Documenting Symptoms and Critical Values for Nutrient Deficiencies in Wine Grapes

Plant nutrient deficiency symptoms provide useful information for farmers regarding crop health. Whenever possible, it is preferred to use chemical analysis of plant tissue to avoid severe nutrient deficiencies that occur when symptoms become visible. The goal of this project is to document nutrient deficiencies of red and white wine grapes to educate farmers regarding the value of proper fertilization. Between 2008 and 2011, 150 ‘Cabernet Sauvignon’ and 150 ‘Semillion’ wine grape plants (red and white, respectively) were grown in pots of sand. For each cultivar, 30 plants were grown with a complete nutrient solution and then 10 plants each were grown without a single nutrient, withholding either N, P, K, Ca, Mg, S, Fe, B, Cl, Cu, Zn, or Mn. During the 2010 and 2011 growing seasons, each week each plant was photographed using a black background, at the same time of day, and under shaded conditions. This resulted in a collection of over 6,000 photos.

Each of these photographs has been color adjusted to the black background using Adobe Lightroom. Photo albums are now being developed to show seasonal changes in the plants. A set of photographs for complete nutrient (control) supplied ‘Cabernet Sauvignon’ and ‘Semillion’ shows the growth of ‘healthy’ plants over a growing season. Sets of photos are also being developed for each cultivar to compare the healthy control plant to each nutrient deficiency throughout a growing season, thus showing changes in growth patterns and any foliage discoloration that developed. To date the ‘Semillion’ set is complete and the ‘Cabernet Sauvignon’ is being developed.

Upon completion, the images will be made available through ebooks, videos and individual photos.