Agrotecnio Center

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https://repositori.udl.cat/handle/10459.1/56965

Agrotecnio aims to become a reference in Europe addressing all the key elements of the food production chain in an integrated way focusing on target crops and animals of commercial importance, rather than model systems. This later aspect sets our centre apart from other centers which focus on fundamental science and/or model plant and animal systems. As a result we should be able to address fundamental and important questions in the crop/animal of interest and results from our research will be directly and immediately applicable to our target organism. [Més informació]

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Open Access
3D characterization of a Boston Ivy double-skin green building facade using a LiDAR system
(Elsevier, 2021-09-02) Pérez Luque, Gabriel; Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon; Coma Arpón, Julià; Arasanz Riba, Roger; Marrero Farré, Bernat; Cabeza, Luisa F.; Gregorio López, Eduard
On the way to more sustainable and resilient urban environments, the incorporation of urban green infrastructure (UGI) systems, such as green roofs and vertical greening systems, must be encouraged. Unfortunately, given their variable nature, these nature-based systems are difficult to geometrically characterize, and therefore there is a lack of 3D objects that adequately reflect their geometry and analytical properties to be used in design processes based on Building Information Modelling (BIM) technologies. This fact can be a disadvantage, during the building's design phase, of UGIs over traditional grey solutions. Areas of knowledge such as precision agriculture, have developed technologies and methodologies that characterize the geometry of vegetation using point cloud capture. The main aim of this research was to create the 3D characterization of an experimental double-skin green facade, using LiDAR technologies. From the results it could be confirmed that the methodology used was precise and robust, enabling the 3D reconstruction of the green facade's outer envelope. Detailed results were that foliage volume differences in height were linked to plant growth, whereas differences in the horizontal distribution of greenery were related to the influence of the local microclimate and specific plant diseases on the south orientation. From this research, along with complementary previous research, it could be concluded that, generally speaking, with vegetation volumes of 0.2 m3/m2, using Boston Ivy (Parthenocissus Tricuspidata) under Mediterranean climate, reductions in external building surface temperatures of around 13 °C can be obtained and used as analytic parameter in a future 3D-BIM-object.
Open Access
3D Spectral Graph Wavelet Point Signatures in Pre-Processing Stage for Mobile Laser Scanning Point Cloud Registration in Unstructured Orchard Environments
(Institute of Electrical and Electronics Engineers, 2021-11-18) Guevara, Javier; Gené Mola, Jordi; Gregorio López, Eduard; Auat Cheein, Fernando A.
The use of three-dimensional registration techniques is an important component for sensor-based localization and mapping. Several approaches have been proposed to align three-dimensional data, obtaining meaningful results in structured scenarios. However, the increased use of high-frame-rate 3D sensors has lead to more challenging application scenarios here the performance of registration techniques may degrade significantly. In order to improve the accuracy of the procedure, different works have considered a representative subset of points while preserving application-dependent features for registration. In this work, we tackle such a problem, considering the use of a general feature-extraction operator in the spectral domain as a prior step to the registration. The proposed spectral strategies use three wavelet transforms that are evaluated along with four well-known registration techniques. The methodology was experimentally validated in a dense orchard environment. The results show that the probability of failure in registration can be reduced up to 12.04% for the evaluated approaches, leading to a significant increase in the localization accuracy. Those results validate the effectiveness and efficiency of the spectral-assisted registration algorithms in an agricultural setting and motivate their usage for a wider range of applications.
Open Access
A 'Wiring Diagram' for sink-strength traits impacting wheat yield potential
(Oxford University Press, 2022-11-08) Slafer, Gustavo A.; Foulkes, M. John; Reynolds, Matthew P.; Murchie, Erik; Carmo-Silva, Elizabete; Flavell, Richard B.; Gwyn, Jeff; Sawkins, Mark; Griffiths, Simon
Identifying traits for improving sink-strength is a bottleneck to increasing wheat yield. The interacting processes determining sink-strength and yield potential are reviewed and visualized in a set of 'Wiring Diagrams', covering critical phases of development (and summarizing known underlying genetics). Using this framework, we reviewed and assembled the main traits determining sink-strength and identified research gaps and potential hypotheses to be tested for achieving gains in sink-strength. In pre-anthesis grain number could be increased through: (i) enhanced spike growth associated with optimized floret development and/or a reduction in specific stem-internode lengths and (ii) improved fruiting efficiency through accelerated rate of floret development, improved partitioning between spike or optimized spike cytokinin levels. In post-anthesis grain sink-strength could be augmented through manipulation of grain size potential via ovary size and/or endosperm cell division and expansion. Prospects for improving spike vascular architecture to support all rapidly growing florets, enabling the improved flow of assimilate, are also discussed. Finally, we considered the prospects for enhancing grain weight realization in relation to genetic variation in stay-green traits as well as stem carbohydrate remobilization. The Wiring Diagrams provide a potential workspace for breeders and crop scientists to achieve yield gains in wheat and other field crops.
Open Access
A bivalent dendrimeric peptide bearing a T-cell epitope from foot-and-mouth disease virus protein 3A improves humoral response against classical swine fever virus
(Elsevier, 2017) Bohórquez, José Alejandro; Defaus, Sira; Muñoz González, Sara; Perez-Simó, Marta; Rosell, Rosa; Fraile Sauce, Lorenzo José; Sobrino, Francisco; Andreu, David; Ganges, Llilianne
Three dendrimeric peptides were synthesized in order to evaluate their immunogenicity and their potential protection against classical swine fever virus (CSFV) in domestic pigs. Construct 1, an optimized version of a previously used dendrimer, had four copies of a B-cell epitope derived from CSFV E2 glycoprotein connected to an also CSFV-derived T-cell epitope through maleimide instead of thioether linkages. Construct 2 was similarly built but included only two copies of the B-cell epitope, and in also bivalent construct 3 the CSFV T-cell epitope was replaced by a previously described one from the 3A protein of foot-and-mouth disease virus (FMDV). Animals were inoculated twice with a 21-day interval and challenged 15days after the second immunization. Clinical signs were recorded daily and ELISA tests were performed to detect antibodies against specific peptide and E2. The neutralising antibody response was assessed 13days after challenge. Despite the change to maleimide connectivity, only partial protection against CSFV was again observed. The best clinical protection was observed in group 3. Animals inoculated with constructs 2 and 3 showed higher anti-peptide humoral response, suggesting that two copies of the B-cell epitope are sufficient or even better than four copies for swine immune recognition. In addition, for construct 3 higher neutralizing antibody titres against CSFV were detected. Our results support the immunogenicity of the CSFV B-cell epitope and the cooperative role of the FMDV 3A T-cell epitope in inducing a neutralising response against CSFV in domestic pigs. This is also the first time that the FMDV T-cell epitope shows effectivity in improving swine immune response against a different virus. Our findings highlight the relevance of dendrimeric peptides as a powerful tool for epitope characterization and antiviral strategies development.
Open Access
A carotenogenic mini-pathway introduced into white corn does not affect development or agronomic performance
(Nature, 2016) Zanga, Daniela; Capell Capell, Teresa; Slafer, Gustavo A.; Christou, Paul; Savin, Roxana
High-carotenoid corn (Carolight®) has been developed as a vehicle to deliver pro-vitamin A in the diet and thus address vitamin A deficiency in at-risk populations in developing countries. Like any other novel crop, the performance of Carolight® must be tested in different environments to ensure that optimal yields and productivity are maintained, particularly in this case to ensure that the engineered metabolic pathway does not attract a yield penalty. Here we compared the performance of Carolight® with its near isogenic white corn inbred parental line under greenhouse and field conditions, and monitored the stability of the introduced trait. We found that Carolight® was indistinguishable from its near isogenic line in terms of agronomic performance, particularly grain yield and its main components. We also established experimentally that the functionality of the introduced trait was indistinguishable when plants were grown in a controlled environment or in the field. Such thorough characterization under different agronomic conditions is rarely performed even for first-generation traits such as herbicide tolerance and pest resistance, and certainly not for complex second-generation traits such as the metabolic remodeling in the Carolight® variety. Our results therefore indicate that Carolight® can now be incorporated into breeding lines to generate hybrids with locally adapted varieties for further product development and assessment.
Open Access
A Cheap electronic sensor automated trap for monitoring the flight activity period of moths
(Institute of Entomology, 2021-10-11) Pérez Aparicio, Alicia; Llorens Calveras, Jordi; Rosell Polo, Joan Ramon; Martí, Jordi; Gemeno Marín, César
Automated pheromone dispensers disrupt the mating behaviour of pest moths by releasing pheromone during their daily activity period, which is not the same for all target species. These periods usually occur in or close to night time and last just a few hours, so automated sampling devices are needed to characterize them. However, the commercially available automated models do not provide enough temporal resolution for characterizing the short diel periods of sexual activity of moths. Thus, we built and tested a relatively cheap and simple high-temporal-resolution image-sensor insect trap. It consisted of a Raspberry Pi computer with an infrared camera operated by open-source software and housed in a plastic box. The Raspberry Pi was powered by a solar panel and rechargeable battery that were mounted on a solid and weather-proof structure made of cheap materials. Pictures were downloaded by WiFi from the Raspberry's SD card to a computer. Six traps baited either with synthetic sex pheromone or with females of Grapholita molesta (Busk) were tested in the field. The traps were sturdy, reliable and easy to use, taking pictures at 10 min intervals, 24 h a day for over two months. These pictures confirmed previous results regarding the period of sexual activity of the oriental fruit moth, which will aid in determining the optimal time for operating automated pheromone dispensers.
Open Access
A closer look at sex pheromone autodetection in the Oriental fruit moth
(Springer Nature, 2022) Pérez Aparicio, Alicia; Ammagarahalli Munishamappa, Byrappa; Gemeno Marín, César
Female moths emit sex pheromone to attracts males, and although they are not attracted to their own sex pheromone, they appear to detect it as it affects their behavior. In order to elucidate the mechanism of pheromone “autodetection” we compared responses of olfactory receptor neurons (ORNs) of male and female Grapholita molesta, a species with reported pheromone autodetection. Two concentrations of the major (Z8-12:Ac) and minor (E8-12:Ac) sex pheromone components, a plant-volatile blend containing methyl salicylate, terpinyl acetate and (E)-β-farnesene, and the male-produced hair-pencil (i.e., courtship) pheromone (ethyl trans-cinnamate) were tested in 45 male and 305 female ORNs. Hierarchical cluster analysis showed radically different peripheral olfactory systems between sexes that could be linked to their specific roles. In males 63% of the ORNs were tuned specifically to the major or minor female sex pheromone components, and 4% to the plant volatile blend, while the remaining 33% showed unspecific responses to the stimulus panel. In females 3% of the ORNs were specifically tuned to the male hair-pencil pheromone, 6% to the plant volatile blend, 91% were unspecific, and no ORN was tuned their own sex pheromone components. The lack of sex pheromone-specific ORNs in females suggests that they are not able to discriminate pheromone blends, and thus pheromone autodetection is unlikely in this species. We discuss our results in the context of the methodological limitations inherent to odor stimulation studies.
Open Access
A cow-calf farming system fully adapted to elevation and harsh conditions in Andorra (Europe)
(MDPI, 2021) Armengol Gelonch, Ramon; Bassols, Marta; Fraile Sauce, Lorenzo José
The use of natural resources is an important topic to optimize the efficiency of cattle production. The purpose of this work is to describe the project of the Bruna d'Andorra; a local cow breed under an extensive cow-calf system in Andorra (Europe), as an example of local farming and marketing of its meat products in an area with adverse environmental conditions. This breed is located in Andorra, a microstate that consists predominantly of rugged mountains and harsh weather conditions. The cow-calf Bruna d'Andorra extensive system is thoroughly described and productive and reproductive performance, compiled over 21 years (2000-2020), has been analyzed by years with the Chi-square test or ANOVA to compare proportions or means, respectively, and regression analysis was used to decipher evolution across years. The results show a population with a census large and stable enough to avoid inbreeding. Moreover, a sustained improvement of the productive performance and maternal fitness has been observed along the studied period for Bruna d'Andorra. The work concludes that local breeds can achieve sustainable animal production, especially when farmers, public administration and commercial circuits in the area agree to cooperate on such projects. The study also concludes that the Bruna d'Andorra cow breed can still improve in meat and reproductive performance.
Open Access
A decision support tool for assessing the impact of climate change on multiple ecosystem services
(MDPI, 2019-05-21) Cristal, Irina; Améztegui González, Aitor; González-Olabarria, José Ramón; Garcia Gonzalo, Jordi
In the climate change era, forest managers are challenged to use innovative tools to encourage a sustained provision of goods and services. Many decision support tools (DSTs), developed to address global changes in forest management practices, reflect the complexity of the scientific knowledge produced, a fact that could make it difficult for practitioners to understand and adopt them. Acknowledging the importance of knowledge transfer to forestry practitioners, this study describes a user-centric decision support software tool, aiming to assess forest management and climate change impacts on multiple ecosystem services (ESs) at a stand level. SORTIE-ND, a spatially explicit tree-level simulator for projecting stand dynamics that is sensitive to climate change, is encapsulated into the decision support tool and used as the simulation engine for stand development. Linking functions are implemented to evaluate ecosystem services and potential risks, and decision support is provided in form of interactive 2D and 3D visualizations. Five main components were identified to delineate the workflow and to shape the decision support tool: the information base, the alternative generator, the forest simulator, the ecosystem services calculator, and the visualization component. In order to improve the interaction design and general user satisfaction, the usability of the system was tested at an early stage of the development. While we have specifically focused on a management-oriented approach through user-centric interface design, the utilization of the product is likely to be of importance in facilitating education in the field of forest management.
Open Access
A fire spread simulator to support tactical management decisions for Mediterranean landscapes
(Frontiers, 2023) González-Olabarria, José Ramón; Carrasco, Jaime; Pais, Cristobal; Garcia Gonzalo, Jordi; Palacios-Meneses, David; Mahaluf-Recasens, Rodrigo; Porkhum, Olena; Weintraub, Andrés
The use of fire simulation tools has become a regular feature of support systems for fuel management decisions at landscape level. Considering the spatial nature of fire in the evaluation of risk and the definition of fire mitigation goals is an ongoing research topic in forest management planning. By combining a fire simulation tool, a growth and yield simulator and an optimization module, it is possible to minimize the negative impact of fire over time and maximize the yield of various ecosystem services. Specific requirements for a fire simulator adapted to support tactical forest planning include a level of accuracy, the possibility of exploring diverse fire scenarios, the computational capability to simulate multiple fires and the flexibility to generate different outputs or metrics depending on the specific requirements of the planning problem under study. The present article addresses the requirements of fire simulators for their inclusion on forest tactical planning. The Cell2Fire simulator is adapted for use with fuel models more commonly employed in Europe and the United States, and to simulate the generation and spread of crown fires. Already able to solve static fire mitigation problems in its original version, this new adaptation, known as Cell2Fire_SB, has been developed with the more ambitious goal of being integrated into a decision support system that simultaneously considers fire behavior forest dynamics and allocation of management actions in order to solve temporal dynamic tactical forest problems.
Open Access
A functional virgin olive oil enriched with olive oil and thyme phenolic compounds improves the expression of cholesterol efflux-related genes: A randomized, crossover, controlled trial
(MDPI, 2019) Farràs, Marta; Arranz, Sara; Carrión Bolorino, Silvia; Subirana Cachinero, Isaac; Muñoz-Aguayo, Daniel; Blanchart, Gemma; Kool, Marjon; Solà, Rosa; Motilva Casado, Mª José; Escolà Gil, Joan Carles; Rubió Piqué, Laura; Fernández Castillejo, Sara; Pedret, Anna; Estruch Riba, Ramon; Covas Planells, María Isabel; Fitó, Montserrat; Hernáez Camba, Álvaro; Castañer, Olga
The consumption of antioxidant-rich foods such as virgin olive oil (VOO) promotes high-density lipoprotein (HDL) anti-atherogenic capacities. Intake of functional VOOs (enriched with olive/thyme phenolic compounds (PCs)) also improves HDL functions, but the gene expression changes behind these benefits are not fully understood. Our aim was to determine whether these functional VOOs could enhance the expression of cholesterol efflux-related genes. In a randomized, double-blind, crossover, controlled trial, 22 hypercholesterolemic subjects ingested for three weeks 25 mL/day of: (1) a functional VOO enriched with olive oil PCs (500 mg/kg); (2) a functional VOO enriched with olive oil (250 mg/kg) and thyme PCs (250 mg/kg; FVOOT), and; (3) a natural VOO (olive oil PCs: 80 mg/kg, control intervention). We assessed whether these interventions improved the expression of cholesterol efflux-related genes in peripheral blood mononuclear cells by quantitative reverse-transcription polymerase chain reactions. The FVOOT intervention upregulated the expression of CYP27A1 (p = 0.041 and p = 0.053, versus baseline and the control intervention, respectively), CAV1 (p = 0.070, versus the control intervention), and LXRβ, RXRα, and PPARβ/δ (p = 0.005, p = 0.005, and p = 0.038, respectively, relative to the baseline). The consumption of a functional VOO enriched with olive oil and thyme PCs enhanced the expression of key cholesterol efflux regulators, such as CYP27A1 and nuclear receptor-related genes.
Open Access
A genome-wide screen for resilient responses in growing pigs
(BMC, 2022-07-04) Laghouaouta, Houda; Fraile Sauce, Lorenzo José; Suárez-Mesa, Rafael; Ros Freixedes, Roger; Estany Illa, Joan; Pena i Subirà, Ramona Natacha
Background There is a growing interest to decipher the genetic background of resilience and its possible improvement through selective breeding. The objective of the present study was to provide new insights into the genetic make-up of resilience in growing pigs by identifying genomic regions and candidate genes associated with resilience indicators. Commercial Duroc pigs were challenged with an attenuated Aujeszky vaccine at 12 weeks of age. Two resilience indicators were used: deviation from the expected body weight at 16 weeks of age given the growth curve of non-vaccinated pigs (∆BW) and the increase in acute-phase protein haptoglobin at four days post-vaccination (∆HP). Genome-wide association analyses were carried out on 445 pigs, using genotypes at 41,165 single nucleotide polymorphisms (SNPs) and single-marker and Bayesian multiple-marker regression approaches. Results Genomic regions on pig chromosomes 2, 8, 9, 11 (∆BW) and 8, 9, 13 (∆HP) were found to be associated with the resilience indicators and explained high proportions of their genetic variance. The genomic regions that were associated explained 27 and 5% of the genetic variance of ∆BW and ∆HP, respectively. These genomic regions harbour promising candidate genes that are involved in pathways related to immune response, response to stress, or signal transduction ( CD6 , PTGDR2 , IKZF1 , RNASEL and MYD88 ), and growth ( GRB10 and LCORL ). Conclusions Our study identified novel genomic regions that are associated with two resilience indicators (∆BW and ∆HP) in pigs. These associated genomic regions harbour potential candidate genes involved in immune response and growth pathways, which emphasise the strong relationship between resilience and immune response.
Open Access
A genomewide association study in divergently selected lines in rabbits reveals novel genomic regions associated with litter size traits
(Blackwell Verlag GmbH, 2019) Sosa‐Madrid, Bolívar Samuel; Santacreu, María Antonia; Blasco, Agustín; Fontanesi, Luca; Pena i Subirà, Ramona Natacha; Ibáñez-Escriche, N.
Uterine capacity (UC), defined as the total number of kits from unilaterally ovariectomized does at birth, has a high genetic correlation with litter size. The aim of our research was to identify genomic regions associated with litter size traits through a genomewide association study using rabbits from a divergent selection experiment for UC. A high‐density SNP array (200K) was used to genotype 181 does from a control population, high and low UC lines. Traits included total number born (TNB), number born alive (NBA), number born dead, ovulation rate (OR), implanted embryos (IE) and embryo, foetal and prenatal survivals at second parity. We implemented the Bayes B method and the associations were tested by Bayes factors and the percentage of genomic variance (GV) explained by windows. Different genomic regions associated with TNB, NBA, IE and OR were found. These regions explained 7.36%, 1.27%, 15.87% and 3.95% of GV, respectively. Two consecutive windows on chromosome 17 were associated with TNB, NBA and IE. This genomic region accounted for 6.32% of GV of TNB. In this region, we found the BMP4, PTDGR, PTGER2, STYX and CDKN3 candidate genes which presented functional annotations linked to some reproductive processes. Our findings suggest that a genomic region on chromosome 17 has an important effect on litter size traits. However, further analyses are needed to validate this region in other maternal rabbit lines.
Open Access
A genome‑wide association study for loin depth and muscle pH in pigs from intensely selected purebred lines
(BMC, 2023-06-15) Desire, Suzanne; Johnsson, Martin; Ros Freixedes, Roger; Chen, Ching-Yi; Holl, Justin; Herring, William O.; Gorjanc, Gregor; Mellanby, Richard J.; Hickey, John M.; Jungnickel, Melissa K.
Background Genome-wide association studies (GWAS) aim at identifying genomic regions involved in phenotype expression, but identifying causative variants is difficult. Pig Combined Annotation Dependent Depletion (pCADD) scores provide a measure of the predicted consequences of genetic variants. Incorporating pCADD into the GWAS pipeline may help their identification. Our objective was to identify genomic regions associated with loin depth and muscle pH, and identify regions of interest for fine-mapping and further experimental work. Genotypes for ~ 40,000 single nucleotide morphisms (SNPs) were used to perform GWAS for these two traits, using de-regressed breeding values (dEBV) for 329,964 pigs from four commercial lines. Imputed sequence data was used to identify SNPs in strong (≥ 0.80) linkage disequilibrium with lead GWAS SNPs with the highest pCADD scores. Results Fifteen distinct regions were associated with loin depth and one with loin pH at genome-wide significance. Regions on chromosomes 1, 2, 5, 7, and 16, explained between 0.06 and 3.55% of the additive genetic variance and were strongly associated with loin depth. Only a small part of the additive genetic variance in muscle pH was attributed to SNPs. The results of our pCADD analysis suggests that high-scoring pCADD variants are enriched for missense mutations. Two close but distinct regions on SSC1 were associated with loin depth, and pCADD identified the previously identified missense variant within the MC4R gene for one of the lines. For loin pH, pCADD identified a synonymous variant in the RNF25 gene (SSC15) as the most likely candidate for the muscle pH association. The missense mutation in the PRKAG3 gene known to affect glycogen content was not prioritised by pCADD for loin pH. Conclusions For loin depth, we identified several strong candidate regions for further statistical fine-mapping that are supported in the literature, and two novel regions. For loin muscle pH, we identified one previously identified associated region. We found mixed evidence for the utility of pCADD as an extension of heuristic fine-mapping. The next step is to perform more sophisticated fine-mapping and expression quantitative trait loci (eQTL) analysis, and then interrogate candidate variants in vitro by perturbation-CRISPR assays.
Open Access
A hydroclimatic model for the distribution of fire on Earth
(IOP Publishing Ltd, 2021-03-25) Boer, Matthias M.; Resco de Dios, Víctor; Stefaniak, Elisa Z.; Bradstock, Ross A.
The distribution of fire on Earth has been monitored from space for several decades, yet the geography of global fire regimes has proven difficult to reproduce from interactions of climate, vegetation, terrain, land use and other human activities by empirical and process-based fire models. Here, we propose a simple, yet robust, model for the global distribution of fire potential based on fundamental biophysical constraints controlling fire activity in all biomes. In our 'top-down' approach we ignored the dynamics of individual fires and focus on capturing hydroclimatic constraints on the production and (seasonal) desiccation of fuels to predict the potential mean annual fractional burned area at 0.25° spatial resolution, here estimated by the 0.99 quantile of the observed mean annual fractional burned area (${F}_{0.99}$) over the 1995-2016 period of the Global Fire Emissions Database (GFED4). We show that 80% of the global variation in ${F}_{0.99}$ can be explained from a combination of mean annual precipitation and potential evapotranspiration. The proposed hydroclimatic model reproduced observed 0.99 quantile fire activity levels equally well across all biomes and provided the first objective underpinning for the dichotomy of global fire regimes in two domains characterised by either fuel production limitations on fire or fuel dryness limitations on fire. A sharp transition between the two climate-fire domains was found to occur at a mean annual aridity index of 1.9 (1.94 ± 0.02). Our model provides a simple but comprehensive basis for predicting fire potential under current and future climates, as well as an overarching framework for estimating effects of human activity via ignition regimes and manipulation of vegetation.
Open Access
A LiDAR-Based System to Assess Poplar Biomass
(Springer-Verlag, 2016-06-21) Andújar, Dionisio; Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon; Sanz Cortiella, Ricardo; Rueda-Ayala, Victor; Fernandez Quintanilla, C.; Ribeiro, Angela; Dorado, José
This study evaluated the capabilities of a LiDAR-based system to characterize poplar trees for biomass production. The precision of the system was assessed by analyzing the relationship between the distance records and biophysical parameters. The terrestrial laser scanner (TLS) system consisted of a 2D time-of-flight LiDAR sensor, a gimbal to dynamically stabilize the sensor and a RTK-GPS to georeference its location and, subsequently, the sensor data. The sensor and its stabilizer were fixed facing downwards, on a metal frame designed for this purpose. Then, it was mounted on an all-terrain vehicle to perform 2D scans in planes perpendicular to the travel direction. Distances between the sensor and the surrounding objects had a high spatial resolution, providing high density 3D point clouds. Results on the reliability of the LiDAR system to estimate plant height showed a significant relationship between the sensor readings and actual poplar height and biomass data. In addition, tree biomass and tree volume were properly estimated in the point cloud. Regression analysis showed significant estimates of 0.79 and 0.89 for biomass and volume, respectively. These results reveal the potential of the LiDAR sensor to estimate both, plant height and plant biomass. This sensor's capability, added to its relative low cost, fast reaction, and the high number of readings per second consolidate the ideal system for estimating the productivity of biomass in energy crops. http://link.springer.com/article/10.1007%2Fs10343-016-0369-1
Open Access
A method to obtain orange crop geometry information using a mobile terrestrial laser scanner and 3D modeling
(MDPI, 2017) Colaço, André F.; Trevisan, Rodrigo G.; Molin, José P.; Rosell Polo, Joan Ramon; Escolà i Agustí, Alexandre
LiDAR (Light Detection and Ranging) technology has been used to obtain geometrical attributes of tree crops in small field plots, sometimes using manual steps in data processing. The objective of this study was to develop a method for estimating canopy volume and height based on a mobile terrestrial laser scanner suited for large commercial orange groves. A 2D LiDAR sensor and a GNSS (Global Navigation Satellite System) receiver were mounted on a vehicle for data acquisition. A georeferenced point cloud representing the laser beam impacts on the crop was created and later classified into transversal sections along the row or into individual trees. The convex-hull and the alpha-shape reconstruction algorithms were used to reproduce the shape of the tree crowns. Maps of canopy volume and height were generated for a 25 ha orange grove. The different options of data processing resulted in different values of canopy volume. The alpha-shape algorithm was considered a good option to represent individual trees whereas the convex-hull was better when representing transversal sections of the row. Nevertheless, the canopy volume and height maps produced by those two methods were similar. The proposed system is useful for site-specific management in orange groves.
Open Access
A Methodology to Quantify Resilience in Growing Pigs
(MDPI, 2021-10-15) Laghouaouta, Houda; Pena i Subirà, Ramona Natacha; Ros Freixedes, Roger; Reixach, Josep; Díaz, Marta; Estany Illa, Joan; Armengol Gelonch, Ramon; Bassols, Anna; Fraile Sauce, Lorenzo José
There is a growing concern about the genetic determinism of resilience and its possible implementation in breeding programs. The objective of our study was to elaborate novel resilience indicators in growing pigs based on the deviation from the expected growth curve and the increment of the acute-phase protein haptoglobin (HP) after applying a common vaccine. A total of 445 pigs were vaccinated with an attenuated Aujeszky vaccine at 12 weeks of age. Deviation from the expected body weight (DBW) given the growth curve of unvaccinated pigs at 28 days post-vaccination (DPV) and the increment of HP at 4 DPV (DHP) were suggested as resilience indicators. Challenged pigs that maintained their productivity and had a minor activation of HP were deemed resilient, whereas pigs that had low DBW values and a high activation of HP were deemed susceptible. Pigs were also classified based on DBW and DHP relative to the expected BW at 28 DPV and to the basal level of HP, respectively. The concordance was high between both methods, indicating that DBW and DHP are not sensitive to the animal's expected BW nor the basal level of HP. The heritability estimates were moderate for DBW (0.33) and low-to-moderate for DHP (0.16). Our study suggests DBW and DHP as novel resilience indicators in pigs. The suggested indicators capture different aspects of resilience, are easy to measure, and are genetically controlled. Thus, they may be improved through selective breeding. Further analyses are needed to validate our findings.
Open Access
A multi-proxy framework to detect insect defoliations in tree rings: a case study on pine processionary
(Frontiers Media SA, 2023) Camarero, J. Julio; Colangelo, Michele; Rita, Angelo; Hevia, Andrea; Pizarro, Manuel; Voltas Velasco, Jordi
Assessing and reconstructing the impacts of defoliation caused by insect herbivores on tree growth, carbon budget and water use, and differentiating these impacts from other stresses and disturbances such as droughts requires multi-proxy approaches. Here we present a methodological framework to pinpoint the impacts of pine processionary moth (Thaumetopoea pityocampa), a major winter-feeding defoliator, on tree cover (remote-sensing indices), radial growth and wood features (anatomy, density, lignin/carbohydrate ratio of cell walls, δ13C and δ18O of wood cellulose) of drought-prone pine (Pinus nigra) forests in north-eastern Spain. We compared host defoliated (D) and coexisting non-defoliated (ND) pines along with non-host oaks (Quercus faginea) following a strong insect outbreak occurring in 2016 at two climatically contrasting sites (cool-wet Huesca and warm-dry Teruel). Changes in tree-ring width and wood density were analyzed and their responses to climate variables (including a drought index) were compared between D and ND trees. The Normalized Difference Infrared Index showed reductions due to the outbreak of –47.3% and –55.6% in Huesca and Teruel, respectively. The D pines showed: a strong drop in growth (–96.3% on average), a reduction in tracheid lumen diameter (–35.0%) and lower lignin/carbohydrate ratios of tracheid cell-walls. Both pines and oaks showed synchronous growth reductions during dry years. In the wet Huesca site, lower wood δ13C values and a stronger coupling between δ13C and δ18O were observed in D as compared with ND pines. In the dry Teruel site, the minimum wood density of ND pines responded more negatively to spring drought than that of D pines. We argue that multi-proxy assessments that combine several variables have the potential to improve our ability to pinpoint and reconstruct insect outbreaks using tree-ring data.
Open Access
A new family of standardized and symmetric indices for measuring the intensity and importance of plant neighbour effects
(Wiley, 2016) Díaz Sierra, Rubén; Verwijmeren, Mart; Rietkerk, Max; Resco de Dios, Víctor; Baudena, Mara
1. Measurements of competition and facilitation between plants often rely upon intensity and importance indices that quantify the net effect of neighbours on the performance of a target plant. A systematic analysis of the mathematical behaviour of the indices is lacking and leads to structural pitfalls, e.g. statistical problems detected in importance indices. 2. We summarize and analyse themathematical properties that the indices should display. We reviewthe properties of the commonly used indices focusing on standardization and symmetry, which are necessary to avoid compromising data interpretation.We introduce a new family of indices ‘Neighbour-effect Indices’ that meet all the proposed properties. 3. Considering the commonly used indices, none of the importance indices are standardized, and onlyRII (Relative Interaction Index) displays all the required mathematical properties. The existing indices show two types of symmetries, namely, additive or commutative, which are currently confounded, potentially resulting in misleading interpretations. Our Neighbour-effect Indices encompass two intensity and two importance indices that are standardized and have different and defined symmetries. 4. Our new additive intensity index, NIntA, is the first of its kind, and it is generally more suitable for assessing competition and facilitation intensity than the widely used RII, which may underestimate facilitation. Our new standardized importance indices solve the main statistical problems that are known to affectCimp and Iimp. Intensity and importance with the same symmetry should be used within the same study. The Neighbour-effect Indices, sharing the same formulation, will allow for unbiased comparisons between intensity and importance, and between types of symmetry.

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