Parcelamento de doses da adubação nitrogenada na produtividade e qualidade fisiológica de sementes de trigo

Abstract

The application of nitrogen (N) in the correct dose and at the right time can favor the productivity and quality of wheat seeds. In this sense, the aim was to evaluate the effect of splitting and doses of nitrogen fertilization on the productivity and physiological quality of seeds of wheat cultivars. The seeds were produced at the National Soybean Research Center, in Londrina-PR, in a randomized block experimental design in a 2 × 7 factorial scheme, with four replications. The factors were constituted by two cultivars (BRS Gralha-azul and BRS Sabiá) and seven combinations of doses and splitting of nitrogen fertilization (0 kg ha-1, 40 kg ha-1at tillering, 80 kg ha-1at tillering, 40 kg ha-1at sowing, 80 kg ha-1at sowing, 40 kg ha-1at sowing + 40 kg ha-1at tillering, 20 kg ha-1at sowing + 60 kg ha-1at tillering). The following were evaluated: productivity, germination, first germination count, length and dry mass of seedlings, emergence of seedlings in sand and emergence speed index. The data were subjected to analysis of variance with comparison of means by the F test, between genotypes, and Scott-Knott, between N combinations. The effect of nitrogen fertilization on seed productivity varies with the cultivar. The application of 80 kg ha-1N at sowing favors the vigorof the seeds for BRS Gralha-azul, and the application of 40 kg ha-1N at sowing, or 80 kg ha-1N at tillering favors the production of quality seeds for BRS Sabiá. The inadequate supply of N impairs the physiological quality of seeds produced.