• Energy Research
• 2. Zero hunger close
• FR close
• US close
• CA close
• Hyper Article en Ligne close

Water use efficiency (WUE) is a quantitative measurement which improvement is a major issue in the context of global warming and restrictions in water availability for agriculture. In this study, we aimed at studying the variation and genetic control of WUE and the respective role of its components (plant biomass and transpiration) in a perennial fruit crop. We explored an INRA apple core collection grown in a phenotyping platform to screen one-year-old scions for their accumulated biomass, transpiration and WUE under optimal growing conditions. Plant biomass was decompose into morphological components related to either growth or organ expansion. For each trait, nine mixed models were evaluated to account for the genetic effect and spatial heterogeneity inside the platform. The Best Linear Unbiased Predictors of genetic values were estimated after model selection. Mean broad-sense heritabilities were calculated from variance estimates. Heritability values indicated that biomass (0.76) and WUE (0.73) were under genetic control. This genetic control was lower in plant transpiration with an heritability of 0.54. Across the collection, biomass accounted for 70% of the WUE variability. A Hierarchical Ascendant Classification of the core collection indicated the existence of six groups of genotypes with contrasting morphology and WUE. Differences between morphotypes were interpreted as resulting from differences in the main processes responsible for plant growth: cell division leading to the generation of new organs and cell elongation leading to organ dimension. Although further studies will be necessary on mature trees with more complex architecture and multiple sinks such as fruits, this study is a first step for improving apple plant material for the use of water.

The functional trait framework provides a powerful corpus of integrated concepts and theories to assess how environmental factors influence ecosystem functioning through community assembly. While common in plant ecology, this approach is under-used in microbial ecology. After an introduction of this framework in the context of microbial ecology and enzymology, we propose an approach 1) to elucidate new links between soil microbial community composition and microbial traits; and 2) to disentangle mechanisms underlying “total” potential enzyme activity in soil (sum of 7 hydrolase potential activities). We address these objectives using a terrestrial grassland ecosystem model experiment with intact soil monoliths from three European countries (Switzerland, France and Portugal) and two management types (Conventional-intensive and Ecological-intensive), subjected to 4 rain regimes (Dry, Wet, Intermittent and Normal) under controlled conditions in a common climate chamber. We found tight associations between proxies of microbial ecoenzymatic community-weighted mean traits (enzymatic stoichiometry and biomass-specific activity) and community composition, bringing new information on resource acquisition strategy associated with fungi, Gram positive and Gram negative bacteria. We demonstrate that microbial biomass explained most of the total enzyme activity before altered rain regimes, whereas adjustments in biomass-specific activity (enzyme activity per unit of microbial biomass) explained most variation under altered rain regime scenarios. Furthermore, structural equation models revealed that the variation of community composition was the main driver of the variation in biomass-specific enzyme activity prior to rain perturbation, whereas physiological acclimation or evolutionary adaptation became an important driver only under altered rain regimes. This study presents a promising trait-based approach to investigate soil microbial community response to environmental changes and potential consequences for ecosystem functioning. We argue that the functional trait framework should be further implemented in microbial ecology to guide experimental and analytical design.

The biotechnological development has traditionally focused on the compliance with regulatory demands rather than optimising the processes or analysing their sustainability. This work proposes the combination of available tools for the comprehensive sustainability assessment of a blue biotechnology process based on the cultivation of the microalgae Haematococcus pluvialis. The work aims to include environmental, economic and social dimensions to measure the sustainability of the production of a carotenoid with potential applications in food, nutraceutical, cosmetics and eventually pharmaceutical industries. Electricity for cultivation was identified as the major contributor to the environmental impacts, which depended significantly on the production scale. Social benefits were mainly related to workers and consumers, while the economic assessment suggested a profitable process with a relatively short period to recover the initial investment.

The stark observation of the co-existence of undernourishment, nutrient deficiencies and overweight and obesity, the triple burden of malnutrition, is inviting us to reconsider health and nutrition as the primary goal and final endpoint of food systems. Agriculture and the food industry have made remarkable advances in the past decades. However, their development has not entirely fulfilled health and nutritional needs, and moreover, they have generated substantial collateral losses in agricultural biodiversity. Simultaneously, several regions are experiencing unprecedented weather events caused by climate change and habitat depletion, in turn putting at risk global food and nutrition security. This coincidence of food crises with increasing environmental degradation suggests an urgent need for novel analyses and new paradigms. The sustainable diets concept proposes a research and policy agenda that strives towards a sustainable use of human and natural resources for food and nutrition security, highlighting the preeminent role of consumers in defining sustainable options and the importance of biodiversity in nutrition. Food systems act as complex social–ecological systems, involving multiple interactions between human and natural components. Nutritional patterns and environment structure are interconnected in a mutual dynamic of changes. The systemic nature of these interactions calls for multidimensional approaches and integrated assessment and simulation tools to guide change. This paper proposes a review and conceptual modelling framework that articulate the synergies and tradeoffs between dietary diversity, widely recognised as key for healthy diets, and agricultural biodiversity and associated ecosystem functions, crucial resilience factors to climate and global changes.

Abstract In Europe, grassland is one of the dominant forms of land use. Within 20 years, the area of permanent grasslands and pastures in Western Europe has declined by 12%. Semi-natural grasslands are often hot spots of biodiversity and are threatened both by intensive farming and by the abandonment of farmland in marginal areas. In this review, we show that biodiversity, climate change, C sequestration and farming systems issues are highly interconnected in grassland ecosystems. In this context, there are new risks (induced by climate change), new opportunities (linked to carbon sequestration and biodiversity conservation for example) and new challenges (concerning farm management and agricultural practices) for managed grasslands. An assessment of the current research perspectives underlines some key questions: (i) How to reduce the sensitivity and increase the resilience of grassland biodiversity to heat waves and droughts in an altered climate? (ii) How to protect soil organic carbon stocks under global warming? (iii) How to preserve the habitat for rare or endangered species, while managing the functional diversity of the vegetation for agricultural purposes? (iv) How to maintain the heterogeneity and diversity of grassland vegetation at the farm and landscape levels? (v) How to design innovative farming systems that integrate the impacts of farm activity on biodiversity, water and air quality, fossil energy use and greenhouse gas effect? (vi) How to produce integrated knowledge taking account of the consistency of the different management practices and their feasibility at farm level according to four criteria (profitability, labour, agricultural and environmental performance)?

Significance Bioethanol produced from waste biomass from crops has the potential to provide a sustainable alternative to petroleum-based transportation fuel that does not compete with human food supply. The main obstacle to this approach is the resistance of this biomass to digestion. Thus, expensive energetic pretreatment and high enzyme inputs are needed to increase digestion. In this study, we screened a population of randomly mutated plants for digestibility with the aim of identifying novel factors that impact on this trait. We found a number of mutants with high digestibility and no impairments in growth or fitness. These mutants show a range of alterations in cell-wall composition, and we have mapped and characterized the mutant with the highest increase in digestibility.