32 research outputs found
Los marcadores microsatélite revelan la reestructuración genética de Medicago sinskiae (Fabaceae) en el oeste y el sudoeste de Irán
Medicago sinskiae appears to be a very rare species in the Iranian flora with only a few records in the last three decades. Eight populations (62 individuals) of M. sinskiae, one population of M. rigidula (seven individuals), and one population of M. constricta (five individuals) from western and southwestern Iran were analyzed for microsatellite data based on newly designed SSR primers using NGS technology. The PCoA, Clustering and Structure analyses showed no geographical pattern of genetically designated clusters. Our results showed that M. sinskiae is mainly an inbreeder. It is assumed that high levels of gene flow (Nm) and generation of genetically homogenous populations seem to be more affected by fast dispersal and not localized gene flow. Extensive collections recently made from the western and southwestern Iran showed that its presence is increasing. Finally, our results indicate that the species is segregated from its very close relatives M. rigidula and M. constricta in Iran.Medicago sinskiae es considerada una especie rara en la flora iraní con únicamente unas pocas citas en las tres últimas décadas. Se han muestreado ocho poblaciones (62 individuos) de M. sinskiae, una población de M. rigidula (siete individuos) y una población de M. constricta (cinco individuos) en el oeste y el suroeste de Irán que han sido analizadas con marcadores microsatélite. Se han utilizado nuevos primers obtenidos con tecnología NGS. Los análisis de PCoA, Clustering y Structure no muestran un patrón geográfico para los clústeres genéticos. Los resultados muestran que M. sinskiae es principalmente una especie autógama. Se asume que los altos niveles de flujo genético (Nm) y la homogeneidad genética poblacional están afectados por una rápida dispersión y un flujo genético no localizado. Recolecciones extensivas realizadas recientemente en el oeste y el suroeste de Iran muestran que el rango de distribución esta especie se está incrementando. Finalmente, nuestros resultados indican que M. sinskiae está diferenciada de las especies M. rigidula y M. constricta en Irán
Genetic diversity and morphological variability of Iranian Silene aucheriana populations inferred from nrDNA ITS sequences and morphological analysis
We conducted a comprehensive study on the diversity of Silene aucheriana Boiss. populations by analyzing both morphological data and nrDNA ITS sequences. Maximum parsimony and Bayesian methods on representative material from 15 populations throughout Iran demonstrated that they did not form a monophyletic group. Strong positive correlation occurred between epipetalous filaments length to claw (EFLC), basal leaf length (BLL), basal leaf width (BLW), and plant height (PLH) with elevation. While negative correlation achieved between anthophore length (AnL) with the average air temperature and rainfall. Canonical Correspondence Analysis (CCA) showed that most morphological traits were more correlated to elevation than to average rainfall and temperature. Multivariate analysis of morphological traits with ITS analysis displayed a slight divergence between two types of regions based on their elevation
Application and limitation of molecular data and essential oil content in identification of Leutea elbursensis Mozaff in northern Iran
In this paper, the internal transcribed spacer (ITS) sequences, genetic structure and the chemical composition of essential oils of four populations belonging to Leutea elbursensis and Leutea petiolaris, two species endemic to northern Iran, are analyzed. Phylogenetic analysis based on the ITS data showed that all accessions of L. elbursensis
formed a monophyletic clade, and L. elbursensis was a sister to the rest of Leutea species. Results of amplified fragment length polymorphism (AFLP) analysis performed on the total genome showed that all individuals presented in the study belonged to two different genetic clusters. The individuals belong to L. petiolaris had a different genetic structure and yielded no traceable amount of essential oils. The essential oil obtained from the ripe fruits of L. elbursensis yielded
0.5–0.6% of volatile essential oils. In total, 15–29 volatile natural components were identified on the basis of their mass spectra characteristics and retention indices, in which α-pinene (33.18–43.22%), β-pinene (32.4–40.9%) were the major constituents. Our results indicate that L. elbursensis is a distinct species, segregated from the other species based on morphology, ITS data and AFLP profile. In addition, despite the relatively uniform genetic structure of L. elbursensis, the chemical composition of essential oil could be highly affected by different factors
Generic boundaries in subtribe Saussureinae (Compositae: Cardueae): Insights from Hyb-Seq data
The subtribe Saussureinae is a highly speciose group with more than 600 species distributed in the Northern Hemisphere and is particularly species-rich at the high mountains of central and eastern Asia. Saussurea and Jurinea are the two main genera described within the subtribe. However, up to 15 satellite genera are recognized in some recent taxonomic treatments with an analytical viewpoint. For the first time, we carried out a complete sampling to clarify generic boundaries based on a well-resolved phylogeny of Saussureinae. We employed a Hyb-Seq technique that targets 1061 nuclear conserved ortholog loci designed for Compositae. After a filtering of potential paralogs, 588 loci were retained to infer phylogenetic trees under concatenation and coalescence approaches. High branch support resolution was recovered at the generic level, but a non-monophyletic pattern was detected for most of the genera as they are currently circumscribed. Accordingly, we propose a new generic delimitation based on the three main clades recovered in the backbone tree, which are also in agreement with morphological evidence: Dolomiaea, Saussurea, and Jurinea. Following this classification into three genera, 18 new combinations are proposed. This new genus delineation will be used as a basis for future evolutionary studies in the Saussureinae.Financial support from the Ministerio de Ciencia e Innovación (Project CGL2015-66703-P MINECO/FEDER, UE and Ph.D. grant to Sonia Herrando-Moraira) and the Catalan government (“Ajuts a grups consolidats” 2017-SGR1116) is also greatly acknowledged. This study has been performed under the Ph.D. program “Plant Biology and Biotechnology” of the Autonomous University of Barcelona (UAB)INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
TAXONOMIC IMPLICATIONS
NOTE ADDED IN PROOF
AUTHOR CONTRIBUTIONS
ACKNOWLEDGMENT
African Mountain Thistles: Three New Genera in the Carduus-Cirsium Group
The floras on the highest mountains in tropical eastern Africa are among the most unique floras in the world. Despite the exceptionally high concentration of endemic species, these floras remain understudied from an evolutionary point of view. In this study, we focus on the Carduus-Cirsium group (subtribe Carduinae) to unravel the evolutionary relationships of the species endemic to the tropical Afromontane and Afroalpine floras, aiming to improve the systematics of the group. We applied the Hyb-Seq approach using the Compositae1061 probe set on 190 samples (159 species), encompassing representatives of all genera of Carduinae. We used two recently developed pipelines that enabled the processing of raw sequence reads, identification of paralogous sequences and segregation into orthologous alignments. After the implementation of a missing data filter, we retained sequences from 986 nuclear loci and 177 plastid regions. Phylogenomic analyses were conducted using both concatenated and summary-coalescence methods. The resulting phylogenies were highly resolved and revealed three distinct evolutionary lineages consisting of the African species traditionally referred to as Carduus and Cirsium. Consequently, we propose the three new genera Afrocarduus, Afrocirsium and Nuriaea; the latter did notably not belong to the Carduus-Cirsium group. We detected some incongruences between the phylogenies based on concatenation vs. coalescence and on nuclear vs. plastid datasets, likely attributable to incomplete lineage sorting and/or hybridization
Phylogenomics and morphological evolution of the mega-diverse genus Artemisia (Asteraceae: Anthemideae): implications for its circumscription and infrageneric taxonomy
Background and Aims
Artemisia is a mega-diverse genus consisting of ~400 species. Despite its medicinal importance and ecological significance, a well-resolved phylogeny for global Artemisia, a natural generic delimitation and infrageneric taxonomy remain missing, owing to the obstructions from limited taxon sampling and insufficient information on DNA markers. Its morphological characters, such as capitulum, life form and leaf, show marked variations and are widely used in its infrageneric taxonomy. However, their evolution within Artemisia is poorly understood. Here, we aimed to reconstruct a well-resolved phylogeny for global Artemisia via a phylogenomic approach, to infer the evolutionary patterns of its key morphological characters and to update its circumscription and infrageneric taxonomy.
Methods
We sampled 228 species (258 samples) of Artemisia and its allies from both fresh and herbarium collections, covering all the subgenera and its main geographical areas, and conducted a phylogenomic analysis based on nuclear single nucleotide polymorphisms (SNPs) obtained from genome skimming data. Based on the phylogenetic framework, we inferred the possible evolutionary patterns of six key morphological characters widely used in its previous taxonomy.
Key Results
The genus Kaschgaria was revealed to be nested in Artemisia with strong support. A well-resolved phylogeny of Artemisia consisting of eight highly supported clades was recovered, two of which were identified for the first time. Most of the previously recognized subgenera were not supported as monophyletic. Evolutionary inferences based on the six morphological characters showed that different states of these characters originated independently more than once.
Conclusions
The circumscription of Artemisia is enlarged to include the genus Kaschgaria. The morphological characters traditionally used for the infrageneric taxonomy of Artemisia do not match the new phylogenetic tree. They experienced a more complex evolutionary history than previously thought. We propose a revised infrageneric taxonomy of the newly circumscribed Artemisia, with eight recognized subgenera to accommodate the new results.This work was supported by the National Natural Science Foundation of China (grant nos. 31870179, 31570204, 31270237 and J1310002), the International Partnership Program (grant no. 151853KYSB20190027), Sino-Africa Joint Research Center (grant no. SAJC201614), Key technology projects of Jiangxi Province's major scientific and technological research and development project (grant no. 20223AAF01007), Survey of Wildlife Resources in Key Areas of Tibet (grant no. ZL202203601) and National Plant Specimen Resource Center (grant no. E0117G1001) of the Chinese Academy of Sciences, Key Project at Central Government Level: The Ability Establishment of Sustainable Use of Valuable Chinese Medicine Resources (grant no. 2060302) and Project of the Central Siberian Botanical Garden of the Siberian Branch of the Russian Academy of Sciences (grant no. AAAA-A21-121011290024-5).Abstract
INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
Conclusions
SUPPLEMENTARY DATA
FUNDING
ACKNOWLEDGEMENTS
CONFLICT OF INTEREST
LITERATURE CITED
Supplementary dat
Impact of the climatic changes in the Pliocene-Pleistocene transition on Irano-Turanian species. The radiation of genus Jurinea (Compositae)
Altres ajuts: acords transformatius de la UABThe Irano-Turanian region is one of the world's richest floristic regions and the centre of diversity for numerous xerophytic plant lineages. However, we still have limited knowledge on the timing of evolution and biogeographic history of its flora, and potential drivers of diversification remain underexplored. To fill this knowledge gap, we focus on the Eurasian genus Jurinea (ca. 200 species), one of the largest plant radiations that diversified in the region. We applied a macroevolutionary integrative approach to explicitly test diversification hypotheses and investigate the relative roles of geography vs. ecology and niche conservatism vs. niche lability in speciation processes. To do so, we gathered a sample comprising 77% of total genus richness and obtained data about (1) its phylogenetic history, recovering 502 nuclear loci sequences; (2) growth forms; (3) ecological niche, compiling data of 21 variables for more than 2500 occurrences; and (4) paleoclimatic conditions, to estimate climatic stability. Our results revealed that climate was a key factor in the evolutionary dynamics of Jurinea. The main diversification and biogeographic events that occurred during past climate changes, which led to colder and drier conditions, are the following: (1) the origin of the genus (10.7 Ma); (2) long-distance dispersals from the Iranian Plateau to adjacent regions (∼7-4 Ma); and (3) the diversification shift during Pliocene-Pleistocene Transition (ca. 3 Ma), when net diversification rate almost doubled. Our results supported the pre-adaptation hypothesis, i.e., the evolutionary success of Jurinea was linked to the retention of the ancestral niche adapted to aridity. Interestingly, the paleoclimatic analyses revealed that in the Iranian Plateau long-term climatic stability favoured old-lineage persistence, resulting in current high species richness of semi-arid and cold adapted clades; whereas moderate climate oscillations stimulated allopatric diversification in the lineages distributed in the Circumboreal region. In contrast, growth form lability and high niche disparity among closely related species in the Central Asian clade suggest adaptive radiation to mountain habitats. In sum, the radiation of Jurinea is the result of both adaptive and non-adaptive processes influenced by climatic, orogenic and ecological factors
Island-like mountain radiations in Asia: The case study of the genera Saussurea and Jurinea
Trabajo presentado en el XIX International Botanical Congress (IBC 2017), celebrado en Shenzhen (China) del 23 al 29 de julio de 2017Evolutionary radiations represent events in which many species or lineages evolved from a common ancestor in a short period of time. Many plant radiations have been triggered by island-like ecological opportunities following mountain uplift; the mountain ranges with the steepest and widest environmental gradients, such
as the Andes, are home of exceptional regional species pools (and also exceptional endemism rates), mainly derived from evolutionary radiations. The Himalayan-Qinghai-Tibetan Plateau (HQTP) and the adjacent Hengduan Mountains (HM) are considered one of the main biodiversity hotspots of the world thanks to its richness in species and endemics. Both regions show extreme altitudinal ranges compressed in short distances as a consequence of the collision of the Indian and Eurasian plates, and thus constitute
ideal evolutionary scenarios to study diversification processes in mountain regions. We have identified two possible cases of alpine radiations in the Saussurea-Jurinea complex (Compositae-Cardueae),
involving some 550 species in total. Saussurea shows an amazing number of species (more than 300) in the HQTP and Hengduan mountains, although a considerable number of species are also found on the west side of the mountains of Middle Asia (Tian Shan and Pamir-Alay). Jurinea, in contrast, has the highest
number of species (150 sp.) in the Tian Shan and Pamir-Alay. Our general objectives are the following: a) To carry out an extensive sampling of Saussurea and Jurinea, especially centred in the two main radiation areas in the HQTP and Tian Shan mountains; b) To generate well-resolved phylogenies of both genera using a
multi-loci approach through next-generation-sequencing (NGS) analyzed by Bayesian inference and parsimony, and explore coalescent-based species tree estimation with our NGS data set; c) On the basis of the new phylogenies, conduct phylogenetic comparative analyses and multi-model biogeographical inference
to address the following questions: Do the alpine species of both genera in Asian mountains constitute clades with clearly higher rates of diversification than their lowland relatives? How many independent radiations took place in the complex? If several, did they occur at the same period, and are they comparable in terms of
speciation rates? Which factors (intrinsic or extrinsic) shape species radiations, i.e., do the radiations follow a geographical model, an adaptive model, or a mixed model? Our results will be a major contribution to the study of alpine radiations especially in the HQTP, and will open a methodological pathway for the analysis
of very large radiations in other genera.Peer reviewe