Avaliação do estado nutricional da videira “Itália”, em três estádios de desenvolvimento, na Região de Jales-SP, utilizando o Método DRIS

Abstract

It was evaluated the nutritional condition of grapevine cv. Itália in the region centered at Jales, SP, using the Diagnosis and Recommendation Integrated System (DRIS). In 1991, 20 bearing vineyards in that region, using similar cultural practices, were surveyed nutritionally. The survey consisted in: (a) colecting soil samples at 0-20cm and 20-40cm; (b) colecting leaf samples (blade and petiole) at three different developing phases (at bloom, between pea and half-berry, and at verruson); and (c) evaluating grape yield. Using DRIS for thís evaluation showed that the system is adequate for grapevine culture, permítting the obtention of information on the sampling tissue, nutritional disorders and reference indexes for the nutritional balance. Leaf blade showed to be better sampling tissue than petiole, with much more consistent nutritional balance indexes. The method confumed that both blooming and verruson are adequate stages for sampling grapevine leaves. Data obtained in those two dates were much more consistent than those obtained when the berries were between sizes of pea and half-berry. Finally, DRIS allowed to determine that the stlldied vineyards presented, in general, macronutrients deficiencies, mainly of potassium, magnesium and sulfur. Dealing with micronutrients, on the contray, the problem was of excess, mainly of cupper.