Sugar Production in Wine Grapes
Wine grape production relies on sugar manufactured in the foliage being deposited in the fruit. The complex processes involved require key nutrients at key growth stages throughout the season and Phosyn´s program can supply these targetted inputs.
Healthy green foliage must be maintained throughout the growing season so that the vine is able to make maximum use of the available sunlight to produce sugars. Deficiencies of zinc, magnesium, iron and manganese are common and must be treated to avoid lost production. The Phosyn product range contains high performance products for effective control of leaf chlorosis.
Flowering and fruit set are critical to overall yield and quality. Early in the season the developing flower cluster attracts little, if any, of the sugars produced by the vine or supplies of the key nutrients boron, zinc, and phosphorus. Foliar application of Bortrac 150, Zintrac 700 and Hydrophos will ensure optimum levels in the flower cluster at this time.
Bunch closure, through veraison to harvest
As the berries develop and increase in size they must receive a balanced supply of magnesium, potassium, and calcium to avoid disorders such as bunch stem necrosis or problems of acidity. Foliar calcium sprays also reduce susceptibility to botrytis. Foliar sprays of Hydromag 500, Agripotash (wine grapes only) and Caltrac provide these essential nutrients during these critical stages.
Elevating sugar content - Trials Information
Replicated field trial carried out in California on the Chardonnay variety.
The Phosyn phosphorus, calcium and zinc program in this trial elevated sugar content.
Observations were made throughout the production process by winemaker to lab technician and all were positive.
"Definitely better quality", "Higher quality fruit" and "Sounder fruit" were all comments recorded when describing the treated fruit.
Author: James Craske, USA
Published: July 2002