Physiological, Biochemical, and Transcriptional Responses to Single and Combined Abiotic Stress in Stress-Tolerant and Stress-Sensitive Potato Genotypes

Potato production is often constrained by abiotic stresses such as drought and high temperatures which are often present in combination. In the present work, we aimed to identify key mechanisms and processes underlying single and combined abiotic stress tolerance by comparative analysis of tolerant and susceptible cultivars. Physiological data indicated that the cultivars Desiree and Unica were stress tolerant while Agria and Russett Burbank were stress susceptible. Abiotic stress caused a greater reduction of photosynthetic carbon assimilation in the susceptible cultivars which was associated with a lower leaf transpiration rate. Oxidative stress, as estimated by the accumulation of malondialdehyde was not induced by stress treatments in any of the genotypes with the exception of drought stress in Russett Burbank. Stress treatment resulted in increases in ascorbate peroxidase activity in all cultivars except Agria which increased catalase activity in response to stress. Transcript profiling highlighted a decrease in the abundance of transcripts encoding proteins associated with PSII light harvesting complex in stress tolerant cultivars. Furthermore, stress tolerant cultivars accumulated fewer transcripts encoding a type-1 metacaspase implicated in programmed cell death. Stress tolerant cultivars exhibited stronger expression of genes associated with plant growth and development, hormone metabolism and primary and secondary metabolism than stress susceptible cultivars. Metabolite profiling revealed accumulation of proline in all genotypes following drought stress that was partially suppressed in combined heat and drought. On the contrary, the sugar alcohols inositol and mannitol were strongly accumulated under heat and combined heat and drought stress while galactinol was most strongly accumulated under drought. Combined heat and drought also resulted in the accumulation of Valine, isoleucine, and lysine in all genotypes. These data indicate that single and multiple abiotic stress tolerance in potato is associated with a maintenance of CO2 assimilation and protection of PSII by a reduction of light harvesting capacity. The data further suggests that stress tolerant cultivars suppress cell death and maintain growth and development via fine tuning of hormone signaling, and primary and secondary metabolism. This study highlights potential targets for the development of stress tolerant potato cultivars

Multiple glacial refugia and contemporary dispersal shape the genetic structure of an endemic amphibian from the Pyrenees

Historical factors (colonization scenarios, demographic oscillations) and contemporary processes (population connectivity, current population size) largely contribute to shaping species’ present-day genetic diversity and structure. In this study, we use a combination of mitochondrial and nuclear DNA markers to understand the role of Quaternary climatic oscillations and present-day gene flow dynamics in determining the genetic diversity and structure of the newt Calotriton asper (Al. Dugès, 1852), endemic to the Pyrenees. Mitochondrial DNA did not show a clear phylogeographic pattern and presented low levels of variation. In contrast, microsatellites revealed five major genetic lineages with admixture patterns at their boundaries. Approximate Bayesian computation analyses and linear models indicated that the five lineages likely underwent separate evolutionary histories and can be tracked back to distinct glacial refugia. Lineage differentiation started around the Last Glacial Maximum at three focal areas (western, central and eastern Pyrenees) and extended through the end of the Last Glacial Period in the central Pyrenees, where it led to the formation of two more lineages. Our data revealed no evidence of recent dispersal between lineages, whereas borders likely represent zones of secondary contact following expansion from multiple refugia. Finally, we did not find genetic evidence of sex-biased dispersal. This work highlights the importance of integrating past evolutionary processes and present-day gene flow and dispersal dynamics, together with multilocus approaches, to gain insights into what shaped the current genetic attributes of amphibians living in montane habitats.info:eu-repo/semantics/publishedVersio

Multiple invasions, Wolbachia and human‑aided transport drive the genetic variability of Aedes albopictus in the Iberian Peninsula

Este artículo contiene 15 páginas, 7 figuras, 1 tabla.The Asian tiger mosquito, Aedes albopictus, is one of the most invasive species in the world. Native to the tropical forests of Southeast Asia, over the past 30 years it has rapidly spread throughout tropical and temperate regions of the world. Its dramatic expansion has resulted in public health concerns as a consequence of its vector competence for at least 16 viruses. Previous studies showed that Ae. albopictus spread has been facilitated by human-mediated transportation, but much remains unknown about how this has affected its genetic attributes. Here we examined the factors that contributed to shaping the current genetic constitution of Ae. albopictus in the Iberian Peninsula, where the species was first found in 2004, by combining population genetics and Bayesian modelling. We found that both mitochondrial and nuclear DNA markers showed a lack of genetic structure and the presence of worldwide dominant haplotypes, suggesting regular introductions from abroad. Mitochondrial DNA showed little genetic diversity compared to nuclear DNA, likely explained by infection with maternally transmitted bacteria of the genus Wolbachia. Multilevel models revealed that greater mosquito fluxes (estimated from commuting patterns and tiger mosquito population distribution) and spatial proximity between sampling sites were associated with lower nuclear genetic distance, suggesting that rapid short- and medium-distance dispersal is facilitated by humans through vehicular traffic. This study highlights the significant role of human transportation in shaping the genetic attributes of Ae. albopictus and promoting regional gene flow, and underscores the need for a territorially integrated surveillance across scales of this disease-carrying mosquito.The research leading to these results has received funding from the Spanish Ministry of Economy and Competitiveness (MINECO, Plan Estatal I+D+I CGL2013-43139-R), “la Caixa” Foundation (ID 100010434) under agreement HR18-00336, and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 853271).Peer reviewe

A fast and inexpensive genotyping system for the simultaneous analysis of human and Aedes albopictus short tandem repeats

Abstract Background: Determination of the interactions between hematophagous mosquitoes and their human hosts is of great importance for better understanding the transmission dynamics of mosquito-borne arboviruses and developing effective strategies to mitigate risk. Genetic analysis of human and mosquito DNA can play a key role in this but commercial kits for human short tandem repeat (STR) genotyping are expensive and do not allow for the simultaneous STR analysis of host and vector DNA. Here, we present an inexpensive and straightforward STR-loci multiplex system capable of simultaneously amplifying Ae. albopictus and human STRs from blood-fed mosquitoes. Additionally, we examine the effect of storage methods and post-feeding time on the integrity of host DNA. Methods: Thirty-five STRs (16 human and 19 Ae. albopictus STRs) subdivided in three multiplexes were tested for amplification and scoring reliability. Under laboratory conditions we compared the efficacy of two preservation methods (absolute ethanol vs. lysis buffer) on the integrity of host DNA in Ae. albopictus blood meals. Furthermore, we evaluated the effect of post-feeding time by sacrificing blood-fed mosquitoes at different time intervals after feeding, and we assessed our ability to detect multiple feedings. To determine if the system can be employed successfully under field conditions, we carried out a preliminary study using field-collected Ae. albopictus. Results: All 35 STRs amplified consistently in the laboratory. Lysis buffer performed better than absolute ethanol in terms of allele peak height and clarity of electropherograms. Complete human DNA profiles could be obtained up to 48h following the blood meal. Analysis of multiple feedings confirmed that peak heights can be used as a proxy to determine post-feeding time and thus derive the number of different people bitten by a mosquito. In the field trial, amplification was successful for 32 STRs. We found human DNA signal in 38 of the 61 field-collected mosquitoes (62%), of which 34 (89%) had ingested a single blood meal, while 4 (11%) contained double meals. Conclusions: Our new genotyping system allows fast and reliable screening of both host and vector species, and can be further adapted to other mosquito species living in close contact with humans

Estat de conservació del cavilat (Cottus hispaniolensis) a la Val d’Aran

E. Carrillo, J. Ninot, T. Buchaca and M. Ventura. Blanes, LIFE+ LIMNOPIRINEUS Technical OfficeEl cavilat (Cottus hispaniolensis) és un dels peixos continentals més amenaçats de Catalunya i Espanya. La seva situació a la Val d’Aran va empitjorar dràsticament arran de les riuades del 2013, fins al punt d’arribar pràcticament a desaparèixer. Des d’aleshores, les poblacions s’han anat recuperant progressivament, amb un lent increment de la seva densitat mitjana i de les localitats ocupades. En part, aquesta recuperació s’ha produït gràcies a actuacions emmarcades en el projecte LIFE+ LimnoPirineus, que s’han dissenyat específicament per a la recuperació d’aquesta espècie dins l’espai de la xarxa Natura 2000 «Aigüestortes » (ES0000022).Peer reviewe

A fast and inexpensive genotyping system for the simultaneous analysis of human and Aedes albopictus short tandem repeats

Background. Determination of the interactions between hematophagous mosquitoes and their human hosts is of great importance for better understanding the transmission dynamics of mosquito-borne arboviruses and developing effective strategies to mitigate risk. Genetic analysis of human and mosquito DNA can play a key role in this, but commercial kits for human short tandem repeat (STR) genotyping are expensive and do not allow for the simultaneous STR analysis of host and vector DNA. Here, we present an inexpensive and straightforward STR-loci multiplex system capable of simultaneously amplifying Aedes albopictus and human STRs from blood-fed mosquitoes. Additionally, we examine the effect of storage methods and post-feeding time on the integrity of host DNA. Methods. Thirty-five STRs (16 human and 19 Ae. albopictus STRs) subdivided in three multiplexes were tested for amplification and scoring reliability. Under laboratory conditions we compared the efficacy of two preservation methods (absolute ethanol vs lysis buffer) on the integrity of host DNA in Ae. albopictus blood meals. We also evaluated the effect of post-feeding time by sacrificing blood-fed mosquitoes at different time intervals after feeding, and we assessed our ability to detect multiple feedings. To determine if the system can be employed successfully under field conditions, we carried out a preliminary study using field-collected Ae. albopictus. Results. All 35 STRs amplified consistently in the laboratory. Lysis buffer performed better than absolute ethanol in terms of allele peak height and clarity of electropherograms. Complete human DNA profiles could be obtained up to 48 h following the blood meal. Analysis of multiple feedings confirmed that peak heights can be used as a proxy to determine post-feeding time and thus derive the number of different people bitten by a mosquito. In the field trial, amplification was successful for 32 STRs. We found human DNA signal in 38 of the 61 field-collected mosquitoes (62%), of which 34 (89%) had ingested a single blood meal, while four (11%) contained double meals. Conclusions. Our new genotyping system allows fast and reliable screening of both host and vector species, and can be further adapted to other mosquito species living in close contact with humans.This work was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 853271)

Estado de conservación del cavilat (Cottus hispaniolensis) en el valle de Arán

E. Carrillo, J. Ninot, T. Buchaca and M. Ventura. Blanes, LIFE+ LIMNOPIRINEUS Technical OfficeEl cavilat (Cottus hispaniolensis) es uno de los peces continentales más amenazados de Cataluña y España. Su situación en el valle de Arán empeoró drásticamente a raíz de las riadas del 2013, hasta el punto de llegar a su práctica desaparición. Desde entonces, sus poblaciones se han ido recuperando progresivamente, con un lento incremento de su densidad media y de las localidades ocupadas. En parte, esta recuperación se ha producido gracias a actuaciones enmarcadas dentro del proyecto LIFE+ LimnoPirineus, que se han diseñado específicamente para la recuperación de esta especie dentro del espacio de Red Natura 2000 de Aigüestortes (ES0000022).Peer reviewe

Conservation status of the pyrenean sculpin (cottus hispaniolensis) in the Aran Valley

E. Carrillo, J. Ninot, T. Buchaca and M. Ventura. Blanes, LIFE+ LIMNOPIRINEUS Technical OfficeThe Pyrenean sculpin (Cottus hispaniolensis) is one of the most threatened freshwater fish in Catalonia and Spain. Its status in the Aran Valley drastically deteriorated as a result of the floods of 2013, to the point of reaching its practical disappearance. Since then, their populations have been progressively recovering, with a slow increase in their average density and occupied localities. In part, this recovery has been produced thanks to actions framed within the LIFE+ LimnoPirineus project, which have been specifically designed for the recovery of this species within the Natura 2000 network space “Aigüestortes” (ES0000022).Peer reviewe

New insights on patterns of genetic admixture and phylogeographic history in Iberian high mountain populations of midwife toads

Este artículo contiene 25 páginas, 7 figuras, 1 tabla.Multiple Quaternary glacial refugia in the Iberian Peninsula, commonly known as “refugia within refugia”, allowed diverging populations to come into contact and admix, potentially boosting substantial mito-nuclear discordances. In this study, we employ a comprehensive set of mitochondrial and nuclear markers to shed light onto the drivers of geographical differentiation in Iberian high mountain populations of the midwife toads Alytes obstetricans and A. almogavarii from the Pyrenees, Picos de Europa and Guadarrama Mountains. In the three analysed mountain regions, we detected evidence of extensive mito-nuclear discordances and/or admixture between taxa. Clustering analyses identified three major divergent lineages in the Pyrenees (corresponding to the eastern, central and central-western Pyrenees), which possibly recurrently expanded and admixed during the succession of glacialinterglacial periods that characterised the Late Pleistocene, and that currently follow a ringshaped diversification pattern. On the other hand, populations from the Picos de Europa mountains (NW Iberian Peninsula) showed a mitochondrial affinity to central-western Pyrenean populations and a nuclear affinity to populations from the central Iberian Peninsula, suggesting a likely admixed origin for Picos de Europa populations. Finally, populations from the Guadarrama Mountain Range (central Iberian Peninsula) were depleted of genetic diversity, possibly as a consequence of a recent epidemic of chytridiomycosis. This work highlights the complex evolutionary history that shaped the current genetic composition of high mountain populations, and underscores the importance of using a multilocus approach to better infer the dynamics of population divergence.This work was supported by the European Commission projects LIFE+ LIMNOPIRINEUS (LIFE13 NAT/ES/001210, PI: M. V.), LIFE RESQUE ALPYR (LIFE20 NAT/ES/00347, PI: M.V.) and Biodiversa FISHME (BiodivRestor- 280, PI: M.V.) and by the Spanish Government projects FUNBIO (RTI2018-096217-B-I00, PI: M. V.), BIOOCULT (2413/2017, PI: M.V.), (Organismo Auto´nomo Parques Nacionales 2399/2017; PI: J.B) and Picos de Europa National Park grants for 2015 and 2016 (PI: J.B.). F.L. had a doctoral grant funded by Fundac¸ão para a Ciência e a Tecnologia (FCT, grant number PD/BD/52598/2014). M.J.J. had an International collaboration grant (National Institute of Ecology) and a postdoctoral grant funded by FCT (grant number SFRH/BPD/109148/ 2015).Peer reviewe

Additional file 1 of A fast and inexpensive genotyping system for the simultaneous analysis of human and Aedes albopictus short tandem repeats

Additional file 1: Figure S1. Map of the study area. Main map shows the Iberian Peninsula, with the Blanes study site marked just above Barcelona. Made with Natural Earth, free vector and raster map data from Natural Earth ( https://www.naturalearthdata.com ). Inset map shows orthophoto of Blanes, with the Marimurtra Botanical Garden field site marked in yellow and the CEAB laboratory marked in blue. Map derived from the Orthophoto of Catalonia 1:5.000 of the Institut Cartogràfic i Geològic de Catalunya (ICGC), used under a CC BY 4.0 license