0000000001253330

AUTHOR

Alberto Guillén

Tipificación y estatus taxonómico de Centaurea resupinata subsp. virens (sect. Willkommia Blanca, Asteraceae)

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Tipificación de dos nombres linneanos del género <em>Erigeron</em> L. (<em>Compositae</em>)

Se presenta la lectotipificación del nombre Erigeron glutinosus L., con una ilustración de Barrelier de 1714 y de E. tuberosus L., con un ejemplar del herbario UPS-BURSER.

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Effects of environmental and temporal factors on Glomeromycotina spores in sand dunes along the Gulf of Valencia (Spain)

Abstract AMF symbiosis in sand dunes is the key for maintenance of stable vegetation. The main goal of this work was to determine the effects of environmental and temporal factors on AMF living in sand dunes (Gulf of Valencia, Spain). Soil samples were collected seasonally at 6 sites, during 2 yrs, from three habitats and four plant species and the frequency and relative abundance of AMF was examined. AMF were more frequent in mobile than in embryonic dunes, in spring and in sites with old vegetation. Ten AMF species were identified, their distribution depending mainly on the anthropogenic disturbance of the site. Gigasporaceae Cetraspora sp. and Dentiscutata sp. preferred undisturbed soil …

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<p><strong><em>Scutellospora deformata</em></strong><strong> (Scutellosporaceae), a new species of Gigasporales from the Mediterranean sand dunes of Spain</strong></p>

A new species S. deformata, that occurs in six locations of marine sand dunes along the eastern Mediterranean coast of Spain is described and illustrated from spores. In the field, the species occurred in the rhizosphere of Ammophila arenaria (Poaceae), Elymus farctus (Poaceae), Otanthus maritimus (Asteraceae), and Echinophora spinosa (Apiaceae). Morphological characters related with outer, middle and inner wall of the glomerospores as well as phylogenetic analysis (partial SSU, ITS1-5.8S region and the partial LSU nrDNA) support the hypothesis that the fungus is a new species of the Scutellosporaceae.

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Preparation of Samples for Characterization of Arbuscular Mycorrhizal Fungi

Arbuscular mycorrhizal fungi (AMF) are an important element of the plant microbiome as they establish an endosymbiotic relationship with the roots of most plant species. This association enhances access to nutrients and water for plants, and provides the fungus with plant-derived organic carbon. In this chapter, I describe a range of methods to work with AMF including: soil sampling; isolation of AMF propagules (spores, sporocarps, roots, and mycelium) by a wet sieving and centrifugation in a sucrose solution; trap (from field soil with AMF spores) and one-species pot cultures (from AMF spores divided into morphotypes); staining of mycorrhizae in plant roots; and production of diagnostic sl…

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Sobre la variabilidad infraespecífica de Sideritis fruticulosa Pourr. (Labiatae)

The taxonomy, nomenclature, chorology and phytosociology of Sideritis fruticulosa (Labiatae) are reviewed. We propose the division of this taxon in four subspecies (subsp. fruticulosa, subsp. cavanillesii, subsp. ferreriana, and subsp. tarraconensis), one of which (subsp. ferreriana) is described in this paper. Besides, a new variety is proposed: S. fruticulosa subsp. cavanillesii var. illerdensis. The name Sideritis ×llenasii is lectotypified

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Optimal Pruned K-Nearest Neighbors: OP-KNN Application to Financial Modeling

The paper proposes a methodology called OP-KNN, which builds a one hidden-layer feed forward neural network, using nearest neighbors neurons with extremely small computational time. The main strategy is to select the most relevant variables beforehand, then to build the model using KNN kernels. Multi-response sparse regression (MRSR) is used as the second step in order to rank each k-th nearest neighbor and finally as a third step leave-one-out estimation is used to select the number of neighbors and to estimate the generalization performances. This new methodology is tested on a toy example and is applied to financial modeling.

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Biogeography of arbuscular mycorrhizal fungal spore traits along an aridity gradient, and responses to experimental rainfall manipulation

Abstract Spore size, colour and melanin content are hypothesised to be functional in relation to environmental stress. Here, we studied AM fungal spores in arid environments of Australia and in an experimental platform simulating altered rainfall. We used microscopy and image analysis to measure spore colour and size, and a quantitative colorimetric assay to estimate melanin content in spores. In arid sites, melanin content tended to increase with increasing aridity. We observed a large range of spore colours at all sites but found a higher proportion of both dark and light spores, and fewer intermediate colours, in drier sites. Spore abundance and size varied among sites, but neither were …

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<p><strong><em>Diversispora valentina</em></strong><strong> (Diversisporaceae), a new species of arbuscular mycorrhizal fungi from the Mediterranean sand dunes of Spain</strong></p>

A new arbuscular mycorrhizal fungal species, Diversispora valentina, is described and illustrated. In the field, this species is associated with marine dunes located along the Mediterranean coast in eastern Spain. Spores of D. valentina occurred in sporocarps, in clusters, and singly in the soil or inside the roots of Ammophila arenaria (Poaceae), Elymus farctus (Poaceae), Otanthus maritimus (Asteraceae), and Echinophora spinosa (Apiaceae) in the six locations studied. A single-species culture of D. valentina was obtained using Trifolium repens as a host plant. The small subunit internal transcribed spacer and large subunit (SSU-ITS1-5.8S-ITS2-LSU) nrDNA sequences place the new species in t…

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A new subspecies of Rosmarinus officinalis (Lamiaceae) from the eastern sector of the Iberian Peninsula

Rosmarinus officinalis subsp. valentinus (Lamiaceae) is described as a new subspecies in the flora of the Iberian Peninsula. The diagnostic characters for the subsp. valentinus include several morphological differences, mainly based on a distinctly prostrate habit, a reduced leaf size, smaller calyx and corolla, and white flower. A comparative table with diagnostic morphological features to distinguish among the three subspecies of the R. officinalis is provided. Habitat, ecology, greenhouse cultivation and phenolic profile are also considered.

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Glomus ibericum, Septoglomus mediterraneum, and Funneliformis pilosus, three new species of arbuscular mycorrhizal fungi

Three new arbuscular mycorrhizal fungal species—Glomus ibericum, Septoglomus mediterraneum, and Funneliformis pilosus—are described and illustrated. In the field, the three species were associated with roots of Ammophila arenaria (Poaceae), Elymus farctus (Poaceae), Otanthus maritimus (Asteraceae), and Echinophora spinosa (Apiaceae) colonizing maritime dunes located along the Mediterranean coast in eastern Spain. The novelty of these species is supported by morphological, molecular, and phylogenetic analyses. Single-species cultures of S. mediterraneum and F. pilosus were obtained using Trifolium repens as a host plant, both forming arbuscular mycorrhizae, whereas single-species cultures fr…

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Typification of the Linnaean name Centaurea seridis (Asteraceae)

The genus Centaurea Linnaeus (1753: 909) (Asteraceae) comprises a large number of taxa mainly occurring in the Mediterranean region and southwest Asia (Susanna & Garcia-Jacas 2007). Centaurea seridis Linnaeus (1753: 915) is distributed from south Europe (Spain incl. Balearic Islands, Italy incl. Sicily, France, Albania and Greece) to northwest Africa (Algeria, Morocco and Tunisia). From a nomenclatural standpoint, Centaurea seridis has not been typified (Jarvis 2007: 402). This paper proposes the designation of a lectotype for this Linnaean name, based on the analysis of the protologue and original material.

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Sobre el complejo taxonómico de Teucrium gnaphalodes l'Hér. (sect. Polium, Lamiaceae) y algunos de los híbridos en los que interviene

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