Abstract
Pollen and seed micro-morphological features of six species of Polygala distributed in Iran were examined using light (LM) and scanning electron microscope (SEM). The results show a great pollen morphological variation, which provides helpful data for species delimitation in Polygala. The pollen grains are monad, radially symmetrical, isopolar, polyzonocolporate, medium to large, oblate-spheroidal to prolate-spheroidal in shape. We observed four types of surface sculpture (psilate, psilate to granulate, rugulate-granulate and rugulate) and four types of apocolpial area (psilate with small lumina, reticulate with large lumina, micro-perforate and coarsely regulate and gemmate or granulate with lumina). Moreover, the importance of seed micro-morphological traits in species delimitation have demonstrated based on elaiosome appendages size, number of lobes and their sculpture, seed surface sculpture and trichome type.
References
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<p>Arroyo-Cosultchi, G., Terrazas, T., Arias, S. & Arreola-Nava, H.J. (2006) The systematic significance of seed morphology in <em>Stenocereus</em> (Cactaceae). <em>Taxon</em> 55 (4): 983–992. https://doi.org/10.2307/25065693</p>
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<p>Barthlott, W. (1981) Epidermal and seed surface characters of plants: systematic applicability and some evolutionary aspects. <em>Nordic Journal of Botany</em> 1 (3): 345–355. https://doi.org/10.1111/j.1756-1051.1981.tb00704.x</p>
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<p>Boissier, E. & Heldreich, T. (1853) <em>Diagnoses Plantarum Orientalium novarum </em>ser. 2, 1. Apud B. Herrmann, Lipsiae, 57 pp.</p>
<p>Bojnanský, V. & Fargašová, A. (2007) <em>Atlas of seeds and fruits of Central and East-European flora: The Carpathian Mountains region</em>. Springer Science & Business Media.</p>
<p>Bonilla-Barbosa, J., Novelo, A., Orozco, Y.H. & Márquez-Guzmán, J. (2000) Comparative seed morphology of Mexican Nymphaea species. <em>Aquatic Botany</em> 68 (3): 189–204. https://doi.org/10.1016/S0304-3770(00)00125-X</p>
<p>Bornmüller, J.F.N. & Gauba, E. (1942) <em>Repertorium Specierum Novarum Regni Vegetabilis. Centralblatt für Sammlung und Veroffentlichung von Einzeldiagnosen neuer Pflanzen, </em>51. [Edited by Friedrich Fedde]. Berlin, 33 pp.</p>
<p>Castro, S., Silveira, P., Navarro, L., Paiva, J. & Coutinho, A.P. (2009) Pollen morphology of <em>Chamaebuxus</em> (DC.) Schb., <em>Chodatia</em> Paiva and <em>Rhinotropis</em> (Blake) Paiva (<em>Polygala</em> L., Polygalaceae). <em>Grana</em> 48 (3): 179–192. https://doi.org/10.1080/00173130902938428</p>
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<p>Chrtek, J. & Křísa, B. (1977) <em>Flora Iranica, Family Polygalaceae</em>, No. 124. Akademische Druckund, Graz, pp. 1–11.</p>
<p>Cosson, E.S. (1874) <em>Bulletin de la Société Botanique de France</em>, 20. Paris, 240 pp. https://doi.org/10.1080/00378941.1873.10825518</p>
<p>Cronquist, A. & Takhtadzhi︠a︡n, A.L. (1981) <em>An Integrated System of Classification of Flowering Plants</em>. Columbia university press, pp. 248–250.</p>
<p>Cullen, J. (1965) <em>Polygala </em>L. <em>In</em>: Davis, P.H. (Ed.) <em>Flora of Turkey and the East Aegean Islands </em>1. Edinburgh University Press, Edinburgh, pp. 533–539.</p>
<p>de Candolle, A.P. (1824) <em>Prodromus systematics</em>, 1<em>. </em>Naturalis Regni vegetabilis, 326 pp.</p>
<p>Dönmez, A.A., Uğurlu Aydɪn, Z. & Işik, S. (2015) <em>Polygala turcica </em>(Polygalaceae), a new species from E Turkey, and a new identification key to Turkish <em>Polygala</em>. <em>Willdenowia </em>45 (3): 429–434. https://doi.org/10.3372/wi.45.45309</p>
<p>Erdtman, G. (1952) <em>Pollen morphology and plant taxonomy. Angiosperms</em>. Chronica Botanica. Waltham, Massachusetts.</p>
<p>Erdtman, G. (1986) <em>Pollen morphology and plant taxonomy: angiosperms</em> (Vol. 1). Hafner Publishing Company, New York.</p>
<p>Eriksen, B. (1993) Phylogeny of the Polygalaceae and its taxonomic implications. <em>Plant Systematics and Evolution </em>186: 33–55. https://doi.org/10.1007/BF00937712</p>
<p>Eriksen, B. & Persson, C. (2007) Polygalaceae. In <em>Flowering Plants</em>–<em>Eudicots</em>. Springer, Berlin, Heidelberg, pp. 345–363. https://doi.org/10.1007/978-3-540-32219-1_41</p>
<p>Eriksson, O., Friis, E.M. & Löfgren, P. (2000) Seed size, fruit size, and dispersal systems in angiosperms from the Early Cretaceous to the Late Tertiary. <em>The American Naturalist</em> 156 (1): 47–58. https://doi.org/10.1086/303367</p>
<p>Fagundez, J. & Izco, J. (2011) Seed morphology and anatomy of the Mediterranean pentamerous species of <em>Erica</em> (Ericaceae). <em>Turkish Journal of Botany</em> 35 (6): 643–651. https://doi.org/10.3906/bot-1006-22</p>
<p>Fischer, F.E.L., Meyer, C.A. & Trautvettler, E.R. (1838) <em>Index quartum seminum, quae Hortus Botanicus Imperialis Petropolitanus promutua commutatione offert. Accedunt animadversiones botanicae nonnullae</em>. St. Petersburg, 42 pp.</p>
<p>Forest, F., Chase, M.W., Persson, C., Crane, P.R. & Hawkins, J.A. (2007) The role of biotic and abiotic factors in evolution of ant dispersal in the milkwort family (Polygalaceae). <em>Evolution: International Journal of Organic Evolution</em> 61 (7): 1675–1694. https://doi.org/10.1111/j.1558-5646.2007.00138.x</p>
<p>Fritzsche, J. (1832) <em>Beiträge zur Kenntniss des Pollen</em> (Vol. 1). Stellin and Elbing, Nicolai, Berlin.</p>
<p>Furness, S.H. & Stafford, P.J. (1995) Polygalaceae. The Northwest European Pollen Flora. <em>Review of Palaeobotany and Palynology</em> 88 (1–4): 61–82.https://doi.org/10.1016/0034-6667(95)00019-T</p>
<p>Ghimire, B., Jeong, M.J., Suh, G.U., Heo, K. & Lee, C.H. (2018) Seed morphology and seed coat anatomy of <em>Fraxinus</em>, <em>Ligustrum</em> and <em>Syringa</em> (Oleeae: Oleaceae) and its systematic implications. <em>Nordic Journal of Botany</em> 36 (10): e01866.https://doi.org/10.1111/njb.01866</p>
<p>Heubl, G.R. (1984) Systematische Untersuchungen an mitteleuropaischen <em>Polygala</em> Arten. <em>Mitteilungen der Botanischen Staatssammlung, Munchen</em>.</p>
<p>Isaacs, M.J.H., Weitz, F.M. & Johnson, C.T. (1993) Seed-coat characteristics of selected southern African species of <em>Polygala</em> L.(Polygalaceae). <em>South African Journal of Botany</em> 59 (6): 592–596. https://doi.org/10.1016/S0254-6299(16)30675-5</p>
<p>Jalilian, N. (2005) <em>Flora of Iran, No. 49: Polygalaceae</em>. Agriculture Institute of forests and rangelands press. [In Persian]</p>
<p>Kerrigan, R.A. (2012) A treatment for <em>Polygala </em>of northern Australia. <em>Australian Systematic Botany</em> 25 (2): 83–137. https://doi.org/10.1071/SB08032</p>
<p>Klotzsch, F. & Perers, W.C.H. (1861) Polygalinae. <em>Naturwissenschaften Reise Mossambique</em> 1: 113–117.</p>
<p>Krachai, P., Chantaranothai, P. & Piwpuan, N. (2009) Pollen characteristics of <em>Polygala</em>, <em>Salomonia</em> and <em>Xanthophyllum</em> (Polygalaceae) in Thailand. <em> Tropical Natural History</em> 9 (1): 27–34.</p>
<p>Linnaeus, C. (1753) <em>Species plantarum</em>. L. Salvii, Holmiae [Stockholm], pp. 701–704.</p>
<p>Marques, M.C.M. (2003) Estudo taxonômico do gênero <em>Polygala </em>L. subgênero <em>Ligustrina </em>(Chodat) Paiva (Polygalaceae). PhD Thesis, Museu Nacional do Rio de Janeiro.</p>
<p>Mathew, L. & Teresa, M.V.M. (2010) Seed morphology and its systematic implications in <em>Polygala </em>L.(Polygalaceae). <em>Phytomorphology</em> 60 (3/4): 71–76.</p>
<p>Milby, T.H. (1976) Studies in the floral anatomy of <em>Polygala </em>(Polygalaceae). <em>American Journal of Botany</em> 63 (10): 1319–1326. https://doi.org/10.1002/j.1537-2197.1976.tb13217.x</p>
<p>Mohl, H. (1834) <em>Über den Bau und die Formen der Pollenkôrner. Beiträge zur Anatomie und Physiologie der Gewächse</em>. Bern: Ersters Heft.</p>
<p>Mohl, H. (1835) Sur la structure et lês formes dês graines de pollen. <em>Annales des Sciences Naturelles </em>3: 220–236.</p>
<p>Nauman, C.E. (1981) <em>Polygala grandiflora</em> (Polygalaceae) Walter re-examined. <em>SIDA, Contributions to Botany</em> 1–18.</p>
<p>Paiva, J.A. & Dias, J.D.S. (1989) The pollen grain of <em>Polygala fruticosa </em>Berg. (Polygalaceae). <em>Anales del Jardín Botánico de Madrid </em>47 (2): 377–385.</p>
<p>Paiva, J.A.R. & De Cuba, A.D.C. (1998) Polygalarum africanarum et madagascariensium prodromus atque gerontogaei generis’ <em>Heterosamara</em> ’Kuntze, a genere ’<em>Polygala</em>’ L. segregate et a nobis denuo recepti, synopsis monographica.<em> Cyanus </em>1: 346.</p>
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