California Ag Network

Tag: USDA Science Blueprint

  • Extending the Shelf-Life of Strawberries

    Advances in technology, automation, and remote sensing is a cross-cutting, macro movement in science impacting agriculture outlined in the USDA Science Blueprint (PDF, 2.6 MB). The Science Blueprint guides USDA’s science priorities for the next 5 years, building from past success. Relative to other crops, many specialty crops are more dependent on agricultural labor for production, harvesting, and processing. This is part of a blog series that highlights research investments to advance automation and mechanization for specialty crops.

    We’ve all enjoyed some delicious strawberries this summer, but a short-shelf life can limit that enjoyment. One of the biggest challenges in U.S. strawberry production is managing diseases and pests. The fungal pathogen Botrytis cinerea results in gray mold, or the unappetizing gray fuzz that can quickly appear on strawberries all too soon after we get them home. Growers typically apply fungicides on a weekly basis to control gray mold as well as other fungal diseases.

    Agricultural Research Service (ARS) researchers developed an alternative technology called PhylloLux, which combines Ultraviolet-C (UV-C) irradiation followed by a specific dark period. UV-C kills microbes by damaging their DNA, but doses required to kill fungal pathogens can also damage plant leaves and fruit. ARS researchers found that including a dark period after irradiation prevents activation of a daylight-induced mechanism that repairs DNA damage in microbes and allows for much shorter UV-C irradiation times. The resulting UV-C/dark (UV-C/d) treatment of strawberry plants twice per week, as suggested for commercial application, did not affect nutritional values of strawberry fruit.

    To move the technology to commercial use, ARS scientists first developed a self-propelled, fully automated and programable apparatus that was used for night-time irradiation of strawberries in a high tunnel culture. In 2019, a second robot was developed for autonomous application of UV-C/d in commercial strawberry fields. Preliminary results from two farms in Delaware indicate the UV-C/d application was as good as weekly fungicide sprays.

    The combination of innovation in approach to disease management and in application through new technology is a result of close collaboration between plant pathologists, horticulturists, entomologists and engineers. In fall 2020 larger California pilot tests are planned for targeted pests, including aphids, thrips, scale insects, and slugs.

    PhylloLux is a prime example of innovation in agriculture production as a solution for farmers, consumers, and the environment in support of the USDA Agriculture Innovation Agenda goal to increase U.S. agricultural production by 40 percent while cutting the environmental footprint of U.S. agriculture in half by 2050. Growers can benefit from the resulting drastic kill of fungal plant pathogens causing gray mold, powdery mildew, and anthracnose. The new method is also an effective control for spider mites, further reducing produce loss to growers. Reducing pesticide use improves environmental outcomes and has potential for organic as well as conventional production. And we’ll all benefit from enjoying those strawberries longer.

    This research supports the “value-added innovation” theme outlined in the USDA Science Blueprintand moves us closer to meeting the goals outlined in USDA’s Agriculture Innovation Agenda. – By Dr. Fumiomi Takeda, Research Horticulturist, Dr. Wojciech Janisiewicz, Research Plant Pathologist (retired), Dr. Joseph E. Munyaneza, National Program Leader, Vegetable, Sugarbeet & Greenhouse Crops, USDA Agricultural Research Service

  • 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.