Assessment of seed viability of 17 high andean tropical species by germination and tetrazolium tests

Abstract

Viability denotes the potential of a seed to germinate, which is linked to the reproductive success or failure of the populations and in this way is one of the first variables to evaluate when working with seeds. Our aim was to determine the best method to assess the viability in 17 high Andean species; the viability obtained by two tests was compared: Tetrazolium, for which variations in concentration, conditioning and exposure time were tested; and germination, which was worked under controlled conditions at 20/10 °C, photoperiod and thermoperiod of 12 hours. The Kruskal-Wallis test was used to evaluate differences. Differences were found between tests. In 11 species the Tetrazolium test is recommended, where the best evaluation condition was [1-1.5 %] TZ, 40 °C and 24 hours of exposure. In Puya, Hypericum, and Gaultheria, the germination was the better test for viability evaluation. The comparison of the tests allowed to detect dormancy in some species where a high viability but low germination was recorded. The results allowed to determine the most reliable method to evaluate the viability in the different species, provide information about their germinative requirements and potential for sexual propagation, as well as detect the possible presence of dormancy and the need to deepen the evaluation of the methods of rupture that allow to increase the percentage of germination in some of the species.