Germination of Tabebuia chrysotricha (Mart.) Standl. seeds dried in dry chamber, stored in different environments and submitted to seven levels of osmotic potential.

Abstract

The objective of this study was to evaluate the germination percentage of Tabebuia chrysotricha (Mart.) Standl. seeds. The seeds were dried in dry chamber for 72 hours. After drying the seeds were packed and stored in a dry chamber, in a cold chamber and in natural laboratory conditions. The germination was evaluated after 5, 30, 60, 90, 80 and 240 days of storage. The germination tests were performed in germination boxes lined with two sheets of filter paper moistened with distilled water or polyethyleneglycol-6000 solutions (Ys : -0,2; -0,4; -0,6; -0,8 and -,0 MPa). Three replications of 25 seeds were used for each treatment. The germination tests were conducted in germination chamber with 25 °C temperature and photoperiod of 24 hours. Germination counts were done 7, 4 and 2 days after sowing. The germination percentage decreased when seeds were stored under natural laboratory conditions. The results indicated that the germination counts must be performed through periods longer than 7 days. The seeds were not resistant to water stress since their germination decreased sharply under osmotic potentials lower than -0,4 MPa.Additional keywords: water availability; polyethylene glycol - 6000; storage.