Foragers learn to separate the delicious wild plants from the deadly ones.
Foragers learn to separate the delicious wild plants from the deadly ones.

Many wild relatives of important food crops, which could be used to help those crops adapt and thrive in an environment impacted by climate change, are missing from the world's genebanks.

Researchers with the Adapting Agriculture to Climate Change project mapped more than 1,000 crop wild relatives (CWR) of rice, potato, maize, wheat and 77 other important crops, and found significant gaps in the species that have been collected, and the geographic regions represented in genebanks.

Plant breeders tap the genetic diversity of CWR to develop crops that can handle higher temperatures, increased soil salinity and more severe disease outbreaks.  For example, genes from a wild rice species were used to make domestic rice varieties resistant to a virus that cost Asian farmers hundreds of millions of dollars in crop losses in the 1970s.  A wild tomato species provided genes that boosted the global tomato industry by $250 million per year.

Missing from collections are wild relatives of banana, cassava, sweet potato, pineapple, spinach and more.  The research, published in the journal Nature Plants, shows that more than 70 percent of essential CWR species are in urgent need to collection and conservation.  Some species identified as high priorities are in war-torn regions, or areas threatened by deforestation.

According to report co-author Colin Khoury, a scientist at the International Center for Tropical Agriculture, "The world's food supply is in a precarious position of depending on too few crop plant species."  The project's findings, he added, give scientists the first comprehensive global overview of which plants are missing and where collectors need to search for them.