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landinstitute.org/our-work/peren...perennial-rice/

In the subtropical Yunnan Province of China, high-yielding perennial rice has been successfully developed. In 2021, perennial rice was grown on 15,333 ha by 44,752 smallholder farmers in southern China and is now expanding throughout SE Asia and Africa.

PR23 and a number of other selections were developed through a wide hybrid cross between annual, cultivated rice, Oryza sativa, and a perennial cousin of rice from Africa, Oryza longistaminata.  This wide hybridization approach is the same one being employed by breeders at The Land Institute to perennialize sorghum and wheat.