Effect of scarification and stratification on the in vitro germination of Aristotelia chilensis (Molina) Stuntz

Abstract

Two in vitro assays were performing in order to improve Aristotelia chilensis germination rate. Scarification was tested in the first assay and compare to a control. In the second assay, cold stratification was applied during 2, 4, 6 and 8 weeks at 4 °C in darkness, plus an unstratified control. Seeds were germinated on Petri dish containing water and agar (WA), and incubated for 60 days in a controlled atmosphere at 25 ± 2 °C using cold white fluorescent light tubes (50 μmol m^-2 s^-1 light intensity), under a photoperiod of 16 h light and 8 h of darkness. All treatments achieved higher average germination rates than the control. The highest germination rate was obtained with scarification (G_máx, 92%) though the fastest growth was achieved with 8 weeks of stratification, reaching the lowest average germination time of 18 days. The results demonstrate that A. chilensis seeds present a moderate level of primary dormancy, both exogenous and endogenous.