Physiological seed quality of sweet corn seeds as a function of the moisture content at harvest and the drying temperature

Abstract

The purpose of the present research was to study physiological seed quality of sweet corn as a function of water content and drying temperatures of ears at harvesting time. Experiments were made in the Agriculture School of São Paulo State University located in Botucatu, São Paulo, Brazil. Ears of sweet corn cultivar, BR 401 Doce de Ouro (sugary), were harvested at different times, starting at physiological seed maturity, and submitted to different drying temperatures (30o C and 40o C) in an air circulation chamber. After drying, ears were shelled and seeds were stored in paper bags under laboratory environmental conditions. Field dried seeds, with 10.1% of moisture, were utilized as a control. Physiological seed quality for each harvesting date and drying temperature were analyzed before storage and six months after. The following characteristics were utilized: seedling emergency under field condition, speed of seedling emergence, seedling dry matter content, germination, first counting of germination, accelerated ageing test, cold test without soil, electrical conductivity and Ca, Mg, K and Na lixiviated from seeds in the water of the in conductivity test. The following conclusions were drawn: seeds showed a higher sensitivity to drying temperature of 40oC than to 30oC, in the first evaluation, but not after six months of storage. Artificial drying of seeds did not affect seed quality, if harvest occurred between 17.6% and 50.7% of moisture, when compared to field dried harvested seeds.