Revue internationale d'écologie méditerranéenne International ...

Phylogenetic relationships and infrageneric classification of Astragalus tragacantha L. (Fabaceae), inferred from nuclear ribosomal
DNA Internal transcribed spacers data (nrDNA ITS)
Figure 2 – Strict consensus of 8 most parsimonious trees based on a matrix of 18 nrDNA ITS sequences. Numbers are bootstrap
values for replicate analyses (values < 50% not indicated). Clades are identified by letters based on previous molecular
studies (Wojciechowski et al., 1999; Kazempour Osaloo et al., 2005). Taxonomy, GenBank accession numbers and sample
origin are mentioned in appendix 2. Species information are based on different flora (Tutin et al. 1968; Podlech 1999;
Davis 1970), and on the two following websites: http://loco.biosci.arizona.edu/astragalus/astragalus_home. htm. Website
for Astragalus (Hu J-M., Sanderson M. & Wojciechowski M.), http://www.ildis.org/International Legume Database &
Information Service website.
bound search (gaps, constant and uninformative
characters excluded) generated 8 equally
most parsimonious trees of 58 steps (CI
= 0.914; RI = 0.943). The resulting strict consensus
tree shows that Astragalus tragacantha
sequences gather in a monophyletic clade,
closely related to Astragalus fragrans and
Astragalus odoratus, two herbaceous perennial
species without spines, occurring around
the Southern border between Europe and Asia
(Anatolia, Caucasia) (Table 1).
ecologia mediterranea – Vol. 36 (1) – 2010
Other astragals of clade C occur in different
areas of North Hemisphere (Europe, Asia and
America). If we consider the node gathering
A. depressus with annual species as not robust
(bootstrap value < 50%), only chromosome
number and annual/perennial life cycle seem
to be clearly discriminant characters (Figure
2). All these astragals possess bifurcate
hairs, excepted Astragalus boeticus. Ecology,
altitude and pod length do not show a marked
cutting in phylogeny.
Table 1 – Values of P distances between Astragalus tragacantha (A. trag.) and their nearest relatives,
calculated using pairwise deletion option.
A. trag. A. trag. A. trag. A. trag. A. trag. A. trag. A. fragrans A. odoratus
Ga1 Ga2 Ga3 Ga4 Co1 Co2
A. trag. Ga1 -
A. trag. Ga2 0,008 -
A. trag. Ga3 0,003 0,006 -
A. trag. Ga4 0,008 0,011 0.006 -
A. trag. Co1 0,008 0,011 0.006 0.011 -
A. trag. Co2 0,008 0,011 0.006 0.011 0.000 -
A. fragrans 0,017 0,019 0.014 0.019 0.008 0,008 -
A. odoratus 0,017 0,019 0.014 0.019 0.008 0.008 0.006 -
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