Plasticidad fenotípica de Pinus pinaster frente a la disponibilidad de nutrientes

7 páginas, 4 figuras, 1 tabla -- Comunicación presentada en la IV Reunión sobre Genética Forestal (2008), celebrada en Pontevedra entre el 27 y el 29 de junio de 2007.En tres ensayos factoriales familia x fertilización situados en sitios de baja fertilidad en el Sur de Galicia se analizó la plasticidad fenotípica en el desarrollo y la variación genética en plasticidad en familias de medios hermanos de Pinus pinaster. La autocorrelación espacial que presentaron las variables de estudio invalidaron las técnicas de análisis convencional, siendo necesario ajustar los datos espacialmente mediante técnicas de geoestadística. En las tres parcelas se encontró variación genética en el crecimiento de la población de estudio además de plasticidad fenotípica frente a la disponibilidad de nutrientes en el gradiente de fertilización ensayado. En concordancia con estudios nutricionales previos en Galicia, la fertilización resultó ser beneficiosa para el crecimiento de las plantas. También se encontró variación genética en la plasticidad en todas las parcelas, lo que indica que existen variaciones genéticas en la eficacia nutricional entre las familias estudiadas. Sin embargo, la interacción fertilización x sitio, familia x sitio y familia x fertilización x sitio muestra un patrón de respuesta complejo.Este trabajo se ha realizado al amparo del Proyecto de Investigación INIA-RTA05-173.Peer reviewe

Genetic variation and phenotypic plasticity of nutrient re-allocation and increased fine root production as putative tolerance mechanisms inducible by methyl jasmonate in pine trees

1. Plant plastic responses to herbivore damage may include rapid, active reallocation of plant resources to reduce the impact of herbivory on future plant fitness. However, whether these inducible tolerance responses can be extended to pine trees and how these responses could be modulated by genetic and environmental factors remains unclear.2. Biomass allocation and phosphorus (P) and nitrogen (N) concentrations in above- and belowground tissues were measured in Pinus pinaster juveniles belonging to 33 open-pollinated families grown under two P availabilities (P-deficient and complete fertilization). Measurements were taken 15 days after half of the plants received a foliar spray treatment of 22 mmol L)1 methyl jasmonate (MJ) to simulate above-ground herbivore attack.3. Simulated above-ground herbivory promoted a strong preferential allocation of biomass below ground in the form of fine roots, leading to an almost two-fold increase in fine root biomass in MJ-treated plants and a significant reduction in above-ground tissues and coarse roots. In addition, MJ signalling increased P andN concentrations in the shoots while reducing (P) or maintaining (N) concentrations in the roots. These results suggest that induced resource sequestration is not a generalized strategy in this pine species. Fine root biomass and concentration of N and P in plant tissues showed additive genetic variation, but responses to MJ signalling did not vary among families. Allocation of biomass to fine roots was not affected by P availability, whereas allocation of P to the shoot was more intense under complete fertilization.4. Synthesis: Two new putative tolerance mechanisms inducible by MJ signalling may help to minimize the impact of above-ground herbivore damage on the future fitness of young pine trees by (i) allocation of carbon to fine roots, this appeared to be a generalized strategy with weak environmental modulation and (ii) reallocation of P and N from roots to shoots, which was largely affected by P availability, and thus susceptible to greater phenotypic variation in heterogeneous environments. We provide evidence that changes in tolerance-related traits are rapidly inducible by herbivory cues in this pine species. These results should be integrated with induced resistance responses to fully understand the costs and benefits associated with induced responses to herbivory.This research was supported by the grants AGL2010-18724, RTA07-100, PSE310000. LS and XM received financial support from DOC-INIA and PREDOC-INIA grant programs respectively.INIAPeer Reviewe

Phenotypic plasticity of maritime pine to insect herbivory

PósterPeer Reviewe

Nutritional status and genetic variation in the response to nutrient availability in Pinus pinaster. A multisite field study in NW Spain

The low nutrient availability of the acidic and sandy soils of Galicia (Northwest Spain) is probably the main environmental factor limiting forest primary productivity in the area. These particular edaphic conditions could have imposed selective pressures on maritime pine populations leading to specific local adaptations. We first assessed the nutritional status of 22 young contemporary Pinus pinaster plantations in Northwest Spain, and then analysed the response to fertilization in three family × fertilization trials, and how this response varied across sites and genotypes. Growth of P. pinaster in Northwest Spain appeared to be largely limited by nutrient availability, where most of the plantations showed severe nutrient deficiencies, especially in P and Mg. According to these deficiencies, a strong positive response to nutrient additions was observed in the three trials, with height increments of up to 30% compared with the unfertilized control. However, the response to fertilizers was very variable from site to site, and in some cases did not agree with the foliar nutritional diagnosis. The response to fertilization was also significantly affected by pine genotype, suggesting that the plastic response to nutrient additions within each environment was under genetic control. However, the family response to nutrient availability was not consistent across sites, and no significant differences among families were observed for the RDPI plasticity index – a single index that summarizes the phenotypic change in multiple environments – when analysed across environments. The strong environmental component modulating phenotypic responses to fertilization could impose an important obstacle to evolve specific adaptations to the local edaphic conditions, as well as to artificially select genotypes adapted to different environments and silviculture regimes.This research was funded by the INIA projects RTA05-173 and RTA07-100.Peer reviewe

From Invisibility to the Public Sphere: The Hybrid Media Strategy of a New Party (Podemos, Spain, 2014–2015)

How does a new party manage to move from invisibility to occupying a central position in the public debate? How does it gain the attention of the mainstream media and recognition by the public and the institutions linked to sociopolitical and economic power? This article examines the media strategy followed by the Spanish party Podemos in its first year of activity. We apply quantitative and longitudinal methods to analyze the attention paid to Podemos by television channels, newspapers, online press, and digital networks. Results show that the party prioritized antagonistic talk shows, infotainment, and self-produced television programs, which combined to create a viral presence on digital networks and led to its leaders appearing on mainstream TV channels. This hybrid strategy took the party from media invisibility to the central public sphere, though traditional dependence on favorable opinion polls and electoral success were also relevant

Genetics, phosphorus availability, and herbivore-derived induction as sources of phenotypic variation of leaf volatile terpenes in a pine species

Oleoresin produced and stored in pine tree leaves provides direct resistance to herbivores, while leaf volatile terpenes (LVT) in the resin are also powerful airborne infochemicals. Resin concentration and profile show considerable spatial and temporal phenotypic variation within and among pine populations. LVT biochemistry is known to be under genetic control, and although LVT should be plastic to diverse abiotic and biotic environmental factors such as nutrient availability and herbivore attack, little is known about their relative contributions and interactive effects. The aim of this paper was to clarify whether reduced phosphorus availability could increase the LVT concentration and affect the expression of herbivore-derived induced defences, and how plasticity would contribute to the phenotypic variation of LVT. The constitutive and methyl-jasmonate (MeJa) induced LVT concentration and profile were analysed in 17 half-sib Pinus pinaster families growing under two levels of P-availability (complete and P-limited fertilization). Individual terpene concentrations showed large additive genetic variation, which was more pronounced in the control than in MeJa-induced pines. MeJa application did not affect the LVT concentration, but significantly modified the LVT profile by depleting the α-pinene content and reducing the sesquiterpene fraction. Low P-availability strongly reduced plant growth and foliar nutrient concentrations, but did not affect LVT concentration and profile, and did not interact with MeJa-induction. Results indicate a strong homeostasis of LVT concentration to P-availability, and minor changes in the LVT profile due to MeJa-induction. Genetic variation appears to be the main source of phenotypic variation affecting the LVT concentration in this pine species.This work was supported by the Spanish Instituto Nacional de Investigación y Tecnología Agraria y Agroalimentaria (grant number INIA-RTA07-100; and DOC-INIA and PREDOC-INIA fellows for LS and XM, respectively); the Spanish Agency of Science and Technology (grant numbers CGL2006-04025/BOS, CGL2010-17172, and CSD2008- 00040 for JP and JL; and AGL2010-18724 and PSE310000 for RZ and LS); and the Catalonian Government (grant number SGR 2009-1458).Peer reviewe

Sete anos de guerra no Afeganistão: desafios políticos e novas estratégias

Ao final de sete anos de conflito no Afeganistão, verificam-se tendências estruturais que impõem novos desafios aos atores internacionais, regionais e domésticos envolvidos. O texto analisa a influência das forças internacionais e regionais nas principais dinâmicas do conflito e o papel de cada uma delas na resolução da crise.Ao final de sete anos de conflito no Afeganistão, verificam-se tendências estruturais que impõem novos desafios aos atores internacionais, regionais e domésticos envolvidos. O texto analisa a influência das forças internacionais e regionais nas principais dinâmicas do conflito e o papel de cada uma delas na resolução da crise

Densidad y área de los canales resiníferos de "Pinus pinaster" ante tratamientos de fertilización, y su relación con la defensa ante "Hylobius abietis"

6 páginas, 3 tablas -- Actas de la I Reunión sobre Sanidad Forestal celebrada en Palencia el 24 y 25 de septiembre de 2007.Las coníferas poseen una estructura de canales resiníferos que actúa como defensa contra el ataque de insectos y patógenos. Varios autores han observado que un aumento en la disponibilidad de nutrientes puede alterar el reparto de energía en las plantas, en detrimento de los sistemas defensivos. El presente estudio tiene como objetivo determinar el efecto de la fertilización de establecimiento sobre el desarrollo del sistema de canales resiníferos en Pinus pinaster. Mediante histología en brinzales de 3 savias sometidos a dos ensayos familia x fertilización se cuantificó la densidad y el área de los canales resiníferos del floema y del xilema tanto en el tallo principal como en ramas laterales en dos ensayos familia x fertilización. Se observó un efecto significativo de la fertilización en el desarrollo de los canales resiníferos del floema (p<0,05), con valores de 0,45 y 0,36 canales.mm-2 para brinzales no fertilizados y sí fertilizados, respectivamente. Este efecto no se observó en las variables del xilema. La densidad de canales resiníferos en el xilema fue significativamente diferente entre las dos parcelas estudiadas, siendo mayor en la atacada por el curculiónido Hylobius abietis. Por último, la relación tallo-rama de las variables cuantificadas no fue lo suficientemente consistente como para utilizar los canales en ramas de P. pinaster como indicadores de los canales en el tronco principal.Este trabajo se ha realizado bajo financiación del proyecto INIA-RTA05-173.Peer reviewe

Drought stress modifies early effective resistance and induced chemical defences of Aleppo pine against a chewing insect herbivore

During their long lifespan, pines must cope with simultaneous abiotic and biotic stresses such as drought and herbivory. Mediterranean pines are isohydric species that rapidly close their stomata in response to drought reducing carbon fixation. In such situations, the synthesis of chemical defences could be impaired. Here, we tested the hypothesis that drought stress may constrain the capability of Mediterranean pines to defend against herbivory and to induce chemical defences. For this purpose, we subjected three contrasting populations of Aleppo pine (Pinus halepensis Mill.) to three levels of drought stress, thereafter exposing the seedlings to the herbivore Hylobius abietis L. A suite of ecophysiological and defensive traits was measured to explore the interaction between both stresses. Drought significantly affected the 13C signature and reduced starch and fatty acids concentration. Damage caused by the insect was affected by drought stress, being 75% higher at the moderate stress level but returning under severe stress to similar values as control seedlings. Seedlings responded to herbivory by decreasing the concentration of total polyphenolics and condensed tannins, increasing the concentration of total diterpenes, and modifying the profile of major terpenes. Induced responses to herbivory were, as expected, altered by drought. Inducibility of polyphenolics decreased as drought stress increased while for diterpenes it was higher at moderate stress. Moreover, a significant drought × herbivory interaction was found on the multivariate terpene profile. These results should be considered for predicting responses of pine forests to the forecasted increase of abiotic and biotic risks associated with global change.This research was supported by the grants AGL2012-40151-C03-01, AGL2015-68274-C03-02-R and AGL2015-68274-C03-03-R, founded by MINECO/FEDER. E.S-V. received financial support from the FPU grant program (Ministerio de Educación, Cultura y Deporte Gobierno de España)

Antibody response in patients admitted to the hospital with suspected SARS-CoV-2 infection: results from a multicenter study across Spain

Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Diagnòstic; IgACoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Diagnóstico; IgACoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Diagnosis; IgAAim To evaluate the serological response against SARS-CoV-2 in a multicenter study representative of the Spanish COVID pandemic. Methods IgG and IgM + IgA responses were measured on 1466 samples from 1236 Spanish COVID-19 patients admitted to the hospital, two commercial ELISA kits (Vircell SL, Spain) based on the detection of antibodies against the viral spike protein and nucleoprotein, were used. Results Approximately half of the patients presented antibodies (56.8% were IgM + IgA positive and 43.0% were IgG positive) as soon as 2 days after the first positive PCR result. Serological test positivity increased with time from the PCR test, and 10 days after the first PCR result, 91.5% and 88.0% of the patients presented IgM + IgA and IgG antibodies, respectively. Conclusion The high values of sensitivity attained in the present study from a relatively early period of time after hospitalization support the use of the evaluated serological assays as supplementary diagnostic tests for the clinical management of COVID-19.The ELISA kits for the IgG and IgM + IgA assays were provided by Vircell SL. No additional funding was received