title: Geographic isolation affects inter- and intra-specific seed variability in the Astragalus tragacantha complex, as assessed by morpho-colorimetric analysis.
abstract: The effect of geographical isolation on the inter- and intra-specific seed variability of the Astragalus tragacantha complex was investigated by using a computer-aided imaging system. In particular, seed morphometric and colorimetric features of Astragalus balearicus, A. tegulensis, A. terraccianoi, A. thermensis and A. tragacantha were measured and the data were used to discriminate among regions of provenance, taxa and populations. Discriminant analysis of the data supports the accepted taxonomy of the group and the hypothesis that interspecific differentiation resulted from geographical isolation. The results also showed a positive correlation between the wideness of species' distribution and the levels of seed intra-specific variability.
authors.affiliation: Centro Conservazione Biodiversità (CCB), Dipartimento di Scienze della Vita e dell'Ambiente (DISVA), Università degli Studi di Cagliari, V.le S. Ignazio da Laconi 11-13, 09123 Cagliari, Italy. oscar.grillo.mail@gmail.com
authors.forename: Oscar
authors.initials: O
authors.lastname: Grillo
authors.forename: Efisio
authors.initials: E
authors.lastname: Mattana
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Fenu
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Venora
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Bacchetta
mesh_terms: D027883:Astragalus Plant / Q000033:anatomy & histology* / Q000145:classification; D003116:Color; D003124:Colorimetry; D003627:Data Interpretation, Statistical; D016002:Discriminant Analysis; D005843:Geography; D007091:Image Processing, Computer-Assisted; D019083:Mediterranean Region; D015203:Reproducibility of Results; D012639:Seeds / Q000033:anatomy & histology* / Q000145:classification; D013045:Species Specificity