title: Towards a comprehensive characterization of durum wheat landraces in Moroccan traditional agrosystems: analysing genetic diversity in the light of geography, farmers' taxonomy and tetraploid wheat domestication history.
abstract: BACKGROUND
  Crop diversity managed by smallholder farmers in traditional agrosystems is the outcome of historical and current processes interacting at various spatial scales, and influenced by factors such as farming practices and environmental pressures. Only recently have studies started to consider the complexity of these processes instead of simply describing diversity for breeding purposes. A first step in that aim is to add multiple references to the collection of genetic data, including the farmers' varietal taxonomy and practices and the historical background of the crop.
  
  
  RESULTS
  On the basis of interview data collected in a previous study, we sampled 166 populations of durum wheat varieties in two traditional Moroccan agrosystems, in the Pre-Rif and Atlas Mountains regions. Using a common garden experiment, we detected a high phenotypic variability on traits indicative of taxonomical position and breeding status, namely spike shape and plant height. Populations often combined modern (short) with traditional-like (tall) statures, and classical durum squared spike shape (5 flowers/spikelet) with flat spike shape (3 flowers/ spikelet) representative of primitive domesticated tetraploid wheat (ssp. dicoccum). By contrast, the genetic diversity assessed using 14 microsatellite markers was relatively limited. When compared to the genetic diversity found in a large collection of tetraploid wheat, it corresponded to free-threshing tetraploid wheat. Within Morocco, the two studied regions differed for both genetic diversity and variety names. Within regions, neither geography nor variety names nor even breeding status constituted strong barriers to gene exchange despite a few significant patterns.
  
  
  CONCLUSIONS
  This first assessment of morphological and genetic diversity allowed pointing out some important factors that may have influenced the structure and evolutionary dynamics of durum wheat in Morocco: the significance of variety names, the occurrence of mixtures within populations, the relative strength of seed exchange between farmers and local adaptation, as well as the fate of modern varieties once they have been introduced. Further, multidisciplinary studies at different spatial scales are needed to better understand these complex agrosystems of invaluable importance for food security.
authors.affiliation: Département de Production, Protection et Biotechnologies Végétales, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202, Rabat-Instituts, Rabat, Morocco. sahriali@gmail.com.
authors.forename: Ali
authors.initials: A
authors.lastname: Sahri
authors.affiliation: Département de Production, Protection et Biotechnologies Végétales, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202, Rabat-Instituts, Rabat, Morocco. lamyae.chentoufi@gmail.com.
authors.forename: Lamyae
authors.initials: L
authors.lastname: Chentoufi
authors.affiliation: Département de Production, Protection et Biotechnologies Végétales, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202, Rabat-Instituts, Rabat, Morocco. mustaphaarbaoui@hotmail.com.
authors.forename: Mustapha
authors.initials: M
authors.lastname: Arbaoui
authors.affiliation: INRA, UMR 1334, Amélioration Génétique et Adaptation des Plantes méditerranéennes et tropicales (AGAP), 2 place Pierre Viala, F-34060, Montpellier Cedex 1, France. Morgane.ardisson@supagro.inra.fr.
authors.forename: Morgane
authors.initials: M
authors.lastname: Ardisson
authors.affiliation: Département de Production, Protection et Biotechnologies Végétales, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202, Rabat-Instituts, Rabat, Morocco. l.belqadi@gmail.com.
authors.forename: Loubna
authors.initials: L
authors.lastname: Belqadi
authors.affiliation: Département de Production, Protection et Biotechnologies Végétales, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202, Rabat-Instituts, Rabat, Morocco. ahmed.birouk@gmail.com.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Birouk
authors.affiliation: INRA, UMR 1334, Amélioration Génétique et Adaptation des Plantes méditerranéennes et tropicales (AGAP), 2 place Pierre Viala, F-34060, Montpellier Cedex 1, France. Pierre.Roumet@supagro.inra.fr.
authors.forename: Pierre
authors.initials: P
authors.lastname: Roumet
authors.affiliation: INRA, UMR 1334, Amélioration Génétique et Adaptation des Plantes méditerranéennes et tropicales (AGAP), 2 place Pierre Viala, F-34060, Montpellier Cedex 1, France. Marie-Helene.Muller@supagro.inra.fr.
authors.forename: Marie-Hélène
authors.initials: MH
authors.lastname: Muller
mesh_terms: D000383:Agriculture; D001947:Breeding; D035264:Flowers / Q000235:genetics; D014644:Genetic Variation; D008027:Light; D018895:Microsatellite Repeats; D009018:Morocco; D010641:Phenotype; D012639:Seeds / Q000235:genetics; D057891:Tetraploidy; D014908:Triticum / Q000145:classification / Q000235:genetics*