Himalayan grain demonstrates the potential of pangenome-guided breeding for higher yields and adaptability

Scientists from the Centre for Crop and Food Innovation at Murdoch University have shown how pangenome-guided breeding can be used to combine traits that often conflict with each other: stress tolerance and yield. This breakthrough was detailed in a study published in the prestigious journal Cell. The international team, comprising 22 institutions across 10 countries, demonstrated that by building a pangenome - a comprehensive map of an organism's genetic material that includes all possible genetic variations - breeders can locate and reintroduce beneficial genes and structural DNA variants that were lost during the initial domestication of crops.

The researchers used Tartary buckwheat, a hardy grain native to the Himalayas, as their proof of concept. Tartary buckwheat's wild relatives can withstand extreme conditions like intense UV-B radiation and cold temperatures, while cultivated varieties struggle with these factors. The study revealed a specific gene (FtRNH) that enhances stress tolerance in wild plants but is absent in cultivated versions. Additionally, a genetic region called FtPLATZ was found to be associated with larger seed size.

By integrating these wild alleles into cultivated Tartary buckwheat, the team produced a stacked candidate line that exhibited improved high-altitude adaptability, larger seeds, and higher yields. This method, which leverages the full genetic diversity of both wild relatives and local landraces, is expected to be applicable to a wide range of crops.

The study's lead author, Professor Rajeev Varshney, emphasized that traditional breeding methods, which compare a crop's genome against a single reference genome, often overlook the valuable genetic material lost during domestication. This new approach, he said, captures the complete vocabulary of an organism's genetic potential, including the genes that enable resilience.