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Spatial and temporal diversity of service plant management strategies across vineyards in the south of France. Analysis through the Coverage Index
No full textInternational audienceHighlights:• Spontaneous service plants strategies present a high spatial and temporal diversity.• Strategies can be measured by calculating the Coverage Index (CI) for each vineyard.• Higher CI was linked to quality labels, organic crop protection and low target yields.• No link was found between CI and water and soil resources in vineyards.• Target services by winegrowers are consistent with the CI and period coverage.Abstract: 'Service plants' include spontaneous vegetation or sown species of cover crops associated with perennial crops in the rows or inter-rows with a high potential to provide ecosystem functions and services. In vineyards, service plants target specific services depending on the management strategy implemented by the winegrower, including the plant species, the surface covered, the plant growth control and destruction date. Understanding the management strategies linked to their associated target services at the regional scale is necessary to better help winegrowers, advisers and policy makers regarding an adapted use of service plants. To do this, we conducted a survey in 2016 among 334 winegrowers in Languedoc-Roussillon region in France, enquiring about their service plant management practices during the season 2014-2015. Given the diversity of the strategies of service plant management, we proposed a typology analyzing their spatial and temporal dimensions. Further, we present a Coverage Index (CI), which combines both temporal and spatial dimensions of the service plant management strategies. We conducted a multiple components analysis and clustering to create a vineyard typology and applied linear models to find correlations between the CI and specific vineyard characteristics. Three quarters of interviewed winegrowers sowed or maintained service plants in their vineyards; 41 % used a winter service plant strategy; 8.4 % a semi-permanent and 27.3 % a permanent service plant strategy. The preferred surface coverage strategy was full surface during grapevine dormancy and its reduction to half of the inter-rows after grapevine budburst. However, the diversity of surface coverage strategies during the grapevine vegetative period was remarkable. Lower water resources and specific soil characteristics were not linked to the service plant management strategies. Higher CI was associated with vineyards presenting quality labels (PDO and Organic), independent wine-making and lower target yields, showing that the added value of producing high quality wine plays an important role when implementing service plants in vineyards. Overall, our study showed: i) the popularity of spontaneous service plant strategies; ii) the spatial and temporal diversity of service plant management strategies and iii) the utility of the CI to study the implementation of service plants and to understand the motivations and constraints of their use
Effects of the donor factors and freezing protocols on the bovine embryonic lipid profile
No full textInternational audienceEmbryo lipid profile is affected by in vitro culture conditions, that lead to an increase in lipids. Efforts have been made to optimize embryo lipid composition as it is associated with their quality. The objective of this study was to evaluate whether the diet supplementation of donor cows (n-3 or n-6 PUFA), or the slow freezing protocols (ethylene glycol sucrose EG-S vs. glycerol trehalose GLY-TRE), or the physiological stage of the donor (nulliparous heifers vs. primiparous lactating cows) may impact the bovine embryo lipid profile. Lipid extracts of 97 embryos were individually analysed by liquid chromatography-high resolution mass spectrometry, highlighting 246 lipids including 85% being overabundant in cow embryos compared to heifer embryos. Among 105 differential lipids, 72 were overabundant after EG-S protocol, including a single glycerophosphate PA(32:1) representing 27.3% of the significantly modulated lipids, suggesting that it is degraded when GLY-TRE is used. No lipids were different according to the n-3 or n-6 supplementation of the donor cows. In conclusion, the embryonic lipid profile was mainly affected by the physiological stage of the donors and the slow freezing protocols. The overabundance of lipids in lactating cow embryos and the resulting lower quality of these embryos is consistent with the lower pregnancy rate observed in cows compared to heifers. Unlike GLY-TRE protocol, EG-S freezing allowed to preserve glycerophospholipids potentially improving the slow freezing of in vitro-produced embryos. Further studies are required to modulate embryo quality and freezability by modulating the lipidome and integrating all stages of embryonic production
An unbiased screening for transcription factors and chromatin remodelers that reset pluripotent stem cells to naïve-like pluripotency
No full textInternational audiencePluripotent Stem Cells (PSCs) include embryo-derived and induced pluripotent stem cells (ESCs and iPSCs, respectively). Mouse PSCs can be stabilized in vitro in two pluripotent states : the naive state and the primed state. Naïve and primed states differ by the signalling pathways, transcription factors and epigenetic regulators that hold the cells in one of either state. Only the naïve mESCs have the ability to colonize the epiblast of the blastocyst and generate chimeras; PSCs in the primed state cannot. In rabbits and other non-rodent species, cells derived from early epiblast or generated by somatic cell reprogramming can only be maintained in the primed state of pluripotency. This study aims to identify genes capable of reprogramming conventional primed rabbit iPSCs (rbiPSCs) to the naïve state of pluripotency
Water quality issues and agriculture: An international review of innovative policy schemes
No full textInternational audienceCurrent agri-environmental policies are facing challenges to protect the environment, including in delivering water quality improvements. These difficulties are mainly due to payment restrictions and field or farm scale limitations in existing policy schemes. Innovative approaches have emerged in the last decades to overcome these constraints, such as market-based, landscape-scale and food-chain approaches. In order to understand the potential of these approaches to deal with water quality issues, we have analysed the design features of 62 innovative agri-environmental schemes. We grouped them into nine types of instruments that could provide benefits on water quality and we identified three main drivers for change that are: rewarding environmental outcomes, encouraging collaboration between rural stakeholders and certifying agri-environmental practices within the agri-food chain. The diversity of the schemes reviewed emphasizes the importance of the local context, which strongly conditions the effectiveness of instruments. Furthermore, mixing several schemes seems promising to encompass multiple governance levels involving both public and private actors
Apoptosis, G1 Phase Stall, and Premature Differentiation Account for Low Chimeric Competence of Human and Rhesus Monkey Naive Pluripotent Stem Cells
No full textInternational audienceAfter reprogramming to naive pluripotency, human pluripotent stem cells (PSCs) still exhibit very low ability to make interspecies chimeras. Whether this is because they are inherently devoid of the attributes of chimeric competency or because naive PSCs cannot colonize embryos from distant species remains to be elucidated. Here, we have used different types of mouse, human, and rhesus monkey naive PSCs and analyzed their ability to colonize rabbit and cynomolgus monkey embryos. Mouse embryonic stem cells (ESCs) remained mitotically active and efficiently colonized host embryos. In contrast, primate naive PSCs colonized host embryos with much lower efficiency. Unlike mouse ESCs, they slowed DNA replication after dissociation and, after injection into host embryos, they stalled in the G1 phase and differentiated prematurely, regardless of host species. We conclude that human and non-human primate naive PSCs do not efficiently make chimeras because they are inherently unfit to remain mitotically active during colonizatio
Deciphering the pluripotency continuum in rabbit pre-implantation embryos
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Gene expression patterns associated with dental replacement in the rabbit, a new model for the mammalian dental replacement mechanisms
No full textInternational audienceBackgroundUnlike many vertebrates with continuous dental replacement, mammals have a maximum of two dental generations. Due to the absence of dental replacement in the laboratory mouse, the mechanisms of the mammalian tooth replacement system are poorly known. In this study, we use the European rabbit as a model for mammalian tooth development and replacement.ResultsWe provide data on some key regulators of tooth development. We detected the presence of SOX2 in both the replacement dental lamina and the rudimentary successional dental lamina of unreplaced molars, indicating that SOX2 may not be sufficient to initiate and maintain tooth replacement. We showed that Shh does not seem to be directly involved in tooth replacement. The transient presence of the rudimentary successional dental lamina in the molar allowed us to identify genes that could be essential for the initiation or the maintenance of tooth replacement. Hence, the locations of Sostdc1, RUNX2, and LEF1 vary between the deciduous premolar, the replacement premolar, and the molar, indicating possible roles in tooth replacement.ConclusionAccording to our observations, initiation and the maintenance of tooth replacement correlate with the presence of LEF1+ cells and the absence of both mesenchymal RUNX2 and epithelial Sostdc1+ cells
Brazilian Consumers’ Attitudes towards So-Called “Cell-Based Meat”
No full textInternational audienceThe main goal of this online survey was to investigate the attitudes of Brazilians towards “cell-based meat”, which has become the subject of great scientific and media enthusiasm. The answers of 4471 respondents concluded that 46.6% of them thought “cell-based meat” was promising and acceptable. More than 66% would be willing to try this novel product compared to 23% who expressed reluctance to do so. Nearly 40% of the total respondents did not want to eat “cell-based meat” regularly at all, whereas 29%, 43.2%, and 39.9% were willing to eat it regularly in restaurants, at home, and/or in ready-made meals, respectively. However, the majority of respondents (71%) were keen to pay much less for “cell-based meat” than conventionally produced meat (or even nothing at all), compared to 24.3% who were willing to pay the same price as conventional meat, whereas only 4.8% were willing to pay more. Approximately 51% of them considered that “cell-based meat” should not be called “meat” for marketing purposes. Job, monthly income, age, and gender were major factors impacting consumer acceptance. Meat professionals and consumers with higher incomes were less willing to eat “cell-based meat” regularly. Women (especially younger women) were the most concerned about the ethical and environmental issues related to meat production and were the most convinced that reducing meat consumption could be a good solution to the meat industry’s problems. Respondents who did not accept “cell-based meat” and did not eat meat substitutes had a negative attitude to this novel food (they considered it absurd and/or disgusting) and did not believe that “cell-based meat” should be called “meat” for marketing purposes. In contrast, the people who thought that “cell-based meat” could be called “meat” perceived it in a rather positive way. These results are important for consumers of meat and meat substitutes and for companies aiming to enter the potential future Brazilian market of “cell-based meat”
Process-based analysis of Thinopyrum intermedium phenological development highlights the importance of dual induction for reproductive growth and agronomic performance
No full textInternational audienceIntermediate wheatgrass (Thinopyrum intermedium (Host) Barkworth & D.R. Dewey) is being developed for use as a new perennial grain crop through breeding and agronomic research. However, progress has been hampered by lack of understanding of environmental requirements for flowering and grain production. Therefore, we developed a phenology model for IWG adapted from the STICS soil-crop model. The model was compliant with experimental results (relative root mean square error = 0.03). The optimal vernalizing temperature was between 4 and 5 • C, optimal daylength between 13 and 14h, while daylength below 11h slowed reproductive development. Vernalization requirement was found to be a constraining inductive process. Including a photoperiod limitation to the model with temperature improved its ability to predict induction at various latitudes. Therefore, timing and duration of vegetative vs. reproductive growth may differ between environments and change reproductive tiller elongation earliness, weed competitiveness, management timing, and stress conditions during phases critical to grain yield. Accurate phenology models will enable optimal field management and inform future breeding strategies. However, plasticity may lead to divergent ideotypes under various agroecosystems
