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The genus Dyckia (Bromeliaceae) comprises more than 150 terrestrial or epilithic species with a strongly xeromorphic habit. Most of its members belong to the azonal rock vegetation of Neotropical savannas and forests of Brazil and adjacent countries. Dyckia is relatively species-rich compared with its closest relatives Encholirium (27 species) and Deuterocohnia (17 species). Here, we present the first molecular phylogenetic analysis of Dyckia using DNA sequence data from six plastid loci ( matK gene, rps16 intron, petD intron, rpl32- trnL, rps16- trnK and trnD- trnT) and a portion of the nuclear gene phyC. A total of 124 accessions were included, corresponding to 79 taxa from six genera. Phylogenetic trees were generated using parsimony, likelihood and Bayesian methods. DNA sequence variation among Dyckia species turned out to be extremely low, and phylogenies were poorly resolved. The monophyly of Dyckia is supported, whereas evidence is provided that Encholirium is paraphyletic. Based on a dated plastid DNA tree, Dyckia experienced a recent radiation starting around 2.9 million years ago. Four major clades could be identified that roughly correspond to the geographic origin of the samples. A parsimony network based on plastid DNA haplotypes shows a star-like pattern, indicating recent range expansions. Our data are compatible with a scenario where Dyckia and Encholirium diverged in northeastern Brazil, whereas one lineage of Dyckia dispersed to southern Brazil from where a rapid colonization of suitable habitats was initiated. We discuss our results in relation to species delimitation in Dyckia. [ABSTRACT FROM AUTHOR]

Almonds and peaches are among the most economically important fruit crops in subtropical and temperate regions. Questions regarding the origin and domestication of the crop species, interspecific relationships, and evolutionary patterns of fruits have remained unanswered due to the lack of phylogenetic data of Prunus subgenus Amygdalus, in which both almond and peach are classified. Twenty-two species of subg. Amygdalus were included in phylogenetic analyses of plastid ndhF- rpl32, rpL16, trnH- psbA, trnL- trnF, trnQ- 5′ rps16, and trnS- trnG and nuclear s6pdh genes to investigate the circumscription of subg. Amygdalus, phylogenetic relationships among the species, and implication for mesocarp and endocarp evolution. Prunus subg. Amygdalus is best circumscribed to include both almonds and peaches, comprising two sections, Amygdalus and Persica. Species traditionally placed close to almonds, such as P. tenella, P. petunnikowii, P. triloba, and P. pedunculata, should be excluded from subg. Amygdalus. Characteristics used to diagnose subg. Amygdalus, such as dry, splitting mesocarp and the ornamentation of endocarp evolved multiple times in Prunus; thus classification based solely on these morphological characters produces a taxonomic scheme that might not represent common ancestry. A dry, splitting mesocarp is likely to be ancestral for the common ancestor of subg. Amygdalus, and the fleshy, non-splitting mesocarp found in peaches was derived from the dry, splitting mesocarp, presumably by domestication and selection for a fleshy fruit in China. Very low genetic divergence among cultivated almond and its close relatives might be associated with gene flow and/or rapid speciation within the group. [ABSTRACT FROM AUTHOR]

Dianthus polylepis complex consists of two already known endemic species, Dianthus polylepis and D. binaludensis, in Khorassan-Kopetdagh floristic province. The taxonomic position of these species has long been debated. The aim of the present study is to shed light on the evolutionary relationships of the members of the complex using morphological and molecular data. In morphological study, firstly, 56 vegetative and floral characters were measured on 33 specimens of the both species. Multivariate analyses were performed on 25 (out of 56) significantly discriminating morphological traits. In molecular study, we sequenced alleles obtained from a region between 2nd and 6th exons of the gene coding for the enzyme dihydroflavonol 4-reductase copy1 (DFR1). Morphological results show that most of a priori identified accessions were not grouped in a posteriori classification. It is difficult to discriminate D. polylepis from D. binaludensis in morphological continuum among the accessions. Results obtained from the molecular data indicated no monophyly for the members of the D. polylepis complex. Consistency between the morphological and molecular results shows that D. polylepis and D. binaludensis were not morphologically and molecularly well differentiated. Therefore, we propose a new combination as D. polylepis subsp. binaludensis. [ABSTRACT FROM AUTHOR]