Iron uptake in vineyard soils and relationships with other elements (Zn, Mn and Ca). The case of Castilla-La Mancha, Central Spain

Abstract

In Castilla-La Mancha region (Spain) there are more than 500,000 ha of vineyards. The soils in the area of maximum culture intensity of wine grapes have a medium to high content in calcium carbonate. In these areas, the appearance of chlorosis symptoms is usually related to iron deficiency, but this is not the only element that is involved in these nutritional problems.Data from 110 soil profiles selected from Castilla-La Mancha region were taken following the procedure described in FAO-ISRIS-ISS. X-ray fluorescence was used to measure both soil and leaf concentrations of mineral elements. From the data obtained, the mean contents of topsoils (A and B horizons) in Ca, Fe, Mn and Zn were studied and compared with leaf contents in these elements. The data were geo-referenciated and displayed in spatial distribution maps.Concentration in soil of the considered elements were: 108.0 ± 28.8 g kg−1 for Ca; 22.1 ± 1.4 g kg−1 for Fe; 380.0 ± 740.0 mg kg−1 for Mn and 32.6 ± 14.0 mg kg−1 for Zn. Leaf concentration measured for the same elements were: 24.4 ± 49.4 g kg−1 for Ca; 440.0 ± 742.0 mg kg−1 for Fe; 130.0 ± 136.0 mg kg−1 for Mn and 20.3 ± 12.9 mg kg−1 for Zn. As average, Zn levels are more critical than Fe levels in soil and leaves for plant nutrition.Critical concentrations in micronutrients should be considered in order to explain and prevent symptoms of deficiency that could decrease the quantity and quality of wine grapes.