V. S. Marchioro

Wheat genotypes and mineral and biological sources of nitrogen in no-tillage.

Cultivars that use nitrogen (N) efficiently are important for reduction of production costs, achievement of satisfactory yield, and reduction of environmental pollution cause by nitrate leaching. In this study, we aimed to evaluate the interactions of wheat genotypes with important agronomic characteristics through the application of N sources: mineral (urea), biological (Azospirillum brasilense), and zinc oxide (a total of 8.50% of Zn) with ammoniacal nitrogen (a total of 7% of N) applied to the seed. The experiment was conducted under no-tillage system after succession with soybean (Glycine max). We used a completely randomized experimental design in a 3 × 6 factorial scheme with four replicates. The treatments were three wheat cultivars (CD 104, CD 150, and CD 116) and six sources of nitrogen with or without associations with Zn and Azospirillum. We observed differences between the genotypes studied regarding response to nitrogen for the following grain yield components: hectoliter weight (HW), mass of thousand seeds (MTS), and number of ears per meter (NEM). No significant effects were found in the genotypes with respect to N topdressing, Azospirillum, and Zn regarding grain yield (GY). The need for N to the grain yield of cultivars CD 104, CD 150, and CD 116 were met owing to total N in the soil, probably because of the levels of organic matter (OM) and no-tillage in soil with soybean crop residues under the edaphoclimatic conditions of the municipality of Palotina, Paraná state. Genótipos de trigo e fontes de nitrogênio mineral e biológica no plantio direto Wheat genotypes and mineral and biological sources of nitrogen in no-tillage Marlon Mathias Dacal Coan1 Volmir Sergio Marchioro2* Francisco de Assis Franco2 Adriel Evangelista2 Kátia Regina Geremias3 Valdemar Patel3 Joana Neres da Cruz Baldissera1 1Universidade Estadual de Maringá – UEM, Av. Colombo, 5790, Bloco J45, 1o Andar, Sala 101, 87020-900, Maringá, PR, Brasil 2Cooperativa Central de Pesquisa Agrícola – COODETEC, Pesquisa, Programa de Melhoramento Genético, BR 467, km 98, Canadá, 85813-450, Cascavel, PR, Brasil 3Pontifícia Universidade Católica do Paraná – PUCPR, Campus Toledo, Av. da União, 500, Jardim Coopagro, 85902-550, Toledo, PR, Brasil Autor Correspondente: *E-mail: volmir@coodetec.com.br PALAVRAS-CHAVE Triticum aestivum L. Azospirillum brasilense Sustentável Ureia