Genome size, chromosome number, and rDNA organisation in Algerian populations ofArtemisia herba-alba(Asteraceae), a basic plant for animal feeding facing overgrazing erosion

Anales del Jardín Botánico de Madrid

Joan Vallès³  Teresa Garnatje²  Youcef Bougoutaia⁵  Sònia Garcia⁴  Meriem Kaid-Harche¹ 

[1] Laboratoire des Productions Valorisations Végétales et Microbiennes, Département de Biotechnologie, Faculté des Sciences de la Nature et de la Vie, Université des Sciences et de la Technologie d’Oran Mohamed Boudiaf;Institut Botànic de Barcelona (IBB-CSIC-ICUB);Laboratori de Botànica. Unitat Associada CSIC, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona;Laboratori de Botànica. Unitat Associada CSIC, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona - Institut Botànic de Barcelona (IBB-CSIC-ICUB);Laboratoire des Productions Valorisations Végétales et Microbiennes, Département de Biotechnologie, Faculté des Sciences de la Nature et de la Vie, Université des Sciences et de la Technologie d’Oran Mohamed Boudiaf - Université de Djelfa

关键词: Anthemideae;    Artemisia herba-alba;    chromosome number;    cytogenetics;    fluorescent in situ hybridisation;    genome organisation;    genome size;    karyology;    polyploidy;    rDNA loci;   

DOI  :  

学科分类：植物学

来源: Jardin Botanico de Madrid. Anales

【 摘 要 】

Artemisia herba-albais a largely-distributed and often landscape-dominating taxon in arid areas of the Mediterranean and Irano-Turanian regions. In Algeria, in 2010 its communities covered 10% of the steppe territory, but its populations have been subjected to overgrazing. A karyological study based on 22 populations together with a cytogenetic characterisation of this species has been performed for the first time in Algerian materials, through genome size and chromosome number determination. Fluorescence in situ hybridisation (FISH) was also used to assess the rDNA loci number and distribution in the two ploidy levels detected. The studied accessions are diploid ( 2n=2x= 18 chromosomes, 6 populations) or tetraploid ( 2n= 4x = 36 chromosomes, 15 populations). One population, occupying a more or less central geographic position among the studied area, presented both cytotypes. Genome size reflects well the two ploidy levels, with no evidence of downsizing with polyploidy. The karyotypes are rather symmetric (2A Stebbins�? class). FISH analyses detected four signals (2 loci) in diploid and eight signals (4 loci) in tetraploid cytotypes for both ribosomal DNA genes, which present an L-type (linked) organisation, i.e. with loci from both rDNA genes colocalised. The presence of two ploidy levels suggest a genomic dynamism and even a possible differentiation underlying the morphological uniformity and despite the dramatic decrease experienced by this plant in Algeria in terms of surface coverage.

【 授权许可】

Unknown