Germinação de sementes de Caesalpinia leiostachya (benth.) ducke (pau-ferro) classificadas pelo tamanho e pela forma
Carregando...
Data
2010-04-01
Autores
Biruel, Rosangela Peres [UNESP]
Paula, Rinaldo Cesar de [UNESP]
Aguiar, Ivor Bergemann de [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Sociedade de Investigações Florestais
Resumo
Caesalpinia leiostachya (Benth.) Ducke (pau-ferro) é uma leguminosa arbórea nativa do Brasil, cujas sementes são de diferentes tamanhos e formas, apresentando dormência imposta pela impermeabilidade do tegumento à água. Objetivando melhorar a qualidade do lote, as sementes foram classificadas pela largura em peneiras de crivos circulares (números 13, 14, 15, 16 e 17) e a seguir separadas manualmente pela forma em alongadas, arredondadas e angulares. Foi determinada a massa de 1.000 sementes, medida a espessura de cada classe de largura e forma e investigada a permeabilidade do tegumento em função da largura das sementes. As sementes foram escarificadas em ácido sulfúrico concentrado e submetidas ao teste de germinação, sendo avaliados a porcentagem final e o índice de velocidade de germinação. A classificação das sementes melhorou a qualidade do lote, e a largura das sementes não afetou a permeabilidade do tegumento. As sementes alongadasachatadas são de baixa qualidade fisiológica e devem ser descartadas. As sementes alongadas e angulares tiveram comportamento germinativo similar, e as sementes arredondadas tiveram maior espessura e melhor qualidade fisiológica. A massa de 1.000 sementes, a capacidade germinativa e a velocidade de germinação aumentaram com a largura das sementes.
Caesalpinia leiostachya (Benth.) Ducke (Caesalpiniaceae) is a Brazilian legumenous tree whose seeds present different sizes and shapes, with dormancy imposed by a waterproof coat. In order to improve that quality of lot, seeds were classified by width in sieves of circular meshes (13, 14, 15, 16 and 17) and manually separated by shape in elongate, round and angular. Masses of 1000 seeds were determined and the thickness of each width and shape seedclass was measured, and coat permeability of the seeds classified by the width was investigated. Seeds were scarified in concentrated sulphuric acid and submitted to the germination test. Both final percentage and speed of germination index were evaluated. The classification of the seeds improved the quality of the lot, and the coat permeability was not affected by seed width. Elongated-flat seeds are of low physiological quality and should be discarded. Masses of 1000 seeds, percentage final and speed of germination increased with the width of the seeds. Both elongated and angular seeds had similar germinative behavior, and round seeds are of greater thickness and of superior physiological quality.
Caesalpinia leiostachya (Benth.) Ducke (Caesalpiniaceae) is a Brazilian legumenous tree whose seeds present different sizes and shapes, with dormancy imposed by a waterproof coat. In order to improve that quality of lot, seeds were classified by width in sieves of circular meshes (13, 14, 15, 16 and 17) and manually separated by shape in elongate, round and angular. Masses of 1000 seeds were determined and the thickness of each width and shape seedclass was measured, and coat permeability of the seeds classified by the width was investigated. Seeds were scarified in concentrated sulphuric acid and submitted to the germination test. Both final percentage and speed of germination index were evaluated. The classification of the seeds improved the quality of the lot, and the coat permeability was not affected by seed width. Elongated-flat seeds are of low physiological quality and should be discarded. Masses of 1000 seeds, percentage final and speed of germination increased with the width of the seeds. Both elongated and angular seeds had similar germinative behavior, and round seeds are of greater thickness and of superior physiological quality.
Descrição
Palavras-chave
Semente florestal, Beneficiamento, Qualidade fisiológica, Tree seed, Processing, Physiological quality
Como citar
Revista Árvore. Sociedade de Investigações Florestais, v. 34, n. 2, p. 197-204, 2010.