Germination ecology of seeds of endemic species

The phenology of Deginia velebitica seeds, including such topics as maturation, dispersal and germination times, is still largely unknown. For the purpose of the present research, the seeds were collected in the Botanical Garden, Faculty of Science, University of Zagreb and in the natural habitat (above Sibinj, Veliki vrh, Velika kapela mountain) at the time of natural dispersal. Freshly matured and collected seeds were placed under natural conditions (16–28 °C), at room temperature (24 °C), 21 °C and in greenhouse conditions (22/31 °C). Some of the seeds were placed at 5 °C for 3, 6, 9, 12 weeks and checked to see if cold stratification was needed. The most interesting part for the study of germination phenology was the exposure of the seeds to temperature conditions similar to those in na-ture (in the garden) and the definition of maximum and minimum temperatures of germi-nation. Seed dispersal begins soon after maturation and all seeds (100%) are dispersed in one season. After 28 days, low percentages of germination, of 8.77 % (at 24 °C), 6.66 % (at 21 °C), 14.55 % (at 22–31 °C) and 0 % (at 16–28 °C) were found, indicating non-deep physiological dormancy (PD) in Degenia seeds. Non-deep PD is broken by cold stratifica-tion and by seeds being stored dry at room temperature (afterripening). The highest per-centage of germination was at 22–31 °C, and the lowest at 21 °C indicating that Degenia velebitica germinates in late summer or early autumn. Seeds do not require light for ger-mination, but germination in the light is 54 % better at 22–31 °C, 35 % at room temperature and 7 % better at 16–28 °C than in the dark. The seeds collected in the Botanical Garden germinated 18%, 28 % and 30 % better at 22–31 °C, 16–28 °C than seeds collected near the place called Bile after 63 days of germination