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Apple trees in agroforestry – Investigating the plasticity of vegetative and reproductive traits
No full textInternational audienceAgroforestry is promoted as a way to improve the sustainability of horticultural systems through plant diversification and also to mitigate climate change through carbon sequestration. It could also alleviate excessive light and temperature in high-radiation regions of the world. However, little is known about the long-term shade adaptation of the temperate fruit tree in agroforestry systems. A study was developed to investigate apple growing under walnut trees in two shade conditions compared to a full light condition. Our aim was to quantify the plasticity of traits and the covariations between traits in these three light conditions using a multiscale approach considering different scales from whole tree to annual shoot and inflorescence. Shade did not affect the height of the apple trees, while it reduced the diameter of the trunk and branches. On the other hand, the totalnumber of growing shoots was reduced in shade, and flowering and fruiting were fewer and more irregular than in full light. Strikingly, at the whole tree scale, covariations between vegetative traits (trunk cross-sectional area versus mean branch cross-sectional area) and between vegetative and reproductive traits (trunk cross-sectional area versus total number of inflorescences) were not altered by shade. However, at the shoot scale, return-bloom was significantly reduced by shade, whereas at the inflorescence scale shade did not affect leaf number or leafarea. We propose a shade adaptation syndrome that includes not only shade intensity but also shade dynamics during the growing season and over consecutive years
Floral transition A genetic regulatory network controlling floral transition in apple
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MusaDeepMosaic: Development of a machine learning Genomic Mosaic classifier tool.
No full textInternational audienceMachine learning and deep learning offer promising prospects for the analysis of biological data and the efficiency of image analysis, particularly in the field of genomic characterization to provides through automation, reproducibility, and accuracy of biological image and genomic analysis. Genomic diversity can be represented by SNP markers encoded in image form (bitmap), allowing an operational computational representation of genetic complexity. Bitmap images can be processed by machine learning algorithms [1] or other automated tools, enabling faster and more accurate analysis of genomic data.Our recent research has focused on the analysis of genetic variation within different banana populations using single nucleotide polymorphisms (SNPs) markers. This approach enabled us to define SNPs diversity groups linked to ancestral genomes [2, 3, 4]. The genome of cultivated varieties were then visualized as colored mosaics, which provided a unique visual representation of the genetic complexity of the banana genome ancestry. All cultivated varieties display a composite chromosomic structure with a complex mosaic of segments from different wild species and sub-species that was curated into groups [6]. However, the precise definition of these groups and their attribution to specific ancestors requires expert manual work. The present study describes MusaDeepMosaic intends to facilitate the classification based on pattern recognition. The methodology is using the machine learning model that combine an image-based visualization module transformation of mosaic plot and a convolutional neural network-based classification module adapted for our case. The first step was to define reference groups, which allowed us to segment the data into training classes. However, to improve the accuracy of our model, we needed to significantly increase our data set. Due to the different sequencing technology, we normalized our data. This was done using a data augmentation method adapted to our dataset, which allowed us to expand our data corpus without compromising quality. The ResNet-50 model, a 50-layer deep convolutional neural network introduced in 2015 for image recognition, was utilized in this study. Optimized for accurate performance and fast processing times, ResNet-50 will be integrated into an automated system capable of characterizing newly genotyped individuals, analyzing the new genetic data, and automatically assigning individuals to the appropriate diversity groups.The initial results of our data augmentation and normalization efforts, based on clustering, are encouraging. MusaDeepMosaic will be trained on 1,483 simulated and 317 experimental plots representing the groups of cultivars which is the train dataset. The test dataset comprised 200 plots and the validation dataset contain 178 plots. MusaDeepMosaic achieved a higher level of accuracy (0,97 to 1). This type of classifier will complement VcfHunter tools [2, 3, 4, 5] to analyze and characterize the diversity of the cultivars present in the International Musa Transit Center (Alliance Bioversity CIAT, CGIAR)
L'économie d'énergie en agriculture indoor : étude des effets de modifications de la photopériode sur les paramètres agronomiques et la physiologie pré et post récolte des laitues
No full textFaced with today's challenges, agricultural production methods have diversified, notably with the development of controlled-environment agriculture, also known as indoor farming. This type of agriculture is highly efficient in terms of water use, but consumes large amounts of energy due to the need for artificial light. The aim of this thesis was to study the impact of photoperiod modifications to reduce lighting time and thus save energy. The effects of these modifications were studied on the agronomic parameters and physiology of pre- and post-harvest lettuces. This work is a collaboration between Avignon University and Futura Gaïa Technologies, an indoor farming company that designs and markets "turnkey" vertical farms containing horizontal axis rotary crop systems. The first task was to characterize the impact of rotation, which disrupts the perception of gravity. This disruption results in a reduction in stomatal conductance, photosystem II efficiency and net photosynthesis, but has no impact on marketable lettuce yield after 30 days of cultivation. Secondly, photoperiod modifications showed that lengthening the dark period led to a reduction in net photosynthesis as a result of disruption of the circadian rhythm of stomatal opening. The analyses thus enabled us to define the periods when the plants used light most efficiently, and to propose two new photoperiod modalities offering 12.5% and 25% savings in light hours and therefore energy. The fresh mass yield of lettuces under the '12.5%' modality is similar to that of control lettuces, thanks to better hydration, although dry mass is lower than that of control lettuces. The fresh and dry mass yields of lettuces under the '25%' modality are half those of control lettuces. Measurements of net photosynthesis as a function of time have shown that dry mass yield losses are a consequence of the phase shift between photoperiod and the circadian rhythm of stomatal opening, which alters the rhythm and reduces stomatal opening. Complementary experiments have led to the hypothesis that photoreceptors sensitive to red light (660 nm) and involved in the rhythm and intensity of stomatal opening could be used to improve light efficiency in controlled-environment agriculture. This thesis thus supports the idea of considering chronoculture, which should be combined with other energy-saving methods, to improve the sustainability of indoor farming.Face aux enjeux actuels, les méthodes de production agricole se sont diversifiées, notamment avec le développement de l'agriculture en environnement contrôlé, appelée aussi agriculture indoor. Cette agriculture a une bonne efficience de l'eau mais consomme une grande quantité d'énergie à cause de l'apport de lumière artificielle. L'objectif de cette thèse a été d'étudier l'impact de modifications de photopériode permettant de réduire le temps d'éclairement et donc d'économiser de l'énergie. Les effets de ces modifications ont été étudiés sur les paramètres agronomiques et la physiologie des laitues en pré et post-récolte. Ce travail est une collaboration entre Avignon Université et Futura Gaïa Technologies, une entreprise d'agriculture indoor qui conçoit et commercialise des fermes verticales « clés en main » contenant des systèmes de cultures rotatifs à axe horizontal. Le premier travail a été de caractériser l'impact de la rotation, qui perturbe la perception de la gravité. Cette perturbation se traduit par une diminution de la conductance stomatique, de l'efficience du photosystème II et de la photosynthèse nette, mais n'impacte pas le rendement commercialisable des laitues après 30 jours de culture. Ensuite, les modifications de photopériode ont montré que l'allongement de la période d'obscurité induit une diminution de la photosynthèse nette suite à la perturbation du rythme circadien de l'ouverture stomatique. Les analyses ont ainsi permis de définir les périodes où les plantes utilisaient la lumière de la manière la plus efficiente, ce qui a permis de proposer deux nouvelles modalités de photopériode permettant 12.5% et 25% d'économie des heures d'éclairement et donc d'énergie. Le rendement en masse fraîche des laitues sous la modalité '12.5%' est similaire à celle des laitues témoins grâce à une meilleure hydratation, bien que la masse sèche soit plus faible que celle des laitues témoins. Les rendements en masse fraîche et sèche des laitues sous la modalité ‘25%' sont deux fois plus faibles que ceux des laitues témoins. Les mesures de photosynthèse nette en fonction du temps ont montré que les pertes de rendement en masse sèche sont une conséquence du déphasage entre la photopériode et le rythme circadien de l'ouverture stomatique, ce qui altère le rythme et diminue l'ouverture stomatique. Des expérimentations complémentaires ont permis d'émettre l'hypothèse que les photorécepteurs sensibles à la lumière rouge (660 nm) et impliqués dans le rythme et l'intensité de l'ouverture stomatique pourraient être utilisés pour améliorer l'efficience de la lumière en agriculture en environnement contrôlé. Cette thèse soutient ainsi l'idée de prendre en considération la chronoculture, qui devra être associée aux autres méthodes d'économie d'énergie, pour améliorer la durabilité de l'agriculture indoor
La transition agroécologique : Quel accompagnement dans les Réserves de biosphère françaises ?
No full texthttps://sfecologie.org/regard/r121-mai-2024-c-herve-et-al-mab-et-transition-agroecologique
Health crisis and wine exports: How should the missions of export managers be adapted?
No full textInternational audienceThe global health crisis that unfolded at the beginning of 2020 has significantly disrupted international business operations. The majority of prior studies have focused on the impacts of crisis contexts at a strategic level, primarily within corporate leadership. This chapter presents the findings of a study carried out among a sample of French executives, managers and export sales professionals. The aim is to understand the effects of the Covid-19 crisis on their respective occupations. This study will enable us to assess how a crisis can facilitate the reflection and adaptation of practices to evolving environmental conditions. Historically, France is among the world's three leading wine exporters, alongside Italy and Spain. Despite the diversity of roles, wine export management operates at two main levels. The first mission involves the acquisition of new clients and the second mission revolves around retaining existing customers
"They will be like a person with a disease": A qualitative investigation of variation in contraceptive side-effect experiences in Central Oromia, Ethiopia
No full textInternational audienceContraceptive side-effects are consistently given as the main reason why women are dissatisfied with contraception or choose not to use it. However, why some women suffer more from side-effects remains unknown. Through inductive analysis of in-depth interviews and focus groups discussions with 40 contraceptive users and 3 key informants in Central Oromia, Ethiopia, we explored women’s rationales for variation in side-effect experiences. The data first reveal the wide diversity in type and severity of side-effect experiences reported by users of contraception. Second, we found that women’s rationales for why some individuals suffer more side-effects from contraception invoke economic and physical hardship (food insecurity and heavy workloads), as well as interindividual differences in biology (one’s blood must ‘fit’ with contraception). Finally, the analysis revealed the tension many women face in trying to negotiate the trade-off between the consequences of these side-effects with those of an unwanted pregnancy. The results show the value of using a biosocial approach, which centres women’s voices and experiences, for informing the measurement of contraceptive side-effects within population health surveys and clinical trials and for gaining a greater understanding of how an individual’s social, biological, and cultural contexts drive variation in when and why different side-effects manifest
Collective strategies and positioning: The case of the Loire Volcanique Initiative
No full textInternational audienceSeveral collective initiatives are emerging in the French wine industry to highlight common characteristics and consolidate often limited resource. This chapter illustrates the steps, strengths and challenges in constructing a collective strategy through the presentation of a research action approach, conducted between 2016 and 2018, with small vineyards in the Massif Central region of France. These small vineyards are characterized by unique identities, different and sometimes conflicting expectations, and distinct project management approaches. Using a methodological research-accompaniment approach, the chapter demonstrates how the process of establishing a positioning for these vineyards reconciled the specificities of individual structures with the requirements of a constructed collective strategy. The study of these vineyards provided the necessary foundation for the marketing initiatives initiated in 2019: the establishment of an association and a “brand”, Loire Volcanique . Finally, the chapter outlines the current developments and prospects arising from the new collective positioning of these vineyards
Wine management and marketing 2: Responses of the industry to crises and new expectations [Introduction]
No full textInternational audienceThis second volume of Wine Management and Marketing, following the first volume published in 2021, proposes to present new studies on issues in the sector, on the competitiveness of companies, and on organizations in a competitive but highly regulated market context. Therefore, it approaches the wine industry in different dimensions, with plural approaches, authors specializing in different disciplines of the social sciences, economics and management, and different angles and objects of study, in order to try to shed light on its complexity. Thus, the subjects of the various chapters proposed concern organizations or companies, often specialized in the production or trade of wine; they may also concern the sector or industry as a whole. In all cases, the authors, who are researchers strongly committed to this sector, were then able to consider many industrial specificities that give the industry a special place within the agricultural and agri-food industries. The bias here is once again to multiply approaches beyond the frontiers of marketing sensu stricto, sometimes management sciences or economics, since they shed light on wine markets and the impact of certain actions on the general economy and the competitiveness of the sector [...
Understanding levers and barriers of the emergence and persistence of emerging rural circular biocluster initiatives: Case of Occitanie region in the south of France
No full textInternational audienceContexteThe circular bioeconomy presents an opportunity to transform our relationship with resources and create a more sustainable future. Rural circular bioclusters play a crucial role in this transition by bringing together local actors to valorise waste and promote sustainable practices. Understanding the factors that influence their success is essential for ensuring their long-term viability and impact.•A biocluster is a type of sustainability-oriented cluster, with a geographically close group of interconnected companies and associated organisations in the field of the bioeconomy (Ayrapetyan and Hermans, 2020). •The viability of an emerging regional biocluster is its ability to maintain, innovate, co-create and share value while respecting the environmental limits and taking into account the social issues of the area in which it is located. MethodologyTo gain insights into the factors influencing rural circular bioclusters, we employed a mixed-methods approach. We first conducted a comprehensive literature review to establish a theoretical framework. Then, we carried out semi-directive interviews with key actors involved in bioclusters in the Occitanie region. These interviews allowed us to gather in-depth information about the experiences, challenges, and opportunities faced by these initiatives.ResultsOur analysis revealed that the success of rural circular bioclusters is influenced by a complex interplay of factors. These factors can be categorized as either levers or barriers, depending on their impact on the biocluster's development. Levers, such as strong leadership, clear common rules, and access to funding, can facilitate biocluster growth and success. On the other hand, barriers, such as excessive control, rigid rules, and dependence on external funding, can hinder biocluster development and sustainability.Discussion and ConclusionIn conclusion, understanding the factors that influence rural circular bioclusters is essential for their sustainable development and long-term impact. By identifying and addressing the barriers, stakeholders can create an enabling environment for bioclusters to flourish. Bioclusters, in turn, can contribute to regional economic growth, environmental protection, and social well-being, fostering a more sustainable future for rural communities.To address these challenges, we developed the Emerging Rural Circular Bioclusters Viability Canvas. This multi-criteria tool empowers regional leaders to assess their initiatives through a comprehensive business model evaluation