Niche divergence and limits to expansion in the high polyploid Dianthus broteri complex

Niche evolution in plant polyploids remains controversial and evidence for alternative patterns has been reported. Using the autopolyploid Dianthus broteri complex (2×, 4×, 6× and 12×) as a model, we aimed to integrate three scenarios – competitive exclusion, recurrent origins of cytotypes and niche filling – into a single framework of polyploid niche evolution. We hypothesized that high polyploids would tend to evolve towards extreme niches when low ploidy cytotypes have nearly filled the niche space. We used several ecoinformatics and phylogenetic comparative analyses to quantify differences in the ecological niche of each cytotype and to evaluate alternative models of niche evolution. Each cytotype in this complex occupied a distinct ecological niche. The distributions were mainly constrained by soil characteristics, temperature and drought stress imposed by the Mediterranean climate. Tetraploids had the highest niche breadth and overlap due to their multiple origins, whereas the higher ploidy cytotypes were found in different, restricted, nonoverlapping niches. Niche evolution analyses suggested a scenario with one niche optimum for each ploidy, including the two independent tetraploid lineages.Our results suggest that the fate of nascent polyploids could not be predicted without accounting for phylogenetic relatedness, recurrent origins or the niche occupied by ancestors.Aridos La Melera S.L. (FIUS project 2234/0724

Epigenetic contribution to successful polyploidizations: variation in global cytosine methylation along an extensive ploidy series in Dianthus broteri (Caryophyllaceae)

Polyploidization is a significant evolutionary force in plants which involves major genomic and genetic changes, frequently regulated by epigenetic factors. We explored whether natural polyploidization in Dianthus broteri complex resulted in substantial changes in global DNA cytosine methylation associated to ploidy. Global cytosine methylation was estimated by high-performance liquid chromatography (HPLC) in 12 monocytotypic populations with different ploidies (2×, 4×, 6×, 12×) broadly distributed within D. broteri distribution range. The effects of ploidy level and local variation on methylation were assessed by generalized linear mixed models (GLMMs). Dianthus broteri exhibited a higher methylation percent (˜33%) than expected by its monoploid genome size and a large variation among study populations (range: 29.3–35.3%). Global methylation tended to increase with ploidy but did not significantly differ across levels due to increased variation within the highest-order polyploidy categories. Methylation varied more among hexaploid and dodecaploid populations, despite such cytotypes showing more restricted geographic location and increased genetic relatedness than diploids and tetraploids. In this study, we demonstrate the usefulness of an HPLC method in providing precise and genome reference-free global measure of DNA cytosine methylation, suitable to advance current knowledge of the roles of this epigenetic mechanism in polyploidization processes.Peer Reviewe

Novedades para el Pre-Rif del Jbel Zalagh (Marruecos)

New taxa from the Pre-Rif of the Jbel Zalagh (Morocco)Palabras clave. Flora, corología, Pre-Rif, Jbel Zalagh, N Marruecos.Key words. Flora, chorology, Pre-Rif, Jbel Zalagh, Norther Morocco

Using rubrics as a self-assessment tool in Botany learning

Las rúbricas o matrices de evaluación son una herramienta educativa para la evaluación del proceso de aprendizaje. En la rúbrica se identifican ciertos criterios en la realización de un trabajo y también se define la gradación de calidad para cada criterio, desde un rendimiento pobre hasta la excelencia. Las rúbricas ayudan a estudiantes y profesores a juzgar la calidad de la tarea realizada por los estudiantes y pueden utilizarse además como herramienta de autoevaluación, mostrándose muy eficaces en algunos estudios previos. La realización de un herbario personal o en grupo ha sido un recurso utilizado para el aprendizaje de la Botánica desde hace años. Los herbarios permiten que el alumno conozca la terminología adecuada de la Taxonomía Botánica, aprenda a preparar, conservar e identificar las plantas con la bibliografía adecuada, y adquiera un conocimiento de visu de la flora local. Asimismo, otras competencias transversales, como la capacidad de trabajo en grupo, pueden ser potenciadas con la realización de dicho herbarios. La evaluación de los herbarios es compleja debido a la diversidad de competencias necesarias para la correcta realización del trabajo. Aquí presentamos una rúbrica desarrollada para que el alumno pueda autoevaluarse según diferentes criterios que se agrupan en tres grandes bloques: (i) Contenido, (ii) Presentación y Documentación, y (iii) Destrezas de trabajo colaborativas (trabajo en grupo). Esta autoevaluación tiene como finalidad la mejora en la presentación de los herbarios y con ello una mejora del rendimiento académico del alumno.A rubric (evaluation matrix) is an educational tool designed to evaluate the learning process. In an evaluation matrix, specific expectations are identified as well as a grade of fulfillment for each criterion, from a poor to an excellent performance. Rubrics make easier the evaluation task carried out by teachers and students, improving its quality, and can be used for self-assessment as its efficiency is proved by previous studies. An individual or collective herbarium is a learning tool that has been used for many years. Herbaria allow that students can familiarize with the Botanical Taxonomy terminology, learn to prepare, preserve and identify plant specimens (with the necessary bibliography), and acquire visual knowledge of local flora. In addition, several transversal competences, like teamwork related skills, are boosted in its construction. The evaluation of a herbarium is complex due to the diversity of necessary competences involved. Here, we bring a rubric to let students self-assess different criteria (grouped in three blocks): (i) Content, (ii) Presentation and Documentation, and (iii) Teamwork skills. The purpose of this self-assessment is to improve the presentation of the herbarium and hence the student's academic performance

AFLPsim: an R package to simulate and detect dominant markers under selection in hybridizing populations

Background In spite of a large diversity of approaches to investigate loci under selection from a population genetic perspective, very few programs have been specifically designed to date to test selection in hybrids using dominant markers. In addition, simulators of dominant markers are very scarce and they do not usually take into account hybridization. Results Here, we present a new, multifunctional, R package for dominant genetic markers, AFLPsim. This package can simulate dominant markers in hybridizing populations and implements genome scan methods for detecting outlier dominant loci in hybrids. In addition, it includes tools for further manipulating the results, plotting them and other tasks. We describe and tabulate the major functions implemented in AFLPsim. In addition, we provide some demonstration of its use and we perform a comparative study with other software. Finally, we conclude by briefly describing the input and output formats. Conclusions The R package AFLPsim application provides several useful tools in the context of hybridization studies. It can simulate dominant markers in hybridizing populations and predict their demographic evolution. In addition, we implement a new genome scan method for detecting outlier dominant loci in hybrids, which shows a rather high sensitivity and is very conservative in comparison with Gagnaire et al.’s, bayescan and introgress. The application is downloadable at http://cran.r-project.org/web/packages/AFLPsim/

Polyploidy promotes divergent evolution across the leaf economics spectrum and plant edaphic niche in the Dianthus broteri complex

The evolution of the leaf economics spectrum (LES) is known to be constrained by genetic relatedness but also promoted at small geographical and phylogenetic scales. In those cases, we hypothesized that polyploidy would play a prominent role as an outstanding source of functional divergence and adaptive potential. We registered leaf-level nutrient, water- and light-economy-related traits from the LES as well as edaphic properties in the four cytotypes of the autopolyploid Dianthus broteri complex (2×, 4×, 6× and 12×). We analysed the effect of ploidy level on the integration of the LES network, checked if concerted evolution occurred between LES and soil niche and tested the influence of phylogeny on the variables. Alternative evolutionary models for both sets of traits were compared. We found higher divergence of polyploids (especially 6× and 12×) compared to diploids in the LES and soil niche, but these traits are not coevolving. 6× and 12× showed opposite ecological strategies regarding resource use and higher uncoupling of the LES network. Early divergence of traits prevailed in both LES and edaphic niche (supported by better fitted evolutionary models with one optimum per cytotype), but post-polyploidization processes played an important role for the photochemical behaviour. Synthesis. Our results indicated shifts in ecological strategies across Dianthus broteri cytotypes and suggested a powerful role of polyploidy in overcoming constraints for the evolution of plant functional traits.PGC2018-098358-B-I00 from the Spanish MICINNÁridos La Melera S.L. (FIUS project 2234/0724

Evaluation of Reference Genes in the Polyploid Complex Dianthus broteri (Caryophyllaceae) Using qPCR

Dianthus broteri is an endemic complex which is considered the largest polyploid series within the Dianthus genus. This polyploid species involves four cytotypes (2×, 4×, 6× and 12×) with spatial and ecological segregation. The study of gene expression in polyploid species must be very rigorous because of the effects of duplications on gene regulation. In these cases, real-time polymer-ase chain reaction (qPCR) is the most appropriate technique for determining the gene expression profile because of its high sensitivity. The relative quantification strategy using qPCR requires genes with stable expression, known as reference genes, for normalization. In this work, we evaluated the stability of 13 candidate genes to be considered reference genes in leaf and petal tissues in Dianthus broteri. Several statistical analyses were used to determine the most stable candidate genes: Bayesian analysis, network analysis based on equivalence tests, geNorm and BestKeeper algorithms. In the leaf tissue, the most stable candidate genes were TIP41, TIF5A, PP2A and SAMDC. Similarly, the most adequate reference genes were H3.1, TIP41, TIF5A and ACT7 in the petal tissue. Therefore, we suggest that the best reference genes to compare different ploidy levels for both tissues in D. broteri are TIP41 and TIF5A.Ministerio de Ciencia e Innovación PGC2018-098358-B-I00Junta de Andalucía US-138123

A novel hot-plate test sensitive to hyperalgesic stimuli and non-opioid analgesics

It is widely accepted that the classical constant-temperature hot-plate test is insensitive to cyclooxygenase inhibitors. In the current study, we developed a variant of the hot-plate test procedure (modified hot-plate (MHP) test) to measure inflammatory nociception in freely moving rats and mice. Following left and right hind paw stimulation with a phlogogen and vehicle, respectively, the animals were placed individually on a hot-plate surface at 51ºC and the withdrawal latency for each paw was determined simultaneously in measurements performed at 15, 60, 180, and 360 min post-challenge. Plantar stimulation of rats (250 and 500 µg/paw) and mice (125-500 µg/paw) with carrageen an led to a rapid hyperalgesic response of the ipsilateral paw that reached a plateau from 15 to 360 min after challenge. Pretreatment with indomethacin (4 mg/kg, ip) inhibited the phenomenon at all the times analyzed. Similarly, plantar stimulation of rats and mice with prostaglandin E2 (0.5 and 1 µg/paw) also resulted in rapid hyperalgesia which was first detected 15 min post-challenge. Finally, we observed that the MHP test was more sensitive than the classical Hargreaves' test, being able to detect about 4- and 10-fold lower doses of prostaglandin E2 and carrageenan, respectively. In conclusion, the MHP test is a simple and sensitive method for detecting peripheral hyperalgesia and analgesia in rats and mice. This test represents a low-cost alternative for the study of inflammatory pain in freely moving animals

El género Baldellia Parl. (Alismataceae) en la Península Ibérica, Baleares y Marruecos.

The genus Baldellia Parl. (Alismataceae) in the Iberian Peninsula, Balearic Island and MoroccoPalabras clave. Baldellia repens, taxones infraespecíficos, W mediterráneo.Key words. Baldellia repens, infraespecific taxa, W mediterranean

Phenotypic diploidization in plant functional traits uncovered by synthetic neopolyploids in Dianthus broteri

Whole-genome duplication and post-polyploidization genome downsizing play key roles in the evolution of land plants; however, the impact of genomic diploidization on functional traits still remains poorly understood. Using Dianthus broteri as a model, we compared the ecophysiological behaviour of colchicine-induced neotetraploids (4xNeo) to diploids (2x) and naturally occurring tetraploids (4xNat). Leaf gas-exchange and chlorophyll fluorescence analyses were performed in order to asses to what extent post-polyploidization evolutionary processes have affected 4xNat. Genomic diploidization and phenotypic novelty were evident. Distinct patterns of variation revealed that post-polyploidization processes altered the phenotypic shifts directly mediated by genome doubling. The photosynthetic phenotype was affected in several ways but the main effect was phenotypic diploidization (i.e. 2x and 4xNat were closer to each other than to 4xNeo). Overall, our results show the potential benefits of considering experimentally synthetized versus naturally established polyploids when exploring the role of polyploidization in promoting functional divergence.España Ministerio de Ciencia e Innovación project POLYTRANSECO (PGC2018-098358-B-I00)Spanish Ministerio de Universidades (FPU19/02936