Chemical Applications, Scarification and Stratification Effects on Seed Germination of Rare Endemic Verbascum calycosum Hausskn. ex Murb. (Scrophulariaceae)



Verbascum calycosum is an endemic plant species having considerable narrow distribution in Erzincan (Turkey) region. This species is known from only a single population and its habitats are highly threatened due to intensive human activities and soil erosion. In this study, the germination behavior of V. calycosum under different concentrations of NaCl, HCl, KNO3, GA3 (100 and 200 μM), hot-cold stratification and mechanical scarification were investigated. Seeds were exposed to a photoperiod of 8 h light/16 h dark with a 23/18 °C thermoperiod. Germination rates increased with GA3-100 µM (39%), GA3-200 µM (54.5%), mechanical scarification (34.5%) and cold stratification treatments (+4 °C, 23.25%; -20 °C, 18.25%) on the other hand, KNO3, NaCl, HCl and stratification with hot water treatments have decreased germination rates significantly when compared to the control (12.25%). Increased germination after GA3 application and mechanical scarification indicated that seeds of V. calycosum exhibited both non-deep and intermediate physiological dormancy as well as physical dormancy due to its hard seed coat. The highest speed of germination index was obtained at cold stratification of +4 °C and -20 °C (10.3). This study represents first report about seed dormancy and germination characteristics of V. calycosum. Overall, these results will provide valuable data for ex situ conservation of this rare endemic plant.


dormancy; endemic; ex situ; germination; Scrophulariaceae; Verbascum

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Asaadi AM, Heshmati G, Dadkhah A (2015). Effects of Different Treatments to Stimulate Seed Germination of Salsola arbusculiformis Drob. Ecopersia 3:1077-1088.

Asl MB, Sharivivash R, Rahbari A (2011). Effect of different treatments on seed germination of honey locust (Gleditschia triacanthos). Modern Applied Science 5:200-204.

Aytaç Z, Karaveliogullari FA, Ekici M (2005). Yok olan tur (EX) ve yetersiz veri (DD) basamaginda bulunan bazi taksonlar ile ilgili veriler [Data about some taxa of the missing species (EX) and inadequately framed (DD)]. Ot Sistematik Botanik Dergisi 12(1):9-20.

Bonner FT (1974). Seed testing in Seed of woody plants in the United States. Agriculture handbook No. 450 Service USDA, Washington, USA.

Bu H, Du G, Chen X, Xu X, Liu K, Wen S (2008). Community wide germination strategies in an alpine meadow on the eastern Qinghai-Tibet plateau: phylogenetic and life-history correlates. Plant Ecology 195:87-98.

Choudhury BI, Khan ML, Das K (2009). Seed dormancy and germination in Gymnocladus assamicus: an endemic legume tree from Northeast India. Seed Science and Technology 37:582-588.

Corbineau F, Bagniol S, Côme D (1990). Sunflower (Helianthus annuus L.) seed dormancy and its regulation by ethylene. Israel Journal of Botany 39:313-325.

Cousins SR, Witkowski ETF, Mycock DJ (2014). Seed storage and germination in Kumara plicatilis, a tree aloe endemic to Mountain Fynbos in the Boland, south-western Cape, South Africa. South African Journal of Botany 94:190-194.

Davis PH (1978). Flora of Turkey and the East Aegean Islands, Vol 6. Edinburg.

Ekim T, Koyuncu M, Vural M, Duman H, Aytaç Z, Adiguzel N (2000). Red data book of Turkish plants (ferns and seed plants). Publications of Association of Turkey’s Nature Conservation, Ankara.

Erik S, Tarikahya B (2004). Turkiye florasi uzerine [Flora of Turkey]. Journal of Kebikec 17(1):139-163.

FAO (1983). Handbook on seeds of dryzone acacias (based on the work of Doran JC et al.). Rome.

Farooq M, Basra SMA, Hafeez K, Ahmad N (2005). Thermal hardening: a new seed vigor enhancement tool in rice. Journal of Integrative Plant Biology 47:187-193.

Hilhorst HWM, Karssen CM (1992). Seed dormancy and germination: the role of abscisic acid and gibberellins and the importance of hormone mutants. Plant Growth Regulation 11:225-238.

Hilooglu M (2016). Determination of threatening ecological and genetic factors for some endemic plant species distributed in Erzincan. PhD Thesis, Anadolu Univ, Turkey.

ISTA (International Seed Test Association) (1985). The germination test. Seed Science and Technology 13:307-463.

Jones CD, Stevens MR, Jolley VD, Hopkins BG, Jensen SL, Turner D, Stettler JM (2016). Evaluation of thermal, chemical, and mechanical seed scarification methods for 4 Great Basin lupine species. Native Plants Journal 17:5-17.

Kandemir A, Makbul S (2004). Erzincan yoresinde yayilis gosteren bazi nadir bitki turleri uzerine gozlemler [The observations on some rare plant species grown up in Erzincan]. Erzincan Egitim Fakultesi Dergisi 6:37-49.

Kandemir A, Sevindi C, Korkmaz M, Celikoglu S (2015). IUCN threatened categories on endemic taxa which is specific to Erzincan (Turkey). Bagbahce Bilim Dergisi 2:43-65.

Katembe WJ, Ungar IA, Mitchell JP (1998). Effect of salinity on germination and seedling growth of two Atriplex species (Chenopodiaceae). Annals of Botany 82:167-175.

Longer DE, Degago Y (1996). Field weathering potential of normal and hardseeded soybean genotypes. Seed Science and Technology 24:273-280.

Luna B, Moreno JM, Cruz A, Fernandez-Gonzalez F (2007). Heat-Shock and seed germination of a group of Mediterranean plant species growing in a burned area: an approach based on plant functional types. Environmental and Experimental Botany 60:324-333.

Menges ES (1986). Predicting the future of rare plant populations: demographic monitoring and modelling. Natural Areas Journal 6:13-25.

Necajeva, J, Ievinsh G (2013). Seed dormancy and germination of an endangered coastal plant Eryngium maritimum (Apiaceae). Estonian Journal of Ecology 62:150-161.

Nydegger-Hugli M (2002). Dreizehnte und letste Erganzungen zu P.H. Davis [Flora of Turkey and the East Aegean Islands]. Bahunia 16:33-35.

Peng DL, Hu XJ, Yang J, Sun H (2017). Seed dormancy, germination and soil seed bank of Lamiophlomis rotata and Marmoritis complanatum (Labiatae), two endemic species from Himalaya-Hengduan Mountains. Plant Biosystems. doi: 10.1080/11263504.2017.1311959.

RBG Kew (2008). Royal Botanic Gardens Kew, Seed Information Database (SID) Ver. 7.1. Retrieved 2017 January from 5

Schemske DW, Husband BC, Ruckelshaus CG, Goodwillie C, Parker IM, Bishop JG (1994). Evaluating approaches to the conservation of rare and endangered plants. Ecology 75:584-606.

Schwienbacher E, Navarro-Cano JA, Neuner G, Erschbamer B (2011). Seed dormancy in alpine species. Flora 206:845-856.

Sfairi Y, Lahcen O, Feddy MNA, Abbad A (2012). Dormancy-breaking and salinity/water stress effects on seed germination of atlas cypress, an endemic and threatened coniferous species in Morocco. African Journal of Biotechnology 11:4385-4390.

Teimouri MS, Mahallati MN (2013). Seed germination and breaking of seed dormancy techniques for endemic Hymenocrater platystegius. International Journal of Agriculture and Crop Sciences 6:885-889.

Vleeshouwers LM, Bowmeester HJ, Karssen CM (1995). Redefining seed dormancy: an attempt to integrate physiology and ecology. Journal of Ecology 83:1031-1037.

Werner JE, Finkelstein RR (1995). Arabidopsis mutants with reduced response to NaCl an osmotic stress. Physiologia Plantarum 93:659-666.

Yildiztugay E, Kucukoduk M (2012). Dormancy breaking and germination requirements for seeds of Sphaerophysa kotschyana Boiss. Journal of Global Biosciences 1:20-27.

Yucel E (2000). Effects of different salt (NaCl), nitrate (KNO3) and acid (H2SO4) concentrations on the germination of some Salvia species seeds. Seed Science and Technology 28:853-860.

Yucel E, Yilmaz G (2009). Effects of different alkaline metal salts (NaCl, KNO3), acid concentrations (H2SO4) and growth regulator (GA3) on the germination of Salvia cyanescens Boiss. & Bal. seeds. Gazi University Journal of Science 22:123-127.

Zheng Y, Sun W (2009). Seed germination of Huagaimu, a critically endangered plant endemic to southeastern Yunnan, China. HortTechnology 1:427-431.

Zhou Z, Bao W (2011). Levels of physiological dormancy and methods for improving seed germination of four rose species. Scientia Horticulturae 129(4):818-824.


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