Coffee varieties

Coffee varieties are the diverse subspecies derived through selective breeding or natural selection of coffee plants. While there is tremendous variability encountered in both wild and cultivated coffee plants, there are a few varieties and cultivars that are commercially important due to various unique and inherent traits such as disease resistance and fruit yield. These unique traits are what producers use to select breeds when developing crops. Therefore, at a micro level, breed selection is critical to the success of a producer and is one of the key components of cup quality.

At a macro level, the viability of the coffee industry as a whole is dependent upon breed selection. Already, the majority of coffee produced originates from producers using selected breeds. For this reason, breed selection is an important aspect of sustainability within coffee production.

There is considerable confusion as to which term to use when speaking about coffee subspecies. For the sake of clarity, within this article the terms will be used in accordance with loose guidelines put forth by the Specialty Coffee Association of America:

Variety: This rank of taxa delineates differences between plants that are smaller than in subspecies but larger than forms. A variety retains most of the characteristics of the species, but differs in some way.
Cultivar: Any variety produced by horticultural or agricultural techniques and not normally found in natural populations; a cultivated variety. Most of the varieties we know in specialty coffee are really cultivars. Bourbon and Typica are some of the most widely known cultivars.

Put simply: In this article, varieties are naturally occurring subspecies and cultivars are cultivated subspecies. In addition, a third term, "breed" will be used as an umbrella term to simplify discussions in which the nuances between the terms 'variety' and 'cultivar' have no bearing.

Before the end of the 19th century, arabica was indeed the exclusive producer of all coffee in the world but the first documented outbreak of coffee leaf rust (CLR) disease decimated crops around the world, prompting many farmers to explore alternative crops.

While some countries almost completely replaced coffee production with alternative crops, Indonesia began introducing robusta, which has both a high yield in fruit and a high level of resistance to CLR. Unfortunately, robusta also produces lower quality coffee. During the first half of the 20th century, East Java pioneered systematic breeding designs on robusta coffee, which would become "exemplary to all subsequent breeding programmes of robusta coffee in India and Africa." This knowledge of robusta is critical for modern coffee breeding because robusta is the main source of pest and disease traits not found in arabica.

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Wikipedia