Qualidade fisiológica de sementes de milho sob diferentes condi??es de armazenamento

摘要

This study aims to examine the quality of corn seeds stored under different conditions from May to October, 2008. The experiment was conducted at the Research Laboratory of Seed Analysis of Federal University of Tocantins, Gurupi Campus, with seeds of commercial cultivars of corn obtained in the F2 generation, stored under the environmental conditions of the state of Tocantins, and in cold chamber (20 °C, and relative humidity of 20%). In order to obtain the salt stress, solutions of potassium chloride (KCl) were used in the following concentrations (mol m-3): zero (T1), 30 (T2), 90 (T3), 170 (T4) and 260 (T5). In order to evaluate the quality of seeds, the following tests were made: germination, germination speed index, seed health and seedling length. The experimental design was a randomized complete block with three replications in a factorial 2x5 (storage conditions x concentration of KCl). Subsequent analysis of ANOVA and application of Tukey's test at 5% were carried out. The average percentage of seed germination was 3.86% and 94% for the storage environmental conditions and cold chamber, respectively. At the highest concentration of KCl, seedlings were 18.33 mm seedling-1 shoot length, and at the lowest concentration, the control, 74 mm seedling-1. The results showed that environmental conditions from May to October in Gurupi, state of Tocantins, are not suitable for storage of seed corn without refrigeration.