnerability to the current threats. Arabica, which accounts for about 60% of global production, is far more susceptible because it requires a narrow temperature range of 15–24°C and thrives at high altitudes. Temperatures above this optimal range cause plant stress, resulting in premature fruit ripening and poor bean quality.
Robusta, conversely, is more resilient, tolerating higher temperatures between 22–28°C and thriving at lower altitudes. However, even this hardier species is not immune, as key Robusta-producing regions like Vietnam have faced severe droughts and unpredictable rainfall patterns. The primary concern remains the commercial viability of Arabica, the preferred bean for its complex flavor profile.
Scientific modeling projects a drastic reduction in suitable growing land within the coming decades. Under current climate trajectories, the global area suitable for coffee production is projected to be reduced by half by 2050. The timeline for the loss of wild coffee species is even more dire, with projections suggesting that wild Coffea varieties, a source of genetic diversity, could face extinction by 2080.
This commercial collapse is expected to hit specific geographic regions first, particularly those in the “Bean Belt”. Projections show that major Arabica-growing regions in Central America, such as Nicaragua, could become non-viable by 2050, while yields in East Africa, including Tanzania, could be critically low by 2060. This loss of suitability means that while the plant genus may not vanish entirely, widespread cultivation meeting global demand will become increasingly difficult.
Scientific Strategies for Coffee Conservation
A proactive approach to securing the future of coffee centers on leveraging genetic diversity, particularly through advanced breeding programs. Scientists are working to identify and incorporate desirable traits from wild coffee relatives into commercial varieties. This includes traits such as natural resistance to diseases like Coffee Leaf Rust and tolerance for higher temperatures and drought conditions.
The process of developing new varieties through classical breeding is slow, often taking more than fifteen years to release a new cultivar. Researchers are therefore utilizing modern techniques like genomics and marker-assisted selection to speed up the identification of valuable genes. This effort also involves exploring lesser-known wild species, such as Coffea stenophylla and Coffea liberica, which offer naturally greater resilience to climate stress.
Conservation efforts are a major pillar of the strategy, focusing on both ex situ (off-site) and in situ (on-site) preservation. Ex situ conservation involves maintaining gene banks and seed collections to safeguard the genetic material of the 124 known Coffea species. However, the current system of gene banks is often fragmented and requires significant upgrades and secure funding for long-term sustainability.
In situ conservation involves protecting the natural forest habitats where wild coffee species still grow, ensuring their continued evolution and survival within their native ecosystems. In parallel, farmers are adopting practical agricultural adaptations known as Climate-Smart Agriculture. This includes transitioning to shade-grown coffee, which utilizes a forest canopy to stabilize temperatures and reduce water stress on the plants.