Seed germination of Phillyrea angustifolia L., a species of difficult propagation

Sara Mira, Alberto Arnal, Félix Pérez-García


Aim of study: The purpose was to determine the type of dormancy and the optimal germination conditions of Phillyrea angustifolia (Oleaceae) seeds.

Area of study: Germination requirements of P. angustifolia seeds collected from wild plants growing in the province of Ávila (Central Spain) were studied.

Materials and methods: Seed water uptake was measured. Seeds with and without an endocarp were germinated at different temperatures, and several treatments were tested.

Main results: The lignified endocarp interferes mechanically with the emergence of the radicle, and the treatments that achieved the highest germination percentages were the total removal of the endocarp with pliers (84%) or the immersion in liquid nitrogen for 1 min (97%). Scarification with concentrated sulphuric acid did not significantly increase germination compared to the control seeds, and treatments with dry heat or wet heat were detrimental to seed germination. The optimum temperature for germination was 15 ºC. A pre-sowing treatment of soaking in distilled water for 24 h slightly increased germination speed. Neither cold stratification at 5 ºC nor soaking in a gibberellic acid solution improved seed germination.

Research highlights: Phillyrea angustifolia seeds have physiological dormancy – that is, the embryo does not have enough growth potential to overcome the mechanical restriction of the lignified endocarp. The seeds do not exhibit physical dormancy, given their water-permeable lignified endocarp. Our results suggest that the optimum germination protocol for P. angustifolia would be the total removal of the endocarp or immersion in liquid nitrogen for 1 min, followed by immersion in distilled water for 24 h and then seed incubation at 15 ºC in light or darkness.


Oleaceae; physical dormancy; physiological dormancy; seed scarification; stony endocarp

Full Text:



Andrés C, 2011. Phillyrea L. In: Flora Iberica, Vol. 11; Castroviejo S, Aedo C, Cirujano S, Laínz M, Montserrat P, Morales R, Mu-oz F, Navarro C, Paiva J, Soriano C (eds). pp: 139–143. Real Jardín Botánico de Madrid, CSIC, Spain.

Bacchetta G, Bueno A, Sánchez G, Fenu G, Jiménez-Alfaro B, Mattana E, Piotto B, Virevaire M, 2008. Anexo digital I. In: Conservación ex situ de plantas silvestres (Ex situ conservation of wild plants). Principado de Asturias/La Caixa, Spain.

Ballesteros D, Meloni F, Bacchetta G, 2015. Manual for the propagation of selected Mediterranean native plant species. Ecoplantmed, ENPI, CBC-MED.

Baskin CC, Baskin JM, 2014. Seeds: ecology, biogeography and evolution of dormancy and germination (2nd edition). Academic Press, San Diego, CA, USA.

Baskin JM, Baskin CC, 2004. A classification system for seed dormancy. Seed Sci Res 14: 1–16.

Baskin CC, Zackrisson O, Baskin JM, 2002. Role of warm stratification in promoting germination of seeds of Empetrum hermaphroditum (Empetraceae), a circumboreal species with a stony endocarp. Am J Bot 89: 486–493.

Blondel J, Aronson JY, Bodiou G, Boeuf J, 2010. The Mediterranean region. Biological diversity in space and time (2nd edition). Oxford University Press, Oxford, UK.

Catalán G, 1991. Phillyrea. In: Semillas de árboles y arbustos forestales (Forest Tree and Shrub Seeds). pp: 265–266. Instituto Nacional para la Conservación de la Naturaleza, Spain.

Chaves MM, Pereira JS, Maroco J, Rodrigues ML, Ricardo CPP, Osorio ML, Carvalho I, Faria T, Pinheiro C, 2002. How plants cope with water stress in the field? Photosynthesis and growth. Ann Bot 89: 907–916.

Christensen JH, Hewitson B, Busuioc A, Chen A, Gao X, Held I, Jones R, Kolli RK, Kwon WT, Laprise R et al., 2007. Regional climate projections. In: Climate change 2007: the physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change; Solomon S et al. (eds). pp: 847–940. Cambridge University Press, UK.

Copete E, Herranz JM, Copete MA, Ferrandis P, 2014. Interpopulation variability on embryo growth, seed dormancy break and germination in the endangered Iberian daffodil Narcissus eugeniae (Amaryllidaceae). Plant Spec Biol 29: 72–84.

Correia I, Santos L, Faria C, Nobrega C, Almeida H, David T, 2014. Cone-to-seedling variation between Pinus pinaster provenances from contrasting altitudes. Forest Sci 60: 724–732.

Cuneo P, Offord CA, Leishman MR, 2010. Seed ecology of the invasive woody plant African olive (Olea europaea subsp. cuspidata): implications for management and restoration. Aust J Bot 58: 342–348.

De Marco A, Gentile AE, Arena C, De Santo AV, 2005. Organic matter, nutrient content and biological activity in burned and unburned soils of a Mediterranean maquis area of southern Italy. Int J Wildland Fire 14: 365–377.

García-Fayos P, Gulias J, Martínez J, Marzo A, Melero JP, Traveset A, 2001. Bases ecológicas para la recolección, almacenamiento y germinación de semillas de Especies de uso forestal de la comunidad valenciana (Ecological basis for forest tree seed collection, storage and germination of the valencian community). IMEDEA, Banc de Llavors Forestals, Comunidad Valenciana, Spain.

Gómez-Aparicio L, Zamora R, Gómez JM, Hódar JA, Castro J, Baraza E, 2004. Applying plant facilitation to forest restoration: a meta-analysis of the use of shrubs as nurse plants. Ecol Appl 14: 1128–1138.

Grande D, Mancilla-Leyton JM, Delgado-Pertinez M, Martin-Vicente A, 2013. Endozoochorus seed dispersal by goats: recovery, germinability and emergence of five Mediterranean shrub species. Span J Agric Res 11: 347–355.

Herranz JM, Ferrandis P, Copete MA, Duro EH, Zalacain A, 2006. Effect of allelopathic compounds produced by Cistus ladanifer on germination of 20 Mediterranean taxa. Plant Ecol 184: 259–272.

Herrera CM, Jordano P, Guitián, Traveset A, 1998. Annual variability in seed production by woody plants and the masting concept: reassessment of principles and relationship to pollination and seed dispersal. Am Nat 152: 577–594.

Herrera CM, Jordano P, Lopezsoria L, Amat JA, 1994. Recruitment of a mast-fruiting, bird-dispersed tree-bridging frugivore activity and seedling establishment. Ecol Monogr 64: 315–344.

ISTA, 2009. International rules for seed testing. International Seed Testing Association, Switzerland.

Keyes CR, Manso González R, 2015. Climate-influenced ponderosa pine (Pinus ponderosa) seed masting trends in western Montana, USA. For Syst 24(1): e-021.

Kigel J, 1995. Seed germination in arid and semiarid regions. In: Seed development and germination; Kigel J, Galili G (eds). pp. 645–699. Marcel Dekker, New York, USA.

Lazar SL, Mira S, Pamfil D, Martínez-Laborde JB, 2014. Germination and electrical conductivity tests on artificially aged seed lots of two wall-rocket species. Turk J Agric For 38: 857–864.

Lloret F, Penuelas J, Ogaya R, 2004. Establishment of co-existing Mediterranean tree species under a varying soil moisture regime. J Veg Sci 15: 237–244.

Mariotti A, Zeng N, Yoon J-H, Artale V, Navarra A, Alpert P, Li LZX, 2008. Mediterranean water cycle changes: transition to drier 21st century conditions in observations and CMIP3 simulations. Environ Res Lett 3: 4.

Mira S, Estrelles E, González-Benito ME, 2015a. Effect of water content and temperature on seed longevity of seven Brassicaceae species after 5 years storage. Plant Biol 17: 153–162.

Mira S, Veiga-Barbosa L, Pérez-García F, 2015b. Seed germination characteristics of Phillyrea angustifolia L. and P. latifolia L. (Oleaceae), two Mediterranean shrub species having lignified endocarp. Ann For Res 58: 27–37.

Mira S, Estrelles E, González-Benito ME, Corbineau F, 2011a. Biochemical changes induced in seeds of Brassicaceae wild species during ageing. Acta Physiol Plant 33: 1803–1809.

Mira S, González-Benito ME, Ibars AM, Estrelles E, 2011b. Dormancy release and seed ageing in the endangered species Silene diclinis. Biodivers Conserv 20: 345–358.

Moreno JM, Zavala G, Martín M, Millán A, 2010. Forest fire risk in Spain under future climate change. In: Atlas of biodiversity risk; Settele J, Georgiev T, Grabaum R, Grobelnik V, Hammen V, Klotz S, Kotarac M, Kuehn I. (eds). pp: 6–7. Pensoft Publishers, Bulgaria.

Moriondo M, Good P, Durao R, Bindi M, Giannakopoulos C, Corte-Real J, 2006. Potential impact of climate change on fire risk in the Mediterranean area. Clim Res 31: 85–95.

Ne'eman G, Izhaki I, 1999. The effect of stand age and microhabitat on soil seed banks in Mediterranean Aleppo pine forests after fire. Plant Ecol 144: 115–125.

Orsenigo S, Mondoni A, Rossi G, Abeli T, 2014. Some like it hot and some like it cold, but not too much: plant responses to climate extremes. Plant Ecol 215: 677–688.

Parra A, Ramirez DA, Resco V, Velasco A, Moreno JM, 2012. Modifying rainfall patterns in a Mediterranean shrubland: system design, plant responses and experimental burning. Int J Biometeorol 56: 1033–1043.

Pausas J, Llovet J, Rodrigo A, Vallejo R, 2008. Are wildfires a disaster in the Mediterranean basin? A review. Int J Wildland Fire 17: 713–723.

Pérez-García F, Varela F, González-Benito ME, 2012. Morphological and germination response variability in seeds of wild yellow gentian (Gentiana lutea L.) accessions from northwest Spain. Botany 90: 731–742.

Piotto B, Di Noi A, 2003. Propagazione per seme di alberi e arbusti della flora Mediterranea (Seed propagation of Mediterranean trees and shrubs). Agenzia Nazionale per la Protezione dell'Ambiente (ANPA), Rome, Italy.

R Core Team, 2015. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. [5 December 2014].

Ritz C, Streibig JC, 2005. Bioassay analysis using R. J Stat Softw 12: 5.

Ritz C, Pipper CB, Streibig JC, 2013. Analysis of germination data from agricultural experiments. Eur J Agron 45: 1–6.

Semillas Silvestres S.L. 2010. Phillyrea angustifolia L. [5 December 2014].

Takos IA, Efthimiou GS, 2003. Germination results on dormant seeds of 15 tree species autumn sown in a northern Greek nursery. Silvae Genet 52: 67–71.

Thanos CA, Kadis CC, Skarou F, 1995. Ecophysiology of germination in the aromatic plants thyme, savory and C. ladanifer. Int J Wildland Fire 2: 15–20.

Thanos CA, Georghiou K, Kadis CC, Pantazi C, 1992. Cistaceae: a plant family with hard seeds. Israel J Bot 41: 251–263.

Thomas PA, Garcia-Marti X, 2015. Response of European yews to climate change: a review. For Syst 24(3): eR01.

Traveset A, Rodríguez-Pérez J, Pias B, 2008. Seed trait changes in dispersers' guts and consequences for germination and seedling growth. Ecology 89: 95–106.

Traveset A, Robertson QW, Rodríguez-Pérez J, 2007. A review on the role of endozoochory in seed germination. In: Seed dispersal, theory and its application in a changing world; Dennis AJ, Schupp EW, Green RA, Westcott DA (eds). pp. 78–103. CABI International, UK.

Vilmorin, 2013. Phillyrea latifolia. semillas/arbustos/entry-Phillyrea latifolia. [24 July 2013].

Vitale M, Capogna F, Manes F, 2007. Resilience assessment on Phillyrea angustifolia L. maquis undergone to experimental fire through a big-leaf modelling approach. Ecol Model 203: 387–394.

Young JA, Young CG, 1992. Seeds of woody plants in North America. Dioscorides. Portland, OR, USA.

Yucedag C, Gultekin HC, 2011. Effects of fruit collection date on Phillyrea latifolia L. seed germination. Pak J Biol Sci 14: 785–787.

DOI: 10.5424/fs/2017261-10216