Efficiency of fertilization with coated urea in the cultivation of cactus pear under rainfed conditions in Brazilian savannah

Abstract

Cactus pear is an important species for animal feeding in the regions of dry climate. There is no information on the fertilization with coated urea in the cultivation of cactus pear under rainfed conditions in the savannah region. The aim of the current study was to evaluate the forage potential of Nopalea cochenillifera variety Doce in yellow latosol under rainfed conditions in the Brazilian savannah, comparing the fertilization with urea and coated urea in different levels. A randomized block design was adopted, in a 2 × 4 × 2 factorial scheme, with the factors corresponding to two sources of nitrogen (urea and urea coated with polymers, N+), four levels of nitrogen (0, 60, 120 and 240 kg/ha/year) and two harvests (year I and year II). The plants were evaluated after 1 year of growth, in each year of evaluation, regarding the characteristics of growth, production, chemical and mineral composition and nutritional value. The level of 240 kg/ha provided higher emission of cladodes per plant (17.33 and 18.17), respectively, for N+ and urea. The highest nitrogen use efficiency was found in the level of 60 kg N/ha (142 kg/ha/year). NFC values were 3.5 g/kg dry matter (DM) higher when the cactus pear was fertilized with urea in year I and 5.4 g/kg DM in year II. The use of conventional urea promoted better results of agronomic and nutritional characteristics of the cactus pear, under rainfed regime, when compared to the use of urea coated with polymers.