Phylogeny and biogeography of Alyssum (Brassicaceae) based on nuclear ribosomal ITS DNA sequences

Abstract

The genus Alyssum consists of about 195 species native to Europe, Asia and northern Africa. All species were assigned to six sections. Previous molecular phylogeny studies indicate that Alyssum is polyphyletic. However, the divergence time and dispersal of the genus are not well studied. In this study, the phylogenetic relationships within the genus Alyssum were studied with nrDNA ITS sequences obtained from five sections. The divergence time was estimated by fossil calibration and the biogeography was examined by spread analysis. The phylogeny indicated two main lineages: lineage 1 includes the section of Alyssum, Gamosepalum and Psilonema; lineage 2 includes the section of Odontarrhena, Meniocus and Clypeola. The phylogenetic relationship was not congruent with the previous sectional classifications. The age of Alyssum was dated to the upper Miocene. Molecular data suggested the diversification of Alyssum in Mediterranean areas and wide-ranging distribution such as North Africa, eastward into Central Asia and immigration into North America. Climatic aridification and arid/semiarid areas established in the Pliocene/Pleistocene could have provided favourable conditions for the migration and diversification of Alyssum.

Is hybridization driving the evolution of climatic niche in Alyssum montanum

“…is a monophyletic polyploid complex (Rešetnik et al, 2013) within the Brassicaceae, including over 30 species and subspecies with variable levels of ploidy. This group has diversified over the last 2 million years (Li et al, 2014) and comprises perennial species distributed in Europe, western Asia, and northern Africa, with maximal species diversity in submediterranean areas (Jalas et al, 1996; Španiel et al, 2011a, b; Zozomová‐Lihová et al, 2014; and references therein). Here, we extensively reviewed the recent literature addressing the taxonomy and molecular genetics of Alyssum montanum s.l.…”

Variation of Phenolic and Pigment Composition Depending on Soil Type in Three Serpentinovag Plant Species

“…The genus Alyssum L. consists of 230 species that are native to Europe, Asia and Northern Africa. Species richness and diversity are confined to the Mediterranean and Turkey, and only a few species are distributed in North Africa, Central Asia, Siberia and North America (Li et al, 2014). Alyssum sibiricum Willd.…”

Alyssum desertorum Stapf (Brassicaceae), new for the Italian flora

“…2008, Rešetnik et al 2013, Li et al 2014). This genus was divided into six sections by Dudley (1964): Alyssum sect.…”

“…Tetradenia were transferred into the genus Hormathophylla & T. R. Dudley (Kupfer 1974). However, recent molecular phylogeny studies indicate that Alyssum is polyphyletic and that the current taxonomic circumscription of the genus needs to be revised (Rešetnik et al 2013, Li et al 2014.…”