24 research outputs found
Fray Luis de Granada, teólogo
Tras una introducción histórica
en la que se describe el contexto espiritual
y teológico en que se mueve
Fray Luis de Granada, el A. desarrolla
su visión en torno al quehacer teológico
y a las dos formas principales de hacer
teología (teología escolástica y teología
mística). En el contexto histórico,
Huerga destaca las relaciones de Fray
Luis con el Colegio de San Gregorio de
Valladolid y el juicio que su figura de
teólogo le merece a Gonzalo de Arriaga.
En este contexto, se destaca la acertada
visión que Cano tiene de la posición
de Fray Luis ante la teología, y el
desacertado juicio que el mismo Cano
emite en torno a esta posición. En efecto,
según Cano, la Iglesia podía reprender
gravemente a Fray Luis el hecho de
«que pretendió hacer contemplativos y
perfectos a todos, y enseñar al pueblo
en castellano» y, por lo tanto, hacer la
teología asequible a todos. Sin embargo,
aquí radica justamente la grandeza
de Fray Luis: haber sabido destacar el carácter sapiencial de la teología y su
universalidad, haber distinguido coherentemente
entre teología especulativa
o escolástica y teología afectiva o mística,
y haber sabido sintetizar los rasgos
esenciales de ambas, poniendo de relieve
que el principal maestro de esta última
es el Espíritu Santo
Failure under stress of grapevine wood: The effects of the cerambycid xylotrechus arvicola on the biomechanics properties of vitis vinifera
Xylotrechus arvicola is an insect pest on Vitis vinifera in the main wine-producing regions of Spain. X. arvicola larvae bore inside grapevine wood, which cause structural damages in the plants´ biomechanical properties. Grapevine wood affected and unaffected by larvae, were collected from vineyards. Compression and flexural tests were used to quantify biomechanical wood properties. Affected wood broke more quickly and endured a lower supported force than unaffected wood in both varieties and moisture states. Tempranillo was the most resistant variety on trunks, while Cabernet-Sauvignon was the most resistant variety on branches, where all infested varieties showed a lower rate of bending. Grapevine wood affected by X. arvicola larvae shows an important decrease in its resistance in both moisture states - dry and wet wood - and it is observed due to the faster break in time and a lower supported force. These damages give the affected wood greater sensitivity to external mechanical factors in the vineyards, such as strong winds, harvest weight and the vibration exerted by harvesting machines. The aspect of stress-time curves in all cases follow similar patterns, so in future studies might be possible to stablish relationships between both wet and dry samples and different infestation levels
Failure under stress of grapevine wood: The effects of the cerambycid Xylotrechus arvicola on the biomechanics properties of Vitis vinifera
[EN] Xylotrechus arvicola is an insect pest on Vitis vinifera in the main wine-producing regions of Spain. X. arvicola larvae bore inside grapevine wood, which cause structural damages in the plants´ biomechanical properties. Grapevine wood affected and unaffected by larvae, were collected from vineyards. Compression and flexural tests were used to quantify biomechanical wood properties. Affected wood broke more quickly and endured a lower supported force than unaffected wood in both varieties and moisture states. Tempranillo was the most resistant variety on trunks, while Cabernet-Sauvignon was the most resistant variety on branches, where all infested varieties showed a lower rate of bending. Grapevine wood affected by X. arvicola larvae shows an important decrease in its resistance in both moisture states - dry and wet wood - and it is observed due to the faster break in time and a lower supported force. These damages give the affected wood greater sensitivity to external mechanical factors in the vineyards, such as strong winds, harvest weight and the vibration exerted by harvesting machines. The aspect of stress-time curves in all cases follow similar patterns, so in future studies might be possible to stablish relationships between both wet and dry samples and different infestation levels
The Influence of Temperature on the Growth, Sporulation, Colonization, and Survival of Trichoderma spp. in Grapevine Pruning Wounds
[EN] Trichoderma is a genus of fungi used for the biological control of plant diseases and a large
number of its bio-formulates are available in the market. However, its efficacy under field conditions
remains unclear, especially for the protection of grapevine plants against Grapevine Trunk Diseases
(GTDs). These diseases are caused by a complex of fungal pathogens whose main point of entrance
into the affected plants is through pruning wounds. In this research, different Trichoderma native
strains have been evaluated according to their ability to grow at different temperatures and their
capacity to colonize pruning wounds in adverse climatic conditions. Strains from section Trichoderma
have adapted to cooler conditions. On the other hand, strains from clade Harzianum/Virens grow
at higher temperatures. However, differences can also be found between strains inside the same
clade/section. Native strains were able to colonize more than 70% of vine pruning wounds in winter
conditions. The Trichoderma strain T154 showed a significantly higher re-isolation degree from vine
plants and its concentration was optimized for spraying onto vine plants. In conclusion, Trichoderma
native strains are better adapted to survive in a changing environment, and they could give better
protection to grapevine plants in co-evolution with each specific vineyardSIThis research was supported by project GLOBALVITI ‘Solución global para mejorar la This research was funded by the Centro para el Desarrollo Tecnológico Industrial–CDTI—(Madrid, Spain) for the project GLOBALVITI project (CIEN Program) IDI-20160746, and the project LowpHwine (CIEN Program) IDI ‘Estudio de nuevos factores relacionados con el suelo, la planta y la microbiota enológica que influyen en el equilibrio de la acidez de los vinos y en su garantía de calidad y estabilidad en climas cálidos’—and the grant awarded to GC-H comes from the Ministry of Education, Culture, and Sport (SPAIN), grant number (FPU15/04681) and Bodega Pago de Carraovejas S.L.U. We thank technical assistance of Javier Saiz Gade
Vineyard Management and Physicochemical Parameters of Soil Affect Native Trichoderma Populations, Sources of Biocontrol Agents against Phaeoacremonium minimum
[EN] Native strains of Trichoderma in vineyard soil represent an opportunity for reducing the
incidence of grapevine trunk diseases (GTDs) in vineyards. Moreover, its relationship with the
environment (physicochemical soil characteristics and farming management practices) remains
unclear. In the current study, a survey was carried out on farming management used by viticulturists,
and soil samples were studied to analyze their physicochemical properties and to isolate
Trichoderma strains. Later, statistical analyses were performed to identify possible correlations between
Trichoderma populations, soil management and soil characteristics. In addition, in vitro tests,
including antibiosis and mycoparasitism, were performed to select those Trichoderma strains able to
antagonize Phaeoacremonium minimum. In this study a positive correlation was found between the
iron content and pH in the soil, and a lower pH increases Trichoderma populations in soils. Vineyard
management also affects Trichoderma populations in the soil, negatively in the case of fertilization
and tillage and positively in the case of herbicide spraying. Two Trichoderma native strains were
selected as potential biocontrol agents (Trichoderma gamsii T065 and Trichoderma harzianum T087)
using antibiosis and mycoparasitism as mechanisms of action. These results led to the conclusion
that native Trichoderma strains hold great potential as biological control agents and as producers of
secondary metabolites.SIThis research was funded by project GLOBALVITI ‘Solución global para mejorar la’ Centro para el Desarrollo Tecnológico Industrial–CDTI—(Madrid, Spain) Project, GLOBALVITI project (CIEN Program) IDI-20160746, the project LowpHwine (CIEN Program) IDI ‘Estudio de nuevos factores relacionados con el suelo, la planta y la microbiota enológica que influyen en el equilibrio de la acidez de los vinos y en su garantía de calidad y estabilidad en climas cálidos’ and Bodega Pago de Carraovejas S.L.U. Thanks to all the wineries and viticulturists who kindly let us sample their vineyards. Thanks also to the research staff of the GUIIAS group for their technical support
Influence of Physicochemical Characteristics of Bean Crop Soil in Trichoderma spp. Development
[EN] Spain has ranked 6th on the harvested bean area and 8th in bean production in the European Union (EU). The soils of this area have mixed silt loam and sandy loam texture, with moderate clay content, neutral or acidic pH, rich in organic matter and low carbonate levels, providing beans with high water absorption capacity and better organoleptic qualities after cooking. Similar to other crops, it is attacked by some phytopathogens. Hitherto, chemical methods have been used to control these organisms. However, with the Reform of the Community Agrarian Policy in the EU, the number of authorized plant protection products has been reduced to prevail food security, as well as to be sustainable in the long term, giving priority to the non-chemical methods that use biological agents, such as Trichoderma. This study aimed to investigate the relative importance of various crop soil parameters in the adaptation of Trichoderma spp. autoclaved soils (AS) and natural soils (NS) from the Protected Geographical Indication (PGI) “Alubia La Bañeza—León” that were inoculated with Trichoderma velutinum T029 and T. harzianum T059 and incubated in a culture chamber at 25◦C for 15 days. Their development was determined by quantitative PCR. Twelve soil samples were selected and analyzed from the productive zones of Astorga, La Bañeza, La Cabrera, Esla-Campos and Páramo. Their physicochemical characteristics were different by zone, as the texture of soils ranged between sandy loam and silt loam and the pH between strongly acid and slightly alkaline, as well as the organic matter (OM) concentration between low and remarkably high. Total C and N concentrations and their ratio were between medium and high in most of the soils and the rest of the micronutrients had an acceptable concentration except for Paramo’s soil. Both Trichoderma species developed better in AS than in NS, T. velutinum T029 grew better with high levels of OM, total C, ratio C:N, P, K, Fe, and Zn than T. harzianum T059 in clay soils, with the highest values of cation exchange capacity (CEC), pH, Ca, Mg and Mn. These effects were validated by Canonical Correlation Analysis (CCA), texture, particularly clay concentration, OM, electrical conductivity (EC), and pH (physical parameters) and B and Cu (soil elements) are the main factors explaining the influence in the Trichoderma development. OM, EC, C:N ratio and Cu are the main soil characteristics that influence in T. velutinum T029 development and pH in the development of T. harzianum T059.SIThis research was funded by Junta de Castilla y León, Consejería de Educación for the project “Application of Trichoderma strains in sustainable quality bean production” (LE251P18
Effect of Farnesol in Trichoderma Physiology and in Fungal–Plant Interaction
[EN] Farnesol is an isoprenoid intermediate in the mevalonate (MVA) pathway and is produced by the dephosphorylation of farnesyl diphosphate. Farnesol plays a central role in cell growth and differentiation, controls production of ubiquinone and ergosterol, and participates in the regulation of filamentation and biofilm formation. Despite these important functions, studies of farnesol in filamentous fungi are limited, and information on its effects on antifungal and/or biocontrol activity is scarce. In the present article, we identified the Trichoderma harzianum gene dpp1, encoding a diacylglycerol pyrophosphatase that catalyzes production of farnesol from farnesol diphosphate. We analyzed the function of dpp1 to address the importance of farnesol in Trichoderma physiology and ecology. Overexpression of dpp1 in T. harzianum caused an expected increase in farnesol production as well as a marked change in squalene and ergosterol levels, but overexpression did not affect antifungal activity. In interaction with plants, a dpp1-overexpressing transformant acted as a sensitizing agent in that it up-regulated expression of plant defense salicylate-related genes in the presence of a fungal plant pathogen. In addition, toxicity of farnesol on Trichoderma and plants was examined. Finally, a phylogenetic study of dpp1 was performed to understand its evolutionary history as a primary metabolite gene. This article represents a step forward in the acquisition of knowledge on the role of farnesol in fungal physiology and in fungus-environment interactionsSIThis research was funded by the Spanish I+D+i Grants AGL2012-40041-C02-02, AGL2015-70671-C2-2-R, RTI2018-099600-B-I00 and PID2021-123874OB-I00, financed by the MCIN/ AEI/10.13039/501100011033. GC-H was awarded with a Grant from the Ministry of Education, Culture, and Sport (Spain) (Grant number FPU15/04681). NM-R was awarded with a Grant from the Junta de Castilla y León (Spain) (ORDEN EDU/875/2021, 13 July 2021
Spores of Trichoderma Strains over P. vulgaris Beans: Direct Effect on Insect Attacks and Indirect Effect on Agronomic Parameters
[EN] Acanthoscelides obtectus is an insect pest that attacks wild and cultivated common beans (Phaseolus vulgaris L). Four Trichoderma strains, the T. arundinaceum IBT 40837 wild-type strain (=Ta37), a producer of trichothecene harzianum A (HA), two transformants of T. arundinaceum strain, Ta37-17.139 (=Δtri17) and Ta37-23.74 (=Δtri23), and the T. brevicompactum IBT 40841 wild-type strain (=Tb41), which produces the trichothecene trichodermin, were assessed to establish their direct effect on insect attacks and their indirect effect on the plants grown from the beans treated with those fungal strains and exposed to insect attacks. Treatments of bean seeds with different Trichoderma strains led to different survival rates in the insects, and the Tb41 strain caused the lowest survival rate of all. An 86.10% of the insect cadavers (in contact with Δtri23) showed growth of this strain. This was the treatment that attracted the greatest number of insects. The daily emergence was reduced in beans treated with the Ta37, Tb41, and Δtri17 strains. The undamaged beans treated with Ta37 and Δtri23 showed a high capacity of germination (80.00% and 75.00%, respectively), whereas the Δtri17 and Tb41 treatments increased the capacity of germination in the damaged beans (66.67%). The undamaged beans treated with Δtri23 had the greatest dry weights for the aerial part (4.22 g) and root system in the plants (0.62 g). More studies on the mechanisms of insect control, plant growth promotion, and trichodermol and trichodermin production by Δtri23 and Tb41, respectively, should be explored in order to commercialize these fungal species on a large scale.SIWe would like to thank the Ministry of Science, Innovation, and Universities (Spain) (Resolution of 27 July 2018, BOE No.184, of July 31) for giving a grant to Álvaro Rodríguez González (PTA2017-14403-I) through the program Technical Support Staff (Call 2017). All authors included in this section have consented to the acknowledgement
Effects of trichothecene production by Trichoderma arundinaceum isolates from bean-field soils on the defense response, growth and development of bean plants (Phaseolus vulgaris)
[EN] The trichothecene toxin-producing fungus Trichoderma arundinaceum has potential as a biological control agent. However, most biocontrol studies have focused only on one strain, IBT 40837. In the current study, three Trichoderma isolates recovered from bean-field soils produced the trichothecene harzianum A (HA) and trichodermol, the latter being an intermediate in the HA biosynthesis. Based on phylogenetic analysis, the three isolates were assigned to the species T. arundinaceum. Their genome sequences had a high degree of similarity to the reference IBT 40837 strain, in terms of total genome size, number of predicted genes, and diversity of putative secondary metabolite biosynthetic gene clusters. HA production by these bean-field isolates conferred significant in vitro antifungal activity against Rhizoctonia solani and Sclerotinia sclerotiorum, which are some of the most important bean pathogens. Furthermore, the bean-field isolates stimulated germination of bean seeds and subsequent growth of above ground parts of the bean plant. Transcriptomic analysis of bean plants inoculated with these T. arundinaceum bean-field soil isolates indicated that HA production significantly affected expression of plant defense-related genes; this effect was particularly significant in the expression of chitinase-encoding genes. Together, these results indicate that Trichoderma species producing non-phytotoxic trichothecenes can induce defenses in plants without negatively affecting germination and developmentSIThis work is a part of the Spanish I+D+i Grants RTI2018-099600-B-I00 and PID2021-123874OB-I00, financed by the MCIN/ AEI/10.13039/501100011033. GC-H was awarded with a Grant from the Ministry of Education, Culture, and Sport (Spain) (Grant number FPU15/04681). NM-R was awarded with a Grant from the Junta de Castilla y León (Spain) (ORDEN EDU/875/2021, July 13th, 2021
The Raman laser spectrometer ExoMars simulator (RLS Sim): A heavy‐duty Raman tool for ground testing on ExoMars
Producción CientíficaThe Raman laser spectrometer (RLS) instrument onboard the Rosalind Franklin rover of the ExoMars 2022 mission will analyze powdered samples on Mars to search for traces of life. To prepare for the mission, the RLS scientific team has developed the RLS ExoMars Simulator (RLS Sim), a flexible model of RLS that operates similarly to the actual instrument, both in laboratory and field conditions, while also emulating the rover operational constraints in terms of sample distribution that are relevant to the Raman analysis. This system can operate autonomously to perform RLS-representative analysis in one or several samples, making it very useful to perform heavy experimental tasks that would otherwise be impossible using a flight-representative model of the instrument. In this work, we introduce the current configuration of the RLS Sim that has incorporated new hardware elements such as the RAman Demonstrator 1 (RAD1) spectrometer with the objective of approaching its performance to that of the actual RLS instrument. To evaluate the scientific capability of the RLS Sim, we have compared it with a replica model of RLS, the RLS Flight Spare (FS). Several acquisition aspects have been evaluated based on the analysis of select samples, assessing the performance in terms of spectral range and resolution and also studying several issues related to the evolution of signal-to-noise ratio (SNR) with different acquisition parameters, especially the number of accumulations. This performance analysis has shown that the RLS Sim in its updated configuration will be a key model to perform support science for the ExoMars mission and the RLS instrument on the Rosalind Franklin rover. Designed to work intensively, the use of the RLS Sim in combination with the RLS FS will facilitate maximizing the scientific return of the RLS spectrometer during Martian operations.Secretaría de Estado de Investigación, Desarrollo e Innovación (grant PID2019-107442RBC31)European Union’s Horizon 2020 research and innovation program (grant 687302