Seed dormancy and reproductive traits of the southern Balkan endemic plants Jancaea heldreichii (Gesneriaceae) and Viola delphinantha (Violaceae)
Year: 2025
Type: article
Abstract: The Mediterranean region presents a significant number of plant species facing threats from habitat loss and climate change, particularly those with limited distribution and habitat scarcity, such as chasmophytes. The study represents the first investigation into the germination potential of Jancaea heldreichii (Gesneriaceae) and Viola delphinantha (Violaceae), shedding light on their seed dormancy characteristics and germination aiming to assist conservation efforts. Fruit capsules of both species were collected, and their seeds were either cold stratified or immersed in hormone solutions prior to a germination test. After the end of the germination test, the ungerminated seeds were subjected to a cutting test and those with a well-developed embryo were subjected to a viability staining test using two different dyes, 2,3,5-triphenyl tetrazolium chloride and Evans blue. The study revealed that hormone treatments, particularly gibberellic acid, significantly increased germination percentages (69.4% and 88.3% for J. heldreichii and V. delphinantha, respectively) compared to control (untreated) seeds. Kinetin also enhanced germination, with a significantly higher increase in J. heldreichii compared to V. delphinantha (50.1% and 6.4%, respectively), whereas cold stratification had a lesser effect (28% and 4.2%, respectively), and the control treatment showed negligible germination. An ungerminated viability test in both species revealed that in the gibberellic acid treatment no ungerminated seeds with a well-developed embryo (stained or unstained) were found, suggesting that all the seeds that could produce normal seedlings were germinated. The study underscores the importance of germination protocols for conserving chasmophytic endemics like J. heldreichii and V. delphinantha. Such protocols are essential for preserving these unique plant species and their habitats. Citation: Varsamis G., Merou Th., Tseniklidou K. & Tsiftsis S. 2025: Seed dormancy and reproductive traits of the southern Balkan endemic plants Jancaea heldreichii (Gesneriaceae) and Viola delphinantha (Violaceae). – Willdenowia 55: 67–77. Version of record first published online on 7 April 2025.
DOI: 10.3372/wi.55.06
Institution: Democritus University of Thrace
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W4409239389