Person:
González García, Esther

person.page.identifierURI

https://academica-e.unavarra.es/handle/2454/49176

Last Name

González García

First Name

Esther

person.page.departamento

Ciencias

person.page.instituteName

IMAB. Research Institute for Multidisciplinary Applied Biology

ORCID

0000-0002-1379-9398

person.page.upna

1764

Full item page

Search Results

Now showing 1 - 10 of 21

Open Access
Physiological responses of legume nodules to drought
(Global Science Books, 2011) Arrese-Igor Sánchez, César; González García, Esther; Marino Bilbao, Daniel; Ladrera Fernández, Rubén; Larrainzar Rodríguez, Estíbaliz; Gil Quintana, Erena; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Legumes include important agricultural crops, as their high protein content is of primary importance for human food and animal feed. In addition, the ability of most of them to establish symbiotic relationships with soil bacteria allows them to obtain their N requirements from nitrogen fixation in nodules and, therefore, avoids the use of nitrogen fertilizers. Thus, legumes are also essential to improve the soil fertility and quality of agricultural lands and to reclaim eroded or barren areas, making them crucial for agricultural and environmental sustainability. However, legume nitrogen fixation in crop species is very sensitive to environmental constraints and drought, in particular. The present contribution reviews our current knowledge on the processes involved in this inhibition, with particular emphasis on oxygen, nitrogen and carbon physiology. Emerging aspects such as oxidative damage, C/N interactions and sulphur metabolism together with future prospects are also discussed.
Open Access
Split‐root systems applied to the study of the legume‐rhizobial symbiosis: what have we learned?
(Wiley, 2014) Larrainzar Rodríguez, Estíbaliz; Gil Quintana, Erena; Arrese-Igor Sánchez, César; González García, Esther; Marino Bilbao, Daniel; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Split-root system (SRS) approaches allow the differential treatment of separate and independent root systems, while sharing a common aerial part. As such, SRS is a useful tool for the discrimination of systemic (shoot origin) versus local (root/nodule origin) regulation mechanisms. This type of approach is particularly useful when studying the complex regulatory mechanisms governing the symbiosis established between legumes and Rhizobium bacteria. The current work provides an overview of the main insights gained from the application of SRS approaches to understand how nodule number (nodulation autoregulation) and nitrogen fixation are controlled both under non-stressful conditions and in response to a variety of stresses. Nodule number appears to be mainly controlled at the systemic level through a signal which is produced by nodule/root tissue, translocated to the shoot, and transmitted back to the root system, involving shoot Leu-rich repeat receptor-like kinases. In contrast, both local and systemic mechanisms have been shown to operate for the regulation of nitrogenase activity in nodules. Under drought and heavy metal stress, the regulation is mostly local, whereas the application of exogenous nitrogen seems to exert a regulation of nitrogen fixation both at the local and systemic levels.
Open Access
iNaturalist Arga: acercándonos a la biodiversidad de los ríos urbanos para aprender a cuidarlos
(Fundación Conama, 2021) González García, Esther; Peralta de Andrés, Francisco Javier; García, Mar; Alzueta, José; Fernández Escalada, Manuel; Marzo Pérez, Asier; Aliende, Andrea; Miguel, Jon; Alvira Guallart, María Aránzazu; Ciencias; Zientziak; Gobierno de Navarra / Nafarroako Gobernua, CENEDUCA3-2019
La biodiversidad es un concepto que forma parte del currículo de la educación secundaria. Las herramientas TIC (Tecnologías de la Información y la Comunicación) colaborativas abiertas disponibles ofrecen nuevas posibilidades para el ampliar el conocimiento sobre biodiversidad de los estudiantes de secundaria y futuros ciudadanos. Este estudio utiliza la plataforma de ciencia ciudadana iNaturalist como herramienta de utilidad en el currículo sobre biodiversidad incluido en la educación secundaria obligatoria. En este contexto, se ha creado un proyecto en esta plataforma centrado en el río Arga que atraviesa la ciudad de Pamplona: https://www.inaturalist.org/projects/arga. El proyecto implica a centros de educación secundaria, formación profesional y educación ambiental para realizar observaciones sobre biodiversidad en el entorno dicho río. Su objetivo es mejorar el conocimiento de los estudiantes de educación secundaria del concepto biodiversidad así como del río, además de poner en valor este ecosistema fluvial en un entorno urbano en las futuras generaciones. El proyecto fue puesto en marcha en el curso 2019-2020 e incorpora 468 observaciones de 213 especies aportadas por 39 observadores y 140 identificadores han colaborado en su validación. Aunque la participación en ese curso fue limitada a un centro educativo como consecuencia de la pandemia COVID, esta experiencia ha servido como modelo para el futuro desarrollo del proyecto. En el curso 2020-2021 se vuelve a poner en marcha el proyecto ARGA con el objetivo de establecerse como una herramienta de referencia para la comunidad educativa y de conectar el sector educativo con la sociedad en torno al concepto biodiversidad para destacar su importancia en la calidad ambiental en medios urbanos.
Open Access
Insights into the regulation of nitrogen fixation in pea nodules: lessons from drought, abscisic acid and increased photoassimilate availability
(EDP Sciences, 2001) González García, Esther; Gálvez, Loli; Royuela Hernando, Mercedes; Aparicio Tejo, Pedro María; Arrese-Igor Sánchez, César; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Nitrogen fixation in legume nodules has been shown to be very sensitive to drought and other environmental constraints. It has been widely assumed that this decline in nitrogen fixation was a consequence of an increase in the so-called oxygen diffusion barrier and a subsequent impairment to bacteroid respiration. However, it has been recently shown that nitrogen fixation is highly correlated with nodule sucrose synthase (SS) activity under drought and other environmental stresses. Whether this correlation reflects a causative relationship or not has not been proven yet. The evidence presented here suggests that SS controls nitrogen fixation under mild drought conditions. However, nitrogen fixation cannot be enhanced only by increasing glycolytic flux, as under these conditions nodules become oxygen limited. Abscisic acid also induces a decline in nitrogen fixation that is independent of SS. The overall results suggest the occurrence of a complex regulation of nodule nitrogen fixation involving, at least, both carbohydrate and oxygen fluxes within the nodule.
Open Access
Is N-feedback involved in the inhibition of nitrogen fixation in drought-stressed Medicago truncatula?
(Oxford University Press, 2013) Gil Quintana, Erena; Larrainzar Rodríguez, Estíbaliz; Arrese-Igor Sánchez, César; González García, Esther; Ciencias del Medio Natural; Natura Ingurunearen Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa: 735/2008
Drought stress is a major factor limiting nitrogen fixation (NF) in crop production. However, the regulatory mechanism involved and the origin of the inhibition, whether local or systemic, is still controversial and so far scarcely studied in temperate forage legumes. Medicago truncatula plants were symbiotically grown with a split-root system and exposed to gradual water deprivation. Physiological parameters, NF activity, and amino acid content were measured. The partial drought treatment inhibited NF in the nodules directly exposed to drought stress. Concomitantly, in the droughted below-ground organs, amino acids accumulated prior to any drop in evapotranspiration (ET). It is concluded that drought exerts a local inhibition of NF and drives an overall accumulation of amino acids in diverse plant organs which is independent of the decrease in ET. The general increase in the majority of single amino acids in the whole plant questions the commonly accepted concept of a single amino acid acting as an N-feedback signal.
Open Access
Potencialidades del frijol caupí para la resiliencia al cambio climático en sistemas agrícolas locales
(2022) Santana-Baños, Yoerlandy; González García, Esther; Ariz Arnedo, Idoia; Carrodeguas Díaz, Sergio; Ciencias; Zientziak
Las evidencias científicas sugieren tres usos fundamentales del frijol caupí, con agro-ecológicas y beneficios productivos, sociales y ambientales en los sistemas agrícolas locales; sin embargo, su rendimiento a nivel mundial y en América no experimenta crecimiento en los últimos años. Los resultados obtenidos en Pinar del Río, Cuba, sugieren la posibilidad de emplearlo como alternativa para la producción de grano pero debe fomentarse, desde la ciencia, la innovación y las instituciones y órganos de decisión a nivel local, la cultura de producción y consumo de esta leguminosa para su aprovechamiento en la sostenibilidad agrícola de los agro-ecosistemas.
Open Access
Nodule carbohydrate catabolism is enhanced in the Medicago truncatula A17-Sinorhizobium medicae WSM419 symbiosis
(Frontiers Media, 2014) Larrainzar Rodríguez, Estíbaliz; Gil Quintana, Erena; Seminario Huárriz, Amaia; Arrese-Igor Sánchez, César; González García, Esther; Ciencias del Medio Natural; Natura Ingurunearen Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
The symbiotic association between Medicago truncatula and Sinorhizobium meliloti is a well-established model system in the legume–Rhizobium community. Despite its wide use, the symbiotic efficiency of this model has been recently questioned and an alternative microsymbiont, S. medicae, has been proposed. However, little is known about the physiological mechanisms behind the higher symbiotic efficiency of S. medicae WSM419. In the present study, we inoculated M. truncatula Jemalong A17 with either S. medicae WSM419 or S. meliloti 2011 and compared plant growth, photosynthesis, N2-fixation rates, and plant nodule carbon and nitrogen metabolic activities in the two systems. M. truncatula plants in symbiosis with S. medicae showed increased biomass and photosynthesis rates per plant. Plants grown in symbiosis with S. medicae WSM419 also showed higher N2-fixation rates, which were correlated with a larger nodule biomass, while nodule number was similar in both systems. In terms of plant nodule metabolism, M. truncatula–S. medicae WSM419 nodules showed increased sucrose-catabolic activity, mostly associated with sucrose synthase, accompanied by a reduced starch content, whereas nitrogen-assimilation activities were comparable to those measured in nodules infected with S. meliloti 2011. Taken together, these results suggest that S. medicae WSM419 is able to enhance plant carbon catabolism in M. truncatula nodules, which allows for the maintaining of high symbiotic N2-fixation rates, better growth and improved general plant performance.
Open Access
Long-term mannitol-induced osmotic stress leads to stomatal closure, carbohydrate accumulation and changes in leaf elasticity in Phaselous vulgaris leaves
(Academic Journals, 2010) Sassi, Sameh; Aydi, Samir; Hessini, Kamel; González García, Esther; Arrese-Igor Sánchez, César; Abdelly, Chedly; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
The effect of long-term osmotic stress was investigated in leaves of two common bean lines, with contrasting tolerance: Flamingo (tolerant) and coco blanc (sensitive). Water relations, organic solute, ion accumulation and amino acids content as well as osmotic adjustment (OA) were studied during an extended exposure to osmotic stress. Osmotic stress was applied by means of 50 mM mannitol for 15 days. At the end of the stress period, both osmotic potential at full turgor (psi(100)) and at turgor loss point (psi(0)) decreased significantly in stressed plants compared with the control. The decrease being greater in the sensitive line, showed a greater OA compared with flamingo. Sugars contents increased in stressed plants and seem to be the major components of osmotic adjustment in stressed common bean leaves. The increase was more marked in coco blanc. Osmotic stress tolerance could thus not be associated with higher OA. The possible role of decreased leaf cell elasticity (epsilon(max)) is discussed in relation to osmotic stress tolerance in this species.
Open Access
Estudio de prospectiva, análisis y propuesta de participación y colaboración de la Administración Foral de Navarra con las redes, plataformas e iniciativas de ciencia ciudadana
(2016) González García, Esther; Peralta de Andrés, Francisco Javier; Imbert Rodríguez, Bosco; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
El objetivo de este trabajo es analizar las redes y plataformas de ciencia ciudadana existentes con el fin de realizar una propuesta para su implementación en Navarra por parte de la Administración Ambiental; para ello se revisa cómo abordan otras administraciones la ciencia ciudadana a distintos niveles y las posibles formas de participación o colaboración de la Administración.
Open Access
Learning plant biodiversity in nature: the use of the citizen–science platform iNaturalist as a collaborative tool in secondary education
(MDPI, 2021) Echeverría Obanos, Andrés; Ariz Arnedo, Idoia; Moreno Echeverría, Judit; Peralta de Andrés, Francisco Javier; González García, Esther; Zientziak; Institute for Multidisciplinary Research in Applied Biology - IMAB; Ciencias; Gobierno de Navarra / Nafarroako Gobernua, CENEDUCA3/2019
Biodiversity is a concept of great scientific interest and social value studied in different subjects of the secondary education curriculum. Citizen–science programs may contribute to increasing the engagement of students when studying biodiversity. This work aimed to explore the use of the citizen–science platform iNaturalist as a complement of the elaboration of herbaria in an outdoor activity for 4th course 16-year-old students in the Basaula Reserve. The platform iNaturalist was chosen for its suitability to develop collaborative projects in an educational context. The Basaula project was created and 122 students were trained to record plant species in an outdoor activity. A total of 32 species were recorded, among them the most abundant were beech (Fagus sylvatica) and holm oak (Quercus ilex). The students positively evaluated their experience, highlighting its adequacy to record biodiversity data and make a virtual herbarium. Students valued the innovative character of iNaturalist and its usefulness for research but also the opportunity to integrate mobile devices in school education. We concluded that iNaturalist is a valuable tool to carry out collaborative projects dealing with biodiversity in secondary education.