Model of AhARF2-2 determining peanut seed size: AhIAA13 binds AhARF2-2 via the AUX/IAA domain. Auxin releases AhARF2-2, which recruits TPL to suppress AhGRF5. Credit: Nature Genetics (2025). DOI: 10.1038/s41588-025-02170-w

Researchers from Australia and China have identified crucial structural variations that determine seed size and weight in peanuts, paving the way for the development of higher-yielding crop varieties.

Comprised of researchers from Murdoch University, Henan Agricultural University, Shanghai Jiao Tong University and the Shandong Academy of Agricultural Sciences, the team of scientists have assembled a pangenome of that will serve as a fundamental resource for the genetic enhancement of legume crops.

The study, in Nature Genetics, assessed the genome-wide diversity of 269 peanut accessions, including , landraces and improved species. The researchers found significant genomic variations and highlighted trait-related variations that affect seed size and weight, two of the most critical traits that affect peanut yield.

The study traced back the evolution of domesticated peanut varieties from their wild relatives, discovering that the gene likely responsible for regulating —and therefore yield size—was absent in all 61 wild species analyzed.

In a groundbreaking first, the researchers also discovered that the gene Aharf2-2 negatively regulates seed size, and that the deletion of this gene makes seeds bigger.

Speaking on the findings, Prof Rajeev Varshney, Director of the Center for Crop and Food Innovation at Murdoch University and Corresponding Author of the study, said, "Despite the global importance of peanuts, our understanding of the and evolutionary factors that influence peanut pod size and weight has been very limited, until now.

"This study offers the most comprehensive genomic variation resource of peanuts to date and will be an invaluable tool for peanut breeding and crop breeding efforts going forward."

Murdoch University Pro-Vice Chancellor and Director of the Food Futures Institute, Professor Peter Davies, added, "This research is a remarkable achievement that offers extensive insights into the structural variations and molecular mechanisms that are responsible for seed size and weight. What makes this especially exciting is that it offers new information that can be applied to numerous crops of economic importance, such as cotton and rapeseed."

More information: Kunkun Zhao et al, Pangenome analysis reveals structural variation associated with seed size and weight traits in peanut, Nature Genetics (2025).

Journal information: Nature Genetics , Nature

Provided by Murdoch University