Constraints to speciation despite divergence in an old haplochromine cichlid lineage.

Most of the 500+ cichlid species of Lake Victoria evolved very rapidly in the wake of an adaptive radiation within the last 15'000 years. All 500 species have evolved from just one out of five old cichlid lineages that colonized the lake. Endemic to the Lake Victoria region, Astatoreochromis alluaudi is a member of an old haplochromine lineage that never speciated in the region. Even though the species occurs in a wide range of habitats, there were no indications of evolutionary diversification. Here, we tested predictions of several hypothetical mechanisms that might constrain speciation, including high dispersal rates, a generalist life style and the lack of behavioral assortative mating. Genomic analyses of individuals from thirteen populations revealed several genomically distinct groups, associated with major habitat classes, indicating the existence of two distinct ecotypes. We found significant phenotypic differences between these ecotypes in the wild, which were retained under common-garden conditions, potentially indicating heritable phenotypic adaptations. Female mate choice experiments revealed the absence of behavioural assortative mating despite genetic and phenotypic differentiation between ecotypes. We suggest that the lack of coupling between behavioral mating preferences and phenotypic and genetic divergence constrains speciation in this cichlid

Beyond skin-deep: targeting the plant surface for crop improvement

The aboveground plant surface is a well-adapted tissue layer that acts as an interface between the plant and its surrounding environment. As such, its primary role is to protect against desiccation and maintain the gaseous exchange required for photosynthesis. Further, this surface layer provides a barrier against pathogens and herbivory, while attracting pollinators and agents of seed dispersal. In the context of agriculture, the plant surface is strongly linked to postharvest crop quality and yield. The epidermal layer contains several unique cell types adapted for these functions, while the nonlignified aboveground plant organs are covered by a hydrophobic cuticular membrane. This review aims to provide an overview of the latest understanding of the molecular mechanisms underlying crop cuticle and epidermal cell formation, with focus placed on genetic elements contributing towards quality, yield, drought tolerance, herbivory defence, pathogen resistance, pollinator attraction and sterility, while highlighting the interrelatedness of plant surface development and traits. Potential crop improvement strategies utilising this knowledge are outlined in the context of the recent development of new breeding technique

Nitrogen control of transpiration in grapevine

Transpiration per unit of leaf area is the end-product of the root-to-leaf water transport within the plant, and it is regulated by a series of morpho-physiological resistances and hierarchical signals. The rate of water transpired sustains a series of processes such as nutrient absorption and leaf evaporative cooling, with stomata being the end-valves that maintain the optimal water loss under specific degrees of evaporative demand and soil moisture conditions. Previous work provided evidence of a partial modulation of water flux following nitrogen availability linking high nitrate availability with tight stomatal control of transpiration in several species. In this work, we tested the hypothesis that stomatal control of transpiration, among others signals, is partially modulated by soil nitrate ( NO3- ) availability in grapevine, with reduced NO3- availability (alkaline soil pH, reduced fertilization, and distancing NO3- source) associated with decreased water-use efficiency and higher transpiration. We observed a general trend when NO3- was limiting with plants increasing either stomatal conductance or root-shoot ratio in four independent experiments with strong associations between leaf water status, stomatal behavior, root aquaporins expression, and xylem sap pH. Carbon and oxygen isotopic signatures confirm the proximal measurements, suggesting the robustness of the signal that persists over weeks and under different gradients of NO3- availability and leaf nitrogen content. Nighttime stomatal conductance was unaffected by NO3- manipulation treatments, while application of high vapor pressure deficit conditions nullifies the differences between treatments. Genotypic variation for transpiration increase under limited NO3- availability was observed between rootstocks indicating that breeding (e.g., for high soil pH tolerance) unintentionally selected for enhanced mass flow nutrient acquisition under restrictive or nutrient-buffered conditions. We provide evidence of a series of specific traits modulated by NO3- availability and suggest that NO3- fertilization is a potential candidate for optimizing grapevine water-use efficiency and root exploration under the climate-change scenario

Mining grapevine downy mildew susceptibility genes: a resource for genomics-based breeding and tailored gene editing

Several pathogens continuously threaten viticulture worldwide. Until now, the investigation on resistance loci has been the main trend to understand the interaction between grapevine and the mildew causal agents. Dominantly inherited gene-based resistance has shown to be race-specific in some cases, to confer partial immunity, and to be potentially overcome within a few years since its introgression. Recently, on the footprint of research conducted in Arabidopsis, putative genes associated with downy mildew susceptibility have been discovered also in the grapevine genome. In this work, we deep-sequenced four putative susceptibility genes—namely VvDMR6.1, VvDMR6.2, VvDLO1, VvDLO2—in 190 genetically diverse grapevine genotypes to discover new sources of broad-spectrum and recessively inherited resistance. Identified Single Nucleotide Polymorphisms were screened in a bottleneck analysis from the genetic sequence to their impact on protein structure. Fifty-five genotypes showed at least one impacting mutation in one or more of the scouted genes. Haplotypes were inferred for each gene and two of them at the VvDMR6.2 gene were found significantly more represented in downy mildew resistant genotypes. The current results provide a resource for grapevine and plant genetics and could corroborate genomic-assisted breeding programs as well as tailored gene editing approaches for resistance to biotic stresse

Mining downy mildew susceptibility genes: a diversity study in grapevine

Several pathogens continuously threaten viticulture worldwide. Until now, the investigation on resistance loci has been the main trend to understand the interaction between grapevine and mildew causal agents. Dominantly inherited gene-based resistance has shown to be race-specific in some cases, to confer partial immunity and to be potentially overcome within a few years since its introgression. Recently, on the footprint of research conducted on Arabidopsis, the putative hortologues of genes associated with downy mildew susceptibility in this species, have been discovered also in the grapevine genome. In this work, we deep-resequenced four putative susceptibility genes in 190 highly genetically diverse grapevine genotypes to discover new sources of broad-spectrum recessively inherited resistance. The scouted genes are VvDMR6-1, VvDMR6-2, VvDLO1, VvDLO2 and predicted to be involved in susceptibility to downy mildew. From all identified mutations, 56% were Single Nucleotide Polymorphisms (SNPs) in heterozygosity, while the remaining 44% were homozygous. Regarding the identified mutations with putative impact on gene function, we observed ~4% genotypes mutated in VvDMR6-1 and ~8% mutated in VvDMR6-2, only a handful of genotypes that were mutated in both genes. ~2% and ~7% genotypes showed mutations in VvDLO1 and VvDLO2 respectively, and again a few genotypes resulted mutated in both genes. In particular, 80% of impacting mutations were heterozygous while 20% were homozygous. The current results will inform grapevine genetics and corroborate genomic-assisted breeding programs for resistance to biotic stresses

Development and initial testing of the self‐care of chronic illness inventory

Aim The aim was to develop and psychometrically test the self‐care of chronic illness Inventory, a generic measure of self‐care. Background Existing measures of self‐care are disease‐specific or behaviour‐specific; no generic measure of self‐care exists. Design Cross‐sectional survey. Methods We developed a 20‐item self‐report instrument based on the Middle Range Theory of Self‐Care of Chronic Illness, with three separate scales measuring Self‐Care Maintenance, Self‐Care Monitoring, and Self‐Care Management. Each of the three scales is scored separately and standardized 0–100 with higher scores indicating better self‐care. After demonstrating content validity, psychometric testing was conducted in a convenience sample of 407 adults (enrolled from inpatient and outpatient settings at five sites in the United States and ResearchMatch.org). Dimensionality testing with confirmatory factor analysis preceded reliability testing. Results The Self‐Care Maintenance scale (eight items, two dimensions: illness‐related and health‐promoting behaviour) fit well when tested with a two‐factor confirmatory model. The Self‐Care Monitoring scale (five items, single factor) fitted well. The Self‐Care Management scale (seven items, two factors: autonomous and consulting behaviour), when tested with a two‐factor confirmatory model, fitted adequately. A simultaneous confirmatory factor analysis on the combined set of items supported the more general model. Conclusion The self‐care of chronic illness inventory is adequate in reliability and validity. We suggest further testing in diverse populations of patients with chronic illnesses

How do different residential consumer groups react to monetary and unconventional non-monetary incentives to reduce their electricity consumption? : final report

Zur Realisierung der Ziele der Energiestrategie 2050 gewinnt die Nachfragesteuerung von Verbrauchenden für Energieversorgungsunternehmen (EVU) zunehmend an Bedeutung. Energieeffizienz bedarf dabei nebst technischer Lösungen auch Ansätzen zur Verhaltensänderung. Anreize sind eine Möglichkeit für EVU, ihre Kundschaft zum Energiesparen zu motivieren. Im Projekt wird erforscht, ob unkonventionelle nicht-monetäre Anreize besonders geeignet sind, Haushalte zum Stromsparen zu bewegen. Dazu wurden im ersten Schritt qualitative Experteninterviews mit Vertretern von Energieunternehmen durchgeführt, um realitätsnahe Anreize zu identifizieren. Anschliessend prüften wir diese Anreize in zwei Online-Experimente (N = 805 und N = 1106) auf ihre Wirkung auf die Stromsparabsicht - sowohl allgemein wie auch für spezifische Verbrauchergruppen. Im ersten Experiment zeigte sich, dass Gebühren auf niedrige Akzeptanz trafen. Des Weiteren war die Energiespar-Absicht bei monetären und unkonventionellen Belohnungen nicht höher als bei blosser Aufforderung zum Energiesparen. Verschiedene sozioökonomische Gruppen reagierten gleich auf die Anreize. Jedoch reagierten Gruppen mit hohem Umweltbewusstsein besonders positiv auf Belohnungssysteme und Energiespar-Aufforderungen ohne Anreiz. Im zweiten Experiment wurde die Wirkung monetärer Anreize mit der Wirkung einer Auswahl von unkonventionellen Anreizen verglichen. Eine Auswahl zwischen Gutscheinen für alltägliche Dienstleistungen (z.B. öffentliche Verkehrsmittel, Lebensmittelgeschäfte) motivierte die Teilnehmenden am stärksten, Strom zu sparen. Verschiedene Belohnungen und die Aufforderung zum Energiesparen wirkten gleichermassen positiv auf die Loyalität der Verbrauchenden zum Energieunternehmen. Insgesamt schnitten bei Haushalten mit geringem Interesse an Energie-Themen unkonventionelle Anreize nicht besser ab als andere Anreizsysteme. Beide Experimente zeigten jedoch, dass Verbrauchende die Förderung von Energiesparverhalten durch EVU als positiv wahrnehmen. Auch zeigte sich, dass sie Interesse daran haben, mehr über ihren eigenen Energieverbrauch zu erfahren. Das Projekt bietet eine Grundlage, um verschiedene Ansätze der Sensibilisierung zum Energiesparen in der Realität anzuwenden und weiterzuentwickeln.Demand-side management is becoming more relevant for energy utilities to reach the goals of the Swiss Energy Strategy 2050. Besides technical approaches to increase energy efficiency, approaches for behavioural change are also necessary. Here, energy utilities may use incentives to engage the public and their customers, in particular. The key idea of this project is to examine if unconventional non-monetary incentives are particularly successful in engaging households to save electricity through behavioural change. Therefore, we first conducted a series of qualitative expert interviews with representatives of energy utilities to identify suitable incentives. Subsequently, we conducted two large-scale online experiments (N = 805 and 1,106) to examine which incentive schemes are most effective in general, and for certain consumer groups. The first experiment revealed that fees receive low acceptance and energy-saving intentions were not higher when monetary or unconventional rewards were offered compared to a condition without incentives. Moreover, disparate socio-economic groups did not differ in their intention to change their behaviour for various incentives, in contrast to groups varying in their awareness of energy issues. The second experiment offered participants a choice of incentives. Here, a choice among coupons that can be used on a day-to-day basis (e.g. coupons for public transport and supermarkets) most motivated participants to change their behaviour. As in the first experiment, we found no alterations among socio-economic groups; incentives did not have a differing effect on participants’ customer loyalty to the energy utility. Taken together, both experiments suggest that unconventional incentives are not more successful compared to other types of incentives to engage customers that, thus far, have been uninterested in energy issues. However, both experiments suggest that energy utilities’ promotion of energy saving through behavioural change was highly welcomed by participants in general. In addition, both experiments suggest that participants are keen to learn about their own energy consumption. Hence, the project provides a rich basis for starting a real-world field trial to further explore the energy-saving potential of different types of incentives

Using OneGenE and Grapedia resources to support research in grapevine physiology

Causal relation discovery from observational data is a recent research topic that is being actively studied both theoretically and technically. The OneGenE project applied a causal inference method, the PC algorithm, to big homogeneous datasets of transcriptomic data, such as the Vespucci v1 (2016) and the more recent Vespucci v2 (2021) datasets for Vitis vinifera. To deal with the high computational complexity and large amount of input data, OneGenE method was applied in the framework of distributed computing, within the BOINC project based on volunteers’ availability to run OneGenE on their desktops. The output is represented by a list of causally associated genes for every input gene of the Vespucci matrix, based on the 12X.V1 release of grapevine genome. The next step has been the delivery of this information to the biologists through a website and the development of tools which take it as input for further exploration and analysis. The final aim would be to reconstruct gene regulatory networks, where genes are connected by means of oriented edges representing causal relationships. This model would support gene functional studies and system biology approaches to interpret relevant aspects of plant physiology. The information has been published according to the FAIR principles of data management, and the opportunity to integrate it inside Grapedia is unvaluable to improve its accessibility and usability, as already occurring for the gene annotation integrated from the Gene Ref Catalogue resource. Regulatory networks related to floral initiation and organ specification will be presented as examples

Regeneration of non-chimeric plants from DNA-free edited grapevine protoplasts

The application of New Breeding Techniques (NBTs) in Vitis vinifera is highly desirable to introduce valuable traits while preserving the genotype of the elite cultivars. However, a broad application of NBTs through standard DNA-based transformation is poorly accepted by public opinion and law regulations in Europe and other countries due to the stable integration of exogenous DNA, which leads to transgenic plants possibly affected by chimerism. A single-cell based approach, coupled with a DNA-free transfection of the CRISPR/Cas editing machinery, constitutes a powerful tool to overcome these problems and maintain the original genetic make-up in the whole organism. We here describe a successful single-cell based, DNA-free methodology to obtain edited grapevine plants, regenerated from protoplasts isolated from embryogenic callus of two table grapevine varieties (V. vinifera cv. Crimson seedless and Sugraone). The regenerated, non-chimeric plants were edited on the downy- and powdery-mildew susceptibility genes, VviDMR6 and VviMlo6 respectively, either as single or double mutant

Resistance to Plasmopara viticola in a grapevine segregating population is associated with stilbenoid accumulation and with specific host transcriptional responses

<p>Abstract</p> <p>Background</p> <p>Downy mildew, caused by the oomycete <it>Plasmopara viticola</it>, is a serious disease in <it>Vitis </it><it>vinifera</it>, the most commonly cultivated grapevine species. Several wild <it>Vitis </it>species have instead been found to be resistant to this pathogen and have been used as a source to introgress resistance into a <it>V. vinifera </it>background. Stilbenoids represent the major phytoalexins in grapevine, and their toxicity is closely related to the specific compound. The aim of this study was to assess the resistance response to <it>P. viticola </it>of the Merzling × Teroldego cross by profiling the stilbenoid content of the leaves of an entire population and the transcriptome of resistant and susceptible individuals following infection.</p> <p>Results</p> <p>A three-year analysis of the population's response to artificial inoculation showed that individuals were distributed in nine classes ranging from total resistance to total susceptibility. In addition, quantitative metabolite profiling of stilbenoids in the population, carried out using HPLC-DAD-MS, identified three distinct groups differing according to the concentrations present and the complexity of their profiles. The high producers were characterized by the presence of <it>trans</it>-resveratrol, <it>trans</it>-piceid, <it>trans</it>-pterostilbene and up to thirteen different viniferins, nine of them new in grapevine.</p> <p>Accumulation of these compounds is consistent with a resistant phenotype and suggests that they may contribute to the resistance response.</p> <p>A preliminary transcriptional study using cDNA-AFLP selected a set of genes modulated by the oomycete in a resistant genotype. The expression of this set of genes in resistant and susceptible genotypes of the progeny population was then assessed by comparative microarray analysis.</p> <p>A group of 57 genes was found to be exclusively modulated in the resistant genotype suggesting that they are involved in the grapevine-<it>P. viticola </it>incompatible interaction. Functional annotation of these transcripts revealed that they belong to the categories defense response, photosynthesis, primary and secondary metabolism, signal transduction and transport.</p> <p>Conclusions</p> <p>This study reports the results of a combined metabolic and transcriptional profiling of a grapevine population segregating for resistance to <it>P. viticola</it>. Some resistant individuals were identified and further characterized at the molecular level. These results will be valuable to future grapevine breeding programs.</p