Use Of Synthetic Inputs Research Articles

The context‐dependent benefits of organic farming on pollinator biodiversity: A meta‐analysis

Abstract Agricultural intensification is driving declines in pollinator diversity and the degradation of pollination services worldwide. Organic management, which prohibits the use of synthetic inputs, has considerable potential for combatting these declines by enhancing biodiversity in agricultural landscapes. However, the efficacy of organic farming for promoting pollinator diversity has recently been questioned. We conducted a meta‐analysis to determine the effect of organic management on pollinator species richness and abundance. We compiled 42 studies across four continents and calculated a Hedges' g effect size for each of 76 species richness and 57 abundance observations. We then estimated average effect sizes overall and across five moderators. Species richness and abundance of pollinating insects tended to be higher in organic farms than conventional ones, with average effect sizes of 0.68 and 0.74, respectively. Landscape context, crop type, pollinator group, sampling location, and sampling method were factors impacting the response of pollinator diversity/abundance to organic farming. We found benefits for pollinator diversity from organic farming in all landscape types, with the strongest response in simple compared with more complex landscapes. Pollinator diversity benefited the most in habitats within organic cereal systems and the least in organic pastures. Among pollinator groups, bumblebee diversity benefitted the most, while moths and hoverflies showed positive but non‐significant responses. Higher pollinator diversity/abundance was detected in organic farms at various sampling locations. Transect sampling showed the greatest diversity gains among sampling methods. Synthesis and applications. Our results affirm that organic farming has positive effects for pollinator species richness and abundance, but benefits are variable and not guaranteed. We recommend that future studies adopt a standard sampling protocol and cover a larger geographic range to understand the global potential of organic farming to promote pollinator biodiversity. Efforts to increase pollinator abundance and diversity through organic farming should focus on organic systems involving cereal phases, especially within simple landscapes, for the most positive outcomes. However, due to high variability in pollinator responses alongside the challenges to achieve economic profitability from organic farming, crafting organic farming systems to specific farm‐scale opportunities and needs may be necessary.

Green production of apples delivers environmental and economic benefits in China

Sustainable alternative farming systems are gaining popularity worldwide because of the negative effects of conventional agriculture on global climate change and the environmental degradation caused by intensive use of synthetic inputs. The green farming system in China is an integrated production strategy that focuses on reducing chemical fertilizer use while increasing organic manure inputs. Despite their rapid growth as more sustainable systems over the past decades, green farming systems have not been systematically evaluated to date. We used apple production as a representative case to assess the sustainability of green farming systems. Across major apple-producing regions in China, green farming reduced the application of chemical fertilizer nitrogen (N) by 46.8% (from 412 to 219 kg ha−1) and increased that of manure N by 33.1% (from 171 to 227 kg ha−1) on average compared with conventional systems enhancing N use efficiency by 7.27–20.27% and reducing N losses by 8.92%–11.56%. It also slightly lowered yield by 4.34%–13.8% in four provinces. Soil fertility was improved in green orchards through increases in soil organic matter, total N, and available major nutrients. Our cradle-to-farm-gate life-cycle assessment revealed that green farming helped to mitigate greenhouse gas emissions by an average of 12.6%, potentially contributing to a reduction of 165 239 t CO2 eq annually in major apple-producing areas. In addition, green farming achieved 39.3% higher profitability ($7180 ha−1 year−1) at the farmer level. Our study demonstrates the potential of green production of apples for the development of sustainable agriculture in China. These findings advance our understanding of sustainable alternative farming systems and offer perspectives for the sustainable development of global agriculture.

Global challenges and the ‘farm to fork’ strategies of the European Green Deal: Blessing or curse

AbstractThe article evaluates how well the goals of the European Green Deal are justified, especially considering the risks to energy and food security arising from the conflict between Russia and Ukraine. We agree with the objectives of the European Green Agreement as a whole, but whether some of the objectives which feature in the EASAC study can be achieved by 2030 is questionable, and the description of the tools necessary to achieve the objectives is incomplete. Among other things, there is hardly any mention of the role played by precision farming with digitalization, which is a revolutionary change from an ecological and economic point of view, in reducing the use of synthetic inputs, in regenerating the original state of the soil, in reducing GHG emissions, thus in increasing biodiversity, and at the same time in intensifying production, and finally in expanding the application of biotechnology. We examine these areas in our analysis. Some of the objectives of the EASAC study to be achieved by 2030 are subject to debate, and the description of the information and communication conditions necessary to achieve the objectives is incomplete. The IoT (Internet of Things) responds to global and local challenges: it integrates the precision technologies, WSNs (Wireless Sensor Networks), artificial intelligence, mobile field (Smart Small Robots) and remote data loggers (UAVs: Unmanned Air Vehicles and satellites), Big Data, and cloud computing. Consequently, decision support is increasingly developing into unmanned decision making. IoT (Internet of Things) is the basis of “Farm to Fork” and “Lab to Field” monitoring approaches.This article evaluates the implementation of European Green Agreement objectives in light of energy and food security risks arising from the Russia-Ukraine conflict. While overall support for the agreement exists, the feasibility of certain EASAC study objectives by 2030 is called into question due to insufficient tools specifications. Notably absent is the emphasis on precision farming with digitalization, which is a transformative ecological and economic practice. Our analyses look into its function in reducing synthetic inputs, soil regeneration, GHG emission reduction, biodiversity enhancement, production intensification, and biotechnology development. Debates surround EASAC study objectives for 2030, despite limited information and communication restrictions. The Internet of Things (IoT) arises as a solution, combining precision technology, WSNs (wireless sensor networks), AI (artificial intelligence), smart small robots, UAVs (unmanned aerial vehicles), satellites, big data, and cloud computing. As a result, decision support turns toward unmanned decision-making, with IoT laying the groundwork for “Farm to Fork” and “Lab to Field” monitoring systems.

Organic Fertilizers and Bio-Waste for Sustainable Soil Management to Support Crops and Control Greenhouse Gas Emissions in Mediterranean Agroecosystems: A Review

Agriculture is facing several challenges related to its sustainability. In this regard, the need to reduce its environmental impact related to the use of synthetic inputs and its potential role in mitigating global warming and climate change call for a review of crop management. In this context, and in the framework of achieving sustainable development goals, the use of organic fertilizers and bio-waste represents a valuable contribution to the agricultural transition towards a bioeconomy model by reducing the negative impacts of waste disposal. Farmyard manure, composts, digestate from agrifood processes, and biochar are, among organic fertilizers, commonly used to manage soils and support crop growth. These fertilizers can provide essential nutrients, improve structure, and enhance microbial activity, thus increasing soil fertility and agriculture sustainability. While organic fertilizers offer the benefits of soil fertility and plant nutrition, their impact on greenhouse gas (GHG) emissions is complex and varies depending on factors such as fertilizer type, soil conditions, and management practices. Although organic fertilizers may initially increase GHG emissions, they often lead to carbon sequestration in soils highlighting a negative C balance. Additionally, organic fertilizers promote a reduction in fossil fuel consumption used for synthetic fertilizer production, further contributing to GHG emissions’ reduction. Therefore, while organic fertilizers pose challenges in managing GHG emissions, their various benefits warrant careful consideration and strategic implementation in agricultural systems.

Environmental sustainability of Finnish pork production: life cycle assessment of climate change and water scarcity impacts

PurposeThe degrading impacts of livestock production on the environment are well acknowledged. Although ruminants are much studied due to their large contribution to climate change impact, monogastrics are also known to carry a significant load, and mitigation options need investigation. Here, the climate change impact and water scarcity impact of Finnish pork production was investigated using the life cycle assessment approach.MethodsAs the importance of communicating reliable environmental information has been acknowledged in the EU, methods and guidance for this purpose have been developed. Product Environmental Footprint Category Rules have also been published for several food product categories, although not yet for meat. Here, the life cycle assessment methods were used based on PEFCR guidance and the draft version of red meat PEFCR guidance to achieve a reliable, transparent and comparable assessment.ResultsFinnish pork production resulted in a climate change impact of 3.6 kg CO2 eq. kgCW−1 and a water scarcity impact of 0.69 m3 eq. kgCW−1. The largest contribution to the climate change impact came from feed crop production, with an impact of 43%. Land-use changes were included, and their contribution to the Finnish pork climate change impact was 3%. Similarly, in the water scarcity impact, feed crop production was a major contributor, with 41% from fattening pig feed production. Significant contributions to both categories also came from piglet production, including feed crop production, and to the climate change impact from manure storage.ConclusionsFinnish production was seen to already largely utilise sidestreams and domestic feed ingredients, although, e.g. soybean is still used. Based on the results, in mitigating the environmental impacts of Finnish pork production, attention should especially be paid to the resource-efficient production of domestic feed crops and reduced use of organic soils. As current assessment models are unable to grasp the impacts of regenerative farming techniques, the development of LCA methods is also required. Water scarcity impact was seen to be largely affected by the utilisation of feed crops originating from water-scarce countries. As a mitigation measure, the procurement of these feed crops and ingredients should therefore be directed to water-abundant areas and from production which does not depend on irrigation water or the extensive use of synthetic inputs.

A Comprehensive Review on Protected Cultivation of Horticultural Crops: Present Status and Future Prospects

Protected cultivation of horticultural crops has emerged as a crucial technique in modern agriculture, offering numerous benefits such as increased yield, enhanced quality, and protection against adverse climatic conditions and pests. This comprehensive review aims to present the current status of protected cultivation practices and explore its future prospects in horticulture. The review begins by discussing the various types of protected cultivation structures, including greenhouses, high tunnels, and shade houses, along with their advantages and limitations. It then highlights the significance of protected cultivation in addressing global food security challenges by ensuring year-round crop production and reducing dependence on seasonal variations. The review further explores the impact of protected cultivation techniques on the growth and development of horticultural crops, including improved crop morphogenesis, precipitation management, and the optimization of environmental factors such as temperature, humidity, and carbon dioxide levels. Furthermore, the utilization of advanced technologies like hydroponics, aeroponics, and vertical farming within protected cultivation systems is examined, with an emphasis on their potential for maximizing crop productivity while minimizing resource consumption. Moreover, the paper delves into the challenges and constraints faced in implementing protected cultivation, including cost considerations, energy requirements, and the use of synthetic inputs. It discusses sustainable and environmentally friendly approaches, such as utilizing renewable energy sources and adopting organic farming practices, to mitigate these challenges and promote ecological balance. Lastly, the review discusses some future prospects and trends in protected cultivation, including the integration of precision agriculture techniques, the use of artificial intelligence, and the adoption of smart farming technologies. These advancements have the potential to further optimize resource utilization, improve automation, and enhance crop monitoring and management, ultimately leading to greater yield and quality improvements in horticultural crop production.

Ancient varieties can help control weed density while preserving weed diversity

ABSTRACT Weeds are a major component of agricultural diversity affecting crop yield and ecosystem services. Compared to modern wheat (Triticum aestivum) varieties, ancient wheat cultivars (released before 1960) are taller, and this trait can be used to control weeds in organic farming systems. However, there is still a lack of quantitative assessments of the relative contribution of wheat breeding-history (ancient vs modern varieties) and synthetic inputs in explaining weed density and community structure. In this study, a field experiment was undertaken where five modern and five ancient wheat varieties were either treated as in a conventional system with synthetic inputs (nitrogen, herbicide and fungicide) or as in an organic system without the use of synthetic inputs. Crop light interception and weed density were recorded for 12 weeks until crop maturity. On average, ancient varieties reduced weed density by 17% compared with modern varieties, while the application of chemical inputs was responsible for an average reduction of 37%. The stronger competitive effect of ancient varieties was associated with increased sunlight interception. Species richness was higher in the absence of inputs for some weeks, but not by the end of the experiment. The field-based results illustrated that ancient varieties can be used to help control weed density in organic systems that do not rely on synthetic inputs for weed control Despite this effect of crop interference on weed density, a reduction in weed diversity was not observed. These findings could be of particular interest to promote agrobiodiversity in agricultural systems without synthetic inputs.

Variable Importance Without Impossible Data

The most popular methods for measuring importance of the variables in a black-box prediction algorithm make use of synthetic inputs that combine predictor variables from multiple observations. These inputs can be unlikely, physically impossible, or even logically impossible. As a result, the predictions for such cases can be based on data very unlike any the black box was trained on. We think that users cannot trust an explanation of the decision of a prediction algorithm when the explanation uses such values. Instead, we advocate a method called cohort Shapley, which is grounded in economic game theory and uses only actually observed data to quantify variable importance. Cohort Shapley works by narrowing the cohort of observations judged to be similar to a target observation on one or more features. We illustrate it on an algorithmic fairness problem where it is essential to attribute importance to protected variables that the model was not trained on.

Enhanced diversity of aquatic macroinvertebrate predators and biological pest control but reduced crop establishment in organic rice farming

Organic farming has been adopted as the main alternative to reduce the environmental impact of intensive agriculture by banning the use of synthetic inputs and bolstering key ecological functions such as biological pest control. Yet the potential cascading effects of farming management on the communities of natural enemies, the provisioning of pest control, and the ultimate impact on crop performance remain poorly explored. This is especially true for semi-aquatic crops such as rice (Oryza sativa, L) that largely depend on aquatic macroinvertebrate predators for biological pest control. Here we performed two consecutive landscape-scale field experiments by combining monthly surveys of macroinvertebrate aquatic predators with both pest predation and seed rice germination trials to assess differences between conventional and organic rice farming in all the above-mentioned issues. Specifically, we selected 6 organic and 6 conventionally managed rice paddies and evaluated differences in i) the diversity of aquatic macroinvertebrate predators (taxa richness and evenness), ii) the infestation level of a seed pest (chironomids larvae), iii) the efficiency of biological pest control provisioning and iv) the impact on germination of rice seeds. Communities of macroinvertebrate aquatic predators were more diverse (taxa richness) and abundant in organic than in conventional fields, yet community evenness was higher in conventionally-managed fields. Accordingly, we found that macroinvertebrate-mediated pest control was markedly more efficient in organic farms during the establishment crop stage. Pest infestation, however, remained also higher in organic farming, most likely because biological pest control in organic fields is not able to outcompete chemical control provided in conventional fields. Finally, the increased infestation level observed in organic fields ultimately resulted in reduced germination rates of rice seeds, thus limiting crop performance. Our results highlight the potential positive effects of pesticide banning in organic rice farming on aquatic macroinvertebrate communities and the consequently improvement of biological pest control provisioning. Yet conditions enhancing biodiversity may also favor pest infestation and ultimately increase crop damage. Management recommendations should therefore account for potential services and disservices associated to organic farming in order to avoid negative yield outcomes for rice farmers.

Actions speak louder than words: Adoption of sustainable farming practices based on an integrated model

Despite the ample efforts to address the attitude-behavior gap in individual pro-environmental actions, none of the previous research focused on the inconsistency between farmers' attitudes toward organic farming and their decisions to go green. Based on an integrated behavioral model of the TPB (theory of planned behavior) and ABC (attitude-behavior-context) theory, this study provides the first empirical evidence that uncovers the contextual and/or psychological factors driving farmers' attitude-behavior incongruity. The observed attitude-behavior relation indicates that there is a much higher share of conventional farmers exhibit attitude-behavior incongruity compared to their organic counterparts. As predicted by the TPB-ABC model, farmers' tendency to exhibit inconsistency between attitude and behavior is found to increase with their perception of policy support. The working hypothesis that drivers of the discrepancy between farmers' positive attitude and actual adoption behavior are different for the two groups of farmers is also confirmed in this study. Specifically, in addition to the contextual factors, personal capabilities play a role in driving conventional farmers' sustaining use of synthetic inputs and lock-in to unsustainable farming practices. Further analyses of the influence of holding a positive attitude on conventional farmers’ economic performance suggest the presence of economic benefits associated with holding a favorable attitude toward organic farming.

Digitalization, sustainability, and coffee. Opportunities and challenges for agricultural development

CONTEXTDigital technologies have the potential to address several sustainability challenges of the coffee value chain, however, given potential backlash consequences, this process must be assessed thoroughly. Descriptions of digital tools designed for this value chain have been presented in the literature, however, a critical examination of socio-environmental consequences of the process of digitalization is still lacking. OBJECTIVEUsing a socio-technical approach, this article examines innovation pathways proposed by the process of digitalization in the coffee value chain and identifies the opportunities and challenges of these pathways to contribute to sustainability goals in this value chain. METHODSTechnical characteristics of 20 digital tools oriented to the coffee producing sector are examined. We carried out a review of secondary information and conducted online semi-structured interviews with developers of these tools. Qualitative analyses of these characteristics were conducted across three themes: 1) knowledge and value systems represented, 2) power structures, 3) effective use of digital technology. RESULTS AND CONCLUSIONSOur analysis identified two digitalization pathways that are likely to affect different dimensions of sustainability. On the one hand, digital advisory services are focused on the diffusion of conventional agricultural practices to optimize production for a commodity market. On the other hand, trade platforms and traceability systems are associated with enhanced visibility of producers to facilitate their participation in differentiated markets. However, access barriers to technologies create asymmetrical participation of producers in these scenarios. Additionally, evidence shows that, more than a revolution, digitalization of the coffee value chain is about optimization of production based on the use of synthetic inputs and of traditional extension models, and more efficient social coordination within already centralized power structures. SIGNIFICANCEThe analytical framework based on the technical characteristics of digital tools and their interaction with social systems revealed that sustainability outcomes derived from the process of digitalization in the coffee value chain are far from being straightforward. Considering digital technologies not as a homogeneous category, but as a configuration of different technical arrays, each one with distinctive patterns and impacts, provides a more nuanced understanding of the role of digitalization for agricultural development.

Opportunities and challenges for Common Agricultural Policy reform to support the European Green Deal.

The Common Agricultural Policy (CAP) is the European Union's main instrument for agricultural planning, with a new reform approved for 2023-2027. The CAP intends to align with the European Green Deal (EGD), a set of policy initiatives underpinning sustainable development and climate neutrality in the European Union (EU), but several flaws cast doubts about the compatibility of the objectives of these 2 policies. We reviewed recent literature on the potential of CAP environmental objectives for integration with the EGD: protection of biodiversity, climate change mitigation and adaptation, and sustainable management of natural resources. The CAP lacks appropriate planning measures, furthering instead risks to biodiversity and ecosystem services driven by landscape and biotic homogenization. Funding allocation mechanisms are not tailored to mitigate agricultural emissions, decreasing the efficiency of climate mitigation actions. The legislation subsidies farmers making extensive use of synthetic inputs without adequately supporting organic production, hindering the transition toward sustainable practices. We recommend proper control mechanisms be introduced in CAP Strategic Plans from each member state to ensure the EU is set on a sustainable production and consumption path. These include proportional assignment of funds to each CAP objective, quantitative targets to set goals and evidence-based interventions, and relevant indicators to facilitate effective monitoring of environmental performance. Both the CAP and the EGD should maintain ambitious environmental commitments in the face of crisis to avoid further degradation of the natural resources on which production systems stand.

Consociation of Sunflower and Fodder Oilseeds - An Alternative for Mixed Production Systems

The process of agricultural development which takes place in Argentina has led to the loss of sustainability. Mixed systems could be an alternative for improving productivity and, at the same time, taking into account the environmental cost. The sowing of sunflower (Helianthus annus L.) consociated with other species can generate greater biomass and, in some cases, greater yield. Such practice is about the differential harnessing of resources. The aim of this work was to evaluate the production of sunflower consociation with Trifoliumrepens L., Lotus corniculatus, and Vicia sativa, and to determine the conditions of the remaining stubble. Treatments consisted in the use of monoculture sunflower with and without herbicides; intercrop sunflower with red clover, lotus and vicia. The yield of sunflower grain and the total air biomass of the stubble and of its components were evaluated at the time of harvesting, and, two and three months after harvesting. The highest value of available stubble at the time of harvesting was obtained in monoculture sunflower without herbicide. Two months after, there were no variations in the stubble biomass of the treatments. Three months later, there were significant differences registered between the treatments; the intercrops with red clover and lotus reached the highest volume of stubble. Under the conditions of this test, the highest productivity of sunflower was registered when sowed in monoculture and herbicide application was employed. No differences were registered between the intercrops, or between them and the monoculture with herbicide. Therefore, these systems could be considered as a production alternative to lessen the use of synthetic inputs, such as herbicides.

Metagenomics Reveals the Microbiome Multifunctionalities of Environmental Importance From Termite Mound Soils.

The ecological deterioration caused by the continuous and excessive use of synthetic inputs in agriculture has prompted the search for environmentally favorable resources for crop production. Many have advocated for the use of soils from termite mounds to improve soil and plant health; therefore, the purpose of this study was to characterize the microbiome multifunctionalities that are important for plant health and growth in termite mound soil. The metagenomics of soil from termite mounds revealed taxonomic groups with functional potentials associated with promoting the growth and health of plants in nutrient-poor, virtually dry environments. Analysis of microorganisms revealed that Proteobacteria dominated the soil of termite colonies, while Actinobacteria ranked second. The predominance of Proteobacteria and Actinobacteria, the well-known antibiotic-producing populations, indicates that the termite mound soil microbiome possesses metabolic resistance to biotic stresses. Functions recognized for diverse proteins and genes unveiled that a multi-functional microbiome carry out numerous metabolic functions including virulence, disease, defense, aromatic compound and iron metabolism, secondary metabolite synthesis, and stress response. The abundance of genes in termite mound soils associated with these prominent functions could unquestionably validate the enhancement of plants in abiotic and biotically stressed environments. This study reveals opportunities to revisit the multifunctionalities of termite mound soils in order to establish a connection between taxonomic diversity, targeted functions, and genes that could improve plant yield and health in unfavorable soil conditions.

Agroecological practices increase farmers’ well-being in an agricultural growth corridor in Tanzania

Millions of people rely on nature-rich farming systems for their subsistence and income. The contributions of nature to these systems are varied and key to their sustainability in the long term. Yet, agricultural stakeholders are often unaware or undervalue the relevance of those contributions, which can affect decisions concerning land management. There is limited knowledge on how farming practices and especially those that build more strongly on nature, including agroecological practices, may shape farmers’ livelihoods and well-being. We aim to determine the effect that farmer perception of contributions from nature, socioeconomic conditions, and farming practices, have on outcomes related to food security and human well-being. We conducted 467 household surveys in an agricultural growth corridor in rural Tanzania, which is also essential for nature conservation due to its high biodiversity and its strategic location between several protected areas encompassing wetland, forest, and grassland habitats. Results show that implementing more agroecological practices at farm scale has a positive effect on farmer well-being in the study landscape. Results also indicate that higher awareness of benefits from nature, as well as engagement with agricultural extension services, are associated with higher number of agroecological practices applied in the farm. This research confirms the relevance of capacity-building initiatives to scale up the uptake of agroecological practices in the tropics. It also shows, using empirical evidence, that farming practices taking advantage of nature’s contributions to people can positively affect food security and human well-being, even when those practices complement conventional ones, such as the use of synthetic inputs. Understanding the impact of agroecological farming on the well-being of smallholder farmers in the tropics paves the way for policy and program development that ensures global food demands are met in a sustainable way without compromising the well-being of some of the world’s most vulnerable people.

Cognitive resources to promote exploration in agroecological systems design

CONTEXTTo support agroecological transition aimed at sharply reducing the use of synthetic inputs, agricultural systems must undergo in-depth change in which biological processes are enhanced with a view to providing ecosystem services. This transformation of the cropping systems requires design processes which should rely on the exploration of science-based and expert-based knowledge and of alternative solutions (divergence thinking), and on the tailoring of the solution to the situation at hand (convergent thinking). OBJECTIVEOur objective is to build, together with end users, cognitive resources structuring knowledge. These resources will then serve to guide users in the exploration of agroecological solutions that are both disruptive and tailored to the situation in which they will be implemented. METHODSBased on theoretical insights from Design Studies, we first proposed guidelines for building cognitive resources to support divergent and convergent thinking. Based on these guidelines, we built prototypes of cognitive resources, with specific knowledge structures adapted to design reasoning in agriculture: the function-based resource and the biology-based resource, to stimulate divergent thinking in the exploration process; and the experience-based resource to support both convergent and divergent thinking. We then conducted 12 user tests of these prototypes, with various targeted users (advisors, farmers, teachers, researchers) who were either designers of agroecological systems or contributors, eager to use actionable resources to share what they had learnt about innovative systems or their knowledge on ecological processes. We received feedback from the designers who had used the resources in context, and from the contributors who had developed cognitive resources using the suggested guidelines. RESULTS AND CONCLUSIONSOur findings highlight how the resources support agronomist-designers and facilitators in their activities during the exploration part of a design process, from the preparation of design workshops to the stimulation within workshops and the ex-post documentation of a collective exploration for its reuse by other designers. Contributors recognized that the suggested guidelines and prototypes would both help to build on existing knowledge and enable future reuse by designers. They also noted the completeness, the evidence and the value-laden nature of the content. We finally discussed how these cognitive resources could be collectively enriched by a community of practitioners with diverse expectations and values, sharing the common goal of designing agroecosystems conducive to agroecology. SIGNIFICANCEOur research contributes to a critical shift in knowledge capitalization (mixing science-based and experience-based knowledge) to support the design process of agroecosystems, involving various actors, including practitioners.

Exploring national trajectories of organic agriculture in Africa. Comparing Benin and Uganda

Why and how organic agriculture has been developing in Africa is under-studied, especially from a political stance. We explore two contrasting empirical case studies of national organic trajectories: Uganda and Benin. In both countries, organic agriculture emerged in the 1980s around food security stakes and spread in the 1990s through certified export value chains, with a faster development in Uganda than in Benin. From a theoretical perspective, this paper proposes an original analytical grid to study national trajectories of institutionalization of organic farming in Africa, based on three main variables: the policy regime in place in the country (including socio-economic and agrifood dimensions); the relative interest of public and private foreign actors in organic agriculture; and the strength of the national organic agriculture movement. Our results show that the degree of institutionalization of the Green Revolution paradigm in the country is of capital importance for explaining developments in organic farming, particularly its materialization through the increasing use of synthetic inputs: institutionalizing organic farming means deinstitutionalizing agrochemicals. We also show that the high level of extraversion of organic agriculture development in Africa through its focus on certified export value chains raises long-term questions of farmers' empowerment and of local consumers/citizens' access to local organic food. Finally, national organic agriculture movements can play a crucial role by politicizing certain issues in national public debate, such as pesticides' impacts on human and environmental health, and by advising governments in organic policy framing and implementation. Applying the proposed socio-political analytical grid to new national or regional African case studies will help to further enrich the empirical knowledge on organic food and farming in Africa.

Design and multicriteria assessment of low-input cropping systems based on plant diversification in southwestern France

Lengthening and diversifying crop rotations is an efficient strategy to reduce the use of fertilizers and pesticides, thereby improving the sustainability of cropping systems. To test this assumption, six innovative cropping system prototypes were designed, each introducing one or more agroecological practices, as alternatives to the 2-year sunflower (Helianthus annuus L.)–durum wheat (Triticum turgidum L. subsp. durum) rotation widespread in southwestern France. Two 3-year rotations were implemented at INRAE, Toulouse, from 2011 to 2016. The six prototypes were composed of two low-input cropping systems (with/without cover crops) and four very low-input cropping systems (including cultivar or species mixtures, each with/without cover crops). As compared to the sunflower–wheat rotation, the prototypes aimed at reducing the use of N fertilizers by 25% (low-input) and 50% (very low-input) and pesticides by 50%. A set of agronomic, environmental, technical, and socio-economic indicators was calculated to assess the different components of sustainability. The introduction of agroecological principles resulted in a clear reduction of the use of synthetic inputs as compared to the sunflower–wheat rotation. The treatment frequency index was decreased by 56, 18 and 39% for the low-input cropping systems, very low-input cropping systems with cultivar mixtures, and very low-input cropping systems with species mixtures, respectively. However, the profitability decreased with the diversification of cropping systems as the semi-net margin decreased for the three previous cropping systems (745, 696, and 438 €·ha−1, respectively, vs. 963 €·ha−1 for the sunflower-wheat rotation). Despite the costs of inputs, the short rotation remained the most profitable. Agroecological practices succeeded in reducing the dependence of cropping systems on synthetic inputs, but their implementation needs to be improved to achieve better economic performance, using both scientific knowledge and know-how of innovative farmers.

BIOTECHNOLOGICAL POTENTIAL OF SOYBEAN PLANT GROWTH-PROMOTING RHIZOBACTERIA

ABSTRACT Technologies that use rhizobacteria to promote plant growth are increasing in agriculture, results have shown improvements in soil quality, increases in productivity, and decreases in the use of synthetic inputs, The objective of work was to characterize bacterial isolates regarding their biological activity and growth promotion of soybean plants grown in a controlled environment. Fifteen bacteria were isolated from soils with continuous use of biological fertilizer. They were evaluated for enzymes production (amylase and protease), nitrogen fixation, antagonistic activity to phytopathogenic fungi, and indoleacetic acid (IAA) production, Soybean seeds were inoculated with bacterial isolates in a greenhouse and evaluated for plant development and soil chemical attributes. The results showed that 8 of the 15 isolates presented production of amylase, protease, or both and 4 isolates presented nitrogen-fixing capacity. The percentage of isolates with high or moderate inhibitory action against the fungi Sclerotinia sclerotiorum, Macrophomina phaseolina, and Fusarium solani were 73.3%, 66.6%, and 73.3%, respectively. The IAA production varied from 8.56 to 31.33 µg mL-1 (5 isolates had low, 6 had moderate, and 4 had high production). The soybean development was significantly higher in 80% of the treatments with inoculation with bacterial isolates. Five bacterial isolates effectively present all characteristics for use as inoculant (biofertilizer) to promote the development of soybean plants.

Rehabilitation of Heavy Metal Contamination and Soil Erosion Through Integrated Management

Soil is an essential element for life in natural environment. Agricultural and industrial human activities alter the properties of soil, which increase soil erosion and deteriorate the soil fertility. Indiscriminative use of synthetic inputs, improper management, industrialization and urbanization activities increase heavy metal pollution that degrade the natural environment. Excess amount of heavy metal affects plant metabolic activities and enter into food chain process that ultimately affects the health of animals and humans. The issues of soil erosion and heavy metal pollution are very much concerned because of their degradability in natural system. Therefore several management practices are followed to minimize the soil erosion and heavy metal toxicity. Some of the traditional cultural methods are either extremely costly or they are simply applied for short term management. The biological technologies require long period for reclamation. Recently, the application of nanoparticle is used for rehabilitation of natural environment. The effectiveness in controlling soil erosion and heavy metal pollution is more by integrating any of the cultural, biological and nano technological approach than using individually.