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Fungal endophytes develop inside plants without visible external signs, and they may confer adaptive advantages to their hosts. Culturing methods have been traditionally used to recognize the fungal endophytic assemblage, but novel metabarcoding techniques are being increasingly applied. This study aims to characterize the fungal endophytic assemblage in shoots, rhizomes and roots of the tall grass Brachypodium rupestre growing in a large area of natural grasslands with a continuum of anthropized disturbance regimes. Seven out of 88 taxa identified via metabarcoding accounted for 81.2% of the reads (Helotiaceae, Lachnum sp. A, Albotricha sp. A, Helotiales A, Agaricales A, Mycena sp. and Mollisiaceae C), revealing a small group of abundant endophytes and a large group of rare species. Although both methods detected the same trends in richness and fungal diversity among the tissues (root > rhizome > shoot) and grasslands (low-diversity >high-diversity grasslands), the metabarcoding tool identified 5.8 times more taxa than the traditional culturing method (15 taxa) but, surprisingly, failed to sequence the most isolated endophyte on plates, Omnidemptus graminis. Since both methods are still subject to important constraints, both are required to obtain a complete characterization of the fungal endophytic assemblage of the plant species. ; M.D. got funding through UPNA's doctorate scholarship. This research was supported by 'la Caixa' Foundation and CAN foundation (LCF/PR/PR13/51080004), Ecoembes-SEO/Birdlife (Libera 2017), Government of Navarra (STEM research project 2018) and Interreg Sudoe Programme, European Regional Development Fund, European-Union, Open2preserve Project (SOE2/P5/E0804).

Pereira E, Vázquez de Aldana BR, San Emeterio L and Zabalgogeazcoa I (2019) A Survey of Culturable Fungal Endophytes From Festuca rubra subsp. pruinosa, a Grass From Marine Cliffs, Reveals a Core Microbiome. Front. Microbiol. 9:3321. doi:10.3389/fmicb.2018.03321 ; Festuca rubra subsp. pruinosa is a perennial grass that inhabits sea cliffs of the Atlantic coasts of Europe. In this unhospitable environment plants grow in rock crevices and are exposed to abiotic stress factors such as low nutrient availability, wind, and salinity. Festuca rubra subsp. pruinosa is a host of the fungal endophyte Epichloe festucae, which colonizes aerial organs, but its root mycobiota is unknown. The culturable endophytic mycobiota of FRP roots was surveyed in a set of 105 plants sampled at five populations in marine cliffs from the northern coast of Spain. In total, 135 different fungal taxa were identified, 17 of them occurred in more than 10% of plants and in two or more populations. Seven taxa belonging to Fusarium, Diaporthe, Helotiales, Drechslera, Slopeiomyces, and Penicillium appeared to be constituents of the core microbiome of Festuca rubra subsp. pruinosa roots because they occurred in more than 20% of the plants analyzed, and at three or more populations. Most fungal strains analyzed (71.8%) were halotolerant. The presence of Epichloe festucae in aboveground tissue was detected in 65.7% of the plants, but its presence did not seem to significantly affect the structure of the core or other root microbiota, when compared to that of plants free of this endophyte. When plants of the grass Lolium perenne were inoculated with fungal strains obtained from Festuca rubra subsp. pruinosa roots, a Diaporthe strain significantly promoted leaf biomass production under normal and saline (200 mM NaCI) watering regimes. These results suggest that the core mycobiome of Festuca rubra subsp. pruinosa could have a role in host plant adaptation, and might be useful for the improvement of agricultural grasses. ; This study has received funding from the European Union's Horizon 2020 Research and Innovation Program under the Marie Sklodowska-Curie grant agreement no. 676480. LS was funded through a Talent Recruitment grant from "Obra Social La Caixa-Fundacion CAN". We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

A pesar de su relevancia social creciente, la ciencia ecológica y ambiental está pasando por momentos muy bajos en los programas educativos de secundaria y bachillerato en nuestro país. En muchos centros escolares, la oferta de esta materia es inexistente en bachillerato y los métodos didácticos utilizados fomentan poco la motivación y el aprendizaje del alumnado. En consecuencia, el escaso valor que está recibiendo esta ciencia en la educación reglada acaba afectando a las opciones elegidas por los estudiantes para sus estudios de grado superior y universitarios. Este artículo describe una experiencia educativa llevada a cabo por el grupo de investigación en Ecología y Medio Ambiente de la Universidad Pública de Navarra (UPNA) y financiada por el Departamento de Educación del Gobierno de Navarra con el fin de introducir el trabajo de una científica ambiental a 12 niñas de 4 centros escolares. Se buscaba despertar su interés por este campo científico, vehiculizar a través de ellas esta ciencia a sus compañeros de colegio, y finalmente profundizar con los docentes implicados en esta problemática educativa. ; Despite its growing social relevance, ecological and environmental science is declining in highschool educational programs in Spain. In many schools, this matter does not exist in the highest courses and, in elementary courses, the teaching methods used do not promote student motivation for learning. Due to the limited value that this science is receiving in the formal education, a low number of students is opting for a career related to the natural sciences. This article describes an educational experience carried out by the Ecology and Environment research group of the Public University of Navarra (UPNA) and funded by the Department of Education of the Government of Navarra, in which the work of an environmental scientist was introduced to 12 girls from four schools. The aim was to raise their interest in this scientific field, to convey through them this science to their classmates, and finally to deepen with the school teachers in this educational problem. ; Agradecimientos al Departamento de Educación del Gobierno de Navarra, por la ayuda económica concedida para llevar a cabo este proyecto.

Plant-soil feedback mechanisms influence the abundance and rarity of plant species and can favour invasive processes, including those of native species. To explore these mechanisms, we analysed correlations between spatial distributions of plant biomass and soil properties in two neighbouring grasslands at different phases of expansion of the native Eurasian tall-grass Brachypodium rupestre (Host) Roem & Schult (B. rupestre cover: >75 and 25–50%). For this, we applied spatially explicit sampling, geostatistical analysis and structural equation models (SEM) to probe causal relationships among measured variables involved in nutrient accumulation. We hypothesized that if litter accumulates as a result of reduced grazing, 'fertility islands' (spots of high SOM and nutrient contents) will form under B. rupestre clumps because the increase in resource inputs from litter will trigger SOM build-up and promote microbial growth. Our results show that 'fertility islands' of P and amino acids occurred under the patchy clumps of B. rupestre in the less invaded grassland. In addition, the SEMs indicated that nutrient accumulation was partially due to mineralization of the SOM and modulated by the soil microbial biomass. However, there was no correlation between spatial patterns of B. rupestre biomass, SOM and microbial biomass. Moreover, the SEMs explained small amounts of variance in them (SOM r2 = 0.22 and microbial biomass r2 = 0.08), suggesting that factors other than B. rupestre biomass were responsible for the high fertility below the patches. Our spatially explicit approach demonstrated that litter inputs in dense temperate grassland communities can generate 'fertility islands' that may favour the stability and expansion of a tall-grass invader and suggest that herbivory may enhance or inhibit this phenomenon. ; The study was funded by 'la Caixa' Foundation, Spain and CAN foundation, Spain (LCF/PR/PR13/51080004), the Ministry of Science and Innovation of the Spanish Government (project refs. CGL2010-21963, CGL2011-29746 and CGL2017-85490-R), and Interreg Sudoe Programme, European Regional Development Fund, European-Union, Open2preserve Project (SOE2/P5/E0804). L. Múgica and M. Durán were funded through a UPNA Research Staff Training Grant.

Incluye material complementario ; Grasslands are one of the major sinks of terrestrial soil organic carbon (SOC). Understanding how environmental and management factors drive SOC is challenging because they are scale-dependent, with large-scale drivers affecting SOC both directly and through drivers working at small scales. Here we addressed how regional, landscape and grazing management, soil properties and nutrients, and herbage quality factors affect 20 cm depth SOC stocks in mountain grasslands in the Pyrenees. Taking advantage of the high variety of environmental heterogeneity in the Pyrenees, we built a dataset (n = 128) that comprises a wide range of environmental and management conditions. This was used to understand the relationship between SOC stocks and their drivers considering multiple environments. We found that temperature seasonality (difference between mean summer temperature and mean annual temperature; TSIS) was the most important geophysical driver of SOC in our study, depending on topography and management. TSIS effects on SOC increased in exposed hillsides, slopy areas, and relatively intensively grazed grasslands. Increased TSIS probably favours plant biomass production, particularly at high altitudes, but landscape and grazing management factors regulate the accumulation of this biomass into SOC. Concerning biochemical SOC drivers, we found unexpected interactive effects between grazer type, soil nutrients and herbage quality. Soil N was a crucial SOC driver as expected but modulated by livestock species and neutral detergent fibre contenting plant biomass; herbage recalcitrance effects varied depending on grazer species. These results highlight the gaps in knowledge about SOC drivers in grasslands under different environmental and management conditions. They may also serve to generate testable hypotheses in later/future studies directed to climate change mitigation policies. ; Research in this paper is based on the PAS-TUS Database, which was compiled from different funding sources over time, the most relevant being the EU Interreg III-A Programme (I3A-4-147-E) and the POCTEFA Programme/Interreg IV-A (FLUXPYR, EFA 34/08); the Spanish Science Foundation FECYT-MICINN (CARBOPAS: REN2002-04300-C02-01; CAR-BOAGROPAS: CGL2006-13555-C03-03 and CAPAS: CGL2010-22378-C03-01); and the Foundation Catalunya-La Pedrera and the Spanish Institute of Agronomical Research INIA (CARBO-CLUS: SUM2006-00029-C02-0). Leticia San Emeterio was funded through a Talent Recruitment grant from Obra Social La Caixa- Fundación CAN. The ARAID Foundation provided support to Juan José Jiménez. This work was funded by the Spanish Science Foundation FECYT-MINECO (projects BIOGEI: GL2013-49142-C2-1-R and IMAGINE: CGL2017-85490-R) and the University of Lleida (PhD Fellowship to Antonio Rodríguez).