Determination of the Optimum Moisture Content ofPurple Ipe （Handroanthus heptaphyllus） Seeds forBiospeckle Tests

Handroanthus heptaphyllus （botany synonymy Tabebuia heptaphylla） is considered to have very important economical,ornamental and medicinal value. It is included in the Bignoniaceae botanical family, whose multiplication is quite solely carried byseeds. Forest dispersion elements, i.e., the seeds, deserve a deep understanding on their physiological performance. The objective ofthis research work was to determine the optimum seed moisture content for laser interaction in biospeckle tests, which is based onlaser interferometry. Seeds were hydrated to the level of 69% and then divided into four subsamples, i.e., （1） seeds without teguments,（2） seeds with tegument, （3） seeds without teguments frozen at 0 ℃ and （4） seeds with teguments frozen at 0 ℃. The foursubsamples were then separated into five moisture level groups （28%, 35%, 54%, 63% and 69%） and exposed to the laser. Thebiospeckle phenomenon quantification was carried out by means of the moment of inertia （MI） approach. A positive correlationbetween MI and se