Produção e qualidade fisiológica de sementes de milho sob limitações de água no solo

Abstract

In order to obtain the maximum productive potential of a crop, the water availability is one of the main factors for the success of the production. In view of the above, the objective was to evaluate the production and physiological quality of seeds of maize hybrids under water limitations in the soil. The experiment was conducted from March to October 2017 in two stages, in the field, in the Experimental area located at the Unimontes Campus in Janaúba, MG, and the second stage, in the Laboratory of Analysis of Seeds, Unimontes. Five upper boundary conditions of soil water replenishment based on field capacity (100, 85, 70, 55 and 40%) were established, providing controlled soil water conditions to two maize hybrids (2B587 and DKB 390 ), in the scheme of subdivided parcels, leaving the replacements in the parcels. The experimental design was in randomized blocks, with four replications. Biometric and production evaluations were performed at the time of the field experiment. Subsequently, the seeds produced were sent to the laboratory for evaluation of their physiological quality. The following characteristics were evaluated: water content, germination, first germination count, seedling emergence, emergency speed index, accelerated aging, modified electrical and cold conductivity. The data were submitted to statistical analysis. Under conditions of water restriction, the productivity of the corn hybrids studied is negatively affected. Hybrids behaved similarly under water limitations in the soil. Even with the reduction in growth and productivity, the hybrids were tolerant to the water deficit and could be an alternative crop for edaphoclimatic conditions in the North of Minas Gerais. The DKB 390 hybrid expressed better physiological potential. The reduction of soil water availability negatively affected the physiological quality of maize seeds produced.