The genes responsible for the wide range of freezing temperatures that can be tolerated by different wheat varieties have been identified by a team of U.S. and European scientists, led by a plant scientist at the University of California, Davis.

The study results suggest that the genes that regulate frost-tolerance are activated at milder temperatures (53-59 degrees F) in frost-tolerant wheat varieties than in frost-susceptible varieties.

The findings, reported in the March issue of the journal Plant Molecular Biology, are important for better understanding winter injury, a major economic risk factor in producing wheat.

"It has been difficult for wheat breeders to develop more winter-hardy varieties because frost tolerance in wheat is a complex trait that is regulated by many genes," said Professor Jorge Dubcovsky, a wheat breeder and geneticist.

"The identification of these genes will enable breeders to develop hardier, more productive wheat varieties, which is of vital importance in light of growing pressures to increase global food production," he said.

As the world's leading exporter of wheat, the United States annually produces more than 50 million metric tons of wheat, which is used to make a broad spectrum of food products ranging from breads to pastas.

This study was funded by the U.S. Department of Agriculture -- Cooperative State Research, Education and Extension Service, the Hungarian Wheat Spike Consortia, the Hungarian National Research Fund, the National Science Foundation Plant Genome Program and the Ohio Plant Biotechnology Consortium.

The study is part of an ongoing research program by Dubcovsky and colleagues to uncover the genetic basis of important wheat traits. More information on this research is available at: http://www.plantsciences.ucdavis.edu/Dubcovsky/.