Visual Deficiency Symptom Differences Between Red and White Wine Grapes

Detecting and diagnosis deficiency symptoms on wine grapes is challenging since many environmental and disease stress factors can resemble nutrient deficiency stress.  To document  visual symptoms of plant nutrient deficiencies, 150 'Semillion' and 'Cabernet Sauvignon' grape plants were planted in sand culture in 2008.  Since that time, the plant a have been grown so that at least 5 plants of each cultivar have had N, P, K, Ca, S, Mg, Cu, Cl, Fe, B, Mn, or Zn with held, while at least 10 plants have had complete nutrient solution supplied to them.  Starting in 2010, during the growing season, photos were taken of each plant weekly. In 2010, 3 replicate plants of each treatment per variety were destructively harvested, divided into plant components, and analyzed for plant nutrient concentration.  This poster will display the visual similarities and differences in symptoms of the red versus the white grape plants.