Valoración cultural y paisajística de conjuntos poblacionales rurales: comarca del Altiplano (Murcia/Sureste de España)

Los asentamientos humanos rurales forman parte del patrimonio cultural y paisajístico de Europa, y su valoración objetiva es fundamental para establecer programas de recuperación y desarrollo, constituyendo el objetivo fundamental de este trabajo. Para ello, se estableció una metodología cuantitativa basada en el análisis, mediante ecuaciones ponderadas, de dos áreas o coronas, una interior y otra exterior, de los núcleos poblacionales, que permitía obtener un valor numérico global denominado “valor cultural y paisajístico”. Esta metodología fue aplicada a una selección de 9 asentamientos humanos rurales de la comarca murciana del Altiplano. Los asentamientos que mostraron valores más altos albergaban elementos con mayor valoración arquitectónica y natural, destacando Fuente del Pino, por su huerta tradicional y la presencia de elementos arquitectónicos significativos, y Santa Ana del Monte, por estar situado en un enclave natural protegido y contar con un antiguo convento. Por el contrario, Casas de Pinillos, situado en una zona esteparia con intensa transformación agrícola, fue el asentamiento que presentó un valor más bajo.  Por tanto, el abordaje objetivo, mediante ecuaciones, de la valoración cultural y paisajística de los conjuntos poblacionales rurales permite una aproximación sencilla, pero a la vez muy robusta, sobre su potencialidad de desarrollo, que está abierta a posibles modificaciones y mejoras en función del grado de profundización requerido

CAX1a TILLING Mutations Modify the Hormonal Balance Controlling Growth and Ion Homeostasis in Brassica rapa Plants Subjected to Salinity

Salinity is a serious issue for crops, as it causes remarkable yield losses. The accumulation of Na+ a ects plant physiology and produces nutrient imbalances. Plants trigger signaling cascades in response to stresses in which phytohormones and Ca2+ are key components. Cation/H+ exchangers (CAXs) transporters are involved in Ca2+ fluxes in cells. Thus, enhanced CAX activity could improve tolerance to salinity stress. Using the TILLING (targeting induced local lesions in genomes) technique, three Brassica rapa mutants were generated through a single amino acidic modification in the CAX1a transporter. We hypothesized that BraA.cax1a mutations could modify the hormonal balance, leading to improved salinity tolerance. To test this hypothesis, the mutants and the parental line R-o-18 were grown under saline conditions (150 mM NaCl), and leaf and root biomass, ion concentrations, and phytohormone profile were analyzed. Under saline conditions, BraA.cax1a-4 mutant plants increased growth compared to the parental line, which was associated with reduced Na+ accumulation. Further, it increased K+ concentration and changed the hormonal balance. Specifically, our results show that higher indole-3-acetic acid (IAA) and gibberellin (GA) concentrations in mutant plants could promote growth under saline conditions, while abscisic acid (ABA), ethylene, and jasmonic acid (JA) led to better signaling stress responses and water use e ciency. Therefore, CAX1 mutations directly influence the hormonal balance of the plant controlling growth and ion homeostasis under salinity. Thus, Ca2+ signaling manipulation can be used as a strategy to improve salinity tolerance in breeding programs.PAI program (Plan Andaluz de Investigación, Grupo de Investigación) AGR282National Health and Medical Research Council of Australia German Research Foundation (DFG) FPU14/0185

The implication of sucrose metabolism in the rootstock- mediated contrasting growth and yield responses of pepper plants subjected to salinity stress

[ESP] La tecnología del injerto modifica el balance reproductivo de plantas, que está controlado por el flujo de fotoasimilados hacia los frutos. El objetivo de este trabajo fue estudiar el efecto del injerto sobre la tasa de hidrólisis de sacarosa en frutos de plantas de pimiento sometidas a estrés salino. En condiciones salinas, las concentraciones de glucosa y fructosa disminuyeron significativamente en plantas injertadas sobre Terrano, que indica una mayor utilización en los órganos sumidero por su alta tasa reproductiva. Sin embargo, en plantas injertadas sobre Atlante, con una menor tasa reproductiva, se produjo una acumulación de sacarosa en condiciones salinas, que podría ser debida a una ralentización de su actividad sacarolítica. Por tanto, existen respuestas diferenciales en el metabolismo de la sacarosa de frutos de plantas de pimiento sometidas a estrés salino, que podrían explicar las diferencias de desarrollo asociadas al tipo de portainjerto utilizado. [ENG] Grafting technology modifies the reproductive balance of plants, which is controlled by the flow of photoassimilates to the fruits. The objective of this work was to study the effect of grafting on the rate of sucrose hydrolysis in fruits of pepper plants subjected to salt stress. Under saline conditions, glucose and fructose concentrations decreased significantly in plants grafted on Terrano, which indicates a higher utilization in the sink organs due to its high reproductive rate. However, in plants grafted onto Atlante, with a lower reproductive rate, there was an accumulation of sucrose in saline conditions, which could be due to a slowdown in its saccharolytic activity. Therefore, there are differential responses in the metabolism of sucrose in the fruits of pepper plants subjected to salt stress, which could explain the differences in development associated with the type of rootstock used

Rootstock-mediated regulation of saccharolytic activity in pepper plants under saline stress conditions

[SPA] Los estreses abióticos alteran la actividad de las enzimas sacarolíticas que controlan las relaciones fuente-sumidero, reduciendo el transporte de sacarosa y su utilización en los órganos sumidero y afectando, al crecimiento y la productividad de los cultivos. El objetivo de este trabajo fue estudiar la modulación de la actividad sacarolítica mediada por el portainjerto en frutos de plantas de pimiento sometidas a estrés salino. Los frutos de plantas injertadas sobre el portainjerto Creonte presentaron los valores más altos de sacarosa sintasa, invertasa vacuolar y de pared celular con respecto a las otras combinaciones y las plantas sin injertar, lo que podría explicar su mayor tasa reproductiva. Además, los frutos de plantas injertadas sobre Atlante y Terrano presentaron una mayor actividad de la invertasa citoplasmática, relacionada con su mayor tasa de crecimiento. Por tanto, el portainjerto modula las relaciones fuente-sumidero en condiciones de salinidad a través del incremento de las enzimas sacarolíticas. [ENG] Abiotic stresses alter the activity of saccharolytic enzymes that control source-sink relationships, reducing sucrose transport and utilization in sink organs and affecting crop growth and productivity. The objective of this work was to study the modulation of sucrolytic activity mediated by the rootstock in fruits of pepper plants subjected to salt stress. Fruits from plants grafted on the rootstock Creonte presented the highest values of sucrose synthase, vacuolar invertase and cell wall invertase with respect to the other combinations and ungrafted plants, which could explain their higher reproductive rate. In addition, fruits from plants grafted onto Atlante and Terrano presented higher cytoplasmic invertase activity, related to their higher growth rate. Therefore, the rootstock modulates source-sink relationships under salinity conditions through the increase of sucrolytic enzymes

Interaction between ABA and cytokinins in salinized tomato plants

Abscisic acid (ABA) and cytokinins (CKs) are phytohormones that mediate plant responses to abiotic stress and are mainly considered to be produced in roots. These two plant hormones have long been considered antagonists, but the role of this antagonism in mediating abiotic stress resistance remains unknown. In this study we have used reciprocal grafting of transgenic lines with altered hormone synthesis (ABA or CK synthesis) with the aim of assessing the importance of ABA and CK interaction in mediating plant salinity responses in tomato. Preliminary results have shown a negative effect in ABA and CK on tomato plant biomass under salinity. Results have also indicated that jasmonic acid (JA) might be involved in the negative impact on tomato growth caused by ABA and CK interaction under salt conditions.The authors thank Andrew J. Thompson, from Cranfield Univertity (UK), and Ann C. Smigocki from Molecular Plant Pathology Laboratory (EEUU) the NCED and IPT seeds sets respectively. This work was supported by CICYT AGL2011‐27996 and ROOTOPOWER (REF: 289365. FP7‐KBBE‐2011‐5 European Union)

Efectos de la sobreproducción de ácido abscísico y citoquininas en la respuesta fisiológica y agronómica de tomate bajo estrés salino en invernadero

La salinidad limita la productividad de los cultivos y modifica el balance hormonal vegetal. El ácido abscísico (ABA) y las citoquininas (CKs) son fitohormonas que median la respuesta a estreses abióticos y se considera que son producidas principalmente en la raíz. Para evaluar el papel de estas dos hormonas en el crecimiento y productividad de los cultivos bajo salinidad, se realizaron injertos cuyo portainjerto eran unas variedades transgénicas de tomate que sobreproducían ácido abscísico (ABA) (líneas NCED) y citoquininas (líneas IPT), utilizando una variedad comercial de tomate cherry como injerto. Las plantas de tomate injertadas fueron cultivadas en un invernadero comercial durante 6 meses en condiciones de salinidad moderada. Las plantas cuyo portainjerto era una variedad transgénica eran más vigorosas y presentaban mayor producción que las que tenían como portainjerto una planta wild type o la propia parte aérea injertada. Los análisis hormonales no explican completamente estos datos, por lo que otros tipos de análisis (genéticos, enzimáticos) son necesarios para explicar completamente estos datos.Los autores de la presente comunicación desean agradecer a Andrew J. Thompson de la Universidad de Cranfield (Reino Unido) y a Ann C. Smigocki del Molecular Plant Pathology Laboratory (EEUU) por los sets de semillas NCED e IPT respectivamente. Este trabajo ha sido financiado por CICYT AGL2011‐27996 y ROOTOPOWER (REF: 289365. FP7‐KBBE‐2011‐5 European Union

Root ABA signalling in salinized tomato

[SPA] Con el fin de comprender la influencia de la fitohormona ácido abscísico (ABA) en la adaptación al riego salino, dos líneas transgénicas independientes de tomate (Solanum lycopersicum L.), sp12 y sp5, que sobreexpresan constitutivamente el gen NCED1 (codifica para la enzima que cataliza un paso limitante en la biosíntesis de ABA) y la variedad silvestre Ailsa Craig, se han estudiado en experimentos o bien i) como planta entera o ii) como portainjerto bajo condiciones control y de estrés salino. Aunque la expresión constitutiva de NCED disminuye el crecimiento bajo condiciones control, minimiza los efectos producidos por la sal (planta completa) y mejora significativamente el crecimiento cuando se usa como portainjerto. El análisis de la savia xilemática de raíz mostró que los fenotipos resultantes bajo las diferentes condiciones de cultivo eran difíciles de explicar en términos de sobreproducción de ABA. Para intentar explicar estos resultados se llevó a cabo un análisis de expresión de un conjunto de genes relacionados con hormonas y estrés mediante PCR cuantitativa, así como un estudio transcriptómico mediante microarrays en la raíz. Los resultados sugieren que la sobreexpresión de NCED parece alterar diversas rutas de señalización, derivando en una respuesta adaptativa al estrés que podría ayudar a explicar los fenotipos observados. [ENG] With the aim of better understanding the influence of the plan hormone abscisic acid (ABA) in adaptation to saline irrigation, two independent transgenic tomato (Solanum lycopersicum L.) lines, sp12 and sp5, overexpressing constitutively NCED1 (the enzyme that catalyzes a key rate-limiting step in ABA biosynthesis) and the wild type Ailsa Craig, have been studied in experiments either i) as whole plants or ii) as rootstocks under control and salinity conditions. While NCED overexpression penalizes growth under control conditions, it minimized the effect of salinity (whole plants) or significantly improved plant growth and yield when used as rootstocks. The analysis of the root xylem sap revealed that the phenotypes resulting under the different conditions were difficult to explain in terms of ABA overproduction. With the aim of explaining these results, the expression of a set of hormone and stress associated genes (analysed by real time PCR) as well as a transcriptomic analysis (by using one-color microarray) were performed in roots. The results suggest that NCED overexpression seems to alter several signalling pathways leading to stress adaptive responses that could help to explain the observed phenotypes.The authors thank Andrew J. Thompson from Cranfield University, the NCED seeds set. This work was supported by CICYT-FEDER (project AGL2011-27996) and European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289365(ROOTOPOWER project).. -2010-5 European Union)

ABA-overproduction response under salinity

[SPA] Con el fin de comprender la influencia de la fitohormona ácido abscísico (ABA) en la adaptación al riego salino, dos líneas transgénicas independientes de tomate (Solanum lycopersicum L.), sp12 y sp5, que sobreexpresan constitutivamente el gen NCED1 (codifica para la enzima que cataliza un paso limitante en la biosíntesis de ABA) y la variedad silvestre Ailsa Craig, se han estudiado en experimentos o bien i) como planta entera o ii) como portainjerto bajo condiciones control y de estrés salino. Aunque la expresión constitutiva de NCED disminuye el crecimiento bajo condiciones control, minimiza los efectos producidos por la sal (planta completa) y mejora significativamente el crecimiento cuando se usa como portainjerto. El análisis de la savia xilemática de raíz mostró que los fenotipos resultantes bajo las diferentes condiciones de cultivo eran difíciles de explicar en términos de sobreproducción de ABA. Para intentar explicar estos resultados se llevó a cabo un análisis de expresión de un conjunto de genes relacionados con hormonas y estrés mediante PCR cuantitativa, así como un estudio transcriptómico mediante microarrays en la raíz. Los resultados sugieren que la sobreexpresión de NCED parece alterar diversas rutas de señalización, derivando en una respuesta adaptativa al estrés que podría ayudar a explicar los fenotipos observados. [ENG] With the aim of better understanding the influence of the plan hormone abscisic acid (ABA) in adaptation to saline irrigation, two independent transgenic tomato (Solanum lycopersicum L.) lines, sp12 and sp5, overexpressing constitutively NCED1 (the enzyme that catalyzes a key rate-limiting step in ABA biosynthesis) and the wild type Ailsa Craig, have been studied in experiments either i) as whole plants or ii) as rootstocks under control and salinity conditions. While NCED overexpression penalizes growth under control conditions, it minimized the effect of salinity (whole plants) or significantly improved plant growth and yield when used as rootstocks. The analysis of the root xylem sap revealed that the phenotypes resulting under the different conditions were difficult to explain in terms of ABA overproduction. With the aim of explaining these results, the expression of a set of hormone and stress associated genes (analysed by real time PCR) as well as a transcriptomic analysis (by using one-color microarray) were performed in roots. The results suggest that NCED overexpression seems to alter several signalling pathways leading to stress adaptive responses that could help to explain the observed phenotypes.The authors thank Andrew J. Thompson from Cranfield University, the NCED seeds set. This work was supported by CICYT-FEDER (project AGL2011-27996) and European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289365(ROOTOPOWER project)

Does high-intensity light pre-treatment improve drought response in Thymus zygis ssp. gracilis?

Global concern regarding climate change is prompting the development of strategies to improve the resistance of plants to abiotic stresses. Drought is one of the main threats that affect the productivity of rainfed crops, such as T. zygis ssp. gracilis. Plants under stressful conditions may generate a “memory” that allows them to cope more effectively with future stress. Thus, the objective of this study was to determine whether the pre-treatment of thyme with high-intensity light-emitting diode light (light priming) could enhance its physiological response and activation of its antioxidant defense system to subsequent severe drought. To that end, physiological parameters including relative water content, and proline and abscisic acid levels, photosynthetic pigment and tocochromanols content, phenolic profiles, antioxidant capacity, and lipid peroxidation were quantified using 1600 clones from 20 ecotypes. Results confirmed the negative effect of drought on overall plant status, but also showed a positive effect of light priming, this improved the antioxidant system response in around of 70 % of ecotypes of red thyme. Specifically, light pre-treatment was associated with smaller reduction in content of photosynthetic pigments and tocochromanols, higher caffeic acid dimethyl ether content, and reduced lipid peroxidation in response to drought. Light priming may generate a “memory” that helps thyme overcome subsequent oxidative stress

Effects of Auxin (Indole-3-butyric Acid) on Adventitious Root Formation in Peach-Based Prunus Rootstocks

18 Pags.- 5 Figs.- 3 Tabls. © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license.Several Prunus species are among the most important cultivated stone fruits in the Mediterranean region, and there is an urgent need to obtain rootstocks with specific adaptations to challenging environmental conditions. The development of adventitious roots (ARs) is an evolutionary mechanism of high relevance for stress tolerance, which has led to the development of environmentally resilient plants. As a first step towards understanding the genetic determinants involved in AR formation in Prunus sp., we evaluated the rooting of hardwood cuttings from five Prunus rootstocks (Adafuel, Adarcias, Cadaman, Garnem, and GF 677) grown in hydroponics. We found that auxin-induced callus and rooting responses were strongly genotype-dependent. To investigate the molecular mechanisms involved in these differential responses, we performed a time-series study of AR formation in two rootstocks with contrasting rooting performance, Garnem and GF 677, by culturing in vitro microcuttings with and without auxin treatment (0.9 mg/L of indole-3-butyric acid [IBA]). Despite showing a similar histological structure, Garnem and GF677 rootstocks displayed dynamic changes in endogenous hormone homeostasis involving metabolites such as indole-3-acetic acid (IAA) conjugated to aspartic acid (IAA-Asp), and these changes could explain the differences observed during rooting.This research received no external funding. M.M. is a research fellow of the Generalitat Valenciana (GRISOLIAP/2019/098).Peer reviewe