Avaliação de metodologias na diagnose nutricional do melão cantaloupe irrigado na região da Chapada do Apodi RN

Abstract

The Nutritional status evaluation by leaf analysis is being a useful tool in nutritional diagnosis of several plants in several parts of the world. To interpret the leaves analyses are suggested several methodologies: Diagnosis and Recommendation Integrated System (DRIS), Balanced Indexes of Kenworthy (BIK), Critical Level by Reduced Normal Distribution (NCRIz), Critical Ranges (CR) and Mathematical Chance (MC). Those methodologies have been used to interpret vegetables chemical analyses at leaf, determining in the plant the ideal nutrient concentration. The objective of the present work was to evaluate methodologies in nutritional diagnosis of irrigated cantaloupe melon in Chapada do Apodi-RN. The work was developed in melon producing area between Rio Grande do Norte and Ceará states, Brazil, with predominance of "Cambissolo Háplico". The foliar Samples (analyzed as N, P, K, Ca, Mg, S, Fe, Mn, Cu, Zn, and B) and respective productivities were collected in 100 farming supplied by producers of melon from Chapada do Apodi - RN. In the interpretation of the results, the values classes of nutrients concentrations for most of the methodologies are concordant, except for mathematical chance methodology, in which differed in a large part of the reference patterns. The Fe, B and P are between the five more deficient nutrients and the Cu and the S in excessive concentrations in most of the methodologies. The methodologies DRIS, BIK, NCRIz and CR were comparable and equally efficient in the interpretation of the leaf diagnosis of irrigated cantaloupe melon in Chapada do Apodi - RN, Brazil, establishing reference patterns for the culture in hierarchical order of nutritional limitation with similar values the averages of adaptation of high productivity farming