The goal of optimizing grapevine nutrition is to improve vineyard productivity, sustainability, product quality, and vineyard profitability. The market demands for grapes drive grower decision-making in the vineyard. Raisin and juice grape growers aim to maximize yields, table grape producers need to maximize yield and fruit appearance, and wine grape growers prioritize berry quality parameters that influence wine composition often at the expense of yield. The environment affects vine growth and thus nutrient demand, so nutrient standards are not universal across vineyards in different regions or different grape markets.
The Plant Nutrition Team’s goal is to determine standards for grapevine nutrition levels appropriate for different varieties, markets, production goals, and environments. Understanding how different plant tissues respond to nutrient inputs and correspond to specific production goals will help develop these standards. The team includes researchers from Washington, Oregon, California, and Virginia.
To develop nutrient standards, the team is conducting vineyard trials in all four states represented by the research team. These trials evaluate vine responses to specific nutrients of regional concern to growers. Field-based research trials are being conducted to evaluate responses to variable nutrient levels through different rates of fertilizer inputs. This team works with the Sensor Development Team to test the ability of sensors to determine actual tissue nutrient levels. The team also works with the Product Quality Team to determine the influence of different nutrient levels on fruit and wine composition.
Below are the trials being conducted in each state.
- Washington: Field trials are being conducted in commercial Syrah, Chardonnay, Sauvignon blanc, and Concord vineyards to evaluate different nitrogen and potassium fertilizer rates. The team tests different tissue sampling strategies, and the Sensor Development Team takes images of vines in the different treatments to test how their sensor output correlates with tissue nutrient levels. At harvest time some of the experimental plots are processed into wine tested for chemical composition and in a sensory evaluation by the Product Quality Team.
- Oregon: Nutrition experiments are being conducted in three commercial vineyards, focusing on nitrogen in Chardonnay and potassium or magnesium in Pinot noir. Fruit from the nitrogen trial is provided to the Product Quality Team to produce wine, and analyze wine composition and sensory properties. Sensor ground-truthing will begin in 2022.
- California: Nutrient trials are being conducted in field grown vines and potted vines for raisin and table grapes. Nutrient treatments consist of nitrogen and magnesium application rates. Multispectral imaging is being evaluated within multiple vineyards.
- Virginia: Field trials are being conducted using both soil and foliar nitrogen application in Chardonnay and Chardonnel vineyards. The berries were sampled at harvest for yeast assimilable nitrogen (YAN) and basic fruit chemistry. Wines are being produced by the Product Quality Team, with focus on YAN.
Team members
Researchers (see details here)
- Markus Keller, Washington State University
- Paul Schreiner, USDA-ARS Horticultural Crops Research Unit, Oregon
- Matthew Fidelibus, University of California-Davis
- Dana Acimovic, Virginia Tech
Research Lab Staff
Pierre Davadant, PhD student, Washington State University
Pierre is studying grapevine physiology under the supervision of Dr. Markus Keller. He has a background in agriculture, viticulture, enology and teaching. Pierre is focusing on nitrogen fertilization and studies the impact of foliar-applied and soil-applied nitrogen on grape composition
Santosh Kalauni, PhD student, Oregon State University
Santosh is working in Dr. Paul Schreiner’s lab at the USDA-ARS Horticultural Crops Research Unit in Corvallis, OR. He is engaged in experiments to determine the effect of nutrient applications (N, K and Mg) on vine nutrient status, productivity, and fruit quality. He is examining nutrient sufficiency thresholds for various tissues and times from these experiments based on vine productivity and quality parameters.
Nataliya Shcherbatyuk, Postdoctoral Researcher, Washington State University.
Dr. Nataliya Shcherbatyuk is a postdoctoral researcher in Dr. Markus Keller’s lab. Her focus is on optimizing sampling protocols for efficient vineyard nutrient management. She is working on re-evaluating existing sampling protocols for grapevine tissue nutrient analysis; determining how rapidly vines respond to nutrient adjustment. Additionally, Nataliya has particular interest in nutrient recycling, specifically potassium. The main goal of her work is to improve tissue sampling protocols and enhance management practices for spatially heterogeneous vineyards.
