Avaliação e seleção de genótipos de milho com e sem nitrogênio na fronteira oeste do Rio Grande do Sul

Abstract

Nitrogen (N) is the most required nutrient in corn crop, being nitrogen fertilizer as one of the factors that most affect the crop. The evaluation and selection of corn genotypes that are most efficient in the use of nitrogen is a possibility to reduce corn crop costs. The objective of this work was to evaluate the performance of maize genotypes submitted to treatments with and without nitrogen. The experiment was conducted at the Federal University of Pampa (UNIPAMPA) Campus Itaqui / RS, in 2016 and 2018. In the first year 16 genotypes were evaluated. In the second year the experimental design was in a 2 x 6 factorial scheme, in randomized blocks, with six maize genotypes and two nitrogen levels (with and without nitrogen). The following traits were evaluated: grain yield (RG) in the two years and for the second year: ear weight (PE), grain weight (PG), thousand grain weight (PMG), and number of grains spike (NGE). .Statistical analyzes were performed using the computer program GENES. In 2016, five families of half-siblings were selected. In 2018 for the variable RG H.S 2 and H.S 3 reduced their yields in the absence of nitrogen application in coverage. In general, H.S 1 presented higher grain yields with and without N application. For the other variables, except PMG, H.S 2 showed a reduction in values without nitrogen. H.S 1, H.S 2 and IMF 3 presented highlights for the variables PE, PG and NGE with and without N.H.S 1, in general, presented better behavior among the corn genotypes evaluated; and as an alternative among half-brother families to IMF 3.