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BACKGROUND: The colonization of land and the diversification of terrestrial plants is intimately linked to the evolutionary history of their symbiotic fungal partners. Extant representatives of these fungal lineages include mutualistic plant symbionts, the arbuscular mycorrhizal (AM) fungi in Glomeromycota and fine root endophytes in Endogonales (Mucoromycota), as well as fungi with saprotrophic, pathogenic and endophytic lifestyles. These fungal groups separate into three monophyletic lineages but their evolutionary relationships remain enigmatic confounding ancestral reconstructions. Their taxonomic ranks are currently fluid. RESULTS: In this study, we recognize these three monophyletic linages as phyla, and use a balanced taxon sampling and broad taxonomic representation for phylogenomic analysis that rejects a hard polytomy and resolves Glomeromycota as sister to a clade composed of Mucoromycota and Mortierellomycota. Low copy numbers of genes associated with plant cell wall degradation could not be assigned to the transition to a plant symbiotic lifestyle but appears to be an ancestral phylogenetic signal. Both plant symbiotic lineages, Glomeromycota and Endogonales, lack numerous thiamine metabolism genes but the lack of fatty acid synthesis genes is specific to AM fungi. Many genes previously thought to be missing specifically in Glomeromycota are either missing in all analyzed phyla, or in some cases, are actually present in some of the analyzed AM fungal lineages, e.g. the high affinity phosphorus transporter Pho89. CONCLUSION: Based on a broad taxon sampling of fungal genomes we present a well-supported phylogeny for AM fungi and their sister lineages. We show that among these lineages, two independent evolutionary transitions to mutualistic plant symbiosis happened in a genomic background profoundly different from that known from the emergence of ectomycorrhizal fungi in Dikarya. These results call for further reevaluation of genomic signatures associated with plant symbiosis.

Purpose: To protect the environment and society, research on responsible behavior and personal values has increased. Values have been identified as important for understanding and predicting environmental preservation behaviors. The purpose of this study is to analyze the validity and reliability of the Environmental Portrait Value Questionnaire in the Spanish context. Design/methodology/approach: The new version of this questionnaire was administered to 742 university students (46.4% male and 53.6% female) from 16 regions in Spain. Findings: The results of adapting and testing the instrument's psychometric properties were consistent with accepted criteria for validity and reliability. Therefore, this updated and contextualized instrument has the potential to contribute to academic advances in the sense of expanding the empirical practice of studying environmental values. Fifteen items from the original version were retained, grouped into four factors as in the original version: Altruistic -- five items; Egoistic -- four items; Biospheric -- three items; and Hedonic -- three items. The final version showed adequate fit indices and reliability measures. Originality/value: This instrument is a powerful resource for the Spanish academic community because using this application it will be possible to assess the degree of commitment of young adults to the goals of sustainability and environmental protection.

Social entrepreneurship is a research topic that has received great attention from academics especially in recent years. However, the results in the literature are far from univocal, for example, there is no clear conceptual delimitation of the term, and it is often analyzed using the same theoretical models of traditional entrepreneurship. With the present study, we have attempted to overcome this problem by analyzing different antecedents, closer to the social and emotional universe, and detached from a male-centric and traditional vision of entrepreneurship, with the aim of understanding social entrepreneurial intentions in higher education. Results obtained from a sample of 962 college students showed that prior experience with social problems (PESP) and empathy (EMP) have a significant and positive impact on social entrepreneurial intention (SEI). Furthermore, social self-efficacy (SES-E), moral obligation (MO), and perceived social support (PSS), in addition to directly influencing SEI, mediated the relationship between PESP-SEI, and the relationship between EMP-SEI. More interestingly, gender (male vs female), but not the different type of study (social sciences vs economics and business sciences), moderated the relationship between EMP-SEI to the benefit of women. Given the importance of social entrepreneurship as an alternative solution to the current economic crisis, these are important results because, on the one hand, they make it possible to overcome the male-female gap that characterizes traditional entrepreneurship, on the other, they underline the need to introduce different constructs closer to the social and emotional sphere into entrepreneurship education programs.

Abstract Due to its extreme conditions, microbial life in the Atacama Desert is known to survive in well-protected micro-habitats (hypolithic, endolithic, etc.), but rarely directly exposed to the environment, that is, epilithic habitats. Here we report a unique site, La Portada, a cliff confronting the Pacific Ocean in the Coastal Range of this desert, in which the constant input of water provided by the sea spray allows for the growth of a black-colored epilithic subaerial microbial ecosystem. Formed by a complex community of halophilic microorganisms belonging to the three domains of life, this ecosystem displays the typical three-dimensional structure of benthic microbialites, coherent with the presence of a diversity of cyanobacteria (including species from the genera that are known to form them), a constant high water activity and an ample availability of carbonate ions. From these microbialites we isolated Hortae werneckii, a fungal species which by producing melanin, not only explains the dark color of these microbialites, but may also play the role of protecting the whole community from extreme UV radiation. A number of biosignatures not only confirmed sea spray as the main source of water, but also suggests that one place to consider for the search of evidences of life on Mars would be on the paleo-coastlines that surrounded vanished oceans such as that on Aeolis Dorsa.

Abstract The agronomic use of compost and biochar as soil amendments may exhibit contrasting results in terms of soil fertility and plant nutrition. The effects of the biennial application of biochar, compost and a blend of compost:biochar (90:10; % dw:dw) on the agronomical performance of an organically managed and well established 25-year-old olive orchard was assessed 5 years after the initial application. The agronomical evaluation was based on the assessment of the soil physical, chemical, and biological characteristics, and the assessment of the soil fertility by both crop production and nutritional status of the orchard, and the bioassay with olive plantlets. Biochar mainly benefited the physical properties (bulk density, total porosity, aeration, water retention capacity) of soil, especially in the top 0–5 cm. Compost and its blend with biochar improved microbial activity, soil nutritional status (increasing the content of soluble organic C, N, and P) and favoured the formation of aggregates in soil. The bioassay conducted with young plantlets confirmed the enhanced soil fertility status in the three amended treatments, particularly in the case of biochar and its blend with compost. However, this effect was not significantly observed in the adult plants after 5 years of application, reflecting the slow response of adult olive trees to changes in fertilization. Based on these results, alongside the desirable long-residence time of biochar in soil and the ready availability of compost, the blend of biochar with compost assayed in this study is defined as a valid strategy for preparing high quality soil organic amendments.