Influence of nitrogen fertilization and green manure on the economic feasibility of no-tilled wheat in the Cerrado

• Main Authors: Douglas de Castilho Gitti, Orivaldo Arf, Mariana Melero, Ricardo Antonio Ferreira Rodrigues, Maria Aparecida Anselmo Tarsitano
• Format: Article
• Language: English
• Published: Universidade Federal De Viçosa 2012-04-01
• Series: Revista Ceres
• Subjects: Triticum aestivum L.; custo de produção; Crotalaria juncea L.; guandu; milheto; efeito residual
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-737X2012000200014&lng=en&tlng=en

The search for higher profitability in wheat crop with cost reduction technologies that may promote sustainability is an important matter in Brazilian agriculture. This study evaluated the profitability of no-tilled wheat, reducing nitrogen topdressing doses with the cultivation of green manure before the wheat crop. The experiment was carried out in Selvíria (MS), Brazil, in 2009/10. The experiment was arranged in a randomized block design with 36 treatments in splitplots and four replicates. The plots were formed by six types of green manure: Cajanus cajan L. BRS Mandarin, Crotalaria juncea L., Pennisetum americanum L. BRS 1501, fallow area and mixed cropping of Pennisetum americanum L. + Cajanus cajan L. and Pennisetum americanum L. + crotalaria which provided straw for no-tilled wheat in the winter, following the rice crop in the summer. The subplots were formed by six levels of topdressing nitrogen (0, 25, 50, 75, 100 and 125 kg N ha-1) using urea as a nitrogen source. The wheat grown after green manure in the previous winter crop, with no nitrogen topdressing and a rate of 25 kg ha-1 N, had more frequently production costs above the gross income. Wheat production cost after the mixed cropping Pennisetum americanum L. + Cajanus cajan L. and Pennisetum americanum L. + Crotalaria juncea L. from the previous winter crop, combined with nitrogen rates of 50 and 75 kg N ha-1, provided better profitability compared with the other green manures evaluated.