Sistema integrado de diagnose (DRIS) para a cultura do algodão no município de Silvânia-Goiás

• Autor(a) principal: SOUZA, Roberta de Freitas
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tde/2680
• topic: estado nutricional; normas; índices; faixas de suficiência; nutritional status; norms; indices; sufficiency ranges; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA

The Diagnosis and Recommendation Integrated System (DRIS) is an efficient tool for nutritional diagnosis on several crops. However, it no longer has been used on cotton crop, mainly in Goiás State. This work aimed to gain DRIS norms and diagnose the most limiting nutritional factors to obtain high cotton yields, using soil and leaf analysis, interpreted through critical levels or concentration ranges and DRIS techniques. Sampling sites were chosen on commercial area according to local topographic features and soil classes, trying to maintain their inside uniformity. Soil and leaf samples were taken at the full flowering stage (90 day after seeding). Ten leafs from each point were sampled, withdrawing the fifth leaf from the apex of the main stem, and for soil analysis six single samples from 0 to 20 cm at each point. Yields were assess after physiological maturation, taking two seeding rows five meters long for harvesting cotton fiber. Soil and leaf data were interpreted through DRIS and concentration ranges techniques. Norms were established from populations with yields greater than 4 Mg ha-1 of nutmeat cotton for calculating the DRIS indices. The diagnosis techniques assessed in this work showed distinct interpretations. The nutrients S, P, B, Zn, Fe and Mn showed to be the most limiting ones, as evaluated on by soil and analysis and diagnosed through the DRIS technique. Using the concentration range technique P, Zn and SOM in soil data, whereas in leaf data, S, Zn, K and B, are the most limiting ones. DRIS showed higher sensibility for diagnosing nutritional deficiencies, moreover, for micronutrients.