Behavior of experimental green corn hybrids at different nitrogen topdressing rates

Abstract

The objective of this study was to evaluate the agronomic performance of 22 experimental hybrids of maize for the production of corn subjected to two doses of nitrogen fertilization (0 and 144 kg ha –1 , environments 1 and 2, respectively). The research was carried out at the experimental station of the University of Gurupi, State of Tocantins. The experimental design used randomized blocks with two replications. Variables were evaluated for agronomic and commercial interest for the production of corn and analyses of variance and Scott-Knott tests were performed for all variables. The number of commercial ears was regarded as the main variable studied and, therefore, it was used to construct the graph to verify the means of cultivars, simultaneously, in both environments. There was significant genotype × environment interaction only for the variable percentage of commercial ears. However, there were significant differences between hybrids considering the variables male and female flowering, gap between male and female flowering, amount and weight of ears with husk, and number of commercial ears. There were no significant differences between the two environments regarding all the variables studied. The hybrids M4, M5 and 3-D HT were noteworthy because of the greater number of commercial ears and for being the most efficient and responsive to the use of nitrogen fertilization.