Germination and Viability of Seeds of Caesalpinia pulcherrima Newly Harvested and Stored

Abstract

Caesalpinia pulcherrima is an exotic shrub species, belonging to the Fabaceae family, that has medicinal properties, and is widely used for urban afforestation. The objective of this research was to evaluate the overcoming of the C. pulcherrima seed dormancy, the influence of temperature, storage, and water quantity on the substrate in the germination of the species, as well as the use of the tetrazolium test for viability analysis. The analyzes were carried out at the Plant Propagation Laboratory at the Agricultural Sciences Center of the Federal University of Alagoas, in the municipality of Rio Largo, Brazil, and at the Laboratory of Plant Physiology, Arapiraca Campus, at the same University. The experiments were performed under a completely randomized design, with four replicates of 25 seeds. The results demonstrated that during storage the seeds developed a possible secondary dormancy, which was overcome with a time of twelve months of storage. The C. pulcherrima seeds subjected to the test of light qualities presented a significant difference in their germination percentage when verified with the time of storage. In the far-red quality, the newly harvested seeds had a germination percentage of (98%), higher than seeds with 12 months of storage (80.5%). The water volume 3.5-fold the weight of the dry paper provides (90%) germination when compared to other volumes. The tetrazolium salt concentrations of 0.075% and 0.1%, under the temperature of 30°C within 2 hours, are indicated for the viability analysis of Caesalpinia pulcherrima seeds.