Desenvolvimento inicial do feijão-caupi em função de crescentes doses de molibdênio

Abstract

The cultivation of cowpea began with the advance of colonization of the country, being introduced in the state of Bahia and spread by routes in the interior of the Northeast, becoming highly adapted to edaphoclimatic conditions and characterizing as the main source of protein of the sertanejo until nowadays. Even when it is a legume, the bean can not supply its nitrogen demand only with what is produced by biological fixation, and associated with this condition, the deficiency of molybdenum, an important element in nitrogen metabolism can be an important strategy of nitrogen. nutritional management that provide the expression of their maximum productive potential. The objective of this work was to evaluate the behavior of cowpea cv. Paulistinha, when subjected to increasing doses of molybdenum associated with nitrogen doses, seeking to determine the treatment that provided the best development for the studied variables. The experimental design was in blocks, in a 5x2x3 factorial arrangement, with the following treatments: 5 doses of molybdenum (0, 40, 80, 120 and 160 g / ha), and 2 doses of nitrogen (0, 80 kg / ha). , with 3 repetitions, totaling 30 experimental units. The source of molybdenum used was sodium molybdate, and nitrogen, urea. The treatments were applied 20 days after seedling emergence. The studied variables were: plant height (cm), stem diameter (mm), leaf area (cm²) and fresh matter mass (g). The data were submitted to variance analysis and later to polynomial regression analysis. Increasing doses of molybdenum applied via leaf provided higher plant height, stem diameter and leaf area in cowpea. The variable fresh matter mass was not influenced by the applied treatments.