University of Idaho researchers have identified a naturally occurring genetic mutation in wheat that is associated with a 5% to 10% increase in yield, offering plant breeders a new tool to improve wheat performance while reducing breeding costs.
Scientists in the University of Idaho College of Agricultural and Life Sciences, led by wheat breeder Jianli Chen at the Aberdeen Research and Extension Center, screened germplasm collections, including spring wheat varieties developed by Pacific Northwest breeding programs, for the mutation. They confirmed its presence in several high-yielding wheat lines, including UI Gold, a hard white spring wheat variety released in 2022, along with several experimental breeding lines.
The mutation is a nucleotide deletion, in which a small section of DNA is missing. Researchers determined the deletion is associated with later flowering and an increase in spikelets, the flower clusters that develop into grain on a wheat head. Both traits can contribute to improved grain yields. Chen's team also identified the chromosome location associated with the beneficial mutation and developed molecular markers that can be used to screen breeding material.
The research was supported through a five-year, $15 million grant from the U.S. Department of Agriculture's National Institute of Food and Agriculture. Led by the University of California, Davis, the project included researchers from 22 institutions nationwide. Chen's program received $537,644 in funding and expanded on work completed through two previous USDA-NIFA collaborative grants.
In addition to identifying the mutation, the research team validated a more efficient genomic selection method for predicting wheat yield and related traits. Genomic selection uses DNA markers across a plant's genome to identify breeding lines with desirable characteristics before extensive field testing.
Traditionally, genomic selection for yield has relied on a platform containing 90,000 single nucleotide polymorphisms, or SNPs, which are variations at individual positions within a DNA sequence. Chen's team found that a platform using only 4,000 SNPs provided predictions that were as effective as the larger platform for yield and related traits.
The streamlined approach has reduced testing costs by about $60 per sample in Chen's breeding program. Researchers plan to evaluate the 4,000 SNP platform for additional characteristics, including drought tolerance and baking quality.
Source: University of Idaho, "U of I wheat breeder discovers genetic mutation associated with yield gain"