Indicadores de maturidade fisiológica de sementes de ipê-roxo (Tabebuia impetiginosa (Mart.) Standl.)

Abstract

This research determined physiological maturity indicators in Tabebuia impetiginosa seeds. In the period of August 6th until October 6th, eight collections were made in trees located in the Federal University of Lavras – UFLA, Minas Gerais State and in its surroundings. After collections, water content, dry matter, fruits and seeds color; percentage of radicle emission; normal and abnormal seedlings; deteriorated seeds and germination index (GI) were determined. The results obtained showed that when the fruits started the dehiscence they present green color with purple points. The seeds showed green-brownish-yellow color. At this point, the water content in the fruit and in the seeds was 69.02% and 50.98%, respectively. The fruit and seeds dry matter were, respectively, 30.98g/100g and 49.02g/100g of fresh matter. The percentage of radicle emission was 73%; normal seedlings 53%, abnormal seedlings 20%; deteriorated seeds 27%; and GI 2.29%. The presence of cracks and green spots with purple points in the fruits and green-brownish-yellow color in the seeds are good practical indicators to determine the time of harvesting Tabebuia impetiginosa seeds.