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Global perspectives and transdisciplinary opportunities for locust and grasshopper pest management and research
No full textInternational audienceLocusts and other migratory grasshoppers are transboundary pests. Monitoring and control, therefore, involve a complex system made up of social, ecological, and technological factors. Researchers and those involved in active management are calling for more integration between these siloed but often interrelated sectors. In this paper, we bring together 38 coauthors from six continents and 34 unique organizations, representing much of the social -ecological -technological system (SETS) related to grasshopper and locust management and research around the globe, to introduce current topics of interest and review recent advancements. Together, the paper explores the relationships, strengths, and weaknesses of the organizations responsible for the management of major locust -affected regions. The authors cover topics spanning humanities, social science, and the history of locust biological research and offer insights and approaches for the future of collaborative sustainable locust management. These perspectives will help support sustainable locust management, which still faces immense challenges such as fluctuations in funding, focus, isolated agendas, trust, communication, transparency, pesticide use, and environmental and human health standards. Arizona State University launched the Global Locust Initiative (GLI) in 2018 as a response to some of these challenges. The GLI welcomes individuals with interests in locusts and grasshoppers, transboundary pests, integrated pest management, landscape -level processes, food security, and/or cross-sectoral initiatives
The ISO 14001 standard's effect on agrifood small and medium‐sized enterprises' performance: Literature review and empirical evidence
No full textInternational audienceA significant part of the literature postulates the importance of economic factors and, in particular, market pressure as the main motivation for the adoption of environmental management systems, such as ISO 14001 (International Organization for Standardization). Most of these studies are based on questionnaire surveys assessing the perceptions or opinions of company managers. Few studies have investigated the relationship between the adoption of the standard and economic and financial performance using objective accounting data. This study aimed to test the link between ISO 14001 adoption and economic and financial performance using accounting data from 374 agrifood small‐ and medium‐sized enterprises (SMEs) in Spain during the period 2013 to 2015. The results showed that ISO 14001 contributes to improved commercial and marketing performance through a positive effect on turnover in domestic markets and especially in export markets. However, no positive relationship could be found between ISO14001 and company results or profits. Therefore, ISO 14001 can be considered more as a means of entering and developing sales, particularly in export markets, than a tool to enhance financial profits
A Novel Multi-camera Fusion Approach at Plant Scale: From 2D to 3D
No full textInternational audienceNon-invasive crop phenotyping is essential for crop modeling, which relies on image processing techniques. This research presents a plant-scale vision system that can acquire multispectral plant data in agricultural fields. This paper proposes a sensory fusion method that uses three cameras, Two multispectral and a RGB depth camera. The sensory fusion method applies pattern recognition and statistical optimization to produce a single multispectral 3D image that combines thermal and near-infrared (NIR) images from crops. A multi-camera sensory fusion method incorporates five multispectral bands: three from the visible range and two from the non-visible range, namely NIR and mid-infrared. The object recognition method examines about 7000 features in each image and runs only once during calibration. The outcome of the sensory fusion process is a homographic transformation model that integrates multispectral and RGB data into a coherent 3D representation. This approach can handle occlusions, allowing an accurate extraction of crop features. The result is a 3D point cloud that contains thermal and NIR multispectral data that were initially obtained separately in 2D
Can agroforestry protect crops from cavitation / hydraulic failure ?: Proposition to link a Crop-Growth Model and an Hydraulic Faillure Model
No full textInternational audienceAgroforestry systems (AFS) are pushed as an adaptation solution of agrosystems against climate change (CC) (IPCC, 2022). Given the time constraint of tree growth, modelization and simulation are necessary. In this regard, the Hi-sAFe model (Dupraz et al. , 2019) is one solution available. This model has been successfully used to assess the biophysical impact of CC on AFS (Reyes et al., 2021). However, by design, the Hi-sAFe model is not able to fully represent the physiology of plants (both crop and trees) under hydric stress and hydraulic failure situation. The SUREAU model (Cochard et al., 2021) is a mechanistic model focused on the hydraulic architecture of plants and the water resistance and water capacitances of their organs. Thanks to the SUREAU model, it is possible to represent , at plant scale, the hydraulic failure that can happen in situation of hydric stress. Here we propose a linkage of the Hi-sAFe model to the SUREAU to investigate the possibility to model hydraulic failure at plant level in agroforestry plot
Identifier, nommer et classer les types de vigne dans l’Antiquité : approche croisée des textes et des restes archéobotaniques
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Recharge and dynamics of the Tamanrasset alluvial aquifer (Algerian Sahara)
No full textInternational audiencePopulation growth and agricultural intensification are ever more demanding in water resources, and threaten their quality and quantity, especially in semi-arid and arid areas. The Sahara desert is typical of these multiple constraints and rapid changes making sustainable management of water resources a major issue. The wide regional aquifers have nearly fossil water. In contrast, alluvial aquifers associated with small wadis are recharged nearly each year by the rare floods. In the case of Wadi Tamanrasset, in southern Algeria, the alluvial aquifer is exploited intensively because of its accessibility and its good chemical quality. The physical conditions commanding flow and recharge of groundwater, and especially the transfer from surface to groundwater, were studied by combining hydrodynamics and isotopic tracers (18O, 2H). Monthly monitoring of groundwater level in around thirty wells was complemented by automatic recorders with hourly time steps since March 2016 in three wells, along a 600 m transect perpendicular to the wadi bed. The slow response of the water table is visible only two months after the first flood; its maximum rise was 1 m in 2016. Isotopic analyses of rainwater on a daily time scale, of the wadi water on a 1 h time scale during runoff and of groundwater (two complete campaigns in the dry and wet seasons and a specific monitoring of the transect every month) have provided additional information on surface-groundwater transfer
Grape development revisited through the single-berry metabolomic clock paradigm
No full textInternational audienceAlthough the ripening process of grapevine berries is well-documented at the vineyard level, pinpointing distinct developmental stages remains challenging. The asynchronous development of berries results in dynamic biases and metabolic chimerism. It is thus crucial to consider individual berries separately and resynchronize their internal clock for deciphering physiological changes throughout development. Given the importance of grape composition in wine quality, we aimed at measuring developmental changes in the metabolome of Syrah single berries from anthesis to over-ripening, without a priori preconceived. Non-targeted UHPLC-HRMS analyses of single berries yielded 9,335 compounds with specific mass and retention time. This dataset was submitted to an analysis workflow, combining classification and dimension reduction tools, to reveal the dynamics of metabolite composition. The outcomes of this workflow highlight an innovative redefinition of developmental stages, through the clustering of metabolites into 11 specific kinetic patterns. More precisely, the usual double sigmoidal growth pattern could be split into more transient stages characterized by the accumulation of specific metabolites. For instance, we identified a cluster of metabolites annunciative of the onset of ripening at the end of the herbaceous plateau which witnesses transient lipidic changes. We also found a cluster composed of stilbenes that accumulate during berry shriveling, following sugar loading. This non-targeted approach enables a more precise and unbiased characterization of grapevine berry development through the metabolomic clock paradigm, paving the way for a better assessment of berry physiological stage in genetic studies and ultimately for varietal selection and adaptation to climate change
Timber Tracking of Jacaranda copaia from the Amazon Forest Using DNA Fingerprinting
No full textInternational audienceWe investigated the utility of nuclear and cytoplasmic single nucleotide polymorphism (SNP) markers for timber tracking of the intensively logged and commercialized Amazonian tree Jacaranda copaia. Eight hundred and thirty-two trees were sampled (cambium or leaves) from 38 sampling sites in Bolivia, Brazil, French Guiana, and Peru. A total of 128 SNP markers (113 nuclear, 11 chloroplastic, and 4 mitochondrial) were used for genotyping the samples. Bayesian cluster analyses were carried out to group individuals into homogeneous genetic groups for tests to self-assign groups of individuals or individuals to their population of origin. Cluster analysis based on all the SNP markers detected seven main genetic groups. Genetic differentiation was high among populations (0.484) and among genetic groups (0.415), and populations showed a strong isolation-by-distance pattern. Self-assignment testing of the groups of individuals for all loci was able to determine the population origin of all the samples (accuracy = 100%). Self-assignment tests of individuals were able to assign the origin of 94.5%–100% of individuals (accuracy: 91.7%–100%). Our results show that the use of the 128 SNP markers is suitable to correctly determine the origin of J. copaia timber, and they should be considered a useful tool for customs and local and international police
Tick-borne Apicomplexa in wildlife and ticks of French Guiana
No full textInternational audienceTick-borne Apicomplexa encompass a group of parasites responsible for significant medical and veterinary diseases, including babesiosis, theileriosis, and hepatozoonosis. In this study, we investigated the presence and diversity of tick-borne Apicomplexa in wildlife and ticks inhabiting the Amazon rainforests of French Guiana. To this end, we conducted molecular screening and typing using 18S rRNA sequences on a collection of 1161 specimens belonging to 71 species, including 44 species of wild mammals, five species of passerines, and 22 species of ticks. We characterized eight genovariants of Babesia, Theileria, Hemolivia, and Hepatozoon parasites, some matching known species, while others suggested potential novel species. These parasites were detected in wild mammals, including opossums, sloths, armadillos, porcupines, margays, greater grisons, and ticks, but not in passerines. Finally, similarities with surveys conducted in Brazil highlight the specific sylvatic transmission cycles of South American tick-borne Apicomplexa.Les Apicomplexes transmis par les tiques englobent un groupe de parasites responsables de maladies médicales et vétérinaires importantes, notamment la babésiose, la theilériose et l’hépatozoonose. Dans cette étude, nous avons étudié la présence et la diversité des Apicomplexes transmis par les tiques dans la faune sauvage et les tiques habitant les forêts tropicales amazoniennes de Guyane française. À cette fin, nous avons effectué un criblage moléculaire et un typage à l’aide de séquences d’ARNr 18S sur une collection de 1 161 spécimens appartenant à 71 espèces, dont 44 espèces de mammifères sauvages, cinq espèces de passereaux et 22 espèces de tiques. Nous avons caractérisé huit génovariants des parasites Babesia, Theileria, Hemolivia et Hepatozoon, certains correspondant à des espèces connues tandis que d’autres suggéraient de nouvelles espèces potentielles. Ces parasites ont été détectés chez des mammifères sauvages, dont des opossums, des paresseux, des tatous, des porcs-épics, des margays, des grisons et des tiques, mais pas chez des passereaux. Enfin, des similitudes avec des enquêtes menées au Brésil mettent en évidence les cycles de transmission sylvatiques spécifiques des Apicomplexa transmis par les tiques d’Amérique du Sud