Viabilidade de sementes de Sebastiania commersoniana (Baill.) Smith & Downs (branquilho) - Euphorbiaceae - pelo teste de tetrazólio

Abstract

3 Unesp-FCAV. Engenheira Agronoma, Ms. em Agronomia (Producao e Tecnologia de Sementes). 4 Unesp-FCAV, Departamento de Biologia Aplicada a Agropecuaria. Bolsista do CNPq. 5 Unesp-FCAV. Doutoranda do Programa de Pos-graduacao em Agronomia (Genetica e Melhoramento de Plantas). Abstract SANTOS, S. R. G. dos; PAULA, R. C. de; FOGACA, C. A.; Fabiola Vitti MORO; COSTA, R. S. Seed viability of Sebastiania commersoniana (Baill.) Smith & Downs (Euphorbiaceae) by the tetrazolium test. Cientifica, Jaboticabal, v.34, n.1, p.39-45, 2006. With the objective of finding the best conditions to test the viability of Sebastiania commersoniana seeds by means of the tetrazolium (TZ) test, an experiment was set up in which the seeds of three lots were submitted to two pre-conditioning periods (3 and 5 hours) at 30 oC, four TZ solution concentrations (0.05, 0.075, 0.1, and 0.2%) and two periods of immersion of the seeds in the TZ solution (2 and 4 hours). The results of the TZ tests were compared to those of a standard germination test and this showed the combination of a pre-conditioning period of 3 h, a 0.1% concentration TZ solution and an immersion period of the seeds in the TZ solution of 2 hours will yield the best results. A 0.05% TZ solution would require an immersion period of 4 hours. In addition to this the external and the internal morphology of the seeds were described.