Towards a global perspective for Salvia L.: Phylogeny, diversification and floral evolution.

Salvia is the most species-rich genus in Lamiaceae, encompassing approximately 1000 species distributed all over the world. We sought a new evolutionary perspective for Salvia by employing macroevolutionary analyses to address the tempo and mode of diversification. To study the association of floral traits with speciation and extinction, we modelled and explored the evolution of corolla length and the lever-mechanism pollination system across our Salvia phylogeny. We reconstructed a multigene phylogeny for 366 species of Salvia in the broad sense including all major recognized lineages and 50 species from Iran, a region previously overlooked in studies of the genus. Our comprehensive sampling of Iranian species of Salvia provides higher phylogenetic resolution for southwestern Asian species than obtained in previous studies. Our phylogenetic data in combination with divergence time estimates were used to examine the evolution of corolla length, woody versus herbaceous habit, and presence versus absence of a lever mechanism. We investigated the timing and dependence of Salvia diversification related to corolla length evolution through a disparity test and BAMM analysis. A HiSSE model was used to evaluate the dependency of diversification on the lever-mechanism pollination system in Salvia. A medium corolla length (15-18 mm) was reconstructed as the ancestral state for Salvia with multiple shifts to shorter and longer corollas. Macroevolutionary model analyses indicate that corolla length disparity is high throughout Salvia evolution, significantly different from expectations under a Brownian motion model during the last 28 million years of evolution. Our analyses show evidence of a higher diversification rate of corolla length for some Andean species of Salvia compared to other members of the genus. Based on our tests of diversification models, we reject the hypothesis of a direct effect of the lever mechanism on Salvia diversification. Therefore, we suggest caution in considering the lever-mechanism pollination system as one of the main drivers of speciation in Salvia.

Analysis of the genetic diversity and affinities of different Iranian Satureja species based on SAMPL markers.

The different species of the genus Satureja are known as "Marze Kohi" in Iran. Herbal drugs of these plants have long been used in traditional medicine, and some species are currently used in food and pharmaceutical industries. In the present work, the genetic diversity and affinities of several Satureja species were studied based on Selectively Amplified Microsatellite Polymorphic Loci (SAMPL) using five primer combinations. A total of 515 polymorphic DNA fragments were amplified, with a mean of 103 bands per assay. Among the species the maximum distance was observed between S. hortensis and S. Isophylla, while the maximum degree of similarity was obtained between S. rechingeri and S. khuzistanica. Cluster analysis was performed for all SAMPL data using the neighbor-joining method. All species for which multiple accessions were sampled were monophyletic with maximum bootstrap support. The investigated species were clustered in three main groups. In general, the relationships among Satureja species revealed by the cluster analysis were somewhat congruent with their geographical distributions.