Tabebuia impetiginosa is a tree of high economic, ornamental and medicinal value and is presently on the list of the Forest Institute of São Paulo as a species in need of genetic preservation ex situ. Thus, the objective of this research was to study the physiological performance of T. impetiginosa seeds with different moisture contents and storage in liquid nitrogen for 360 days. Mature fruits were placed under shade in the laboratory to allow hand seed extraction. The initial moisture content of the seed lot was then determined and a portion of it was removed that had the highest degree of moisture (treatment) to be studied, which was 18.3%. The remaining seeds were submitted to drying in a forced air circulation dryer at 30ºC in order to obtain the other degrees of moisture (12.5, 8.4 and 4.2%). The seed portions corresponding to the four moisture contents were stored in liquid nitrogen (-196ºC). They were submitted to physiological evaluations at 0, 120, 240 and 360 days of storage. The experiment was set up in a randomized complete design, with four treatments (moisture degrees) and four replications; means were compared by the Tukey test at 5%. T. impetiginosa seeds can be previously dried to a low degree of moisture (4.2%) and preserved in liquid nitrogen for 360 days.
Tabebuia sp; storage; germplasm bank; physiological quality
