GROWTH AND YIELD OF CORN GRAIN AND GREEN EAR IN COMPETITION WITH WEEDS

Studies on plant growth are interesting because they provide explanations for the factors that influence yield in various crops. The objective of this work was to evaluate growth and yield in corn cultivar AG 1051, when in competition with weeds. Cultivar AG 1051 was submitted to two groups of treatments: weed control, and sampling periods for dry biomass evaluation. The weed control treatments consisted of hoeing (two hoeings performed at. 20 and 40 days after sowing) and no hoeing. Sampling periods consisted of collecting the aboveground part and roots of corn every fifteen clays, until 105 days after sowing (DAS); the first sampling was performed 30 DAS. A completely randomized block design with ten replicates was used. For the characteristics evaluated in a single season, statistical analyses were carried out as a random block experiment. For the characteristics evaluated in several periods. carried out as random blocks with split-plots (weed control assigned analyses were can to plots). Fourteen weed species, unevenly distributed throughout the experimental area. were the most important. The growth observed for the above-ground part and root system of corn was 30% smaller in the non-hoed plots, compared to the hoed plots. Lack of weed control increased dry matter of the above-ground part of the weeds and reduced the number of unhusked and husked marketable green cars by 23% and 49%, respectively. Grain yield reduction caused by lack of weed control reached 38%.