Potassium leakage and maize seed physiological potential

Abstract

Seed production usually requires fast decisions to improve the efficacy of seed handling during harvesting, processing and storage. Seed technologists have focused on the development or improvement of procedures which allow rapid and consistent identification of higher quality seed lots. This research verified the effectiveness of the potassium leachate test on the evaluation of the physiological potential of maize seeds in comparison to recommended seed vigor tests. Five seed lots of the hybrid Avant were submitted to the potassium leachate, standard germination, first count, accelerated aging, electrical conductivity, field emergence and cold tests. The amount of potassium leachate was determined after seed imbibition for 30, 60, 90, 120, 150 and 180 minutes, at 25°C; a flame photometer adjusted to 50 mug K+ mL-1 pattern and reading 50 was used to determine the amount of leached potassium. The potassium leachate test consistently ranked the seed lots according to their physiological quality in comparison to other tests, and is a new alternative test for maize seed quality control programs.

Priming effect on the physiological potential of maize seeds under abiotic stress1

“…The following tests were carried out: a) Electrical conductivity: conducted with 4 subsamples of 50 seeds per priming treatment (Miguel & Marcos Filho 2002); b) First germination count and seed germination: consisted of four subsamples of 50 seeds per treatment, using three germitest paper sheets as substrate, moistened with water at the ratio of 3 times the paper dry mass, germinated at 25 ºC, at a 12-h photoperiod (Brasil 2009); c) Seedling emergence: conducted in a greenhouse, using four subsamples of 50 seeds per treatment, sowed at 1 cm depth in trays, using sand as substrate. The rate of emerged seedlings was registered until stand uniformity, being considered emerged the seedlings with shoot length not less than 20 mm.…”

Comparação entre métodos para a avaliação do vigor de lotes de sementes de triticale

“…Após esse período, a condutividade elétrica da solução foi determinada com auxílio de condutivímetro e os valores médios foram expressos em µS cm -1 g -1 de semente (MARCOS FILHO, 2005); 6) teste de lixiviação de potássio: instalou-se utilizandose quatro subamostras de 50 sementes, pesadas e colocadas em copos plásticos, contendo 75mL de água destilada, mantidos a 25ºC por três horas. O cálculo da lixiviação de potássio foi feito pela multiplicação da leitura obtida no fotômetro de chama (µg mL -1 de potássio) pelo volume de água destilada (mL) e dividido pela massa da amostra (g) e os resultados foram expressos em µg mL -1 de potássio/g de semente (MIGUEL & MARCOS FILHO, 2002).…”

“…Ambos os testes possibilitaram resultados satisfatórios para a classificação de lotes de sementes de milho quanto ao vigor, porém o teste de lixiviação de potássio foi mais eficiente e rápido, demandando somente 30 minutos de embebição para a obtenção dos resultados, enquanto para o teste de condutividade elétrica foram necessárias 24 horas (MIGUEL & MARCOS FILHO, 2002).…”

Electrical conductivity for seed vigor test in sorghum (Sorghum bicolor)

“…The potassium leachate test is based on the same principle of the electrical conductivity test with the additional advantage of producing results in a considerable shorter period of time. In addition, it focus on a specific ion, while the electrical conductivity test evaluates a set of electrolytes release (Miguel and Filho 2002. Potassium leachate and electrical conductivity tests yielded similar results in the ranking of physiological potential of seed lots.…”