Dry matter and nutrient accumulation in maize cultivated during the winter-spring season

Abstract

The aim of this work was to verify the dry matter accumulation, the total N, P, K, Ca, Mg and Zn extraction and the nutrient grain conversion by three maize genotypes (BR 201, BR 106, AG 519) grown during autumn and spring, in a red yellow latosol from Prudente de Morais, Minas Gerais. The treatments were arranged in a randomized complete block design with three replications. The maize plants were harvested in five development stages. The plants were separated into leaves, stalks plus leaf sheath, husks, cobs, and grains. The nutrient exportation by grains and total dry matter yields varied with the genotype. The nitrogen was exported by grain in a range which varies from 66 to 72%, the phosphorus, from 80 to 88%; magnesium, from 44 to 59%; calcium, from 3 to 5% and zinc from 48 to 59%. The nitrogen efficiency is maize genotype dependent as well. The BR 201 showed higher N conversion to grain production and higher percentage of grain exportation. There were no statistical differences for grain production per unity of phosphorus absorbed among the genotypes; however, the BR 201 showed the highest phosphorus exportation. The BR 201 also showed the highest grain production per unity of calcium absorbed in spite of having shown the lowest assimilation. The Ca/Mg ratio was magnesium extraction dependent.