Condicionamento fisiolÃgico em matriz sÃlida durante o armazenamento de sementes de cafà (Coffea arabica L.) em diferentes graus de umidade / Physiological conditioning on solid matrix during storage of coffee seeds (Coffea arabica L.) with different moisture contents

AUTOR(ES)
DATA DE PUBLICAÇÃO

2009

RESUMO

Coffee seeds present poor storability with vigor loss in few months, which limits its use, restricting the seedling-producing time. The physiological conditioning or priming is a technique which is intended to promote improvement in seed performance. Evaluating the effect of different temperatures and periods of time in the physiological conditioning of solid matrix upon the physiological Coffea arabica L. seed quality stored with different moisture contents was the objective in this thesis work conducted in the Central Laboratory of Seeds at Federal University of Lavras (Universidade Federal de Lavras MG) from 2006 to 2008. Seeds with three moisture contents (13.0; 24.0 and 36,0% wb), classified , treated, packed in Kraft paper packages, wrapped by sealed polyethylene packages and stored in cold room for 0, 3, 6, 9 and 12 months were used. After each storage time, the seeds were submitted to conditioning and evaluated immediately. The trials for the moisture content were conducted in randomized blocks with 50 treatments arranged in a factorial scheme 5x3x3+5, and four replicates. Conditioning was conducted involving the seeds with endocarp into commercial organic substrate with moisture of 100% of the water holding capacity. The seeds involved by the solid matrix were maintained on plastic trays inside the BOD type chambers at 20, 30 and 40 + 1oC for 2, 4 and 6 days. After evaluation, it was concluded there was increase in the germination percentage, emergence speed index and vigor, mainly in the seeds with initial moisture content of 24.0 and 36.0%. Conditioning at 40ÂC harmed the performance of the seeds. The temperature of 30ÂC is the most adequate temperature for all the time periods studied. Conditioning is more efficient for seeds of poorer physiological quality, interfering in the activities of enzymes SOD, CAT, MDH and ADH, above all, of the former and promotes the expression of heat-resistant proteins of different molecular weights.

ASSUNTO(S)

fitotecnia vigor protein pattern priming vigor padrÃes protÃicos priming

ACESSO AO ARTIGO

Documentos Relacionados