title: Karyotype analysis and visualization of 45S rRNA genes using fluorescence in situ hybridization in aroids (Araceae).
abstract: Karyotype analysis and FISH mapping using 45S rDNA sequences on 6 economically important plant species Anthuriumandraeanum Linden ex André, 1877, Monsteradeliciosa Liebmann, 1849, Philodendronscandens Koch & Sello, 1853, Spathiphyllumwallisii Regel, 1877, Syngoniumauritum (Linnaeus, 1759) Schott, 1829 and Zantedeschiaelliottiana (Knight, 1890) Engler, 1915 within the monocotyledonous family Araceae (aroids) were performed. Chromosome numbers varied between 2n=2x=24 and 2n=2x=60 and the chromosome length varied between 15.77 µm and 1.87 µm. No correlation between chromosome numbers and genome sizes was observed for the studied genera. The chromosome formulas contained only metacentric and submetacentric chromosomes, except for Philodendronscandens in which also telocentric and subtelocentric chromosomes were observed. The highest degree of compaction was calculated for Spathiphyllumwallisii (66.49Mbp/µm). B-chromosome-like structures were observed in Anthuriumandraeanum. Their measured size was 1.87 times smaller than the length of the shortest chromosome. After FISH experiments, two 45S rDNA sites were observed in 5 genera. Only in Zantedeschiaelliottiana, 4 sites were seen. Our results showed clear cytogenetic differences among genera within Araceae, and are the first molecular cytogenetics report for these genera. These chromosome data and molecular cytogenetic information are useful in aroid breeding programmes, systematics and evolutionary studies.
authors.affiliation: Institute for Agricultural and Fisheries Research (ILVO), Plant Sciences Unit, Applied Genetics and Breeding, Caritasstraat 21, 9090 Melle, Belgium ; Department of Plant Production, Faculty of Bioscience Engineering, Ghent University (UGent), Coupure links 653, 9000 Ghent, Belgium ; Center of Molecular Biotechnology, Department of Genetics and Biotechnology, Russian State Agrarian University-Timiryazev Agricultural Academy (TIMACAD), 49, Timiryazevskaya str., 127550 Moscow, Russia.
authors.forename: Prabhu Shankar
authors.initials: PS
authors.lastname: Lakshmanan
authors.affiliation: Institute for Agricultural and Fisheries Research (ILVO), Plant Sciences Unit, Applied Genetics and Breeding, Caritasstraat 21, 9090 Melle, Belgium.
authors.forename: Katrijn
authors.initials: K
authors.lastname: Van Laere
authors.affiliation: Institute for Agricultural and Fisheries Research (ILVO), Plant Sciences Unit, Applied Genetics and Breeding, Caritasstraat 21, 9090 Melle, Belgium.
authors.forename: Tom
authors.initials: T
authors.lastname: Eeckhaut
authors.affiliation: Institute for Agricultural and Fisheries Research (ILVO), Plant Sciences Unit, Applied Genetics and Breeding, Caritasstraat 21, 9090 Melle, Belgium.
authors.forename: Johan
authors.initials: J
authors.lastname: Van Huylenbroeck
authors.affiliation: Institute for Agricultural and Fisheries Research (ILVO), Plant Sciences Unit, Applied Genetics and Breeding, Caritasstraat 21, 9090 Melle, Belgium ; Department of Plant Production, Faculty of Bioscience Engineering, Ghent University (UGent), Coupure links 653, 9000 Ghent, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Van Bockstaele
authors.affiliation: Center of Molecular Biotechnology, Department of Genetics and Biotechnology, Russian State Agrarian University-Timiryazev Agricultural Academy (TIMACAD), 49, Timiryazevskaya str., 127550 Moscow, Russia.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Khrustaleva
keywords: Araceae; B-chromosomes; FISH; chromosome formula; cytogenetics; genome size