68 research outputs found

    Post-Industrial Agriculture: Competing Proposals for the Transformation of Agiculture

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    For many years, scientists have been sounding the alarm that the global ecosystem is in a precarious state and possibly on the verge of abrupt changes due to anthropogenic pressures

    Main challenges and key features of indicator-based agroecological assessment frameworks in the context of international cooperation

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    Agroecology increasingly gains importance in the discussion about sustainable food systems. To facilitate the transition from conventional farming to agroecological farming, adequate methods and concepts to measure and assess impact and productivity of agroecological farming systems (AFSs) are needed, which consider their multifunctionality and other specific characteristics, here called agroecological sustainability assessment frameworks and tools (ASAFTs). In the past years, many agricultural sustainability assessment tools and frameworks were developed but their suitability and applicability to AFSs was not investigated. To close this knowledge gap, we aimed at identifying, reviewing, and discussing published ASAFTs in the context of international cooperation, providing an overview of the current challenges, needs, and requirements in assessing AFSs at the farm level with the means of indicators. Desktop and scientific database research was conducted to identify and discuss published indicator-based ASAFTs at the farm level. The analysis was based on the following four framework elements that the authors considered to be essential for ASAFTs: (1) the adaptability to local conditions all over the world, (2) the involvement of farmers in the development process, (3) the consideration of the multiple functions of an agroecosystem in the definition and measurement of its productivity, and (4) the accounting for interactions between multiple agroecosystem functions and their measurement. Only a few analyzed assessment frameworks at least partly consider these essential elements and were designed specifically for AFSs. However, our study also showed that these frameworks were (1) restricted in their geographical application scope, (2) quite heterogeneous and barely comparable, and (3) based on productivity indicators that do not fully capture the multiple functions of AFSs. Therefore, we identified the need for the development of appropriate agroecological productivity indicators and common standard or reference frameworks for assessing AFSs, which will be crucial for upscaling agroecology

    Identifying indicator species for post-release monitoring of genetically modified, herbicide resistant crops

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    In Europe, regulations for release and placing-on-the-market of genetically modified (GM) crops require post-release monitoring of their impact on the environment. Monitoring potential adverse effects of GM crops includes direct effects as well as indirect effects, e.g. GM crop specific changes in land and pest management. Currently, there is a gap in the pre-release risk assessments conducted for regulatory approval of GM herbicide resistant (HR) crops. Since the relevant non-selective herbicides have been registered many years ago, in current dossiers requesting regulatory approval of GM HR crops, the environmental impacts of the corresponding non-selective herbicides are either entirely omitted or the applicant simply refers to the eco-toxicological safety assessments conducted for its original pesticide approval that do not address environmental issues arising in conjunction with the cultivation of GM HR crops. Since the ‘Farm-scale Evaluations', it is clear that consequences for farmland biodiversity can be expected. The objective of this project was to identify relevant indicator species for the long-term impact of GM HR maize cultivation and the application of their corresponding non-selective herbicides, glyphosate and glufosinate. In this article, we describe the outcome of a modified Event Tree Analysis, essentially a funnel-like procedure allowing to reduce the large number of potentially affected non-target species to those with greatest ecological relevance and highest risk to be adversely affected based on a number of ecological criteria. This procedure allowed us to identify a total of 21 weed-Lepidoptera associations that we proposed for post release monitoring of GM HR maize in German

    Simulating evolutionary responses of an introgressed insect resistance trait for ecological effect assessment of transgene flow: a model for supporting informed decisionmaking in environmental risk assessment

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    Predicting outcomes of transgene flow from arable crops requires a system perspective that considers ecological and evolutionary processes within a landscape context. In Europe, the arable weed Raphanus raphanistrum is a potential hybridization partner of oilseed rape, and the two species are ecologically linked through the common herbivores Meligethes spp. Observations in Switzerland show that high densities of Meligethes beetles maintained by oilseed rape crops can lead to considerable damage on R. raphanistrum. We asked how increased insect resistance in R. raphanistrum – as might be acquired through introgression from transgenic oilseed rape – would affect seed production under natural herbivore pressure. In simulation experiments, plants protected against Meligethes beetles produced about twice as many seeds as unprotected plants. All stages in the development of reproductive structures from buds to pods were negatively affected by the herbivore, with the transition from buds to flowers being the most vulnerable. We conclude that resistance to Meligethes beetles could confer a considerable selective advantage upon R. raphanistrum in regions where oilseed rape is widely grown

    Tritrophic Interactions of Transgenic Bacillus thuringiensis Corn, Anaphothrips obscurus (Thysanoptera: Thripidae), and the Predator Orius majusculus (Heteroptera: Anthocoridae)

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    Laboratory feeding experiments using transgenic Bacillus thuringiensis variety kurstaki (Berliner) corn plants were carried out to study the effects of B. thuringiensis-fed herbivorous prey on the predator Orius majusculus (Reuter). Host plants were a transgenic B. thuringiensis-expressing (Cry1Ab) corn hybrid and the corresponding untransformed isogenic B. thuringiensis-free corn hybrid. The herbivorous prey species used in the experiment was Anaphothrips obscurus (Müller), a thysanopteran pest of corn, not sensitive to Cry1Ab toxin. The objectives were to quantify the effects of B. thuringiensis-fed prey on the development and mortality of immature O. majusculus. There was no significant difference in total mean mortality from hatch to adult eclosion between O. majusculus nymphs reared on B. thuringiensis-fed or B. thuringiensis-free prey. Similarly, no significant differences in total developmental time of O. majusculus was detected when reared on the two different prey types. Overall mortality was low, confirming that the methodology used was appropriate. We propose this approach as an efficient standardized preregistrational testing for side effects of transgenic plants on small predators such as Orius sp

    Effects of Activated Bt Transgene Products (Cry1Ab, Cry3Bb) on Immature Stages of the Ladybird Adalia bipunctata in Laboratory Ecotoxicity Testing

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    Insect-active Bacillus thuringiensis (Bt) proteins are expressed by several transgenic crop plants to control certain pests, but nontarget organisms such as ladybirds also can be exposed to these proteins in the field. We developed an improved ecotoxicity testing protocol and conducted feeding trials in a laboratory setting to test for possible adverse effects of different concentrations of microbially produced trypsin-activated Cry1Ab and Cry3Bb toxins on the coccinellid Adalia bipunctata. Larval/pupal mortality, development time, and overall body mass accumulation were recorded. Even at the lowest concentration (5 μg/ml), A. bipunctata larvae fed with the lepidopteran-active Cry1Ab toxin exhibited significantly higher mortality than the control group. In experiments with the coleopteran-active Cry3Bb, only a concentration of 25 μg/ml resulted in a marginally significantly higher mortality compared to the control. Both experiments revealed a slight decline in mortality at the highest concentration of 50 μg/ml, though this was statistically significant only in the Cry1Ab treatment. No differences were detected for development time and body mass of newly emerged adults. Dilutions of the expression vector pBD10—used as a control to exclude effects of the toxin production method—at concentrations between 10 and 100 μg/ml revealed no significant effects on either of the studied parameters. This suggests that the increased mortality of larvae in the toxin feeding trials was caused directly by the activated Bt toxins and raises questions regarding their commonly postulated specificity and their mode of action in A. bipunctata. Implications of the reported results for ladybird populations and their biological pest control functions in transgenic crop ecosystems are discusse

    Ict4Agroecology - A Farmer Participatory Research Project In Tanzania

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    The role of technologies to support a transition to agroecological production systems is becoming increasingly important(e.g. digital or biotechnological technologies). Technologies are often assigned the role of a key driver of change wherethe proposed, mostly proprietary technologies shape the change process and require adaptation of the farmer and theproduction system to the technology in order to allow the technology to realize its maximum potential. We place the focuson the farmer and the agroecological production systems and retool digital technologies to support the farmers inrealizing the maximum potential of their agroecological production systems. Here, we present the current outcomes of theResearch and Advocacy on Agroecology program, coordinated by Swissaid Tanzania, and implemented by national andinternational partners, including Sustainable Agriculture Tanzania (SAT), Sokoine University of Agriculture (SUA) and theSwiss Federal Institute of Technology (ETH)

    Toxicity of Bacillus thuringiensis CrylAb Toxin to the Predator Chrysoperla carnea (Neuroptera: Chrysopidae)

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    Laboratory feeding studies were carried out to determine the effects of the Bacillus thuringiensis (Berliner) CrylAb toxin on developmental time and mortality of Chrysoperla carnea (Stephens) larvae. A bioassay technique was developed that allowed for incorporation of the CrylAb toxin into a liquid diet that was then encapsulated within small paraffin spheres. Because only 2nd and 3rd instars can penetrate the surface of the paraffin spheres, 2 different methods were used to rear chrysopid larvae through the 1st instar. The 1st method used small foam cubes soaked in non-encapsulated, liquid diet (with or without CrylAb). The 2nd method used Ephestia kuehniella (Hübner) eggs as prey during the first instar (no CrylAb exposure). After reaching the 2nd instar, all larvae received encapsulated, artificial diet with or without CrylAb, respectively. When reared only on artificial diet containing CrylAb toxin, total immature mortality was significantly higher (57%) than in the respective untreated control (30%). Also, significantly more chrysopid larvae died (29%) that received CrylAb later during their larval development compared with the respective control (17%). Although mortality was consistently higher, no or only small differences in developmental times were observed between CrylAb-treated and untreated C. carnea larvae. C. carnea larvae required significantly more time to complete larval development when reared on artificial diet only than when reared first on E. kuehniella eggs followed by encapsulated artificial diet or on only E. kuehniella eggs, regardless of exposure to CrylAb. These results demonstrate that CrylAb is toxic to C. carnea at 100 μmg/ml of diet by using encapsulated artificial die

    Feeding the People: Agroecology for Nourishing the World and Transforming the Agri-Food System

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    Agroecology is an idea inspiring more and more people, but it means different things to different people. Altieri (1983) defined it as the application of ecological principles to agriculture. This definition of agroecology includes farmers and farmers’ knowledge, and it sees farmers as stewards of the landscape, of biodiversity and of the diversity of foods. In 2002, Altieri developed his concept further when he proposed that agroecological systems should be based on five ecological principles: 1) recycling biomass and balancing nutrient flows and availability; 2) securing favourable soil conditions for plant growth by enhancing the organic matter; 3) minimizing losses of solar radiation, water and nutrients by managing the microclimate and soil cover, and practising water harvesting; 4) enhancing biological and genetic diversification on cropland; and 5) enhancing beneficial biological interactions and minimizing the use of pesticides

    Digital Reset: Redirecting Technologies for the Deep Sustainability Transformation

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    Governments worldwide hope that digital technologies can provide key solutions. Yet this report shows that digitalisation, in its current and mainstream form, is rather aggravating than solving many of the pressing social and environmental crises at hand. What is needed instead is a deep sustainability transformation that fundamentally reorganises the economy and all its sectors - agriculture, mobility, energy, buildings, industry, and consumption. The Report »Digital Reset« shows how digital technologies can support the quest for such a deep sustainability transformation. The report provides a blueprint for the European Union on how to reconceptualise digitalisation so that it first and foremost contributes to achieving carbon neutrality, resource autonomy and economic resilience while supporting equity and fully respecting citizen's rights and privacy. The report is the outcome of a two-year international science-policy dialogue, »Digitalization for Sustainability« (D4S), and presents an up-to-date comprehensive analysis of opportunities, risks and governance options regarding digitalization and sustainability
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