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Plants have a large number of bioactive compounds with high antioxidant activity. Studies for the determination of the antioxidant activity of different plant species could contribute to revealing the value of these species as a source of new antioxidant compounds. There is a large variety of in vitro methods to quantify antioxidant activity, and it is important to select the proper method to determine which species have the highest antioxidant activity. The aim of this work was to verify whether different methods show the same sensitivity and/or capacity to discriminate the antioxidant activity of the extract of different plant species. To that end, we selected 12 species with different content of phenolic compounds. Their extracts were analyzed using the following methods: 2,2-di-phenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay, ferric reducing (FRAP) assay, Trolox equivalent antioxidant capacity (ABTS) assay, and reducing power (RP) assay. The four methods selected could quantify the antioxidant capacity of the 12 study species, although there were differences between them. The antioxidant activity values quantified through DPPH and RP were higher than the ones obtained by ABTS and FRAP, and these values varied among species. Thus, the hierarchization or categorization of these species was different depending on the method used. Another difference established between these methods was the sensitivity obtained with each of them. A cluster revealed that RP established the largest number of groups at the shortest distance from the root. Therefore, as it showed the best discrimination of differences and/or similarities between species, RP is considered in this study as the one with the highest sensitivity among the four studied methods. On the other hand, ABTS showed the lowest sensitivity. These results show the importance of selecting the proper antioxidant activity quantification method for establishing a ranking of species based on this parameter.

is project received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement nos. 721995 and 749323. The authors acknowledge the Alexander von Humboldt Founda tion for supporting this research with the Max-Planck Prize to Markus Reichstein. We also acknowledge the European Space Agency (ESA) in the frame of the FLEXSense campaign (ESA contract no. 4000125402/18/NL/NA) and the Photoproxy cam paign (ESA contract no. 4000125731/19/NL/LF). MMigliavacca and GWohlfahrt acknowledge funding from the joint FWF DFG DACH project ‘Constraining terrestrial gross primary pro ductivity by joint measurements of the carbonyl sulfide exchange and sun-induced fluorescence’. GWohlfahrt further acknowl edges financial support by the AustroSIF project, which is funded by the FFG and BMK within the Austrian Space Applications Programme. Open access funding enabled and organised by ProjektDEAL.

La resina de ládano o \"goma\" se puede obtener de Cistus ladanifer L. mediante dos métodos de extracción diferentes: el proceso zamoreño y el andaluz. Aunque su uso principal es en los sectores de fragancias y perfumería, los informes etnobotánicos describen su uso con fines medicinales en el manejo de la hiperglucemia y las enfermedades mentales. Sin embargo, los datos relativos a las bioactividades y aplicaciones farmacológicas son escasos. En este trabajo se comprobó que el rendimiento de la resina de ládano extraída por el proceso andaluz era 25 veces superior al de la zamoreña. Ambas resinas se purificaron como absolutos, y el absoluto andaluz se purificó en fracciones diterpenoides y flavonoides. El análisis de GC-EI-MS confirmó la presencia de fenilpropanoides, diterpenoides tipo ládano y flavonoides metilados, que ya están descritos en la literatura, pero revelaron otros compuestos, y mostraron que los diferentes extractos presentaban un perfil químico distinto. Se investigó la potencial actividad antidiabética, por inhibición de la α-amilasa y la α-glucosidasa, y la potencial actividad neuroprotectora, por inhibición de la acetilcolinesterasa. La fracción diterpenoide produjo el mayor efecto inhibidor de la α-amilasa (~30% y ~40% a 0,5 y 1 mg/mL, respectivamente). El absoluto de zamoré mostró el mayor efecto inhibidor de la α-glucosidasa (~14% y ~24%, a 0,5 y 1 mg/mL, respectivamente). El absoluto de Andalucía mostró el mayor efecto inhibidor de la acetilcolinesterasa (~70% y ~75%, a 0,5 y 1 mg/mL, respectivamente). Utilizando las líneas celulares Caco-2 y HepG2, el absoluto de Andalucía y sus fracciones purificadas mostraron una actividad citotóxica/antiproliferativa moderada a las 24 h de exposición (IC50 = 45–70 μg/mL, para Caco-2; IC50 = 60-80 μg/mL, para HepG2), mientras que el absoluto de zamoreña no produjo citotoxicidad (IC50 ≥ 200,00 μg/mL). Aquí mostramos, por primera vez, que la resina de ládano obtenida por el proceso andaluz, y sus fracciones, están compuestas por fitoquímicos con potencial antidiabético, neuroprotector y antiproliferativo, que merecen ser investigados para la industria farmacéutica. Sin embargo, los efectos secundarios tóxicos también deben abordarse cuando se utilizan estos productos por ingestión, como se hace tradicionalmente.

Los “sandstone mounds” o monticulos arenosos (sensu Bradshaw en Sedimentology 7:149–154, 1966) son estructuras sedimentarias formadas por erosión de fluidos sobre arenas. Consisten en sistemas de montículos, crestas y depresiones de forma variada, preservados en la parte superior de las capas de arenisca. En este estudio se describen “sandstone mounds” en la Formación Cuarcita Armoricana y en las Capas de Marjaliza, Extremadura, y en la Formación Pochico de Ciudad Real. Son las primeras citas de estas estructuras en el Ordovícico de la Zona Centroibérica, suroeste de España, añadiéndose al escaso registro global de estas estructuras sedimentaria. Una revisión bibliográfica revela que no existen citas de “sandstone mounds” en rocas más modernas que el Devónico y que la mayoría proceden de rocas ordovícicas situadas en el margen gondwánico del Océano Reico. Es probable que existan “sandstone mounds” en rocas más modernas, aunque cambios seculares en las propiedades de los sedimentos y una configuración favorable de la plataforma podrían ser explicaciones alternativas para este patrón.

Major cereal yields are expected to decline significantly in coming years due to the effects of climate change temperature rise. Agroforestry systems have been recognized as a useful land management strategy that could mitigate these effects through the shelter provided by trees, but it is unclear how shade affects cereal production. Most cereal species and cultivars have been selected for full light conditions, making it necessary to determine those able to acclimate to low irradiance environments and the traits that drive this acclimation. A greenhouse experiment was conducted in central Spain to assess the photosynthetic response, leaf morphology and grain yield of nine cultivars of winter wheat (“Triticum aestivum” L.) and barley (“Hordeum vulgare” L.) at three levels of photosynthetic active radiation (100%, 90% and 50%). Cultivars were selected according to three different precocity categories and were widely used in the studied area. The main objective was to assess whether the species and cultivars could acclimate to partial shade through physiological and morphological acclimations and thus increase their grain yield for cultivation in agroforestry systems. Both species increased grain yield by 19% in shade conditions. However, they used different acclimation strategies. Barley mostly performed a physiological acclimation, while wheat had a major morphological adjustment under shaded environment. Barley had lower dark respiration (42%), lower light compensation point (73%) and higher maximum quantum yield (48%) than wheat in full light conditions, revealing that it was a more shade-tolerant species than wheat. In addition, to acclimate to low irradiance conditions, barley showed a 21% reduction of the carotenoids/chlorophyll ratio in the lowest irradiance level compared to 100% light availability and adjusted the chlorophyll a/b ratio, photosystem II quantum efficiency, electron transport rate and non-photochemical quenching to shade conditions. On the other hand, wheat showed a 48% increase in single leaf area in the 50% irradiance level than in full light to maximize light capture. Our results showed that current commercialized wheat and barley cultivars had sufficient plasticity for adaptation to shade, supporting tree presence as a tool to reduce the negative effects of climate change.

Variability in population densities is key to the ecology of natural systems but also has great implications for agriculture. Farmers’ decisions are heavily influenced by their risk aversion to pest outbreaks that result in major yield losses. However, the need for long-term pest population data across many farms has prevented researchers from exploring the drivers and implications of pest population variability (PV). Here, we demonstrate the critical importance of PV for sustainable farming by analyzing 13 years of pest densities across >1300 Spanish olive groves and vineyards. Variable populations were more likely to cause major yield losses, but also occasionally created temporal windows when densities fell below insecticide spray thresholds. Importantly, environmental factors regulating pest variability were very distinct from factors regulating mean density, suggesting variability needs to be uniquely managed. Finally, we found diversifying landscapes may be a win–win situation for conservation and farmers, as diversified landscapes promote less abundant and less variable pest populations. Therefore, we encourage agricultural stakeholders to increase the complexity of the landscapes surrounding their farms through conserving/restoring natural habitat and/or diversifying crops.

This work was funded by the Marie Curie ITN ‘NEPTUNE’ grant (no. 317172), under FP7 of the European Commission, Sören Jensen acknowledges funding from project CGL 2017–87631-P from Spanish MINECO. The experimental work at University Marine Biological Station, Millport, Scotland, was funded by NERC grant GR3/10713 to Simon Conway Morris

Auxin is essential for the regulation of root system architecture by controlling primary root elongation and lateral root (LR) formation. Exogenous auxin has been reported to inhibit primary root elongation and promote the formation of LRs. In this study, LR formation in the primary root was quantitatively evaluated after exogenous auxin treatment by comparing the effects of auxin on two selected zones elongated either before or after auxin application. We determined two main variables in both zones: the LR density per unit of root length (LRD), and the mean phloem pericycle cell length. The total number of phloem pericycle cells (PPCs) per unit of root length was then calculated. Considering that each LR primordium is initiated from four founder cells (FCs), the percentage of PPCs (%PPC) that behave as FCs in a specific root zone was estimated by dividing the number of pericycle cells by four times the LRD. This index was utilized to describe LR initiation. Root zones elongated in the presence of a synthetic auxin (1-naphthalene acetic acid, NAA) at low concentrations (0.01 μM) showed reduced cell length and increased LRD. However, a high concentration of NAA (0.1 μM) strongly reduced both cell length and LRD. In contrast, both low and high levels of NAA stimulated LRD in zones elongated before auxin application. Analysis of the percentage of FCs in the phloem pericycle in zones elongated in the presence or absence of NAA showed that low concentrations of NAA increased the %PFC, indicating that LR initiation is promoted at new sites; however, high concentrations of NAA elicited a considerable reduction in this variable in zones developed in the presence of auxin. As these zones are composed of short pericycle cells, we propose that short pericycle cells are incapable to participate in LR primordium initiation and that auxin modulated initiation of LRs is linked to pericycle cell length.

All the financial support has been received by professor Jose Carlos García-Gómez and any funder have influence in the research. The details are: - JCGG (68/83 / 4081/0171) Organization of American States (https://www.oas.org/en/). - JCGG (68/83 / 4358/0171) Autoridad Portuaria de Sevilla (https://www.puertodesevilla.com/). - JCGG (68/83 / 3850/0171) Diputación Provincial de Cádiz (https://www.dipucadiz.es/). - JCGG (PRJ201903535) Fundación CEPSA (https://www.cepsa.com/es/). - JCGG (68/83 / 3608/0171) Fundación ENDESA (https://www.endesa.com/es). - JCGG (PRJ201903717) Red Eléctrica de España (https://www.ree.es/es).

The root system is responsible for water and nutrients uptake from the soil, and therefore, its extension is basic for an efficient acquisition. The maize root system is formed by different types of roots, and the lateral root branching substantially increases the surface for nutrient uptake. Therefore, the regulation of lateral root formation is fundamental in the development of root functions. Root architecture is basically controlled by auxin and cytokinins, which antagonize in the formation of lateral roots (LR) along the primary root axis, with auxin, a stimulator, and cytokinins inhibitors of LR development. This interaction has been analyzed in several zones along the primary root where LRs in different developmental stages were located. The root has been divided into several zones, such as meristem, elongation zone, and mature zone, according to the developmental processes occurring in each one. As Arabidopsis root elongated more slowly than maize root, these zones are shorter, and its delimitation is more difficult. However, these zones have previously been delimitated clearly in maize, and therefore, they analyze the effect of exogenous hormones in several LR developmental stages. The inhibitory effect of cytokinin on lateral root formation was observed in already elongated primary root zones in which initial events to form new lateral roots are taking place. Contrarily, auxin increased LR formation in the primary root segments elongated in the presence of the hormone. The inhibitory effect of cytokinin was reversed by auxin in a concentration-dependent manner when both hormones were combined. However, auxin is unable to recover LR development in primary root zones that have been previously elongated only in the presence of cytokinin. This antagonistic auxin-cytokinin effect on LR development depended on the balance between both hormones, which controls the root system architecture and determines the formation of LR during the process of initiation.