Cornell researchers will use genomics to help smallholder farmers in at-risk areas in Africa, Asia and Latin America, thanks to a $3 million grant from the Bill & Melinda Gates Foundation.
The researchers say one of the best long-term solutions to increasing productivity is to improve the crop varieties that smallholder farmers grow. They will use the state-of-the-art plant breeding method known as genomic selection to boost the rate of variety improvements in maize and wheat by two- to threefold. It will be the largest scale test to date of the efficacy of genomic selection.
"Farmers with small holdings of land in developing countries play key roles in poverty reduction and food security but are under tremendous pressure to keep pace with the rising demand for food," said Mark Sorrells, who chairs Cornell's plant breeding and genetics department and is helping to head up the project. "Traditional solutions to increasing productivity typically entail more effective irrigation and nutrient management, but both solutions are expenses that smallholder farmers can ill afford. Genomic selection is the next frontier for rapid genetic gains in maize and wheat."
"This project will ultimately help small farmers in developing countries increase their yields and improve their livelihoods. The project will also act as a blueprint for breeders of other crops to embrace the benefits of genomic selection," said Jean-Luc Jannink, quantitative geneticist with the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS) at the Holley Center for Agriculture and Health on the Cornell campus and an adjunct professor at Cornell.
Sorrells and Jannink will partner with the Mexican-based International Maize and Wheat Improvement Center (known by its Spanish acronym CIMMYT).
Genomic selection combines powerful statistical methods with new DNA marker and sequencing technologies to select untested germplasm lines based on predicted performance. Genomic selection reduces the expense and years involved in field testing, thereby greatly cutting the time needed to complete plant breeding cycles and bring new varieties to market. In addition, plant scientists can select for the ability of particular varieties to thrive under other agronomic stresses faced by smallholder farmers, like drought or nitrogen-depleted soil.
Jannink and Sorrells will use genomic selection to test varieties under development in CIMMYT's maize and wheat breeding programs to evaluate four efficiencies that may contribute to better yields. First, the genomic selection model increases the sample size of available data to examine so that complex, environment-dependent traits, such as drought resistance, can be predicted more accurately. Second, these more accurate predictions allow for an accelerated breeding cycle. Current wheat and maize breeding plans require at least four to six generations, while genomic selection can reduce that to a single generation. Third, a seed does not need to be evaluated in an environment to predict its performance in that environment. This is important because national breeding programs in developing countries do not always have the infrastructure required to evaluate potential varieties. Fourth, using genomic selection, plant breeders can help manage diversity so that the genetic gains obtained today do not come at the expense of traits needed in the future.
Sorrells and Jannink will rigorously test genomic selection efficiencies in the CIMMYT maize and wheat breeding programs. Smallholder farmers will benefit directly from the increased rate of improvement. If successful, the project will provide a model for other crops, leveraging research across the world plant breeding community.
John Bakum is a communications specialist in the College of Agriculture and Life Sciences.