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How efficient is urban agriculture regarding the food-energy-water nexus?
No full textInternational audienc
Rabbit pluripotent stem cells: a promising and useful biotechnology tool
No full textInternational audienceEmbryo-derived (ESCs) and induced pluripotent stem cells (iPSCs) are both useful biotechnology tools in mice and promising therapeutic agents in humans. In rodents, they made it possible to develop animal models thanks to their ability to produce somatic and germline chimaera. In Humans, they are already involved in clinical trials for several degenerative diseases. Rabbit pluripotent stem cells (rbPSCs) differ from their rodent counterparts but are close to their primate counterparts. In the first part of this article, we describe the state of art of these rabbit cells as well as their future use in biotechnologies for the creationof organoids, bioreactors or animal models of human diseases and for the conservation of biodiversity. In the second part, we present the cryopreservation protocol we have developed in order to freeze rbPSCs without any animal products for health safety reasons
Contribution of artificial waterbodies to biodiversity: A glass half empty or half full?
No full textInternational audienceArtificial ponds are increasingly created for the services they provide to humans. While they have the potential to offer habitats for freshwater biodiversity, their contribution to regional diversity has hardly been quantified. In this study, we assess the relative contribution of five types of artificial ponds to regional biodiversity of five different regions, studying amphibians, water beetles and freshwater snails. This biodiversity is also compared with that observed in natural ponds from three of the investigated regions. Our results indicate that artificial ponds host, on average, about 50% of the regional pool of lentic species. When compared to natural ponds, the artificial ponds always supported a substantially lower alpha richness (54% of the natural pond richness). The invertebrate communities presented high values of beta diversity and were represented by a restricted set of widely distributed species, and by numerous rare species. There were discrepancies among the taxonomic groups: overall, amphibians benefited most from the presence of artificial ponds, since 65% of the regional lentic species pools for this group was found in artificial ponds, whereas 43% and 42% was observed in the case of beetles and snails, respectively. However, each invertebrate group was promptly the most benefited animal group in a single pond type. Therefore, artificial pond types were complementary among them in terms of contribution to regional diversity of the three animal groups. Based on these results, we forecast that future human-dominated landscapes in which most ponds are artificial will be particularly impoverished in terms of freshwater biodiversity, underlining the need to conserve existing natural ponds and to create new “near-natural” ponds. However, if properly designed and managed, artificial ponds could make a substantial contribution to support freshwater biodiversity at a regional scale. Furthermore, the number and diversity of artificial ponds must be high in each considered landscape
Good Pastures, Good Meadows: Mountain Farmers’ Assessment, Perceptions on Ecosystem Services, and Proposals for Biodiversity Management
No full textInternational audienceAn ongoing decrease in habitat and species diversity is occurring in many areas across Europe, including in grasslands in mountain areas, calling for adapted biodiversity management and measures. In this context, we carried out 79 interviews with grassland farmers in five alpine mountain regions in Germany, France, Austria, Italy, and Switzerland. We analyzed farmers’ perceptions about the functions and services of their grasslands, how they qualify “good” grasslands, which grassland management practices have changed over the last 10 years, and proposals to increase species diversity on the farm. They related them primarily to cultural ecosystem services, secondly to provisioning services, and thirdly to regulating and supporting services. Good pastures or meadows were mostly related to composition, quality of forage and productivity, structural criteria, and certain characteristics of soils and topography. The measures for increasing biodiversity that were most frequently proposed were upgrading of forest edges, planting hedges or fruit trees, less or late grassland cutting, reduction or omission of fertilization, and more general extensification of farm productions. Factors hindering the implementation of these measures were mainly increased workload, insufficient time, and a lack of financial means or support to cover additional costs for biodiversity management. These factors have to be taken specifically into account for future policies for enhanced biodiversity management of grasslands, also beyond mountainous areas. Overall, we found that farmers have good but varying knowledge about biodiversity management of their grasslands, but also different perspectives on how to improve it. Here, local initiatives that bring together farmers and flora or fauna specialists to exchange knowledge could be designed and used in participatory pilot schemes to enhance the implementation of improved biodiversity management
Non labour en agriculture biologique : en sol sablo-limoneux, la progression des racines se trouve freinée
No full textInternational audienceQuels sont les effets des différents types de travail du sol sur le système racinaire des cultures céréalières « bio » ? Un long chevelu racinaire est-il gage de meilleure rendement des cultures ? Quinze ans d’un essai mené par l’ISARA sur du blé cultivé en sol sablo-limoneux ont apporté des réponses inattendues
Shared Research Questions on Soil Quality in OF Results of a participatory workshop
No full textInternational audienceIn 2018, a participatory national workshop was organized by ITAB (Organic Food and Farming Technical Institute) and INRA (National Institute for Agricultural Research) in order to highlight issues on soils in Organic Farming (OF) systems. The objectives were: i) to identify the key research questions to be addressed on soils in OF, ii) to make it possible to facilitate network and project building from interactions between academics and stakeholders.Over 150 participants from academic and professional origins attended the workshop which was designed according to The Town Hall Meeting (THM) methodology.High level discussions among participants and panel experts ended up with a list of 20 research questions which confirmed the important lack of knowledge on that topic and the needs for research on the following issues: soils functioning with a focus on biogeochemical cycling and biological interactions; long term effects of agricultural practices, more or less specific to OF; soils protection; tools for soils diagnosis and managemen
Evolutions génétiques du comportement de la lapine et du lapereau évaluées par comparaison de lignées de type ancien et de type moderne dans un dispositif d'adoptions croisées
No full textInternational audienceThe study focused on the estimation of genetic trends for behavior and performances of does and kits during lactation in parallel to 22 generations of selective breeding for litter size and kit growth. The direct effects from the kit (kit line) were separated from the maternal effects of the doe (doe line) with use of a crossfostering design between the old-type (L0) and the modern-type (L22) lines. Does were studied over the two first parities. They raised rabbits from a single kit line. None kit was raised by its biological mother. At d21, L22 females produced more milk than L0 females (250 g vs 206 g, p=0.0003) which resulted in a higher weight of the kits at d21 (378 g vs 340 g, p<0.0001). L22 does had better maternal abilities than L0 does as refered to nest quality (p=0.06), fur puckling (p<0.0001), milk production (p=0.0003) and willingness to nurse (p=0.007). At most dates, more L22 kits were observed out of the nest than L0 kits, whether they were raised by L0 or L22 does. L22 kits exited the nest earlier during lactation and where bolder in an emergence test than L0 kits. Trends in doe behaviour were positive and favorable to litter performance. In advanced lactation, genetics of the kit influenced kit behaviour more than genetics of the nursing dam
Linking changes in the soil microbial community to C and N dynamics during crop residue decomposition
No full textInternational audienceCrop residues are among the main inputs that allow the organic carbon (C) and nutrients to be maintained in agricultural soil. It is an important management strategy that can improve soil fertility and enhance agricultural productivity. This work aims to evaluate the extent of the changes that may occur in the soil heterotrophic microbial communities involved in organic matter decomposition and C and nitrogen (N) mineralization after the addition of crop residues. Soil microcosm experiments were performed at 28°C for 90 days with the addition of three crop residues with contrasting biochemical qualities: pea (Pisum sativum L.), rapeseed (Brassica napus L.), and wheat (Triticum aestivum L.). Enzyme activities, C and N mineralization, and bacterial and fungal biomasses were monitored, along with the bacterial and fungal community composition, by the highthroughput sequencing of 16S rRNA and ITS genes. The addition of crop residues caused decreases in β-glucosidase and arylamidase activities and simultaneous enhancement of the C mineralization and net N immobilization, which were linked to changes in the soil microbial communities. The addition of crop residues decreased the bacterial and fungal biomasses 90 days after treatment and there were shifts in bacterial and fungal diversity at the phyla, order, and genera levels. Some specific orders and genera were dependent on crop residue type. For example, Chloroflexales, Inquilinus, Rubricoccus, Clitocybe, and Verticillium were identified in soils with pea residues; whereas Thermoanaerobacterales, Thermacetogenum, and Hypoxylon were enriched in soils with rapeseed residues, and Halanaerobiales, Rubrobacter, and Volutella were only present in soils with wheat residues. The findings of this study suggest that soil C and N dynamics in the presence of the crop residues were driven by the selection of specific bacterial and fungal decomposers linked to the biochemical qualities of the crop residues. If crop residue decomposition processes showed specific bacterial and fungal operational taxonomic unit (OTU) signatures, this study also suggests a strong functional redundancy that exists among soil microbial communities
