Chinese scientists have made a groundbreaking discovery in the fight against a devastating wheat disease known as yellow rust.
The team has created the world’s first genetic map that tracks wheat’s resistance to yellow rust—a fungal disease that can significantly reduce both the yield and quality of wheat crops. This achievement promises stronger, more resistant wheat varieties and could lead to a decrease in pesticide usage.
Yellow rust, often called the “wheat cancer,” is caused by a rapidly mutating fungus. Every five years or so, a new dominant strain emerges, leading to about a 10% loss in global wheat yields annually. For regions that rely heavily on wheat as a staple food, especially in the Global South, this is a significant concern.
“This study systematically reveals the genomic characteristics of wheat’s interactions with the yellow rust pathogen over the past century,” said Professor Kang Zhensheng, a leading member of the research team from Northwest Agriculture and Forestry University. “It also uncovers how resistance genes and pathogen strains have co-evolved.”
The researchers analyzed genetic data from over 2,000 wheat samples worldwide and reviewed more than 47,000 records of how different wheat varieties responded to yellow rust in various environments. Through this extensive study, they identified 431 genetic locations associated with resistance to yellow rust, effectively creating a comprehensive map of resistance genes.
By diving deeper into these findings, the team successfully isolated three new resistance genes. One of these genes, named Yr5x, shows resistance to multiple strains of the yellow rust fungus, offering hope for developing wheat varieties with broader and longer-lasting resistance.
Another gene, Yr6\/Pm5, provides dual resistance to both yellow rust and powdery mildew, another damaging wheat disease. The discovery of this gene reveals a new mechanism by which crops can resist multiple diseases simultaneously.
The identification of these “elite” genes is a significant step forward. “This map is a valuable resource for deploying resistance genes in wheat breeding programs,” explained Professor Han Dejun, another member of the team. “By combining these resistance genes, we can significantly extend the effective lifespan of resistant wheat varieties.”
Current wheat varieties often lose their resistance within a few years due to the evolving nature of pathogens. However, the newly identified genes could maintain their effectiveness for over a decade, potentially transforming how wheat is cultivated worldwide.
Wheat breeding lines that incorporate these genes are now undergoing field trials in major wheat-growing regions both within the Chinese mainland and internationally. This advancement is not just a leap forward for science but also provides robust support for reducing pesticide use and strengthening global food security.
