A comparative study on nutritional aspects of the soil profile and plant nutrition in 5 Thompson Seedless grape (Vitis vinifera) vineyards of different vigor and productivity was carried out for 4 years in the Central Valley of Chile. Monthly analytic determinations of total N, P, K and N reserve fractions such as arginine, total amino acids, and reserve carbohydrates in canes, shoots and roots were measured. Soil profile fertility, physical soil properties, root system quality and nutritional levels on roots and aerial parts show satisfactory relations with vigor and/or productivity. Conventional petiole analysis at the full bloom stage was not very efficient to separate the vineyards, whereas N reserves, carbohydrate reserves and an eventual P reserve found in the roots during the dormant period appeared closely related to vineyard condition and productivity. Additionally, this study established seasonal variation curves for nutrients in the roots and aerial parts as well as the extraction of N, P, K, Ca and Mg in a variety of productivity-vigor situations. The relation between these cyclic changes of nutrients (including carbohydrates) and internal nutritional competition is discussed. |
ChileanJAR
