The Bleeding Edge: Bots and Rots

The USDA, top university researchers team up to breed new downy mildew resistant grapevines using robots and VitisGen AI to speed up the process.

Bryan Avila the Vintners Institute. The Vintners Institute brings wine industry producers and allies together, online and in-person, to innovate with nature, educate the workforce, and inspire good leaders. A freelance writer for Wine Business Monthly’s Trials section, Bryan covers advancements in viticulture and enology at the university level and the applied research trials that viticulturists and winemakers use to implement them.

Bryan Avila is a

Co-Project Director/Spokesperson: Dr. Lance Cadle-Davidson, United States Department of Agriculture-Agricultural Research Services (USDA-ARS), Geneva, New York. Dr. Lance Cadle-Davidson is a research plant pathologist with the USDA-Agricultural Research Service at the Grape Genetics Research Unit in Geneva, NY. For the past two decades, he has led a research program focused on fungal pathogens of grapevine and has co-led the VitisGen grape breeding project since its inception. His collaborative and multi-disciplinary research program translates new technologies for genetics and trait analysis for use in grape breeding and disease management.

AI/Machine Learning Expert: Yu Jiang, Ph.D., associate professor at Cornell University, Geneva, New York. Dr. Yu Jiang is an assistant professor of systems engineering and data analytics for specialty crops at the Horticulture Section, SIPS, Cornell AgriTech, Cornell University. His research aims to address grand challenges in agrifood systems by full-chain optimization through integrated solutions consisting of multimodal sensing, robotics, and data analytics. His recent focuses are in agricultural robots and AIbased data analytics for digital viticulture with an emphasis on grape disease.

Background

Downy and powdery mildew are some of the most pervasive plant diseases in the world. Unfortunately for grape growers, these filamentous fungi have an affinity for Vitis vinifera. These biotrophic water molds are parasitic organisms that live off plant cells. This means that their hyphae, in search of nutrients, destroy leaves and grape tissues leading to secondary infections of native yeast and bacteria which readily feed on the exposed juice, compounding rot conditions on the vine and finally resulting in increased microbial loads on harvested fruit. Once in the winery, even though these molds need oxygen to live, their secondary infections can lead to elevated volatile acidity numbers which may require additional sulfites, de-VA treatments or force changes in winemaking style. which can further compromise wine quality—in addition to any moldy flavors imparted by the mold itself. Prevention is key.

According to the UC Davis Integrated Pest Management program, regarding downy mildew, once the cordons or canes are wetted, infection occurs after 10 to 13 hours of leaf wetness when temperatures remain between 50°F and 80°F. If lesions are found about a week after the initial infection, then monitoring for disease development is recommended. Depending on the severity of the infection, the UC Davis Powdery Mildew Risk Index helps the grower determine the magnitude of the disease pressure as well as the frequency and type of fungicidal sprays needed to control the outbreak. When spraying fungicides, it is recommended to alternate usage between different types of fungicides that have different mechanisms of action to reduce the chance of fungicide resistance. In other words, it takes a lot of different fungicides to get things under control once powdery mildew takes hold.