Congresos 2011 y anteriores

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Activity of gullies during the Holocene in the Ebro valley
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Peña, Julio; Constante, A.; Chueca, J.; Echeverría Arnedo, María Teresa; Julián, A.; Longares, L.A.
The use of detailed geomorphology for the study of the Upper Holocene and the application of geoarchaeology and radiometric datings make it possible to get important results on the recent stages of valley bottom shaping. The timing of the aggradation and degradation phases shows the activity of the processes over the last 8000 years and the decisive influence of the Holocene evolution on present landscapes. The reasons for this phase alternation are anthropoclimatic, as Jordá and Vaudour (1980), Bintliff (1981, 1982), Gutiérrez and Peña (1998) and Peña (1996), Peña et al. (2000, 2004) recognize in different sectors of the Mediterranean basin. The gullies formation and activity from the late Roman Period has progressed by means of a regressive activity of the headwaters, although the excavation process has been temporarily interrupted by new fillings.
Open Access
Agaricus devoniensis complex comprises a group of heterothallic isolates constituting a basis for breeding
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Callac, P.; Spataro, C.; Lataillade, E.; Blasi, P.; Guinberteau, J.
A recent phylogenetic reconstruction of Agaricus section Duploannulati revealed that A. devoniensis and A. subfloccosus are two complexes of species close to A. bisporus. The A. subfloccosus complex comprises two homothallic entities, while the A. devoniensis complex was never studied until now. A sample of 26 isolates, some being unreliably determined, were examined to (i) confirm their identity using a PCR-RFLP marker revealing a characteristic A. devoniensis ITS polymorphism, and (ii) for their ability to fruit in standard conditions used for A. bisporus cultivation. Twenty one isolates were confirmed as A. devoniensis, and only two collections from USA were unable to fruit. The five remaining isolates were excluded from the complex and were unable to fruit; their ITS1+2 regions were sequenced and alignments indicated that four of them were similar to A. campestris and that one belonged to a new entity close to A. bitorquis and A. cappellianus. For the 19 fructifying isolates of the complex, we attempted intrastock and interstock mating tests with single spore isolates: for three isolates, we did not get spore germination; and for seven isolates, we observed partial to complete intersterility between strains. The nine remaining isolates exhibited a unifactorial system of sexual incompatibility for which eight different mating type alleles were detected. Within this group, the heterothallic and presumably interfertile isolates differed in their origin (Greece, France), their habitat (dune, coniferous trees), and their morphology (mean spore length: 5.6 to 6.6 μm); they constitute a diversified genetic basis usable to select smooth white and attractive cultivars for this tasteful edible and cultivable species.
Open Access
Agricultural land use, piping and gullies activity in the Huelva lower valley (Saragossa, Spain)
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Echeverría Arnedo, María Teresa; Ibarra, P.; Pérez Cabello, F.
The variations in the total amount of surface used for arable crops both for dry farming and fallow land, with regard to the different “agricultural policies”, have modified the natural dynamics of some processes such as piping and gullies activity in the Huerva lower valley (Saragossa) over the last 50 years.
Open Access
Alluvial gully erosion: a landscape denudation process in Northern Australia
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Brooks, A.P.; Shellberg, J.G.; Spencer, J.; Knight, J.
Recent aerial reconnaissance surveys and subsequent remote sensing mapping of Australia’s tropical rivers identified alluvial gully erosion as a key sediment source (Brooks et al. 2007; Knight et al. 2007). Gully erosion is found to varying degrees within alluvial river types in northern Australia, but it is most extensive on alluvial plains of the larger rivers like the Mitchell, Leichhardt and Nicholson Rivers, draining into the Gulf of Carpentaria. However, very little is currently known about gully erosion processes in these landscapes.
Open Access
Analysis of water erosion using GIS and remote sensing for the management of protected natural environments in the south of the province of Salamanca (Spain)
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Martínez Graña, A.M.; Goy, J.L.; Zazo, C.
The soil is a natural resource that must be conserved in protected natural areas since it is one of the determinant physical supports in territorial planning because it governs its different uses. Accordingly, specific studies must be carried out aimed at estimating soil losses at individual project level and at the general level of Natural Environments in order to establish methodologies for the control and ordering of activities, above all in protected environments whose focus is on sustainable activities. The basic objective should delimit different erosive forms where best it reflects the risk of water erosion (gullies, rills) and the degree (weak, light, important, and burden) and the processes induced (slides, scarp, remontant erosion...) in addition the evolution with time.
Open Access
AnnAGNPS ephemeral gully erosion simulation technology
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Bingner, R.L.; Theurer, F.D.; Gordon, L.M.; Bennett, S.J.; Parker, C.; Thorne, C.; Alonso, C.V.
Tillage-induced ephemeral gully erosion has been shown to be a significant and sometimes dominant source of sediment within a watershed. An approach has been developed within AnnAGNPS to assess the impact of conservation practices on ephemeral gully erosion as well as sheet and rill erosion. Conservation management treatments should include targeting practices specific for ephemeral gullies differently than for sheet and rill erosion. Within watersheds, gullies are becoming the dominate source of cropland erosion unless preventative conservation practices are installed.
Open Access
Anticancer activity of polysaccharides produced by Pleurotus ostreatus in submerged culture
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Daba, A.; El Demellawy, M.; El Eshasy, H.
It has been known for many years that some compounds produced by edible mushrooms encompass anticancer activities. Most of production methods were based on cultivation of mushroom in solid medium. In the present study Pleurotus ostreatus mycelia were grown in submerged culture. The cultivation of fungal cells in submerged culture resulted in higher growth rate with better control of production process. The bioactive polysaccharides (both intracellular and extracellular) were extracted from culture by solvent repeated precipitation. The polysaccharide structure was determined by examining NMR, IR spectra and the primary structure of the polysaccharide was mainly glucan. The 13C NMR spectral pattern indicated the polysaccharides are highly branched with mainly 1→3 and 1→6 linkage. The results of in vitro anti cancer studies demonstrate that this type of polysaccharides possesses anticancer activity against human oesophageal cancer cell line. Moreover, in the course of in vitro studies, mushroom polysaccharides showed anti-tumour activity and also considered to be biological response modifier because of their mechanism of action through stimulation of the immune system. The polysaccharide activity is especially beneficial in clinics when used as an adjuvant with chemotherapy to decrease its side effect. This work describes production process of anti cancer compound( s) by mushrooms and suitable for pharmaceutical industries.
Open Access
Assessment of gully erosion using photogrammetric techniques. A case study of upper Mbuluzi river, Swaziland
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Pelacani, S.; Märker, M.; Rodolfi, G.
Swaziland is severely affected by gully erosion contributing to a sediment budget up to 250,000 m3 y-1 (WMS Associates, 1988). This type is more important than inter-rill and rill erosion. Severe gully erosion is mainly in the Middleveld especially on communal land highly populated (43.65 inhabitants km-2) and with high livestock concentrations. Here, the calculated carrying capacities are 0.27 LSU ha-1 (Livestock Units) vs. stocking rates 0.87 LSU ha-1. In general, to assess gully erosion, numerous investigators have made use of aerial photos and GIS to predict the morphometric conditions that favoured gulling (Nachtergaele and Poesen, 1999). In Swaziland, from 1947 to 1987, the WMS Associates (1988) established gully erosion rates from aerial stereo photos. Subsequently, Mushala et al., 1994 analyzed the gullies distribution and their relationship to lithology and land tenure. In the present research long terms rates of gully erosion have been measured by aerial photos taken from 1947 to 1996. Particular attention was focused on two dendritic gully systems. One of them is dynamically evolving, whereas the other one is in a static phase (Sidorchuk, 1999). The objectives of this research were to calculate the historical development of the morphology of gully as input data to the gully erosion model (Sidorchuk et al., 2001) and to predict hillslope area susceptible to gulling. A High Digital Terrain Models (HDTMs) with 1-m resolution were devised for this purpose.
Open Access
Atypical laccases from the white-rot fungus Pleurotus ostreatus and their application for the treatment of industrial coloured effluents
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Festa, Giovanna; Giardina, Paola; Faraco, Vicenza; Piscitelli, Alessandra; Sannia, Giovanni
White-rot fungi are the most efficient decomposers of lignocellulose because of their capability to synthesize the relevant hydrolytic (cellulases and hemicellulases) and oxidative (laccases, lignin-peroxidases and Mn-peroxidases) extracellular enzymes required to degrade the major components of substrates (cellulose, hemicellulose, and lignin) into low-molecular-weight compounds that can be assimilated in fungal nutrition [1]. Recently, extensive research on these fungi has been conducted with the aim of isolating new organisms able to secrete new enzymes with capability to be used in industrial applications, such as bioremediation of polluted soils and industrial waste-waters, biobleaching and biopulping in pulp and paper industries, textile and food industries, etc. Fungal laccases (benzenediol: oxygen oxidoreductases; EC1.10.3.2) are ligninolytic enzymes that have been isolated from various fungi [2]. They belong to the class of the blue oxidases containing 4 copper atoms/molecule distributed in three different copper binding sites [3, 4]. The type-1 site is responsible for the intense blue colour of the enzyme due to a maximum absorbance at 605 nm; the type-2 site does not exhibit signals in the visible absorbance spectrum; and the type-3 site incorporates two copper centres and is responsible for a band near 330 nm. All these copper ions are involved in the catalytic mechanism. Laccases reduce oxygen to water and simultaneously perform a one electron oxidation of aromatic substrates (polyphenols, methoxysubstituted monophenols, aromatic amines, etc.). These enzymes are present in multiple isoforms, depending on the fungal species and environmental growth conditions [5, 6].
Open Access
Biochemistry of volatile compounds synthesis in Agaricus bisporus
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Combet, E.; Henderson, J.; Eastwood, D.C.; Griffiths, G.; Burton, K.S.
Agaricus bisporus unique flavour is due to the release of a set of eight-carbon volatile compounds, which biosynthetic pathway has not been elucidated yet, despite of the numerous implications of those volatile compounds. Beside their influence on crop quality, they are also important for insect perception and play a part in triggering the switch from vegetative to reproductive growth in mushrooms. 8-carbon volatiles are derived from the oxygenation and the cleavage of the polyunsaturated fatty acid linoleic acid. This reaction has similarities to the plant system, but also major differences. Examination of the enzymic mechanisms and the fatty acid chemistry suggested that the enzyme involved in the oxygenation step could be a lipoxygenase (as found in plants) or a heme-dioxygenase, similar to the recently isolated linoleate diol synthase from Gaeumannomyces graminis. In order to characterise the biochemical pathway leading to eight-carbon volatile production, we investigated fatty acid and lipids distribution in Agaricus bisporus, as well as hydroperoxide and volatile compounds levels. In parallel, we searched for candidate genes susceptible to encode the enzyme responsible for this novel oxidation route in fungi. The combination of analytical methods, such as GC-MS, with a molecular approach based on degenerate PCR and library screening provided us with a broad range of results. These results establish the relation between fatty acids and volatile compounds and enabled us to gain a better understanding of mushroom volatiles biosynthesis and lipid metabolism.
Open Access
Causes of gully erosion in arid ecosystem: case study southern part of I.R. Iran
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Soufi, M.
This research demonstrated that the I.R. region is prone to gully erosion. The study area had limited gully erosion four decades ago. With accelerating urban development during the past, two to three decades, areas of gully erosion increased. Comparison of gully advancement showed that the area of gully erosion increased 4 times in four decades before. Gullies are located around urban areas with more deteriorated cropland and roads. Statistical analysis revealed that area of gully erosion could be attributed to the area of bareland and road length. The overall the impact of bareland area is more significant than road length in study watersheds, although their contribution in individual site is completely different.
Open Access
Cell wall-associated redox enzymes in white rot fungi
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Dwivedi, R.C.; Zomorrodi, M.; Kües, Ursula; Majcherczyk, A.
Many enzymes of white rot fungi involved in wood degradation belong to the class of redox enzymes. The most important are laccase (copper-containing polyphenol oxidase), lignin peroxidase, manganese- dependent peroxidase and manganese-independent peroxidase. However, the role of these enzymes in wood degradation remains unclear and complex redox processes or unknown redox enzymes also may contribute to this process. Several oxidative enzymes secreted by white rot fungi into the environment have been studied in the past, but little attention has been paid to the cell wall-associated redox enzymes. Cell wall-associated laccase activity in the purified cell walls of copper induced cultures of Trametes versicolor has been found. Laccases have been extracted by establishing new methods for cell wall purification and for protein release from the cell walls of basidiomycetes.
Open Access
Characterisation of Agaricus bisporus response genes to Verticillium fungicola infection
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Costa, A.; Thomas, D.J.I.; Bailey, A.; Foster, G.D.; Challen, M.P.; Mills, P.R.
The mycoparasite Verticillium fungicola is a persistent threat to the cultivation of the mushroom Agaricus bisporus. Mushroom “dry bubble” is characterised by an undifferentiated mass of cells and can result in major crop losses. During the establishment of “dry bubble” substantial changes occur in the biochemistry and physiology of both partners. To enable new insights to be made into the molecular events underlying the disease, work is in progress to identify genes expressed during pathogen infection. Subtractive Suppressive Hybridisation (SSH) has enabled recovery of 65 expressed sequenced tags (ESTs) differentially expressed during infection. After database searches 27 of the genes were identified as most likely from V. fungicola, 25 from A. bisporus and 13 unknown. Bioinformatic analysis suggested that the response genes identified were involved in a range of biological functions that included stress, signalling, protein synthesis and cell wall structure and function. Specific full-length genes will be recovered using cDNA library constructed from lesions of A. bisporus infected with V. fungicola, enabling silencing approaches to be used to further investigate the role of the identified genes in disease. An alternative higher-throughput method of gene function analysis, RNA interference (RNAi) using A. bisporus model genes (URA3, CBX), is also being developed. Silencing constructs expressing RNAi hairpin were transformed into A. bisporus using Agrobacterium tumefaciens and hygromycin resistance. Screening of the transformants by PCR confirmed integration of the silencing construct in 24 transformants. RT-PCR is being used to confirm transcription of the RNAi hairpin. Quantitative PCR will be used to analyse levels of target gene transcripts post RNAi transformation. The role of A. bisporus genes identified, in the infection process, will be determined through infection trails with A. bisporus silenced lines.
Open Access
A comparison of anthropogenic and long-term soil erosion on banks peninsula using 137Cs and kawakawa tephra
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Lutter, F.S.; Almond, P.C.; Florineth, F.
The task of this study is to assess the severity of anthropogenically induced soil erosion on a loess-mantled hillslope on the foothills of Banks Peninsula, South Island, New Zealand. The analysis is restricted to a slope segment representative for the soil creep-type processes that dominate on convex soil-mantled hillslopes which satisfy the assumptions of the soil erosion measurement techniques employed.
Open Access
Comparison of historical evolution of gully networks on both Slovak and Moravian forelands of the white Carpathians
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Stankoviansky, M.; Létal, A.; Damankosová, Z.
The main objective of the contribution is to present the preliminary results of comparison of historical evolution of gully networks in both Slovak and Moravian forelands of the White Carpathians. This geomorphic unit represents the flysch mountain range situated in the boundary zone of Slovakia and the Czech Republic, reaching the elevation 970 m. The Slovak foreland of the White Carpathians, i.e. the Myjava Hill Land, belongs among those areas in Slovakia that were the most affected by disastrous gullying in the past. This fact was one of the main reasons to choose precisely this area for detailed investigation of historical gullies, lasting at the moment approximately one decade. The study of the Moravian foreland of the White Carpathians, i.e. Hluk Hill Land, started in 2006. Its first goal was to find out if the density of gully network on the Moravian side is comparable with that at the Slovak side. Beside the density of gully networks also the age of gullies and causes of their formation on both sides of the frontier were subjects of this comparison. Comparison of gullies on both forelands of the White Carpathians is introduced in the context of the review of the research dealing with the historical evolution of gullies in Slovakia and Czech Republic.
Open Access
Computational prediction of protein-coding gene and annotation of DNA sequences with agronomic interest in Pleurotus ostreatus (Oyster Mushroom)
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Palma Dovis, Leopoldo; Peñas Parrila, María Manuela; Ramírez Nasto, Lucía; Pisabarro de Lucas, Gerardo; Producción Agraria; Nekazaritza Ekoizpena
Pleurotus ostreatus, commonly known as oyster mushroom, is a commercially important edible fungus with interesting biotechnological properties. Quantitative trait loci (QTL) analyses are rare in fungi and little is known about their number, position, and genetic structure. Previous studies of our group have allowed the construction of a genetic linkage map of P. ostreatus var. florida, which has provided the basis for performing an efficient QTL analysis. In fact, there is a region of the chromosome VII of P. ostreatus where the most QTLs related to the production and precocity characters have been mapped. These quantitative traits are presumably under the control of a polygenic genetic system and could be associated with some chromosomal regions. The hypothesis of this work is that there is a region in the chromosome VII of protoclon PC15 (monokaryotic parental of the N001 dikaryotic strain) where exist genes which are responsible for the QTLs mentioned above. In order to test this hypothesis, we are developing a molecular QTL analysis through the sequencing of a region with an approximated size of 320 Kbp in chromosome VII (protoclon PC15). For this purpose, a BAC genomic library was constructed and two BAC clones spanning the region of interest are being sequenced. To carry out an efficient computational prediction of protein-coding genes and its annotation on the partial sequences obtained up to date, we have used different Internet resources such as BLASTx, BLASTp, BLASTn, and FGENESH trained on some basidiomycetes genomic data like Phanerochaete chrysosporium and Cryptococcus neoformans (SoftBerry). To our knowledge, this is the firs molecular QTL analysis performed on this edible mushroom.
Open Access
Concentrated flow erodibility of loess-derived topsoils: the impact of rainfall-induced consolidation and sealing
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2007) Knapen, A.; Poesen, J.; Baets, S. de
This study investigates the impact of rainfall-induced soil consolidation and soil surface sealing processes over time after tillage on soil erosion during concentrated flow. The soil erodibility (Kc) and critical flow shear stress (τcr) were examined for identical, artificially created soil samples under simulated rainfall. As these rainfall-induced soil structural changes are inseparably related to soil moisture variations, the effects are evaluated for different soil moisture conditions.
Open Access
Copper in fruiting body development of Coprinus cinereus
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Navarro González, Mónica; Kilaru, S.; Majcherczyk, A.; Kües, Ursula
The model homobasidiomycete Coprinopsis cinerea grows best at 37°C, but, normally, it produces fruiting bodies only at moderate temperatures around 25-28°C. Light is needed to induce fruiting and also for fruiting body maturation. Cultures kept after fruiting induction predominantly in the dark form structures with an extended stipe and an underdeveloped cap (so-called “etiolated stipes”). In a day/night rhythm, caps develop further, basidia are formed, in which karyogamy and meiosis occurs and of which the basidiospores bud off. Besides light, fruiting body development in basidiomycetes has been repeatedly linked to enzymes belonging to the group of phenoloxidases, in particular the multi-copper containing laccases. However, their roles in fruiting remain unclear. In attempts to induce laccase production in liquid standing cultures at 37°C, to our surprise we found unusual inititation of fruiting body development. However, the abundantly formed primordia did never develop into mature fruiting bodies but into large-sized etiolated stipes, both in dark and in light. Laccase under these conditions was not detected in the medium but bound to the fruiting initiating mycelium. Moreover, enzyme production and etiolated stipe formation correlated with an increase from pH 5.5 to a slightly alkaline pH. Ammonium was found to be produced and nitrate reductase activity has enzymatically been shown. Under normal fruiting conditions, addition of copper to cultures enhances fruiting initiation in time and number. To further unravel the potential involvement of laccases in fruiting as well as of proteins influencing ammonia secretion, we are studying expression of corresponding genes during vegetative growth and fruiting body development. Work in our laboratory is supported by DBU (Deutsche Bundesstiftung Umwelt). MNG holds a CONACYT (Mexico) PhD studentship.
Open Access
The Coprinus cinereus genome project
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Gathman, A.; Lilly, W.; Stajich, Jason E.; Carlson, M.; Murphy, B.; Smith, A.; Fargo, D.; Dietrich, F.; Pukkila, P.J.
Coprinus cinereus is an increasingly attractive basidiomycete model system. Its genome has been sequenced and is publicly available; it is readily cultured in the laboratory on defined media, it has highly synchronous meiosis, and numerous laboratory techniques have been adapted for use with it. The 10X shotgun sequence released by the Whitehead Institute comprises 36 Mb of the 37 Mb of the genome, which have been assembled into 106 supercontigs containing 431 contigs. cDNA libraries have been constructed from two meiotic stages, and 1432 candidate genes have been identified from them. Another set of cDNA libraries has been constructed from vegetative Coprinus cinereus Okayama 7 grown under different environmental conditions, including heat shock, rapamycin treatment, minimal medium, rich medium, and complex carbon and nitrogen sources. 5000 ESTs are being sequenced from these libraries. The EST sequences have been aligned with the genomic sequence, as have known C. cinereus genes from GenBank. Data from known ascomycete gene sequences have been used to train SNAP software to predict a total of 11,340 genes from the remainder of the genome. BlastX and Pfam have been used to assign tentative functions to predicted genes as well as ESTs. tRNA genes have also been identified in the genome. All genomic information is available online via our Gbrowse server.
Open Access
Development of a sporeless strain of oyster mushroom (Pleurotus ostreatus)
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Baars, Johan; Sonnenberg, Anton S.M.; Hendrickx, Patrick
The enormous amounts of spores produced by oyster mushroom (Pleurotus ostreatus) cause lung-related health problems among employees working in oyster mushroom cultivation. If sporeless varieties are used for large-scale cultivation, these lung problems can be avoided. For development of a commercially attractive strain of sporeless oyster mushroom, strain ATCC 58937, a sporeless strain of oyster mushroom was used as a donor of the trait. Microscopic analysis of basidia showed that meiosis was aborted at an early stage. Both nuclear types that constitute strain ATCC 58937 could be retrieved by protoplasting. Protoplasting commercial strain HK35 yielded only one of its nuclear types. Crosses between the ATCC nuclear types and the HK35 nuclear types (either directly or using the Buller phenomenon) yielded normal sporulating strains, indicating that sporelessness was caused by a recessive trait. Among the offspring of crosses between the ATCC nuclear types and the HK35 nuclear types the sporeless trait segregated in a 1 to 1 ratio. The sporeless trait could be mapped and strongly linked genomic markers were developed. The breeding strategy was to successfully introduce sporelessness into both nuclear types of a commercial variety, to achieve a sporeless variety. In a first cross between a sporeless culture and a commercial strain, not only sporelessness was transferred to the commercial variety. Therefore, repeatedly backcrossing the progeny of the first cross with the commercial variety is used to try to restore the original genetic material from the commercial strain as much as possible. Performance of a number of “prototypes” of a sporeless oyster mushroom was tested on commercial mushrooms farms and proved to be satisfactory.