23 June 2022
Key crops missing in global gene banks
Published online 19 May 2022
Gene bank stores of important agricultural crops are ‘moderately comprehensive’, but some vital plants are under-represented.
International gene bank collections cover nearly two-thirds of key domesticated agricultural crops, known as ‘landraces’. But some crops, such as potatoes and peas, are less well represented.
An international team, including scientists from the International Center for Agricultural Research in the Dry Areas (ICARDA) in Morocco and Lebanon, surveyed the genetic plant resources conserved in a network of agricultural research centres. Their goal was to assess how well these collections represent the geographic distribution and diversity of 71 distinct sub-groups of 25 essential cereals, legumes, tubers, roots and fruit crops.
They found that, on average, 63% of the geographic distribution of these vital crops was represented within gene bank collections. However, that average concealed a huge range, from 81.6% representation for breadfruit and 81.5% for bananas and plantains, to just 43% for yams and 50.3% for potatoes.
“I thought that the big crops, like cereals, would be the best collected and the stuff that we consider more neglected would be less well collected. That didn't turn out to be the case,” says Colin Khoury from San Diego Botanic Garden, in the United States, and the International Center for Tropical Agriculture in Colombia.
There was also considerable variation in gene bank representation within all the landrace crop groups, even those with greater coverage. For example, nearly 90% of barley crops with hulled grains were represented in gene bank collections, but only 31.3% of barley crops with naked or hull-less grains.
The study also identified geographic areas where landrace diversity had relatively low representation in global gene banks. For example, small regions in India and Morocco were home to uncollected landrace groups for up to nine crops.
“This means that there is a real danger that we could completely lose that material if it is not represented in a seed bank,” Henry says. This is especially a risk for crops grown in areas exposed to the impacts of natural disasters and climate change.
Ramirez-Villegas, J. et al. State of ex situ conservation of landrace groups of 25 major crops. Nature Plants https://doi.org/10.1038/s41477-022-01144-8 (2022).