Seeds of five riparian forest tree species from the Rio Grande River basin in the State of Minas Gerais - Brazil were classified according to the physiological storage behavior as a way to provide information for future programs on propagation and ex situ conservation. Seeds of Miconia argyrophylla DC. (Melastomastaceae), Allophylus edulis (A St.-Hil., Cambess. & A. Juss.) Radlk. (Sapindaceae), Ixora warmingii Müll. Arg. (Rubiaceae), Aulomyrcia venulosa DC. (Myrtaceae), and Metrodorea stipularis Mart. (Rutaceae) were collected and taken to the seed laboratory where they were processed and submitted to drying, storage and evaluation of viability by the germination test. After physiological classification regarding storage behaviour it was observed that seeds of M. argyrophylla and M. stipularis presented orthodox behaviour. Such kind of seeds allow storage at low temperature (-20ºC) and moisture content (£5%), without harming viability. On the other hand, seeds of A. edulis, I. warmingii and M. venulosa were classified as recalcitrant, which did not tolerate moisture contents below 12%, indicating that in situ conservation should be used for preservation of the genetic resources of these species.
forest species; sensitivity to desiccation; recalcitrant; orthodox; conservation
