CRESCIMENTO E PRODUTIVIDADE DO MILHO (Zea mays L.) CULTIVAR BR 206 EM FUNÇÃO DE DOSES DE FÓSFORO EM UM ARGISSOLO VERMELHO AMARELO

Abstract

The Corn (Zea mays L.) currently stands out as one of the world's leading cereals. Even in this scenario, the state of Ceará has shown a relatively small participation in the national production of maize, this fact can be attributed in part to the low level of technology used by most producers, where most do not make use of new technologies Such as fertilization and irrigation. The main consequence of producing under extreme conditions and not carrying out an adequate management of soil fertility are results of low final yield of the crops, with a below average productivity, since the production system adopted does not meet the real needs of the Plants. In order to improve cultivation systems in the state of Ceará, the present study aimed to evaluate the developmental characteristics of the cultivar hybrid corn BR 206 in response to phosphorus doses in a red-yellow Argisol. The experimental design was randomized blocks with five treatments and five replicates. The treatments consisted in the application of 5 doses of phosphorus (0, 50, 100, 150 and 200 kg ha-1). The evaluations consisted of plant height (AP); Diameter of the second internode (ISD); Number of leaves (NF); 100 grain mass (M100); Spike mass (WEM); Grain yield and yield index. The results showed that there was no significant difference for the plant height variable in relation to the P levels, but a significant effect was observed with the quadratic response model for the variables of the second internode, number of leaves, mass of 100 grains and mass Of the ear with respect to the applied P. There was a quadratic response of productivity to the levels of P applied to the soil, with maximum efficiency at the dose of 123.47 kg ha-1 of phosphorus, for a maximum yield of 3,338 kg ha-1 of grains.