Sweet corn seeds, compared to those of the common corn, have, in general, a thinner pericarp, which makes them more susceptible to mechanical damages. A study concerning the maturation process of sweet corn seeds was carried out to determine the ideal harvesting point in order to obtain high quality seed, as well as to evaluate the performance of the seeds when harvesting is delayed. Sowing was accomplished on December and harvests carried out on February and March. The first harvesting was performed 26 days after flowering (DAF), when approximately 50% of the plants showed female flowering. The other harvests were accomplished at 7-day intervals, until 96 DAF. After harvest, the seeds were hand threshed, moisture content and dry matter were determined, and a visual evaluation for the presence of the black layer was made. After the last harvest, physiological quality of the seeds was determined by germination, modified cold, accelerated aging and electrical conductivity tests. The harvesting of the Doce Cristal sweet corn cultivar should be accomplished from the 47th to the 75th DAF in order to obtain seeds of high physiological quality. The black layer is an efficient visual characteristic for identification of their physiological maturity.
physiologic maturation; germination; vigor; Zea mays L
