Skip to main content
You are here
Facebook icon
Pinterest icon
Twitter icon

Crops and their wild plant relatives

Crop wild relatives are wild species closely related to common food crops. These wild cousins of crops are vital to food security because they contain greater amounts of genetic diversity, making them more resilient in the face of climate change, pests and diseases and other new threats.
Kew released a study warning that, due to the effects of climate change, Arabica coffee could be extinct by the end of 21st century.
Seventy per cent of global coffee production comes from Arabica coffee

Coffee under threat

Coffee, one of the world's best loved beverages, is under threat. Of the 125 species of wild coffee, only two are used in commercial production, Arabica coffee (Coffea arabica) and Robusta coffee (C. cenophora).


This video discusses the origins of Arabica coffee, and what Kew is doing to help safeguard its future

Seventy per cent of global coffee production comes from Arabica coffee and commercial plantations contain only a tiny fraction (around 1%) of the diversity in the wild populations. Scientists at Kew, in collaboration with the Ethiopian Environment and Coffee Forest Forum (ECFF), have published a study modelling the effects of climate predictions on wild coffee populations and the suitable area for coffee growth is predicted to shrink rapidly.

Climate change is already affecting the survival and yields of coffee crops in some parts of the world and the plants will come under increasing stress as temperatures rise, making them susceptible to pests and diseases. Based on predictions, almost two thirds of all localities with the right climate for wild Arabica coffee growth could disappear by 2080 and wild coffee populations in south Sudan could disappear entirely by 2020. We will need to look towards the genetic diversity held in the 125 species of wild coffee, to help us overcome future challenges in coffee production. This work emphasises the need to conserve wild forests - the storehouses of useful genetic diversity.

A race against time

It is a race against time to safeguard the wild relatives of food crops before they disappear. For example, Solanum ruvu, a wild relative of aubergine, was collected for the first time in Tanzania in 2000 and by the time it had been identified as a new plant species, its native habitat had been destroyed. Further attempts to find it have also failed so Solanum ruvu is now likely to be extinct, and any useful traits contained in this plant species, such as salt tolerance, pest resistance and disease resistance, have been lost.


Detail of Solanum ruvu specimen
Detail of Solanum ruvu specimen collected by B. Mhoro and the Frontier-Tanzania Programme in the Ruvu Forest Reserve. This is the only collection known of this species, and one of the only two herbarium specimens known.

There may be other wild plant relatives of common crops that we don’t yet know about, or that become extinct before we learn how they might be useful to us. Kew’s conservation work around the world helps to conserve wild plant species in their natural environment and also safeguards their seed in Kew's Millennium Seed Bank, to ensure these useful plant species are not lost to us forever

Safeguarding food plants for our future

At Kew, as part of the Adapting Agriculture to Climate Change project, work has begun to collect seed from the wild plant relatives of 29 common crop plants whose genetic diversity can be used to breed new and useful traits into commercial crops so they can better adapt to future climates and other threats, such as pests and diseases. The crops we are focusing on include apple, banana, barley, butter bean, carrot, chickpea, aubergine (eggplant), lentil, oat, pea, potato, rice, rye, sunflower, sweet potato and bread wheat.

Kew's work offers a concrete step towards strengthening global food security for our future. Support Kew's work today and help us reduce the threats facing the world's food supply.