Qualidade fisiológica e sanitária de sementes de milho colhidas e secas em espigas

Mechanical injuries during harvest and drying processes are considered major problems regarding maize seed quality. The aim of this work was to verify the effects of manual and mechanical harvest and husking of maize ears, simple hybrid 30F80, with hard endosperm, and drying temperatures with respect to sanitary and physiological quality of seed recently harvested and stored for seven months. The moisture content of ears at harvest was 29% and temperatures at drying was 35 oC and 42oC. The experimental design was completely randomized with 12 repetitions. Germination test was performed to assess the viability and the vigor was estimated through several tests: accelerated ageing, cold test, seedling emergence, seedling emergence rate and dry weight of aerial part of seedling. The harvest process of ears did not affect seed quality when the ears were dried at temperature of 35 oC, as shown by the tests applied. Nevertheless, the mechanical harvest and husking affected negatively the seeds when they were dried at the temperature of 42oC, as shown by the tests. Vigor effect on the seeds were detected in two occasions before storage and during germination after seven months of storage. As a conclusion, mechanical harvest and husking followed by drying at high temperatures affect the physiological quality of seeds.