Scientists have assembled a first of its form ‘pangenome’, a sort of reference genome, by stitching collectively key components of genomes from 144 varieties of wild and cultivated varieties of rice from Asia. Much just like the Human Genome Project in 2003 mapped genomes from a variety of people, expressing the genetic range of the human species, the rice pangenome permits researchers to develop new rice cultivars and introduce new traits for disease-tolerance in addition to resilience towards local weather shocks.
Rice is staple for practically two-thirds of the globe. It is the first crop grown in India over the monsoon months of June-September. In 2024-25, India produced a file 220 million tonnes of rice over 51,000 ha with a mean yield of 4.2 tonnes/ha. Several research through the years have warned that rising temperatures as a result of local weather change wouldn’t solely have an effect on yields but additionally improve arsenic uptake amongst a number of rice varieties. India’s common temperature has elevated by 0.7º C since 1901. 2024 was the most well liked yr on file, with the typical minimal temperature 0.9º C above the long-term common.
Earlier this month, the Indian Council of Agricultural Research (ICAR) introduced the event of two varieties of genome-edited rice, Samba Mahsuri and MTU 1010, that reportedly promise larger yields and higher drought resistance. These nonetheless are but to be launched into farmer fields.
To develop the pangenome, the scientists — practically all related to the Chinese Academy of Sciences — report enterprise a “deep analysis of complex gene flows” each inside cultivars (domesticated) and between cultivars and wild rice, highlighting the evolutionary and domestication pathways of numerous rice sorts. This examine strengthened assist for the speculation that each one Asian cultivated rice had an evolutionary origin from a wild selection known as Or-IIIa, the ancestor of japonica.
Asian cultivated rice (Oryza sativa L.) was domesticated from its wild progenitor O. rufipogon, and is one of crucial meals crops on this planet. Or-IIIa is a variant of O. rufipogon.
While reference genomes of a species usually confine themselves to figuring out the attribute genes that make up a species, a ‘pangenome’ has the widespread genes in addition to maps out the distinctive genes discovered within the particular person rice varieties. It presents a extra full understanding of the genetic variation current in rice.
Primarily utilizing ‘PacBio high-fidelity’(HiFi) sequencing expertise and computational strategies, their evaluation revealed 3.87 billion base pairs of novel genetic sequences absent from the only acknowledged reference genome, O sativa ssp japonica.
They recognized 69,531 genes collectively spanning the pangenome, with 28,907 core genes and 13,728 wild-rice-specific genes.
Population genetics research have earlier proven that historical japonica rice was first domesticated from the O. rufipogon group IIIa (Or-IIIa) inhabitants in China, and that indica rice was subsequently domesticated when historical japonica unfold southward and westward in Asia and crossed with the native O. rufipogon group I (Or-I) inhabitants.
Another key discovering of the examine was that of the 69,531 genes recognized, about 20% have been particular to wild rice. These genetic sources can enhance understanding of rice environmental adaptation, phenotypic plasticity and regeneration potential. “By bridging the gap between wild and cultivated rice genetics, our study opens new avenues and provides useful wild rice resources for developing superior and more productive rice varieties,” the authors notice.
“These improved varieties could incorporate valuable traits from wild rice species, potentially enhancing their resilience to rapid environmental changes.”
Published – May 09, 2025 07:30 am IST
