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The perennial rice 'Yunda 107' is harvested in the Yunnan Province of China. Perennial rice can be harvested for successive regrowth seasons, maintaining a relatively stable yield and greatly reducing labor input. China News Service/China News Service via Getty Ima hide caption

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China News Service/China News Service via Getty Ima

Rice is arguably the world's most important staple crop. About half of the global population depends on it for sustenance.

But, like other staples such as wheat and corn, rice is cultivated annually. That means replanting the fields year after year, at huge cost to both the farmers and the land. For years, scientists have been tinkering with rice strains to create a perennial variety – one that would regrow after harvest without the need to be resown.

For what may be the first time in about ten thousand years of human rice cultivation, the new strains stay productive harvest after harvest.

Over two decades ago, researchers crossed a common Thai rice cultivar with a wild rice from Africa that was especially tenacious. They then spent years breeding for the desired traits until they landed on three new perennial varieties to test in the real world. Since then, some 45,000 farmers, mostly smallholding subsistence farmers, have tried growing the perennial rice.

"Now it's gotten on to where it's four years in a row," says Tim Crews, Chief Scientist and Director of the International Program within the Land Institute in Kansas.

Tim and his collaborator, Erik Sacks, a professor at the University of Illinois Urbana-Champaign, joined Short Wave Scientist in Residence Regina G. Barber for a live conversation at the Sci-Mic stage, during the 2023 Annual Meeting of the American Association for the Advancement of Science (AAAS).

During that conversation, they explained that with the development of perennial grains could come huge environmental benefits – from healthier soil to a lower carbon footprint – and be a boon for the people who grow them.

Curious about extra thumbs, battery breakthroughs and sustainability in space? Check your feed for more live Short Wave episodes from the AAAS Sci-Mic stage in coming weeks!

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Want us to cover another scientific innovation? As always, you can reach the show by emailing [email protected].

This episode was produced by Berly McCoy, edited by Gabriel Spitzer and fact-checked by Anil Oza. The audio engineer was Gilly Moon.