Response of carrots dry matter yield and nutrients removal to nitrogen splitting and rates

Abstract

The appropriate handling of nitrogen fertilization aims to reduce losses and facilitate an efficient use of nutrients by plants. The objective of this research was to evaluate nitrogen split dressings and doses on yield dry matter and macronutrients removal by carrot. The experiment was carried out using a completely randomized design with a factorial (4x2) consisting of four doses of nitrogen (60, 90, 120 and 150 kg ha^-1) and two split dressings (1/3+1/3+1/3 and 1/6+2/6+3/6 of the total dose). The dry matter yield and macronutrients removal by the shoot, root and whole plant were evaluated. The highest dry matter yield of the root was obtained in the fractionation 1/6 + 2/6 + 3/6 in the dose 140 kg of N ha^-1. The maximum root removal of N, P, K, and Ca was obtained also in the fractionation 1/6 + 2/6 + 3/6, with a dose of 140 kg of N ha^-1, while the maximum removal of Mg and S was obtained with doses between 120 and 134 kg of N ha^-1, respectively. Macronutrients removed by culture, in decreasing order, were: potassium>nitrogen>calcium>phosphorus>magnesium>sulfur.