Seleção de matrizes de tabebuia caraiba (Mart.) bureau com base na qualidade fisiológica de sementes

Abstract

Craibeira (Tabebuia caraiba (Mart.) Bureau) is a naturally occurring forest species in the Caatinga, Cerrado and Agreste of the Northeast, widely used for reforestation and landscaping, which, despite having great importance, still lacks studies on seed production, being necessary to develop conservation strategies. Among these, the selection of mother trees can be important to obtain seeds with physical, physiological and genetic quality. Given its importance, the objective of this work was to evaluate the physical and physiological quality of T. caraiba seeds from different matrices in two areas of Cariri, Paraíba, aiming at the selection and production of plants with high standards. The field study was conducted in the cities of São João do Cariri and Sumé - PB. In each area, fruits were collected from 20 matrix trees, which were taken to the Seed Analysis Laboratory (LAS) of the UFPB Agricultural Sciences Center, where the processing and production of lots by matrix were carried out. Therefore, the variables evaluated were: biometry (mm), water content (%), weight of a thousand seeds (g), germination (%), first germination count (%), germination speed index, emergence (% ), emergence speed index, length (cm) and seedling dry mass (g). For statistical analysis, a completely randomized design was used and the means were compared using the Scott-Knott test at 5% probability. Based on the results, the seeds collected from mother trees in the municipalities of São João do Cariri and Sumé, PB showed high variability in terms of length, width and thickness, as well as a high percentage of germination and emergence. We conclude that these seeds have high physiological quality, with the mother trees 4, 11, 16, 17, 19 and 20 located in São João do Cariri, PB, as well as those coming from Sumé, PB (1, 8, 9, 11 and 19) as the ones with the greatest potential for selection, being able to serve as donors of seeds with a high standard, either for reforestation purposes and/or recomposition of degraded areas.