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Early pedogenesis of a young Technosol made from organic wastes
No full textInternational audienceConstructed soils based on urban waste, i.e. Technosols appear as a promising solution to enhance circular economy while delivering ecosystem services. Their ability to provide such services depend on their constitution as well as on their temporal evolution and pedogenesis, which is poorly known. We studied during three years the changes in an isolatic Technosol made essentially of organic urban wastes.The study took place on a Parisian rooftop with an experimental trial of 24 plots. We compared four Technosols with similar upper layers (a mix of biowaste compost and spent mushroom substrate), but with either a mineral (shredded tiles and bricks) or an organic lower layer (shredded wood). Both types were run with and without plants. Technosols were monitored over three years and samples were taken at different times to study pedogenetic processes.We observed a rapid and sharp volume loss of the Technosols, responsible for an important mass loss, but not leading to any increase in bulk density. A clear physico-chemical differentiation of treatments from the parent materials appeared after one and three years. The Technosoil organic C stocks decreased over time. During three years, all Technosols were a net source of nitrogen and dissolved organic carbon, released in the drainage waters. Identified pedogenesis processes were the same as in natural soils, but the changes were very fast. The key equilibrium between mineralisation of organic matter and its stabilization that must be ensured when creating such Technosols. They show the necessity for long term research on the development of Technosols
Combining diversified prairies with wheat to promote beneficial plant-soil ecological interactions and the coupling of carbon and nitrogen biogeochemical cycles in agroecosystems
No full textInternational audienceMobilizing plant functional diversity appears as a promising avenue to promote agroecosystems multifunctionality and stability in order to face agriculture challenges in terms of production, limitation of inputs, conservation of soils, and mitigation of greenhouse gases emissions. In natural or semi-natural ecosystems, a high level of plant functional diversity might trigger beneficial plant-soil ecological interactions, leading to several mechanisms of coordination over time between plant nutrient demand and soil offer (i.e., “synchrony”). As perennial prairies can reach a considerable degree of functional diversity within a small area, their implementation with crops can be a precious lever to promote such mechanisms. Among those, a seasonal scale coordination between plants nutrient demand and the relative balance between microbial construction and microbial decomposition of Soil Organic Matter (SOM) was associated with prairies encompassing fast-growing species. This leads to improved plant primary productivity combined with reduced nutrient losses, and increased microbial originated carbon (C) storage in the soil. Moreover, the modulation of nitrogen (N) symbiotic fixation depending on photosynthesis activity by legumes within the prairies allows N enrichment of the agroecosystem. We conceived an experimental design with new agroecosystems called “agroprairies” which gather perennial diversified prairies and winter wheat (Triticum aestivum) cultivated in alternating bands. Four functionally different prairies were designed to vary across nutrient acquisition strategies and proportion of legumes. The experiment also included plots with each cover grown alone, as well as a perennial crop (Thinopyrum intermedium). We explored the effects of plant functional diversity on soil biogeochemical C and N cycles and soil microbial communities and activities. We conducted measurements of plant production, soil microbial C dynamics (microbial C use efficiency, soil microbial respiration, microbial biomass, microbial growth), five hydrolytic or oxidative exoenzyme activities related to C, N and phosphorus (P) cycles and abundances of the soil microbial communities (bacteria, archaea and fungi). These measurements were performed in January 2024 during winter at a time where plant nutrient demand is low, and in May 2024 at the maximum plant biomass production. We found that soil biogeochemical C and N cycles and abundances and activities of microbial communities strongly varied between January and May, and that some of these variables, as well as the production of wheat differed depending on the functional characteristics of the prairies
Systemic Acquired Resistance: Plant Priming for Ecological Management of Mealybug-Induced Wilt in MD2 and Queen Victoria Pineapples
No full textInternational audiencePineapples are highly susceptible to "Wilt disease", caused by the biotrophic insect Dysmicoccus brevipes that also transmits several Wilt-associated viruses (PMWaVs). Conventional farms manage mealybugs and Wilt disease using chemicals. However, many of these chemicals have been banned in Europe due to safety concerns, leading to a critical need for studies on pesticide-free control methods. During their evolution, plants have developed natural defences, such as systemic acquired resistance (SAR), against pathogens and pests. In this study, salicylic acid (10 -3 M) was applied to MD2 and Queen Victoria pineapple plants as a foliar spray or soil drench, followed by mealybug infestation. This treatment enhanced defences, assessed through mealybug multiplication rates, and biochemical and molecular responses of tissue-cultured plantlets under controlled conditions. Phenylalanine ammonia-lyase activity (PAL) was measured as a potential SAR signalling enzymatic marker. Additionally, the expression levels of four genes were analyzed, which included AcPAL and AcICS2, both linked to salicylic acid synthesis; AcMYB-like, a transcription factor regulating salicylic acid biosynthesis; and AcCAT, which is involved in H 2 O 2 level control in plants. SA elicitation reduced the mealybug multiplication rate by 70% on pineapples compared to untreated plants. In this study, the biochemical marker (PAL) and three molecular markers (AcPAL, AcICS2, and AcCAT) showed significant differences between primed and unprimed plants, indicating SAR induction and its role in the pineapple-mealybug interaction. In MD2 and Queen Victoria, PAL increased by 2.3 and 1.5, respectively, while AcPAL increased by 4 and more than 10. The other molecular markers, AcICS2, AcCAT, and AcMYB-like (a transcription factor), increased by 3, except for the last one in Queen Victoria. The reduction in mealybug populations with SAR is less effective than with pesticides, but it provides a valuable alternative on Réunion Island, where the only remaining insecticide will soon be banned. In addition, SAR priming offers a promising, eco-friendly strategy for managing mealybug populations and reducing Wilt disease in pesticide-free pineapple cropping systems.</div
Prediction of marbling score in ribeye quartered at the 5th- 6th rib of French beef using the Q-FOM™ beef assessment camera
No full textInternational audienceIn the Meat Standards Australia (MSA) and Guaranteed Global Grading (3G) grading schemes, beef marbling isscored visually in the chiller by accredited graders from 100 to 1190 marble score points in increments of 10.This study aimed to evaluate a hand-held camera (Q-FOM™ Beef) for determining MSA marbling scores ofcarcasses quartered between the 5th and 6th rib. The carcasses were scored by two accredited graders, includingan expert grader (i.e. a more experienced grader). The R2 of correlation between scores of the two graders for 377carcasses was 0.78 with a RMSE of 47.9. The R2 of correlation between the scores of the expert grader and the QFOM™ for 285 carcasses was 0.75 with a RMSE of 44.9. For the grader-to-grader comparison, 75.9 %, 97.1 %and 100 % of the values were within 50, 100 and 200 marbling points, respectively. For the comparison betweenQ-FOM™ predictions and the expert grader, 78.6 %, 96.8 % and 99.7 % of the values were within 50, 100 and200 marbling points, respectively. Both between visual graders and the Q-FOM™ against expert grader showedacceptable accuracy performance and fulfilled the accreditation criteria defined by AUS-MEAT in Australia.Additionally, 124 Q-FOM™ images were assessed on-screen by the expert grader. The R2 of correlation betweenthe in-chiller and on-screen MSA marbling scores was 0.78 with a RMSEP of 48.7. Thus, on-screen assessing metrequirements for accreditation, and both in-chiller and on-screen visual assessments of MSA marbling score areacceptable inputs for developing a Q-FOM™ Beef marbling model
Review: Will “cultured meat” transform our food system towards more sustainability?
No full textInternational audienceOur agri-food system today should provide enough healthy food of good quality for the growing human population. However, it should also preserve natural resources and better protect livestock. In this context, some FoodTech companies are developing a disruptive approach: cell culture for in vitro food production of “meat” but this technology is still at the research and development stage. This article will highlight its development, the technologies used and the stakeholders involved (Part 1), its potential environmental impacts (Part 2) but also regulatory, social and ethical issues (Part 3). This article aims to shed light throughout the manuscript on two major controversies related to “cultured meat”. The first controversy is related to its ethical aspects, which includes different points: its potential to reduce animal suffering and therefore to improve animal welfare, the future values of our society, a trend towards food artificialisation. The second controversy includes environmental, health and nutritional issues, in relation to characteristics and quality of “cultured meat” with an important question: should we call it meat? These two controversies act in interaction in association with related societal, legal and consequently political issues. Answers to the various questions depend on the different visions of the World by stakeholders, consumers and citizens. Some of them argue for a moderate or a strong reduction in livestock farming, or even the abolition of livestock farming perceived as an exploitation of farm animals. Others only want a reduction of the current much criticised intensive/industrial model. Compared with other potential sustainable solutions to be implemented such as reduction of food losses and waste, new food consumption habits with less proteins of animal sources, sustainable intensification, development of agroecological livestock production, or the development of the market for other meat substitutes (proteins from plants, mycoproteins, algae, insects, etc.), “cultured meat” has an uncertain future
Agroecological Living Labs as entry points for transition towards sustainable food systems: a novel framework for the evaluation of living labs at different scales
No full textInternational audienceAgroecological transitions are vital for creating resilient and sustainable food systems, as they balance ecological processes with social dynamics. Stakeholder engagement and collective innovation are essential drivers of these transitions and Agroecological Living Labs (ALLs) have emerged as promising platforms for inclusive, multi-actor collaboration that foster co-creation and knowledge sharing. This study introduces the ME4ALL framework -a structured tool designed to help ALLs assess their activities and impacts, align their efforts with the 13 principles of agroecology, and support participants in reflecting on their strategies, evaluating interactions, and identifying areas for improvement. Focusing on three ALLs located in Italy, the Netherlands, and the United Kingdom, our evaluation reveals that while ALL activities are linked to multiple agroecological principles, the degree of alignment is shaped more by national context than by scale. Notably, access to funding emerges as a scale-dependent factor, and political impacts -such as policy adjustments and enhanced dialogue with policymakers -are more pronounced at national and regional levels. By advancing our understanding of ALLs -their similarities, diversity and roles in agroecological transitions -this study offers both theoretical and practical contributions, providing a framework for comparing ALLs across local, regional and national scales
Seasonal allocation of dry matter and nitrogen in Th. intermedium across stand ages
No full textInternational audienceThinopyrum intermedium is currently proposed as a perennial grain for both forage and grain production. Undergoing domestication, its grain yields are low, while its long-lasting organs are ensuring environmental benefits. However, understanding the resource allocation dynamics of Th. intermedium is needed. Dry matter (DM) and nitrogen (N) allocations within the different plant parts were quantified over the growing season on various experimental sites and stand ages. Low resource mobilization to spikes was observed after flowering, contrarily to N allocation within stem bases. Indeed, root production and stem bases thickening over the years represented significant N sinks. In addition, the total N within the plant, weakly allocated to spikes (i.e., 10–26 %), can decrease at the end of the growing season (i.e., from 34 to 56 kg ha−1). This could be explained by root turnover and release of N-rich root exudates to the soil. With a low exportation of N at grain maturity, averaging 60 kg ha−1, a strategy of nutrient conservation was highlighted. Furthermore, through a small proportion of rhizomes, Th. intermedium is characterized by a conservative phalanx growth strategy. However, plant growth conditions could modulate rhizomes’ production as variation within varying stand densities were observed. Finally, we observed an increase of allocation to stem bases in older stands, coupled to a decrease of the reproductive allocation through lower proportion of reproductive tillers. Thus, work dedicated to understanding the allocation of resources in the plant will be beneficial to help identify possible synergies and trade-offs between grain production and ecological services
Editorial: Challenges of food and feed for the future
No full textInternational audienceThis article is part of a supplement entitled Selected keynote lectures of the “Challenges of Food and Feed for the Future” workshop (Lyon, France) supported by the animal Consortium.The “Food and Feed for the Future” workshop, sponsored by the OECD Cooperative Research Programme on Sustainable Agricultural and Food Systems and organised by the French Animal Production Federation (AFZ), INRAE and CSIRO, was held on the 1st of September 2023 at ISARA in Lyon (France). The proceedings are available as a PDF eBook (https://doi.org/10.25719/AFZ.2024.001). The workshop was aimed at all stakeholders interested in understanding and forecasting the future of food and feed, and provided an opportunity to present and discuss the challenges and opportunities for protein production from animals, plants and novel protein sources (such as insects, yeast, microalgae, cellular agriculture) and their contribution to the development sustainable food systems. The present supplement includes a selection of five invited papers presented during the workshop
Perennial Kernza cropping promotes rhizosphere microbiome stability and endophyte recruitment compared to annual wheat
No full textInternational audienceBackground Perennial cropping systems are increasingly recognized for their potential to enhance microbial biodiversity and beneficial soil functions compared to annual crops. The impact of perennialization on the rhizomicrobiome and endophyte community was assessed by comparing intermediate wheatgrass (Thinopyrum intermedium, commercialized as Kernza®, hereafter called 'Kernza') and annual wheat (Triticum aestivum) associated communities across a north-south European agroclimatic gradient (Sweden, Belgium, and France) over two growing seasons and at two depths. ResultsBetween the 2 years, the Kernza-associated rhizomicrobiome was more stable and exhibited greater homogeneity across depths compared to annual wheat. Kernza harboured a significantly more diverse set of crop-associated amplicon sequence variants (ASVs) and had a higher number of core ASVs than annual wheat. Furthermore, Kernza had a significantly higher proportion of rhizobacterial populations in root tissues than annual wheat. Environment-wide association analyses revealed that the Kernza rhizosphere had higher proportions of grassland-associated and rhizosphere-dwelling microbiomes compared to annual wheat. Despite these noteworthy differences, the greatest variation in the rhizomicrobiome composition was driven by factors such as country, year, and depth, rather than crop type. For instance, Actinobacteriota dominated rhizobacterial communities in both Kernza and annual wheat.Conclusions Overall, Kernza conferred modest yet clear improvements in rhizomicrobiome community stability and selective endophyte recruitment, supporting its ability to enhance sustainable, microbially-mediated soil functions. Moreover, Kernza hosted significant grassland-associated taxa, suggesting a similarity between Kernza fields and grassland ecosystems.</div
Perceptions of food waste: is there a numerosity bias?
No full textInternational audienceWhile individuals are expected to perceive similarly identical quantities, regardless of the used units (e.g., 1 ton or 1000 kg), several scholars suggest that consumers over-infer quantities when they are presented in bigger and phonetically longer numbers. In two experimental studies, we examine this numerosity bias in the context of household food waste. Unlike previous scholars, manipulating numerosity revealed no effect: perceptions of food waste volume and likelihood to reduce it are not influenced by the used numeric value (2500 g vs. 2.5 kg; Study 1) nor the number of syllables (two kilos eight hundred seventy-five grams vs. three kilograms; Study 2)