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Comparative analysis of crop phenotypes to assess cropping system diversification potential by introducing improved accessions of Thinopyrum intermedium in fields
No full textInternational audienc
Fruit production without synthetic chemical inputs in the Pilat, challenges and prospects for change
No full textAgricultural specialisation or diversity in local areas: issues, benefits and limitations, conditions for transitionCarrefour de l'innovation agronomique on Thursday 9 November 2023 at ENSAT in ToulouseInternational audienceA dynamic production of high-quality apples has developed within the Pilat Natural Regional Park thanks to favourable pedoclimatic conditions, the ingenuity of local farmers, but also synthetic chemical input use. We conducted a holistic inquiry to identify the sociotechnical lock-ins that explain the difficulty in producing fruit without synthetic chemical inputs. This was done by investigating a diverse range of actors involved in Pilat fruit production. We characterized a sociotechnical system structured around an agricultural cooperative marketing apples to mass-market retail, as well as niche dynamics. These elements, and their interconnections, have helped us to identify possible sociotechnical transition pathways towards the establishment of fruit production with a decreased dependence on synthetic chemical inputs
Identifying keys of success for relay intercropping of service crop in a winter cereal
No full textInternational audienceIntroducing service crops into rotations may help to reduce dependency to inputs. Service provision largely depends on biomass production (Vrignon-Brenas et al., 2016b). Relay intercropping into winter cereal may favor conditions for service crop emergence, without impairing cereal yield (Gardarin et al., 2022). Nonetheless, this technique is complex and service crop establishment could fail, preventing its large adoption by farmers. Soil and climate conditions can explain variability of success (Vrignon-Brenas et al., 2016a). It is also the result of competition for resources in a complex system formed by winter cereal, service crop and weeds. This study takes profit from 15 years of experiment on such technique to determine what are the key factors to succeed in establishing the service crop for the provision of expected services
Characterization of antimicrobial multilayer film based on ethylcellulose-pectin incorporated with nanoemulsions of trans-cinnamaldehyde essential oil
No full textInternational audienceIn this study, polymer solution casting was utilized to fabricate a multilayer film with ethylcellulose (EC) as the outer layers and trans-cinnamaldehyde-loaded pectin as the inner layer. A significant increase in whiteness and UV–visible light blocking capability and a remarkable decrease in total color difference and yellowness of the films were seen via increasing the thickness of EC outer layers. Scanning electronic microscopy observation showed that the inner and outer layers had a smooth and uniform surfaces with clear boundary. The thicker film has better stretchability and strength, but is less flexible than thinner film. Glass transition temperature did not change remarkably with increasing thickness of EC outer layers, but thermal stability was slightly improved. FTIR-ATR spectra revealed the formation of hydrogen bonds between the two adjacent layers. The multilayer films exhibited excellent antimicrobial efficacy against Gram-positive and Gram-negative foodborne pathogens. The results suggested that this multilayer film has potential applications in active food packaging
Does transport stress have any effect on carcass quality of Nellore cattle ( Bos taurus indicus ) in Brazil? - A case study
No full textInternational audienceWith the increasing concomitant demands for Brazilian beef and in particular high-quality beef, there is a need for observational studies of the effects of pre- and post-slaughter practices on beef carcass traits. We hypothesized in our case study that pre-slaughter transport of bovines over significant distances would induce stress in animals, and that this would reduce carcass quality because of higher pH resulting from long-distance transportation. To test this hypothesis, 30,230 Nellore carcasses from a private slaughterhouse were evaluated 24 h postmortem. Analysis showed correlations between animal maturity, ultimate pH, distance, and carcass weight. More precisely, there was a slight positive correlation between ultimate pH and weight (but not with transportation distance) and a slight positive correlation between maturity and weight. A linear regression model (R2 = 0.016) failed to show distance having a significant effect on ultimate pH (P = 0.63), while carcass weight significantly affected ultimate pH (P < 0.001) with a low coefficient of 0.0003. Maturity negatively affected ultimate pH also (P < 0.001) but with also a small effect (−0.0008). Results (from 95% confidence intervals of variance of the random effects and of the random errors) showed that the variability within farms was higher than between farms. The linear mixed model showed that maturity had a significant effect on carcass weight value (P < 0.001) with a large coefficient of 2.90. The R2 of the linear mixed model was 46.03%. In conclusion, while weight and maturity both affect ultimate pH, long distances did not significantly impact ultimate pH and therefore the beef quality from Nellore cattle. This could be because of low stress during transport, as well as the physical characteristics of the Nellore breed that favor greater resistance to tropical climatic conditions
GENERATION OF SYSTEMIC CHIMERAS WITH RABBIT INDUCED PLURIPOTENT STEM CELLS REPROGRAMMED WITH KLF2, ERAS AND PRMT6
No full textInternational audienceEmbryo-derived and induced pluripotent stem cells (ESCs and iPSCs, respectively) exist in two different states, designated naive and primed. Naïve and primed states differ by the signalling pathways, transcription factors and epigenetic regulators that hold the cells in one of either state. In rabbits, ESCs and iPSCs only exist in the primed state of pluripotency.We developed a strategy that led to identify factors capable of reprogramming rabbit iPSCs to a naïve-like, embryo-colonization competent state. We conducted an unbiased screening of a cDNA library encoding a panel of 36 factors, including transcription factors, epigenetic regulators and signalling molecules associated with naïve-state pluripotency in rodents and primates. All the factors were randomly introduced into rabbit primed iPSCs by means of lentivector infection, followed by clonogenic growth in a FGF2/KOSR-deprived culture media containing LIF, activin A, PKC and WNT inhibitors. The three transgenes most frequently detected were PRMT6 that encodes an arginine methyl transferase, ERAS that encodes a GTPase, and KLF2 that encodes Krüppel-like factor 2. To investigate the transgene action, KLF2, ERAS and PRMT6 were overexpressed, either separately, in pairwise combinations, or all three together, in rabbit iPSC cells, either constitutively or with induction. KLF2 was necessary and sufficient to sustain self-renewal in a FGF2/KOSR-deprived culture regimen. The addition of both ERAS and PRMT6 led to the appearance of a subset of cells expressing the naïve state-specific marker CD75 at a high level. These CD75high cell population underwent epigenetic reconfiguration typical of naïve-state pluripotency including reactivation of the 2nd X-chromosome. Remarkably, the CD75high cells gained the ability to produce chimeric embryos and fetuses, showing a high contribution in all major organs. Our results describe for the first systemic chimeras in the rabbit species, similar to the chimeras produced in mice with ES cells
Les étangs piscicoles : puits ou sources de carbone ?: Rôle des producteurs primaires et des pratiques de gestion
No full textNational audienceLes étangs jouent un rôle majeur dans le cycle global du carbone. Ils ont à la fois la capacité à être des puits de carbone à travers la sédimentation mais sont, en même temps, des émetteurs importants de gaz à effet de serre (CO2 et CH4 principalement). Le carbone atmosphérique est capté par les producteurs primaires (algues et plantes aquatiques) lors de la photosynthèse. A l’inverse, les milieux aquatiques contribuent à plus de la moitié des émissions de méthane d’origine anthropique. Dans un contexte de changement climatique, le rôle des étangs piscicoles, comme potentiels puits ou sources de carbone, et l’influence des pratiques piscicoles appliquées, sont peu connus.Pour cela, nous avons suivi 20 étangs piscicoles de la Dombes (Ain, France) pendant une saison de production en 2022 et 5 d’entre eux pendant leur année d’assec en 2023. Nous avons mesuré à la fois la sédimentation et le carbone organique stocké dans les sédiments. Mais aussi les différents types d’émissions (diffusion et ébullition) de CO2, CH4 et N2O au cours de trois saisons (printemps, été et automne) dans le but d’estimer leur bilan carbone (stockage – émissions).Nos résultats montrent une forte variabilité pour les différents paramètres mesurés. En moyenne, les étangs apparaissent comme étant des puits de carbone (4,16 tonnes de CO2 équivalent par ha sur 6 mois ; 6 étangs comme sources et 14 comme puits). Le stockage est en moyenne de 12,24 tonnes et les émissions de 8,08 tonnes. L’ébullition de méthane représente le flux majoritaire. Pendant l’année d’assec, les étangs suivis sont des sources de carbone pour l’atmosphère avec une moyenne de 23,89 tonnes de CO2eq/ha/6 mois émises. Sur un cycle de production global (6 ans), les étangs piscicoles semblent être des sources de carbone. Ces bilans sont majoritairement expliqués par les producteurs primaires, sous l’influence des pratiques de gestion comme la fertilisation ou l’assec.Ces données confirment que les étangs piscicoles peuvent à la fois être des puits ou des sources de carbone. Néanmoins, en favorisant la présence de plantes aquatiques et d’un bon niveau de production primaire, les pratiques de gestion apparaissent comme des leviers intéressants pour faire de ces étangs des puits de carbone. Ces agroécosystèmes pourraient donc jouer un rôle important au sein des paysages agricoles dans un contexte de changement climatique
Diversity and structure of macrophyte communities in two different fish pond systems: Dombes (France) and Midden-Limburg (Belgium)
No full textInternational audienceAgricultural intensification and the expansion of farmland in recent decades have contributed to a drastic decline in biodiversity. Different types of production systems, like land sharing or land sparing strategies – try to reconcile production and biodiversity conservation. Among all these agricultural landscapes, there are many in Europe with ponds (also called "pondscapes") for fish production. These fish ponds ecosystems can contain remarkable biodiversity, including rich communities of macrophytes with several rare or protected species. However, intensification of fish farming practices increasingly results in pond ecosystem deterioration and the loss of this biodiversity. The diversity and structure of communities in relation to different fish production strategies remains little studied.Our work aims to fill this knowledge gap by investigating how fish stock management affects macrophyte community characteristics at different spatial scales. For this purpose, we used data about macrophytes communities collected in 2022 in multiple fish ponds, in two important European pondscapes (17 from Dombes in France and 21 from Midden-Limburg in Belgium) with different fish management strategies. All ponds in the Dombes region are used for extensive fish farming (land sharing principle), whereas pond management in Midden-Limburg is more variable and includes ponds for fish farming (high fish density) and ponds without fish for purposes of biodiversity conservation (land sparing principle).Our results show a significant negative effect of higher fish density on the species diversity of macrophytes. Fish density also has an effect on community’s composition. Nestedness predominates over turnover between the different types of fish stock management. Fishless ponds help to maintain species that are not present in ponds for fish production. Despite their different communities, the two regions show similar gamma diversity.Our results confirm the negative effect of intensive production of benthic fish on macrophytes community composition and diversity. Neither system seems to be a better alternative for macrophyte conservation. By going beyond this simple binary choice, we can say that an "ideal fish pondscape” for maintaining both productivity and biodiversity conservation should be a mixture of both strategies, to diversify conditions and habitats. Inside this landscape, fish-free managed ponds also seem essential for maintaining additional macrophytes species, not found in ponds for fish production
Travail agricole et transition agroécologique : quelles interactions, quels impacts et quelles conséquences pour l'agronomie et les agronomes ? [éditorial]
No full textCe numéro d’Agronomie, environnement & sociétés rend compte à la fois des travaux du débat agronomique de l’AFA de mars 2023 et de la 12ème édition des Entretiens agronomiques Olivier de Serres. Ces travaux ont porté sur l’analyse des enjeux du travail agricole pour les agronomes, sur le panorama des travaux en cours portant sur les différentes dimensions du travail, et sur une réflexion prospective pour les activités des agronomes de la recherche, du développement et de la formation. L’ensemble de ces réflexions et travaux prennent en compte les impacts et les conséquences des évolutions du travail en agriculture dans le contexte de la transition agroécologique
91. Effect of the follicular puncture method on in vitro maturation of porcine oocytes
No full textInternational audienceProtocols for in vitro maturation of porcine oocytes usually involve collecting ovaries from an abattoir, transporting them to a laboratory ina phosphate-buffered saline solution at a fixed temperature and finally puncturing them. The oocytes retrieved are then sorted andmatured. This study aimed to confirm that the in vitro maturation rate could be improved by puncturing the follicles directly on site(i.e., on the slaughter line) and then transporting their contents to the laboratory in a suitable medium at 37°C. To assess oocyte qualityafter maturation, we compared effects of abattoir puncture to those of laboratory puncture on the nuclear and cytoplasmic maturationrates of porcine oocytes after in vitro maturation. Oocytes were stained with Hoechst 33342 for the nuclear stage and FITC-PNA to assesscortical granule (GC) distribution and observed by confocal microscopy. The nuclear stages identified were the germinal vesicle, immatureoocyte and mature oocyte. The oocytes were classified into three types according to the GC distribution pattern: immature, incomplete orfully mature. Follicular puncture performed at the abattoir and in the laboratory showed similar rates of nuclear maturation (90.7 ± 4.1%and 84.7 ± 6.2% respectively). However, the abattoir puncture showed a better cytoplasmic maturation rate than the laboratory puncture(45.3 ± 12.6% vs 19.0 ± 14.6%, P < 0.01). In addition, the abattoir puncture yielded higher-quality structures before maturation. It was alsoeasier to maintain oocytes at 37°C than it was to maintain ovaries at room temperature