Scientists say a poisonous pea could become a vital climate crisis crop, reports Robin McKie, of The Observer.
It is grown in some of the world’s most inhospitable, arid regions and is noted for being rich in protein. But the grass pea — although hardy and nutritious — comes with a catch. It contains a poison that can occasionally trigger irreversible paralysis, particularly among individuals who are already undernourished.
As a result, it is often grown only as an insurance crop, to provide short-term food supply when harvests of other crops have failed. Nevertheless, poisoning from Lathyrus sativus still occurs in Bangladesh, India, Pakistan, Nepal, Ethiopia and Algeria.
But now a group of UK scientists studying the grass pea have revealed the secrets of its poison production. Soon they expect to create versions that are free of its toxic side effects.
"Very soon, we will be able to make safe versions of the grass pea and provide our undernourished, overheated planet with a very valuable crop," project scientist Dr Anne Edwards, of the John Innes Centre in Norfolk, said.
The key biochemical steps by which the grass pea’s poison is made were revealed when scientists decoded the highly complex genome of Lathyrus sativus. They discovered details of the pathways that lead to the pea poison’s manufacture, leaving them poised to use gene-editing or standard breeding techniques to create versions that are poison-free or extremely low in toxins.
"Obviously you don’t want to create a version of the grass pea that does not make toxins and then find out that it is also no longer drought-resistant," Edwards said.
"However ... it seems there is no penalty from removing the toxin or having very, very low levels of it."
When eaten as part of a balanced diet, the grass pea is safe. But when other crops have failed and only the hardy grass pea survives, its consumption can have grim effects in the form of the neurotoxic disease of lathyrism.
However, once stripped of its toxic effects, the grass pea could have a crucial role in a world afflicted by the consequences of the climate emergency.
"We should not underestimate the potential of grass pea across the world," Edwards said.
"It’s a legume, and bacteria in its roots make fertiliser by converting nitrogen in the air into ammonium compounds, which it releases into the soil and improves it.
"It also has an enormous root system that goes deep into the ground. So growing the grass pea could play a major role in improving soil fertility across the planet."
Dr Peter Emmrich, one of the scientists working to develop safe varieties of the grass pea, said preparing for increased climate change meant crops would be needed that could cope with drought, flooding or inundations of salt water.
"Grass peas can survive such conditions." — Guardian News and Media
