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The interest in natural sources with high antioxidant powder has recently increased in several sectors. Ionic gelation methods could be used to protect bioactive substances to control the kinetics and release of these ingredients to the food matrix. This study dealt with the evaluation of the antioxidant capacity and scavenging activity of extracts of Hibiscus Sabdariffa L. (HSL) (with 50% ethanol) encapsulated in calcium alginate spheres as a new source for preserving food against oxidative damage. Their antioxidant activity was measured in different o/w emulsions in which HSL spheres reduced the formation of hydroperoxides (~80%) and thiobarbituric-acid-reactive substance products (~20%). The scavenging activity of HSL extracts was measured in different food simulants (water, water acidified with 3% acetic acid, ethanol at 50%, and pure ethanol), and corresponded to 0.20–0.43, 0.31–0.62, and 11.13–23.82 mmol Trolox/mL extract for Trolox equivalent antioxidant capacity (TEAC), 2,2-diphenylpicrylhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC) assays, respectively. In general, the best antiradical activity was observed in the ethanolic and acidified mediums, in which the highest concentration of released polyphenols ranged from 0.068 to 0.079 mg GAE/mL. This work indicates the potential of alginate spheres for encapsulating antioxidant compounds as an innovative strategy for several industrial applications., Peer Reviewed, Postprint (published version)

Trace metals are essential elements that play key roles in a number of biochemical processes governing human visual physiology in health and disease. Several trace metals, such as zinc, have been shown to play important roles in the visual phototransduction process. In spite of this, there has been little research conducted on the direct effect of trace metal elements on the visual photoreceptor rhodopsin. In the current study, we have determined the effect of several metal ions, such as iron, copper, chromium, manganese, and nickel, on the conformational stability of rhodopsin. To this aim, we analyzed, by means of UV-visible and fluorescence spectroscopic methods, the effects of these trace elements on the thermal stability of dark rhodopsin, the stability of its active Metarhodopsin II conformation, and its chromophore regeneration. Our results show that copper prevented rhodopsin regeneration and slowed down the retinal release process after illumination. In turn, Fe3+, but not Fe2+, increased the thermal stability of the dark inactive conformation of rhodopsin, whereas copper ions markedly decreased it. These findings stress the important role of trace metals in retinal physiology at the photoreceptor level and may be useful for the development of novel therapeutic strategies to treat retinal disease., This research was funded by grants from Ministry of Science and Innovation, Spain (PID2019-104817GB-I00), and from the Government of Catalonia to Research Consolidated Groups (2021 SGR 00342) to P.G. F.W. is the recipient of a predoctoral grant from the Secretariat for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia and the European Social Fund (2021 FI_B 00228)., Peer Reviewed, Postprint (published version)

Sentinel-2 offers great potential for monitoring water quality in inland and coastal waters. However, atmospheric correction in these waters is challenging, and there is no standardized approach yet, but different methods coexist under constant development. The atmospheric correction Case 2 Regional Coast Colour (C2RCC) processor has been recently updated with the C2X-COMPLEX (C2XC). This study is one of the first attempts at exploring its performance, in comparison with C2RCC and C2X, in inland and coastal waters in the east of the Iberian Peninsula, in retrieving water surface reflectance and estimating chlorophyll-a ([Chl-a]), total suspended matter ([TSM]), and Secchi disk depth (ZSD). The relationship between in situ ZSD and Kd_z90max product (i.e., the depth of the water column from which 90% of the water-leaving irradiance is derived) of the C2RCC processors demonstrated the potential of this product for estimating water clarity (r > 0.75). However, [TSM] and [Chl-a] derived from the different processors with default calibration factors were not suitable within the targeted scenarios, requiring recalibration based on optical water types or a shift to dynamic algorithm blending approaches. This would benefit from switching between C2RCC and C2XC, which extends the potential for improving surface reflectance estimates to a wide range of scenarios and suggests a promising future for C2-Nets in operational monitoring of water quality., Jesús Soriano held a pre-doctoral grant funded by Agència de Gestió d’Ajuts Universitaris i de Recerca (2020FI_B2 00148). Esther Patricia Urrego holds a pre-doctoral grant funded by Ministerio de Ciencia, Innovación y Universidades (PRE2019-088232). This research was partially funded by the European Union—ERDF and the Ministry of Science and Innovation and the State Research Agency of Spain under project RTI2018-098651-B-C51 (FLEXL3L4—Advanced Products L3 and L4 for the FLEX-S3 mission)., Peer Reviewed, Postprint (published version)

Proximal remote sensing devices are novel tools that enable the study of plant health status through the measurement of specific characteristics, including the color or spectrum of light reflected or transmitted by the leaves or the canopy. The aim of this study is to compare the RGB and multispectral data collected during five years (2016–2020) of four fruiting vegetables (melon, tomato, eggplant, and peppers) with trial treatments of non-grafted and grafted onto resistant rootstocks cultivated in a Meloidogyne incognita (a root-knot nematode) infested soil in a greenhouse. The proximal remote sensing of plant health status data collected was divided into three levels. Firstly, leaf level pigments were measured using two different handheld sensors (SPAD and Dualex). Secondly, canopy vigor and biomass were assessed using vegetation indices derived from RGB images and the Normalized Difference Vegetation Index (NDVI) measured with a portable spectroradiometer (Greenseeker). Third, we assessed plant level water stress, as a consequence of the root damage by nematodes, using stomatal conductance measured with a porometer and indirectly using plant temperature with an infrared thermometer, and also the stable carbon isotope composition of leaf dry matter.. It was found that the interaction between treatments and crops (ANOVA) was statistically different for only four of seventeen parameters: flavonoid (p < 0.05), NBI (p < 0.05), NDVI (p < 0.05) and the RGB CSI (Crop Senescence Index) (p < 0.05). Concerning the effect of treatments across all crops, differences existed only in two parameters, which were flavonoid (p < 0.05) and CSI (p < 0.001). Grafted plants contained fewer flavonoids (x¯ = 1.37) and showed lower CSI (x¯ = 11.65) than non-grafted plants (x¯ = 1.98 and x¯ = 17.28, respectively, p < 0.05 and p < 0.05) when combining all five years and four crops. We conclude that the grafted plants were less stressed and more protected against nematode attack. Leaf flavon, Y.H. acknowledges the support of the Tunisian government from the Ministery of Higher Education and Scientific Research. J.L.A. acknowledges support from the Institució Catalana d’Investigació i Estudis Avançats (ICREA) Academia, Generalitat de Catalunya, Spain. S.C.K. is supported by the Ramon y Cajal RYC-2019-027818-I research fellowship from the Ministerio de Ciencia e Innovación, Spain. Thanks are also given to the Spanish Ministry of Economy and Competitiveness (MINECO) and the European Regional Development Fund (FEDER) for funding the project AGL2013-49040-C2-1-R and to the Ministry of Science and Innovation from the Spanish Government for funding the AGL2017-89785-R, and to the European Regional Development Fund (FEDER) AGL2017-89785-R, and for providing the FPI grant PRE2018-084265 to AMF. This research was also supported by the COST Action CA17134 SENSECO (Optical synergies for spatiotemporal sensing of scalable ecophysiological traits) funded by COST (European Cooperation in Science and Technology, www.cost.eu accessed on 29 April 2022)., Postprint (published version)

Canopy characterisation is a key factor for the success and efficiency of the pesticide application process in vineyards., This research was developed with partial funding from the FI-AGAUR grant from the Generalitat de Catalunya (2017 FI_B 00893, Preprint

During air-assisted spraying operations in orchards, the interaction between the droplets and the target leaves has a decisive influence on the retention of the droplets on the leaves and the final deposition state. Based on the observation of the final deposition effect of the droplets in the spray test, the retention state of the droplets on the leaves is divided into three categories: uniform distribution (hereinafter referred to as uniform), accumulation, and loss. During the initial interaction between the droplets and the leaves, the adhesion or sliding state of the droplets has an important influence on the final deposition state of the droplets, which is determined by the target leaf adhesion work in this paper. Based on obtaining the characteristic parameters of the leaf surface, a theoretical model of adhesion work related to parameters such as the contact angle, rough factor, and initial ilt angle of the leaf is established. Afterward, through the connection of the droplet coverage on the macro level, the establishment of the deposition state model of the droplet group on the leaf is completed. By conducting the experiment test based on the Box-Behnken design of response surface methodology (RSM), the droplet deposition states under the influence of the spray distance, fan outlet wind speed and droplet size were studied and compared with the predicted values. The test results show that the prediction accuracies of the three states of uniform, accumulation, and loss were 87.5%, 80%, and 100%, respectively. The results of the study indicate that the established prediction model can effectively predict the deposition states of droplets on leaves and provide a reference for the selection of spray operation parameters., Peer Reviewed, Postprint (published version)

The dramatic reduction in the diversity of crops in the last century is often attributed to the consolidation of scientific breeding, probably because the two processes have occurred at the same time. We carried out a breeding program to enhance the Castellfollit del Boix landrace of common bean (Phaseolus vulgaris L.) in a low-input environment to determine the effects of breeding on a landrace at risk of disappearing. The program increased the number of accessions conserved ex situ and obtained more efficient genotypes that are less likely to be abandoned by farmer without altering the characteristics that consumers appreciate most. As a result, the availability of the product, its promotion, and its use have increased, Postprint (published version)

Shellfish aquaculture has a major socioeconomic impact on coastal areas, thus it is necessary to develop support tools for its management. In this sense, phytoplankton monitoring is crucial, as it is the main source of food for shellfish farming. The aim of this study was to assess the applicability of Sentinel 2 multispectral imagery (MSI) to monitor the phytoplankton biomass at Ebro Delta bays and to assess its potential as a tool for shellfish management. In situ chlorophyll-a data from Ebro Delta bays (NE Spain) were coupled with several band combination and band ratio spectral indices derived from Sentinel 2A levels 1C and 2A for time-series mapping. The best results (AIC = 72.17, APD < 10%, and MAE < 0.7 mg/m3) were obtained with a simple blue-to-green ratio applied over Rayleigh from Sentinel 2A levels 1C and 2A for time-series mapping. The best results (AIC = 72.17, APD < 10%, and MAE < 0.7 mg/m3) were obtained with a simple blue-to-green ratio applied over Rayleigh corrected images. Sentinel 2–derived maps provided coverage of the farm sites at both bays allowing relating the spatiotemporal distribution of phytoplankton with the environmental forcing under different states of the bays. The applied methodology will be further improved but the results show the potential of using Sentinel 2 MSI imagery as a tool for assessing phytoplankton spatiotemporal dynamics and to encourage better future practices in the management of the aquaculture in Ebro, Peer Reviewed, Postprint (published version)

Although consumers appreciate the genetic diversity among tomato landraces, traditional varieties have been displaced from commercial agriculture. Their cultivation through organic farming in natural parks can contribute to their resurgence. With this aim, we developed a participatory plant breeding (PPB) program in Collserola Natural Park (Barcelona, Spain) to promote the conservation of the Mando landrace and to obtain new varieties adapted to local organic farms, Postprint (published version)