California Ag Network

Tag: ARS

  • New Tool to Combat Fusarium Head Blight in Wheat

    Agricultural Research Service (ARS) scientists and their colleagues have discovered a gene that can be used to develop varieties of wheat that will be more resistant to Fusarium Head Blight (FHB), a disease that is a major threat both overseas and to the nation’s $10 billion annual wheat crop.

    A paper reporting the discovery and the cloning of the gene, known as Fhb7, was published today in the journal Science.  The study was led by scientists at the Shandong Agricultural University in Shandong, China and co-authors include ARS researchers Guihua Bai and Lanfei Zhao in Manhattan, Kansas, and Steven Xu in Fargo, North Dakota.

    The discovery is a major advance in addressing a significant threat to the world’s wheat supply. FHB, also known as “scab,” is caused by a fungal pathogen, Fusarium graminearum, and results in significant losses in the United States, China, Canada, Europe, and many other countries. It also attacks barley and oats. When the pathogen grows unchecked in infected grains, it releases mycotoxins that can induce vomiting in humans, as well as weight loss in livestock when they refuse to eat the grains. The prevalence and severity of FHB outbreaks also could potentially be exacerbated by climate change and varying weather conditions, and by an increasing trend toward more corn production and no-till farming, which both may be increasing the prevalence of the pathogen in fields. Growers often must use fungicides to reduce FHB damage.

    The researchers found that the gene effectively reduces FHB by detoxifying the mycotoxins secreted by the pathogen. The gene also confers resistance to crown rot, a wheat disease caused by a related pathogen.

    The researchers originally identified the gene in Thinopyrum wheatgrass, a wild relative of wheat that has been previously used to develop varieties of wheat with beneficial traits, such as rust resistance and drought tolerance. They cloned the gene and introduced it into seven wheat cultivars with different genetic profiles to study its effects on plants grown under field conditions. The results showed that the gene not only conferred resistance to scab in the new plants, but it also had no negative effects on yield or other significant traits.

    The study sheds new light on the molecular mechanisms that can make wheat, as well as barley and oats, resistant to the pathogen that causes FHB.  New varieties of wheat with better FHB resistance using Fhb7 are expected to be available in a few years, the researchers say.

    This research supports the climate adaptation components of the USDA’s Science Blueprint. The paper can be found here.

    The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in agricultural research results in $20 of economic impact.

  • Bringing Space Technology to Water Needs in California Vineyards

    Beltsville, Maryland, (December 18, 2017) – ARS scientists are saving water in California’s vineyards by using satellite data and computer models to better manage water resources.

    Bill Kustas and Martha Anderson are fine-tuning computer models at the ARS Hydrology and Remote Sensing Laboratory in Beltsville, Maryland, to help vineyard managers determine how much water to apply and when to apply it. The models tap into satellite data that measure land surface temperature providing information about soil and vine moisture levels and rates of water use or “evapotranspiration.”

    ARS hydrologist Bill Kustas measures grapevine canopy width at a California vineyard to help evaluate satellite data used in models of vine water use.

    Winemakers want grapes of uniform quality, and that can be a challenge with vineyards that have different soils and climatic conditions across thousands of acres. Even a single vineyard can have a variety of irrigation needs, according to Kustas, an ARS hydrologist.

    The ARS model uses satellite measurements of land surface temperature in a unique way by separating out the vine canopy from the soil surface temperatures. This gives the model greater precision and enables researchers to better evaluate vine stress, says Kustas.

    Known as precision agriculture, the approach is helping the E. & J. Gallo Winery cut water use by allowing the grower to identify specific vineyard areas that are under stress and need irrigation. Gallo owns and operates 25,000 acres of vineyards in California and contracts with grape producers operating another 200,000 acres. The results also will be shared with other vineyard operators, offering the potential to save water across more than a million acres of vineyards in California.

    With water supplies critical in California, the state’s nut and fruit orchard operators are also likely to benefit from these efforts, Kustas says.

    Over the next two years, the ARS researchers plan to develop a daily digital map of evapotranspiration in California’s Central Valley, which includes some of the world’s most productive agricultural lands, at a resolution that will give growers a firm grasp of conditions in specific areas within their fields.

    You can read more about this research in the December 2017 issue of AgResearch magazine.

    For more information contact Dennis O’Brien, ARS Office of Communications.