title: Unlocking the Karyological and Cytogenetic Diversity of Iris from Lebanon: Oncocyclus Section Shows a Distinctive Profile and Relative Stasis during Its Continental Radiation.
abstract: Despite being an important target of conservation concern and horticultural interest, Lebanese irises yet have a confusing taxonomic history and species' delimitation is often considered problematic, more especially among royal irises (Iris section Oncocyclus). Indeed, these irises of exceptionally large and spectacular flowers have radiated across Caucasus and eastern Mediterranean giving rise to a number of strict endemic taxa, many of them being considered under threat. Whilst efforts have mostly focused on clarifying the evolutionary relationships in the group based on morphological and molecular data, karyological and cytogenetic characters have been comparatively overlooked. In this study, we established for the first time the physical mapping of 35S rDNA loci and heterochromatin, and obtained karyo-morphological data for ten Lebanese Iris species belonging to four sections (Iris, Limniris, Oncocyclus and Scorpiris). Our results evidenced distinctive genomic profiles for each one of the sections, where Oncocyclus irises, while having the lowest chromosome numbers, exhibit both the highest number of 35S loci and CMA3+ sites. The continental radiation of royal irises has been accompanied by a relative karyological and cytogenetic stasis, even though some changes were observed regarding karyotype formula and asymmetry indexes. In addition to that, our results enabled taxonomic differentiation between I. germanica and I. mesopotamica-two taxa currently considered as synonyms-and highlighted the need for further studies on populations of I. persica and I. wallasiae in the Eastern Mediterranean Region.
authors.affiliation: Faculté des Sciences, Département Sciences de la Vie et de la Terre, Laboratoire Caractérisation Génomique des Plantes, Campus Sciences et Technologies, Université Saint-Joseph, Mar Roukos Mkalles, Lebanon.|Ecologie, Systématique, Evolution, UMR 8079 Univ. Paris-Sud, AgroParisTech, Université Paris-Saclay, Bat. 360, 91405 Orsay, France.
authors.forename: Nour
authors.initials: N
authors.lastname: Abdel Samad
authors.affiliation: Faculté des Sciences, Département Sciences de la Vie et de la Terre, Laboratoire Caractérisation Génomique des Plantes, Campus Sciences et Technologies, Université Saint-Joseph, Mar Roukos Mkalles, Lebanon.
authors.forename: Magda
authors.initials: M
authors.lastname: Bou Dagher-Kharrat
authors.affiliation: Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, United Kingdom.
authors.forename: Oriane
authors.initials: O
authors.lastname: Hidalgo
authors.affiliation: Faculté des Sciences, Département Sciences de la Vie et de la Terre, Laboratoire Caractérisation Génomique des Plantes, Campus Sciences et Technologies, Université Saint-Joseph, Mar Roukos Mkalles, Lebanon.
authors.forename: Rana
authors.initials: R
authors.lastname: El Zein
authors.affiliation: Faculté des Sciences, Département Sciences de la Vie et de la Terre, Laboratoire Caractérisation Génomique des Plantes, Campus Sciences et Technologies, Université Saint-Joseph, Mar Roukos Mkalles, Lebanon.
authors.forename: Bouchra
authors.initials: B
authors.lastname: Douaihy
authors.affiliation: Ecologie, Systématique, Evolution, UMR 8079 Univ. Paris-Sud, AgroParisTech, Université Paris-Saclay, Bat. 360, 91405 Orsay, France.
authors.forename: Sonja
authors.initials: S
authors.lastname: Siljak-Yakovlev
mesh_terms: D032461:Chromosomes, Plant / Q000235:genetics; D003582:Cytogenetics; D035264:Flowers / Q000145:classification / Q000235:genetics; D014644:Genetic Variation; D006570:Heterochromatin / Q000235:genetics; D031323:Iris Plant / Q000166:cytology / Q000235:genetics*; D059785:Karyotype; D007861:Lebanon; D010802:Phylogeny; D012270:Ribosomes / Q000235:genetics
chemical_list: D006570:Heterochromatin