Reference values for vineyard nutrients in the Campanha Region estimated by the Mathematical Chance method

Viticulture in Rio Grande do Sul (RS), the southernmost state of Brazil, has been changing due to its expansion to new areas in the Campanha Region. Located in the south of the state, these areas have different edaphoclimatic conditions from those existing in the Serra Gaúcha, traditional production region. Thus, the estimation of reference values for leaf nutrient contents specific for the conditions of the Campanha is essential for the correct management of vineyards. Methods such as Mathematical Chance (MCh) enable the determination of sufficiency levels of leaf nutrients by evaluating commercial production areas. This work aimed to estimate reference values for nutrients in leaf tissue of grapevines in the region of Campanha by using the MCh method. Nutritional sufficiency ranges differed from those estimated by the official research for the state. However, they revealed high similarity with the results obtained by other studies carried out in the Campanha Region by using DRIS and CND approaches. Our results demonstrated that the MCh was able to estimate the infra- and supra-optimal limits, as well as the optimal levels for nutrients, indicating that there is potential for foliar diagnosis of vineyards in RS to be performed based on regionalized parameters.