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

What are crops?

Crops are plants that are cultivated and harvested for commercial purposes and use by humans. They can be grown for food, medicine, fuel, fibre, raw materials or for their chemical properties.

About crops

The domestication of wild plants for food began over 10,000 years ago in southwest Asia. Today, there are around 7,000 species of food crop, but just 12 of these account for around 80% of our calorie intake. More surprisingly, the three major cereal crops, rice, wheat and maize, account for roughly 50% of our calorie intake.

Crops and plants

All common crops have their origins in wild plant species. Some are almost indistinguishable from their humble ancestors, while others have been bred into wonderful new forms. Did you know for example that cabbage, kale, broccoli, cauliflower and Brussels sprouts have all been bred from wild cabbage, and so all belong to the same species Brassica oleracea? In this case, food producers have used different aspects of the genetic diversity of wild cabbage to develop the wonderful variety of forms we see today.

Agriculture and breeding plants

These days very little of the original genetic diversity found in the wild plant relatives of common crops remain, because food producers have selectively bred plants to have one or two main traits. Although commercial food crops have been developed and perfected to cater for human tastes and changing environmental conditions, this lack of genetic diversity often leaves them vulnerable to pests, disease and changes in climate.

It is estimated that 75% of the genetic diversity offered by the wild plant relatives of common crops has been lost in the development of just a few commercial food crops. It is this dependence on a small number of crops that threatens the future of global food security.

Wild carrots and food security


Photo Wild carrot (Daucus carota) in flower
Wild carrot (Daucus carota) in flower

The beautiful array of diversity in cultivated carrot varieties is not replicated on our supermarket shelves, but these alternative forms hold different tastes, textures and nutritional values. Wild carrots hold even greater genetic diversity and may be able to adapt more readily to future climates and be more resistant to pests and diseases. This story is the same for many other vegetables and their wild plant relatives.

The traits available in the wild plant relatives of commercial crops are therefore a vital resource for achieving global food security and developing a more sustainable approach to agriculture.

Kew's work safeguarding the wild relatives of common crops 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.