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La durabilité est une préoccupation grandissante des entreprises agroalimentaires et des consommateurs, menant à de nombreux signes spécifiques sur les aliments. Étudiant trois chaînes (purée de pomme et de mangue, vin), nous souhaitons expliquer les différences entre filières. Grâce à une méthodologie quantitative et qualitative, nous brossons un tableau des signes existants et montrons que les différences proviennent principalement du cadre institutionnel et de la gouvernance., Sustainability is an increasing concern for agrifood firms because of consumer requirements, leading to a wide range of related signals on the food. Considering three different food chains (apple and mango purees, wine), we aim to explain differences in sustainability signalling in food chains. Using a qualitative and a quantitative methodology, we provide an overview of existing signals and show that differences result primarily from governance and the institutional framework.

International audience

National audience; L’objectif de ce projet de recherche est d’évaluer l’impact d’une exposition alimentaire à un mélange de faibles doses de pesticides, lors de périodes de vulnérabilité périnatale, sur l’équilibre métabolique, la composition du microbiote intestinal et le système nerveux central. À partir d’un modèle animal (souris) mimant l’exposition des consommateurs, un cocktail de six pesticides (Captan, boscalide, chlorpyrifos, thiaclopride, thiophanate et ziram) utilisés dans le traitement des pommeraies en Occitanie sera testé par voie alimentaire.

International audience; Intragenesis is an important alternative to transgenesis to produce modified plants 27 containing native DNA only. A key point to develop such a strategy is the availability of 28 regulatory sequences controlling the expression of the gene of interest. With the aim of 29 finding apple gene promoters either inducible by the fire blight pathogen Erwinia amylovora 30 (Ea) or moderately constitutive, we focused on polyphenoloxidase genes (PPO). These genes 31 encode oxidative enzymes involved in many physiological processes and have been 32 previously shown to be up-regulated during the Ea infection process. We found ten PPO and 33 two PPO-like sequences in the apple genome and characterized the promoters of MdPPO16 34 (pPPO16) and MdKFDV02 PPO-like (pKFDV02) for their potential as Ea-inducible and low-35 constitutive regulatory sequences respectively. Expression levels of reporter genes fused to 36 these promoters and transiently or stably expressed in apple were quantified after various 37 treatments. Unlike pKFDV02 which displayed a variable activity, pPPO16 allowed a fast and 38 strong expression of transgenes in apple following Ea infection in a Type 3 Secretion System 39 dependent manner. Altogether our results indicate that pKFDV02 did not keep its promises as 40 a constitutive and weak promoter whereas pPPO16, the first Ea-inducible promoter cloned 41 from apple, can be a useful component of intragenic strategies to create fire blight resistant 42 apple genotypes.

European apple cultivation is based on a small number of elite cultivars. These cultivars are becoming increasingly vulnerable in the current climate change context because of their reduced diversity and narrow genetic base. Genetic resources may be a source of favorable alleles that are absent from elite material and thus the transfer of such alleles from genetic resources to elite material could help solve this problem. Genomic selection has been proposed to achieve this goal. This study aims to assess the accuracy of genomic prediction of elite material and genetic resources. We have used high density genotypic data (303239 SNPs) and populations of 847 to 1025 individuals. The characterization of the two populations using genotypic data showed a very weak differentiation (Fst = 0.004) between elite material and genetic resources. On the other hand, differences in minor allele frequencies (MAF) were observed throughout the genome of the two populations. Elite material has a weak family structure, while genetic resources show no structure. The GBLUP model and the cross-validation approach were applied to estimate the accuracy of predictions for seven phenotypic traits assessed in the two populations. The range of variation of all calculated accuracies ranged from 0.23 to 0.82. Accuracieswere higher for elite material than for genetic resources for three traits, with a mean difference ranging from 0.1 to 0.18, and higher for genetic resources than for elite material for two traits, with a mean difference ranging from 0.09 to 0.18. The two remaining traits obtained almost similar accuracies for the two populations. The low accuracies obtained for five of the seven traits indicates the need to improve accuracy by increasing the number of individuals.; La culture européenne de pomme est basée sur un petit nombre de variétés dites élites. Ces variétés deviennent de plus en plus vulnérables dans le contexte actuel de changement climatique car elles présentent peu de diversité et une base génétique étroite. Le transfert d’allèles à partir des ressources génétiques vers le matériel élite par la sélection génomique pourrait permettre de résoudre ce problème. Cette étude vise à évaluer la précision de la prédiction génomique du matériel élite et des ressources génétiques. Nous disposons de données génotypiques à haute densité (303239 SNPs) pour des individus représentant du matériel élite et des ressources génétiques en effectifs variant de 847 à 1025. La caractérisation des deux populations par les données génotypiques a montré une différentiation très faible (Fst = 0,004) entre le matériel élite et les ressources génétiques. Par contre des différences de fréquence d’allèles minoritaires ont été observées sur tout le long du génome entre les deux populations.Le matériel élite présente une faible structuration en familles à la différence des ressources génétiques qui ne montrent aucune structuration. Le modèle GBLUP et l'approche de validation croisée ont été appliqués pour estimer la précision de prédiction du modèle pour sept caractères phénotypiques évalués dans les deux populations. L’amplitude de variation de toutes les précisions calculées va de 0,23 à 0,82. Les précisions de prédiction étaient plus élevées pour le matériel élite que pour les ressources génétiques sur trois caractères, avec un écart variant entre 0,1 et 0,18, et plus élevées pour les ressources génétiques que pour le matériel élite pour deux caractères, avec un écart de 0,09 à 0,18. Les deux caractères restant ont obtenu des précisions presque similaires sur les deux populations. Les faibles précisions de prédiction obtenues sur cinq des sept caractères indiquent la nécessité d’améliorer la précision de prédiction en augmentant le nombre d’individus.

Apple chlorotic leaf spot virus (ACLSV), apple stem grooving virus (ASGV), and apple stem pitting virus (ASPV) cause significant losses to Brazilian (BR) apple production. Looking beyond these latent viruses, high-throughput sequencing (HTS) of three samples (Vacaria, Brazil) was performed on an Illumina HiSeq X Ten platform (USA), cv. Braeburn (BB), and a BGISEQ-500 platform (China), cvs. Royal Gala (RG) and Mishima (MI). Made available in DSpace on 2020-10-02T09:12:53Z (GMT). No. of bitstreams: 1 Arch-Virol-First-report-detection-of-three-bunya-like-viruses-First-look-27-05-20-b.pdf: 674383 bytes, checksum: 4c2bffb06fc4df836362c8d484a977d3 (MD5) Previous issue date: 2020

International audience

Modification of cell walls of apple, red beet and kiwifruit by heating in acid conditions: common and specific responses. 15th Cell wall meeting

Targeted genome engineering has emerged as an alternative to classical plant breeding and transgenic methods to improve crop plants. Among other methods (zinc finger nucleases or TAL effector nucleases) the CRISPR-Cas system proved to be the most effective, convenient and least expensive method. In this study, we optimized the conditions of application of this system on apple and explored its feasibility on pear. As a proof of concept, we chose to knock-out the Phytoene Desaturase (PDS) and Terminal Flower 1 (TFL1) genes. To improve the edition efficiency, two different single guide RNAs (gRNAs) were associated to the Cas9 nuclease for each target gene. These gRNAs were placed under the control of the U3 and U6 apple promoters. Characteristic albino phenotype was obtained for 85% of the apple transgenic lines targeted in MdPDS gene. Early flowering was observed in 93% of the apple transgenic lines targeted in MdTFL1.1 gene and 9% of the pear transgenic lines targeted in PcTFL1.1. Sequencing of the target zones in apple and pear CRISPR-PDS and CRISPR-TFL1.1 transgenic lines showed that the two gRNAs induced mutations but at variable frequencies. In most cases, Cas9 nuclease cut the DNA in the twenty targeted base pairs near the protospacer adjacent motif and insertions were more frequent than deletions or substitutions. The most frequent edition profile of PDS as well as TFL1.1 genes was chimeric biallelic. Analysis of a sample of potential off-target sequences of the CRISPR-TFL1.1 construct indicated the absence of edition in cases of three mismatches. In addition, transient transformation with the CRISPR-PDS construct produced two T-DNA free edited apple lines. Our overall results indicate that, despite the frequent occurrence of chimerism, the CRISPR-Cas 9 system is a powerful and precise method to induce targeted mutagenesis in the first generation of apple and pear transgenic lines.

International audience; Under natural growth conditions, plants experience various and repetitive biotic and abiotic stresses. Salicylic acid (SA) is a key phytohormone involved in the response to biotic challenges. Application of synthetic SA analogues can efficiently prime defense responses, and leads to improved pathogen resistance. Because SA analogues can result in long-term priming and memory, we identified genes for which expression was affected by the SA analogue and explored the role of DNA methylation in this memorization process. We show that treatments with an SA analogue can lead to long-term transcriptional memory of particular genes in Arabidopsis. We found that subsequent challenging of such plants with a bacterial elicitor reverted this transcriptional memory, bringing their expression back to the original pre-treatment level. We also made very similar observations in apple (Malus domestica), suggesting that this expression pattern is highly conserved in plants. Finally, we found a potential role for DNA methylation in the observed transcriptional memory behavior. We show that plants defective in DNA methylation pathways displayed a different memory behavior. Our work improves our understanding of the role of transcriptional memory in priming, and has important implication concerning the application of SA analogues in agricultural settings.

The rising concern of European consumers for pesticides residues left on fruit and of some far distant countries in Asia and Americas for quarantine organisms has turned compliance with SPS requirements into one of the main challenges of the French apple industry. Using transaction cost and cognitive governance theories, we investigate how differences in property rights structures, inter-firm arrangements, and mechanisms of firm governance may impact the modalities of SPS risk management. Our case study of two leading groups of the French fresh apple industry with different property rights structures (cooperative vs. private) and different marketing strategies (customers with more or less stringent SPS requirements) highlight the role of cognitive governance mechanisms (knowledge sharing) in the management of SPS risks. This paved the way for integrating governance structures, cognitive resources, and transaction attributes into a single model.

National audience; The aim of this paper is to illustrate the concept of path dependence through the case of a cold treatment technique used in the international apple trade during sea transit to prevent the introduction or dissemination of quarantine organisms in importing countries. We show that this technique is now systematically required and functions as a “de facto” standard, despite the existence of potentially less costly, and equally effective, alternative treatment methods. Drawing on the institutional literature on path dependence, we show that the negotiation costs that an exporting country would have to bear in order to have its trading partners accept a more efficient alternative method can be so high that it becomes preferable to continue using the current technique despite its higher adoption cost.; Dans cet article, les auteurs illustrent le concept de dépendance de sentier avec le cas d’un dispositif de traitement au froid utilisé pendant le transit maritime dans le commerce international des pommes pour empêcher l’introduction ou la dissémination d’organismes de quarantaine dans les pays importateurs. Ils montrent que ce dispositif est aujourd’hui systématiquement requis et fonctionne comme une norme de facto malgré l’existence de modalités de traitement alternatives potentiellement moins onéreuses et tout aussi efficaces. Conformément au cadre théorique mobilisé, les auteurs indiquent les coûts de négociation qu’un pays exportateur devrait supporter pour faire accepter à ses partenaires commerciaux un dispositif alternatif plus efficient, peuvent s’avérer si élevés qu’il devient préférable de continuer à utiliser le dispositif en usage malgré son coût d’adoption supérieur.

Le projet Sustain'Apple s'est intéressé aux régulations phytosanitaires dans le commerce international et aux dispositifs institutionnels pour se mettre en conformité avec ces régulations. Les régulations phytosanitaires sont surtout le fait de nouveaux pays importateurs de pommes françaises (notamment en Asie et en Amérique du Sud) qui cherchent ainsi à éviter d'importer et de disséminer des organismes de quarantaine (en particulier les insectes) et à limiter les effets économiques des organismes non régulés qui pourraient être introduits. L'analyse s'est focalisée sur les dispositifs publics/privés qui élaborent, négocient et gèrent les protocoles phytosanitaires permettant d'accéder aux marchés convoités. Une comparaison avec le Chili et l'Italie a permis d'identifier les forces et faiblesses du système français. L'intérêt pour une telle comparaison vient d'une double interrogation : comment expliquer le contraste important de positionnement de marché entre la France et l'Italie d'une part et le Chili d'autre part, le Chili étant de loin le plus implanté sur les marchés à contraintes phytosanitaires; comment expliquer les problèmes d'efficacité institutionnelle dans la préparation et la négociation des protocoles phytosanitaires (insuffisante circulation de l'information et coopération avec les services de la protection des végétaux), révélés par quelques responsables professionnels. L'analyse comparée des dispositifs institutionnels a été conduite après avoir effectué un positionnement de marché des trois pays et identifié pour chacun d'eux, les problèmes de quarantaine rencontrés et les contraintes phytosanitaires imposées par les principaux pays clients.

International audience; Apple fruit growth is the result of several factors: inherent demand (relative sink strength) of the fruit (defined by the demands for cell division and expansion growth, etc.), carbon assimilation by the source leaves (source strength), and the resulting allocation to the organ in question. It is thus a complex process involving source-sink interactions. In the present study, we designed an experimental system in which parts of fruit-bearing branches of two apple cultivars ("Fuji" and "Ariane") were isolated from the rest of the tree by girdling and then subjected to specific pruning and fruit removal treatments to create a wide range of global (branch-level) source-sink ratios. We monitored not only fruit kinetics but also photosynthesis as a response to light in leaves of the three different shoot types (i.e., the rosette, the bourse, and the vegetative shoots) to 1) study the impact of source-sink distance on carbon partitioning between fruits within the same branch and 2) to investigate the impact of source/sink ratio on fruit growth and leaf photosynthetic activity. Our results indicate 1) no significant differences among lateral fruits belonging to different ranks, and this independent of source availability; 2) that a modification of the source/sink ratio seems to be compensated by an alteration of the photosynthetic rate of leaves, with stronger and weaker values obtained for lower and higher ratios, respectively. Moreover, our results seem to suggest that two growing sinks together will upregulate photosynthesis rate more strongly than one growing sink does on its own, and this with the same leaf area per fruit. These results are discussed, and some hypotheses are put forward to explain them.

The Sustain'Apple project deals with phytosanitary regulations in international trade and the institutional devices to comply with those regulations. Phytosanitary regulations are issued by new destination countries (mostly in Asia and North and South America) to avoid importing and disseminating quarantine organisms (in particular pests) and limit the economic effects of regulated non-quarantine organisms. Our report focuses on public and private devices which formulate, negotiate and implement the phytosanitary protocols that exporting countries must comply with, to get access to targeted markets. By comparing France with Italy and Chile, we have been able to identify strengths and weaknesses of the French system. The interest for such a comparison arouses from the two following questions : first how can we explain the contrasted market positioning between France and Italy on one hand and Chile on the other hand, Chile having by far the largest market share in destinations with phytosanitary constraints; second, how can we explain low institutional efficacy in preparing and negotiating phytosanitary protocols as revealed by professional leaders who regret lack of information from and weak cooperation with plant protection services. The institutional devices comparison has been conducted after having positioned the markets of the three countries and identified, for each of them, issues of quarantine pests and phytosanitary constraints imposed by main customer countries.

Background Systems biology aims to analyse regulation mechanisms into the cell. By mapping interactions observed in different situations, differential network analysis has shown its power to reveal specific cellular responses or specific dysfunctional regulations. In this work, we propose to explore on a large scale the role of natural anti-sense transcription on gene regulation mechanisms, and we focus our study on apple (Malus domestica) in the context of fruit ripening in cold storage. Results We present a differential functional analysis of the sense and anti-sense transcriptomic data that reveals functional terms linked to the ripening process. To develop our differential network analysis, we introduce our inference method of an Extended Core Network; this method is inspired by C3NET, but extends the notion of significant interactions. By comparing two extended core networks, one inferred with sense data and the other one inferred with sense and anti-sense data, our differential analysis is first performed on a local view and reveals AS-impacted genes, genes that have important interactions impacted by anti-sense transcription. The motifs surrounding AS-impacted genes gather transcripts with functions mostly consistent with the biological context of the data used and the method allows us to identify new actors involved in ripening and cold acclimation pathways and to decipher their interactions. Then from a more global view, we compute minimal sub-networks that connect the AS-impacted genes using Steiner trees. Those Steiner trees allow us to study the rewiring of the AS-impacted genes in the network with anti-sense actors. Conclusion Anti-sense transcription is usually ignored in transcriptomic studies. The large-scale differential analysis of apple data that we propose reveals that anti-sense regulation may have an important impact in several cellular stress response mechanisms. Our data mining process enables to highlight specific interactions that deserve further experimental investigations. Electronic supplementary material The online version of this article (10.1186/s12918-018-0613-7) contains supplementary material, which is available to authorized users.

Nowadays, complying with technical, sanitary and phytosanitary (SPS) regulations and standards is becoming more and more demanding due to their proliferation and increasing complexity. Consequently, increasing requirements in plant health protection and food safety can lead to a loss of competitiveness in countries that are major exporters of fresh products, causing a redistribution of the market shares in certain sectors. Exporters complying with regulatory standards benefit from better market access and avoid boarder rejection or product downgrading but incur additional costs due to additional procedures and paperwork. This is the case for French apples producers which are losing competitiveness compared to the Chilean ones on foreign markets. This situation can be partially explained by the difficulties of French exporters to comply with international SPS requirements. The aim of this article is first to make a compilation of phytosanitary requirements facing French and Chilean exporters of fresh apples, then to propose a score (hereafter phytosanitary score) which allows to assess the degree of complexity of these SPS requirements. This score is interesting as it synthesizes qualitative information in a metric which can be easily used in quantitative analysis. The results show that even if France and Chile are rather close in terms of SPS requirements, Chilean apples exporters are more capable to comply with foreign SPS requisites than the French ones., Bio-based and Applied Economics, Vol 7 No 1 (2018)

International audience; Agricultural supply chains are providers and receivers of ecosystem services. Providers when supplying food, non-food products and services; and receivers as they benefit from natural resources (Le Roux et al., 2008). Agriculture and its supply chains must be considered as social-ecological systems due to the participation of different actors that interact within natural, economic, institutional and social dimensions (Moraine et al., 2015). Partners within the supply chains coordinate to organize exchanges while managing the natural resources and adapting to changes and uncertainties, whether linked to natural or to economic factors. This study focuses the analysis on two fruit-based food supply chains: apples and mangoes, particularly at the interface between agricultural raw materials and processing. Supply chains of fruits are especially complex. At the production stage, climate, i.e. sunlight, temperature, humidity among other agronomical factors, are source of variability and heterogeneity of the raw material. Beside the influence of climate on the quality attributes of fruit, climate also affects the apparition of plant diseases, which on one hand, have direct and harmful effects on fruit quality, and on the other, trigger the use of phytosanitary substances to control pests with the consequently emergence of chemical hazards due to residues in fruits. This complexity makes more difficult for growers and processors to control the food quality which is increasingly relevant and demanding. Quality has evolved towards a more comprehensive concept that beyond the organoleptic and nutritional attributes, involve the respect for sanitary, social and ecological considerations. Firms, i.e. growers, processors, traders and distributors of the supply chains, have the responsibility to satisfy consumer, to protect human health and to protect natural resources. Firms have also the challenge of ensuring their own position in a highly competitive and uncertain environment. To do so, they implement strategies to control quality and to protect assets involved in transactions with partners that can also be competitors (Menard, 2013:130). This study asks the question: How do firms manage the variability and the heterogeneity of fruits within the supply chains? To answer this question, our framework is the New Institutional Economics. We resort to the institutional analysis applied to the agricultural sector by Menard (2013, 2014, 2017), that allows a better understanding of the multilayer institutions in place to regulate the social-ecosystems. Using a qualitative method of analysis, we gathered primary information from 54 firms with a main focus on France for apples and mangoes (La Reunion), we also explored other European, Asian and Latin-American countries to have a wider scope of analysis and comparison. We uncover the main problems concerning quality of products, and the strategies of coordination adopted by firms within the supply chains.

Microstructure evolution of foods during cooking is difficult to assess because of the need of sensitive non destructive technique. To study such phenomena in apple, we undertook MRI, quantitative NMR and mechanical experiments at key temperatures of the cooking process (45, 50, 53, 60 and 70°C). MRI measurements were performed at 9.4 T with a 30mm diameter 1H volume coil. We acquired 10 SE images at different TE (4.5 to 200ms), with a single echo per acquisition for preventing refocusing errors (TR=3000ms, voxel vol. 1mm3 isotropic, duration 32min) to map T2 assuming a monoexponential decrease. NMR CPMG acquisitions, 90°x-[ -180°y- -(echo)]n, were also carried out ( =500μs and n=128). Data were fitted using non-negative least squares algorithm fed with a decomposition basis made of 200 T2 logarithmically-spaced from 1ms to 1000ms. In parallel, we performed puncture tests with a 2mm diameter flat end needle descending at 1mm/min until the strain reached 70%. Both T2 maps and quantitative NMR show a dramatic change in T2 values between raw and cooked parenchyma at a transition temperature of around 50°C. This change can be interpreted by the filling of pores after thermal permeabilization of the cell membranes. The effective T2 obtained by imaging is sensitive to internal magnetic field gradients, due to susceptibility differences (Van As et al., 1997). Then, this T2 is shorter than the CPMG’s bulk T2 in the porous material (before 50°C) and it dramatically increases when the pores are filled. The resistance to a mechanical stress also displays a sharp decrease, for a slightly higher temperature of 53°C. This temperature shift supports the hypothesis of a complex thermal denaturation of the plasmalemma, first releasing vacuolar water before being structurally affected (Bourles et al., 2009). This work emphasizes the interest of multiscale relaxation studies for studying thermal denaturation of food products. CPMG allows resolving multiple T2 compartments in the whole sample whereas imaging is sensitive to heterogeneities.

Fruits have been traditionally classified into two categories based on their capacity to produce and respond to ethylene during ripening. Fruits whose ripening is associated to a peak of ethylene production and a respiration burst are referred to as climacteric, while those that are not are referred to as non-climacteric. However, an increasing body of literature supports an important role for ethylene in the ripening of both climacteric and non-climacteric fruits. Genome and transcriptomic data have become available across a variety of fruits and we leverage these data to compare the structure and transcriptional regulation of the ethylene receptors and related proteins. Through the analysis of four economically important fruits, two climacteric (tomato and apple), and two non-climacteric (grape and citrus), this review compares the structure and transcriptional regulation of the ethylene receptors and related proteins in both types of fruit, establishing a basis for the annotation of ethylene-related genes. This analysis reveals two interesting differences between climacteric and non-climacteric fruit: i) a higher number of ETR genes are found in climacteric fruits, and ii) non-climacteric fruits are characterized by an earlier ETR expression peak relative to sugar accumulation

Description of the subject. The article deals with the use of near-infrared spectroscopy (NIR) on fresh apples to determine the phenolic compounds and dry matter content in peel and flesh powders.Objectives. The aim is the rapid and non-destructive determination of these nutritional parameters.Method. Two hundred twenty-nine fruits from 20 varieties were analyzed with NIR spectroscopy and reference methods.Results. Great variability of total phenolic compounds (TPC) in peel and flesh powders was observed among varieties. The dry matter (DM) content also differed greatly between peel and flesh. Calibration and validation models showed high coefficients of determination for the TPC content, which were slightly higher for the peel than for the flesh (R² val = 0.91 and 0.84 respectively). For the DM content, high coefficients of determination and ratios of prediction to deviation (RPDs) were also observed (R² val = 0.94, RPD = 4.8 and R² val = 0.94, RPD = 4.9 for the peel and flesh respectively). Conclusions. Calibration and validation models allow quantitative predictions to be made for TPC and DM content. They confirm the potential of NIRS for predicting the polyphenol content and highlight its potential for determining the DM content, a parameter often neglected in research into apple quality., Utilisation de la spectroscopie NIR sur les pommes pour déterminer les teneurs en polyphénols et en matière sèche de la pelure et de la chair des fruitsDescription du sujet. L’article traite de l’utilisation de la spectroscopie proche infrarouge (NIR) sur les pommes pour déterminer les teneurs en polyphénols totaux et en matière sèche des poudres de pelure et de chair du fruit.Objectifs. Le but est de pouvoir déterminer de façon rapide et non destructive ces composés nutritionnels.Méthode. Deux-cent-vingt-neuf fruits provenant de 20 variétés ont été analysés par spectroscopie NIR et avec les méthodes de référence.Résultats. Une grande variabilité du contenu en polyphénols a été observée au sein des variétés. La teneur en matière sèche est également très variable et diffère entre la pelure et la chair. Les modèles de calibration et validation ont montré de hauts coefficients de détermination pour la teneur en polyphénols totaux, légèrement plus élevée pour la pelure que pour la chair (R² val = 0,91 et 0,84 pour la pelure et la chair respectivement). Pour la teneur en matière sèche, de hauts coefficients de détermination et de hauts rapports RPD ont également été observés (R² val = 0,94, RPD = 4,8 et R² val = 0,94, RPD = 4,9 pour la pelure et la chair respectivement).Conclusions. Les modèles développés permettent des prédictions quantitatives des teneurs en polyphénols totaux et en matière sèche. Ces résultats confirment le potentiel de la spectroscopie NIR pour prédire la teneur en polyphénols totaux et met en évidence son potentiel pour déterminer la matière sèche, un paramètre souvent négligé dans la recherche sur la qualité des pommes.

International audience; Regulated deficit irrigation, which is a common practice to cope with water scarcity, can impact plant-aphid interactions, and possibly lead to a reduction in the use of pesticides. To test the possible effect of water restriction on the apple tree-rosy apple aphid (Malus domestica-Dysaphis plantaginea) system, we performed a factorial experiment with two levels of water supply and two genotypes on artificially infested trees. Plant growth and aphid abundance were characterised during the entire infestation period at two scales of analysis: the apical shoot scale and the tree scale, and additional measures were performed to evaluate plant water status. Aphid abundance increased with plant vegetative growth at both scales of analysis, which is consistent with the Plant Vigor Hypothesis (i.e. with the fact that most of the phloem feeders prefer fast growing plants). At the tree scale, aphid abundance was lower on trees that underwent water restriction, but at the shoot scale, aphid abundance responded differently to water restriction depending on the tree genotype. Water restriction modified the relationship between aphid abundance and growth, thus indicating that host suitability for aphids was affected by different plant variables susceptible to water stress, among which growth. The different response patterns at the two scales of analysis highlight the importance of scale choice in the study of plant-insect interactions.