Efeito de época de semeadura na qualidade fisiológica e sanitária de sementes de soja em dois locais de Mato Grosso do Sul na safra 2004/2005

Abstract

The selection of appropriate areas for the production of soybean seeds of high quality requires inquiry studies, especially in tropical regions. Some researchers believe that in the biggest part of the region of the Cerrados, in the Central Brazil, the climatic conditions are not favorable to the production of soybean seeds with good quality, once the quality of the seeds is highly influenced by the climatic conditions under which they had been produced. The objective of this work was to evaluate the physiological and sanitary quality of seeds of six soybean cultivars at four sowing dates in Ponta Porã and Maracaju, Mato Grosso do Sul, Brazil. The physiological quality of the seeds was evaluated by the tetrazolium test and the standard germination test and the sanitary quality by the Blotter test. The temperature and precipitation were registered during the experimental period. The seeds produced in Ponta Porã presented better physiological quality that the ones produced in Maracaju. The reduced precipitations and the high temperatures during the reproductive phase of the cultivars plants in both places had favored the low pathogen incidence in the seeds. It was not possible to establish the best sowing date for harvest of seeds with better physiological and sanitary quality.