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
Drought stress tolerance in plants
(MDPI, 2023) González García, Esther; Ciencias; Zientziak; Institute for Multidisciplinary Research in Applied Biology - IMAB
The current climate change scenario is accelerating degradation, desertification, and salinisation: all destructive processes that are negatively impacting arable lands and food production. This is particularly important when considering how the world population shows a marked positive trend. This scenario leads to flooding and decreasing water quality, but also to a decrease in the availability of water resources in some regions. More than ever, drought is a significant threat to agriculture worldwide. This Special Issue focuses on recent advances in the mechanisms involved in the drought tolerance of crop plants, with particular attention to the role of the root tissue and shoot¿root interactions. In addition to drought, it considers other abiotic stresses involving water deficit stress at the cell level and their interactions with drought. The Special Issue includes a review paper and a collection of scientific papers that approach drought stress in cereals, legumes, and trees, combining studies in cultivated, wild, and model plants. Overall, this issue remarks the role of transcriptions factors (bHLH, NAC, HD-ZIP III), leucine-rich repeat receptor-like kinases, cytochrome P450 monooxygenases, and U-box E3 ligases in drought stress responses at different levels. In addition, the interaction between plant nutrition and drought stress responses is approached with a physiological strategy.
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
Proyecto río Arga: ciencia ciudadana, biodiversidad & educación
(2022) González García, Esther; Peralta de Andrés, Francisco Javier; Ciencias; Zientziak; Gobierno de Navarra / Nafarroako Gobernua, CENEDUCA3-2019
El objetivo del proyecto ARGA, desarrollado en la plataforma iNaturalist (https://www.inaturalist.org/projects/arga), es reunir observaciones de las especies presentes en el río Arga a su paso por la Cuenca de Pamplona. Cualquier persona puede participar, aunque en su creación se ha pensado en su utilización principalmente por estudiantes de Enseñanza Secundaria. Este proyecto se lleva a cabo en colaboración con la Mancomunidad de la Comarca de Pamplona a través del programa Mancoeduca, que ofrece actividades de educación ambiental dirigidas a centros de educación secundaria en el entorno del río Arga.
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
Local inhibition of nitrogen fixation and nodule metabolism in drought-stressed soybean
(Oxford University Press, 2013) Gil Quintana, Erena; Larrainzar Rodríguez, Estíbaliz; Seminario Huárriz, Amaia; Díaz Leal, Juan Luis; Alamillo, Josefa M.; Pineda, Manuel; Arrese-Igor Sánchez, César; Wienkoop, Stefanie; González García, Esther; Ciencias del Medio Natural; Natura Ingurunearen Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa: 735/2008; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa: 134/2012
Drought stress is a major factor limiting symbiotic nitrogen fixation (NF) in soybean crop production. However, the regulatory mechanisms involved in this inhibition are still controversial. Soybean plants were symbiotically grown in a split-root system (SRS), which allowed for half of the root system to be irrigated at field capacity while the other half remained water deprived. NF declined in the water-deprived root system while nitrogenase activity was maintained at control values in the well-watered half. Concomitantly, amino acids and ureides accumulated in the water-deprived belowground organs regardless of transpiration rates. Ureide accumulation was found to be related to the decline in their degradation activities rather than increased biosynthesis. Finally, proteomic analysis suggests that plant carbon metabolism, protein synthesis, amino acid metabolism, and cell growth are among the processes most altered in soybean nodules under drought stress. Results presented here support the hypothesis of a local regulation of NF taking place in soybean and downplay the role of ureides in the inhibition of NF
Open Access
Physiological and biochemical characterization of rootlets response to salt stress in two Medicago truncatula Gaertn. ecotypes
(Japanese Society for Root Research, 2018) Amouri, Adel Amar; González García, Esther; Aoul, Seghir Hadjadj; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Legumes are very important plants both ecologically and agriculturally because they are able to interact symbiotically with rhizobia for biological nitrogen fixation and soil fertilization. Medicago truncatula Gaertn. is an important model legume rich in protein. Salinity represents, today, the major cause of land degradation and crop productivity limitation around the world and affects physiology and metabolism in legumes. In this study, we analyzed the physiological and biochemical responses of rootlets in two contrasting ecotypes of Medicago truncatula (Tru 131, tolerant and Jemalong, sensitive) to different level of NaCl, (68, 102 and 137 mM). Results showed that the tolerant ecotype has a lower water potential than Jemalong. Root protein content of Tru 131 was decreased than Jemalong, this can be explained by accumulation of protein oxidation in the sensitive genotype. Moreover, NaCl increased guaiacol peroxidase activity GPX in rootlets of Tru 131, this enzyme has a protective role against the molecules ROS accumulated during oxidative stress. On the other hand, under salt stress the total content of ascorbate (ASC + DHA) and Glutathione (GSH + GSSG) was increased in the tolerant genotype Tru 131 compared to Jemalong. These results show how the tolerant genotype activate the antioxidative defense system at root level against damages caused by oxidative stress under salinity.
Open Access
Phloem sap proteins are part of a core stress responsive proteome involved in drought stress adjustment
(Frontiers Media, 2021-01-02) Castañeda Presa, Verónica; González García, Esther; Wienkoop, Stefanie ; Ciencias; Zientziak; Institute for Multidisciplinary Research in Applied Biology - IMAB; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
During moderate drought stress, plants can adjust by changes in the protein profiles of the different organs. Plants transport and modulate extracellular stimuli local and systemically through commonly induced inter- and intracellular reactions. However, most proteins are frequently considered, cell and organelle specific. Hence, while signaling molecules and peptides can travel systemically throughout the whole plant, it is not clear, whether protein isoforms may exist ubiquitously across organs, and what function those may have during drought regulation. By applying shotgun proteomics, we extracted a core proteome of 92 identical protein isoforms, shared ubiquitously amongst several Medicago truncatula tissues, including roots, phloem sap, petioles, and leaves. We investigated their relative distribution across the different tissues and their response to moderate drought stress. In addition, we functionally compared this plant core stress responsive proteome with the organ-specific proteomes. Our study revealed plant ubiquitous protein isoforms, mainly related to redox homeostasis and signaling and involved in protein interaction networks across the whole plant. Furthermore, about 90% of these identified core protein isoforms were significantly involved in drought stress response, indicating a crucial role of the core stress responsive proteome (CSRP) in the plant organ cross-communication, important for a long-distance stress-responsive network. Besides, the data allowed for a comprehensive characterization of the phloem proteome, revealing new insights into its function. For instance, CSRP protein levels involved in stress and redox are relatively more abundant in the phloem compared to the other tissues already under control conditions. This suggests a major role of the phloem in stress protection and antioxidant activity enabling the plants metabolic maintenance and rapid response upon moderate stress. We anticipate our study to be a starting point for future investigations of the role of the core plant proteome. Under an evolutionary perspective, CSRP would enable communication of different cells with each other and the environment being crucial for coordinated stress response of multicellular organisms.
Open Access
Legume nitrogen utilization under drought stress
(Springer, 2018) Castañeda Presa, Verónica; Gil Quintana, Erena; Echeverría Obanos, Andrés; González García, Esther; Ciencias; Zientziak
Legumes account for around 27% of the world’s primary crop production and can be classified based on their use and traits into grain and forage legumes. Legumes can establish symbiosis with N-fixing soil bacteria. As a result, a new organ is formed, the nodule, where the reduction of atmospheric N2 into ammonia is carried out catalyzed by the bacterial exclusive enzyme nitrogenase. The process, highly energy demanding, is known as symbiotic nitrogen fixation and provides all the N needs of the plant, thus avoiding the use of N fertilizers in the context of sustainable agriculture. However, legume crops are often grown under non-fixing conditions since legume nodulation is suppressed by high levels of soil nitrogen occurring in chemically fertilized agro-environment. In addition, legumes are very sensitive to environmental stresses, being drought one of the significant constraints affecting crop production. Due to their agricultural and economic importance, scientists have carried out basic and applied research on legumes to better understand responses to abiotic stresses and to further comprehend plant–microbe interactions. An integrated view of nitrogen utilization under drought stress will be presented with particular focus on legume crops.