One day last March I talked with Juliana and Elisa, a mother and daughter who farmed just outside the city of Huánuco, Peru. Although they had only one acre of land in this mountainous landscape, they grew dozens of local varieties of potatoes and corn, along with other crops. And they knew each of their varieties by a common name – mostly in their Quechua language.
Potatoes are native to the Andes, and over 4,000 varieties are grown there now. They come in numerous shapes, sizes and colors – red, yellow, purple, striped and spotted. A colorful mound of them resembles the bold, burnished colors of locally woven shawls.
This wide array of types is an example of agrobiodiversity – a genetic legacy created by natural selection interacting with cultural practices over thousands of years. Today, however, agrobiodiversity is declining in many countries. In Mexico farmers are cultivating only 20 percent of the corn types that were grown there in 1930. Chinese farmers are producing only 10 percent of 10,000 varieties of wheat that were recorded there in 1949. More than 95 percent of known apple varieties that existed in the United States in 1900 are no longer cultivated.
According to Bioversity International, an international research and policy organization, just three crops – rice, wheat and maize – provide more than half of plant-derived calories consumed worldwide. This is a problem because our diets are heavy in calories, sugar and saturated fat and low in fruits and vegetables.
But there also are bright spots, such as Andean potatoes. In a recent article, Stef de Haan of the International Center for Tropical Agriculture and I call for a major effort to strengthen agrobiodiversity for the future. Consuming many different species and varieties provides a diet that offers many unique tastes and a wide selection of nutrients that humans need to thrive. It also can help ensure more stable food systems and the needed variety of desirable genetic traits, such as hardiness.