Climate Hazards and the Changing World of Coffee Pests and Diseases in Sub-Saharan Africa

Abstract

Coffee has over the years remained of great importance to the global economy. Although the crop originated from Africa, its production is presently dominated by Brazil and Vietnam, which now respectively account for 34 and 13% of global production. Ethiopia and Uganda which are at the fore-front of production within sub-Saharan Africa account for 62% of the region’s coffee output. Out of the many species of coffee that exist, C. arabica (Arabica coffee) and C. canephora (Robusta coffee) are of outstanding economic importance. While the former does well on high altitudes (1000-2000 m above sea level), average temperature ranges of between 15 and 24°C, and 2000 mm rainfall per annum, the latter, which can thrive under hotter, drier conditions can be grown on altitudes of about 800 m above sea level.  Generally speaking, optimal coffee-growing conditions include cool to warm tropical climates, rich soils, and few pests or diseases. Each of the grown species however does well under specific environmental conditions. The constantly increasing environmental temperatures, coupled with accompanying variations in weather conditions, have some direct debilitating effects on coffee production and quality. Pests and pathogens, being able to tolerate a wide range of temperature, have the capabilities to proliferate and negatively influence the crop’s yield, quality and production cost. In view of the the highlighted problems, some mitigation strategies have been developed by researchers to limit the extent of damage caused by global warming on coffee production in the region. Chief among these include genetic improvement/development of resistant cultivars, reforestation (planting under shade), high-density planting/irrigation, integrated pest management, improved access to climate information and reduction of green house gas emissions. These, among others would enhance the quantity and quality of coffee produced and consequently boost the region’s economy.