Showing papers on "Organic farming published in 2018"

Thirteen decades of antimicrobial copper compounds applied in agriculture. A review

Abstract: Since the initial use of Bordeaux mixture in 1885 for plant disease control, a large number of copper-based antimicrobial compounds (CBACs) have been developed and applied for crop protection. While these compounds have revolutionized crop protection in the twentieth century, their continuous and frequent use has also raised concerns about the long-term sustainability of copper (Cu)-based crop protection system. Here, we review CBACs used in crop protection and highlight their benefits and risks, and potential for their improvement and opportunities for further research to develop alternatives to CBACs. The major findings are (i) the relatively high toxicity to plant pathogens, low cost, low mammalian toxicity of the fixed Cu compounds, and their chemical stability and prolonged residual effects are major benefits of these compounds; (ii) phytotoxicity, development of copper-resistant strains, soil accumulation, and negative effects on soil biota as well as on food quality parameters are key disadvantages of CBACs; (iii) regulatory pressure in agriculture worldwide to limit the use of CBACs has led to several restrictions, including that imposed by the regulation 473/2002 in the European Union; and (iv) mitigation strategies to limit the negative effects of CBACs include their optimized use, soil remediation, and development and application of alternatives to CBACs for a sustainable crop protection. We conclude that recent research and policy efforts have led to the development of a number of alternatives to CBACs, which should be further intensified to ensure that growers have sufficient tools for the implementation of sustainable crop protection strategies.

A global meta-analysis of yield stability in organic and conservation agriculture

Abstract: One of the primary challenges of our time is to enhance global food production and security. Most assessments in agricultural systems focus on plant yield. Yet, these analyses neglect temporal yield stability, or the variability and reliability of production across years. Here we perform a meta-analysis to assess temporal yield stability of three major cropping systems: organic agriculture and conservation agriculture (no-tillage) vs. conventional agriculture, comparing 193 studies based on 2896 comparisons. Organic agriculture has, per unit yield, a significantly lower temporal stability (−15%) compared to conventional agriculture. Thus, although organic farming promotes biodiversity and is generally more environmentally friendly, future efforts should focus on reducing its yield variability. Our analysis further indicates that the use of green manure and enhanced fertilisation can reduce the yield stability gap between organic and conventional agriculture. The temporal stability (−3%) of no-tillage does not differ significantly from those of conventional tillage indicating that a transition to no-tillage does not affect yield stability.

Organic Agriculture, Food Security, and the Environment

Abstract: Organic agriculture is often perceived as more sustainable than conventional farming. We review the literature on this topic from a global perspective. In terms of environmental and climate change effects, organic farming is less polluting than conventional farming when measured per unit of land but not when measured per unit of output. Organic farming, which currently accounts for only 1% of global agricultural land, is lower yielding on average. Due to higher knowledge requirements, observed yield gaps might further increase if a larger number of farmers would switch to organic practices. Widespread upscaling of organic agriculture would cause additional loss of natural habitats and also entail output price increases, making food less affordable for poor consumers in developing countries. Organic farming is not the paradigm for sustainable agriculture and food security, but smart combinations of organic and conventional methods could contribute toward sustainable productivity increases in global agricul...

Risks and opportunities of increasing yields in organic farming. A review

Abstract: Current organic agriculture performs well in several sustainability domains, like animal welfare, farm profitability and low pesticide use, but yields are commonly lower than in conventional farming. There is now a re-vitalized interest in increasing yields in organic agriculture to provide more organic food for a growing, more affluent population and reduce negative impacts per unit produced. However, past yield increases have been accompanied by several negative side-effects. Here, we review risks and opportunities related to a broad range of sustainability domains associated with increasing yields in organic agriculture in the Northern European context. We identify increased N input, weed, disease and pest control, improved livestock feeding, breeding for higher yields and reduced losses as the main measures for yield increases. We review the implications of their implementation for biodiversity, greenhouse gas emissions, nutrient losses, soil fertility, animal health and welfare, human nutrition and health and farm profitability. Our findings from this first-of-its-kind integrated analysis reveal which strategies for increasing yields are unlikely to produce negative side-effects and therefore should be a high priority, and which strategies need to be implemented with great attention to trade-offs. For example, increased N inputs in cropping carry many risks and few opportunities, whereas there are many risk-free opportunities for improved pest control through the management of ecosystem services. For most yield increasing strategies, both risks and opportunities arise, and the actual effect depends on management including active mitigation of side-effects. Our review shows that, to be a driving force for increased food system sustainability, organic agriculture may need to reconsider certain fundamental principles. Novel plant nutrient sources, including increased nutrient recycling in society, and in some cases mineral nitrogen fertilisers from renewable sources, and truly alternative animal production systems may need to be developed and accepted.

Can Organic Sources of Nutrients Increase Crop Yields to Meet Global Food Demand

Abstract: Meeting global demand of safe and healthy food for the ever-increasing population now and into the future is currently a crucial challenge. Increasing crop production by preserving environment and mitigating climate change should thus be the main goal of today’s agriculture. Conventional farming is characterized by use of high-yielding varieties, irrigation water, chemical fertilizers and synthetic pesticides to increase yields. However, due to either over- or misuse of chemical fertilizers or pesticides in many agro-ecosystems, such farming is often blamed for land degradation and environmental pollution and for adversely affecting the health of humans, plants, animals and aquatic ecosystems. Of all inputs required for increased agricultural production, nutrients are considered to be the most important ones. Organic farming, with use of organic sources of nutrients, is proposed as a sustainable strategy for producing safe, healthy and cheaper food and for restoring soil fertility and mitigating climate change. However, there are several myths and controversies surrounding the use of organic versus inorganic sources of nutrients. The objectives of this paper are: (i) to clarify some of the myths or misconceptions about organic versus inorganic sources of nutrients and (ii) to propose alternative solutions to increase on-farm biomass production for use as organic inputs for improving soil fertility and increasing crop yields. Common myths identified by this review include that organic materials/fertilizers can: (i) supply all required macro- and micro-nutrients for plants; (ii) improve physical, chemical and microbiological properties of soils; (iii) be applied universally on all soils; (iv) always produce quality products; (v) be cheaper and affordable; and (vi) build-up of large amount of soil organic matter. Other related myths are: “legumes can use entire amount of N2 fixed from atmosphere” and “bio-fertilizers increase nutrient content of soil.” Common myths regarding chemical fertilizers are that they: (i) are not easily available and affordable, (ii) degrade land, (iii) pollute environment and (iv) adversely affect health of humans, animals and agro-ecosystems. The review reveals that, except in some cases where higher yields (and higher profits) can be found from organic farming, their yields are generally 20–50% lower than that from conventional farming. The paper demonstrates that considering the current organic sources of nutrients in the developing countries, organic nutrients alone are not enough to increase crop yields to meet global food demand and that nutrients from inorganic and organic sources should preferably be applied at 75:25 ratio. The review identifies a new and alternative concept of Evergreen Agriculture (an extension of Agroforestry System), which has potential to supply organic nutrients in much higher amounts, improve on-farm soil fertility and meet nutrient demand of high-yielding crops, sequester carbon and mitigate greenhouse gas emissions, provide fodder for livestock and fuelwood for farmers and has potential to meet global food demand. Evergreen Agriculture has been widely adapted by tens of millions of farmers in several African countries and the review proposes for evaluation and scaling-up of such technology in Asian and Latin American countries too.

Evidence that organic farming promotes pest control

Abstract: Ecological intensification of agro-ecosystems, based on the optimization of ecological functions such as biological pest control, to replace agrochemical inputs is a promising route to reduce the ecological footprint of agriculture while maintaining commodity production. However, the performance of organic farming, often considered as a prototype of ecological intensification, in terms of pest control remains largely unknown. Here, using two distinct meta-analyses, we demonstrate that, compared to conventional cropping systems, (i) organic farming promotes overall biological pest control potential, (ii) organic farming has higher levels of overall pest infestations but (iii) that this effect strongly depends on the pest type. Our study shows that there are lower levels of pathogen infestation, similar levels of animal pest infestation and much higher levels of weed infestation in organic than in conventional systems. This study provides evidence that organic farming can enhance pest control and suggests that organic farming offers a way to reduce the use of synthetic pesticide for the management of animal pests and pathogens without increasing their levels of infestation.

Copper in plant protection: current situation and prospects

Abstract: Copper has been used in agriculture to control oomycetes, fungi and bacteria for over a century. It plays important roles in integrated pest management, but is essential in organic farming, where disease management depends almost exclusively on its use. However, the use of this heavy metal may have log-term consequences due to its accumulation in the soil, which appears incompatible with organic farming’s objectives. This awareness led the European Union to establish maximum limits on copper in organic farming since 2002 (Commission Regulation 473/2002), and further decisions on its use in crop protection are to be taken soon. At present, copper compounds are approved as plant protection products until 31 January 2019. This review examines the current state of copper use, the regulatory framework, and limits set for copper in organic farming. Strategies to reduce copper inputs are also considered, including: preventive phytosanitary measures, innovative formulations with reduced copper content, optimization of copper dosages, the use of forecasting models, the use of resistant varieties, optimization of agriculture management, and natural alternatives to copper-based products. This review also examines the main research projects exploring farming practices and appropriate alternatives to copper use for the control of plant pathogens. The review highlights that, while there is currently no replacement for this heavy metal having the same plant protection effectiveness, agronomic measures and management practices can be combined to reduce the amounts of copper used for this purpose.

Alternative Management Practices Improve Soil Health Indices in Intensive Vegetable Cropping Systems: A Review

Abstract: An increase in intensive cropping would benefit society by providing food to a growing population, and vegetable production is an excellent example of intensive cropping systems that are indeed on the rise. Vegetable cropping systems are high-input and generally require large quantities of fertilization, frequent irrigation, and repeated tillage operations. Consequently, an increase in global vegetable production may have seriously negative impacts on soil health and ecosystem services. Yet, not only maintaining but improving soil health is critical to enhancing the sustainability of food production systems. Previous agricultural research mainly focused on field crop systems and largely ignored vegetable cropping systems; consequently, this represents a conspicuous research gap, one that must be addressed in order to make progress towards sustainable food production. Here, we review the literature to gain a better understanding of how management has influenced various soil health indices (soil biology, chemistry, and physical dynamics) and to evaluate the implications for soil ecosystem services in vegetable cropping systems. We found that alternative modifications to conventional vegetable production systems, which resemble methods used in organic or conservation agriculture, tended to improve aspects of soil health. For example, soil amendments generally improved soil chemical indices of health – soil carbon levels and nitrogen reserves in particular. Incorporation of cover crops to vegetable crop rotations tended to improve nitrogen recycling via reduced nitrate leaching risks, increased soil carbon levels, and weed suppression. Reduced tillage systems were rare, presenting an important challenge and opportunity for further improving soil health dynamics in vegetable production. Notably, adopting alternative practices generally had no effect on crop yields, which implies little risk of yield penalties when agronomic management is carefully planned. Our results indicate that future sustainable vegetable cropping systems may embody a blend between organic and conventional ideologies to better maintain or improve soil ecosystem functioning.

Making conventional agriculture environmentally friendly: Moving beyond the glorification of organic agriculture and the demonization of conventional agriculture

Abstract: The article reviews the most recent research surrounding the potential role of organic agriculture in providing food for the planet. It challenges the claims of organic agriculture’s environmental superiority compared to well-managed, conventional agriculture. The relative advantages of these contrasting approaches to farming in areas such as aggregate land requirements, biodiversity/habitat loss, water quality, land degradation and climate change are considered. Legitimate concerns about conventional agriculture’s adverse environmental and health impacts need to be addressed and many harmful practices transformed. Nonetheless, careful, sustainably-run, conventional operations can avoid many of the pitfalls and hazards which are often associated with high-input agriculture. The higher yields provided by conventional agriculture offer a more sustainable strategy than a chemical-free agricultural system at the global level for meeting the needs of burgeoning populations and reducing agriculture’s aggregate environmental impact.

Organic substrate for transplant production in organic nurseries. A review

Abstract: A transplant can be defined as a seedling or sprouted vegetative propagation material grown in a substrate or in the field, for transfer to the final cropping site. Nurseries use a range of growing media in the production of transplants, and the quality of a substrate may be defined in terms of its feasibility for the intended use and also according to the climatic condition of the production site. Peat is the worldwide standard substrate, but because of its origin and the increasing environmental and ecological concerns, new alternatives have been proposed for organic production. Here, we reviewed these new alternatives, assuming that the proposed growing media will need to respond in a proper way to specific plant requirements while also taking them into consideration to be environmental friendly, at the same time. Appropriate composting management combined with suitable feedstock material can produce substrates with adequate properties to develop transplants. Potential added-value benefits of particularized compost have been highlighted, and these include suppressiveness or capacity for plant pathogen control, biofertilization, and biostimulation. This added value is an important point in relation to the framework of organic agriculture because the use of chemical fertilizers and pesticides is limited. Different permitted fertilizers are proposed by incorporating them by dress fertilization before planting or by foliar fertilization or fertigation during the seedling production phase. In this context, specific beneficial microorganism inoculation demonstrates better and quicker nutrient solubilization. Its inclusion during seedling production not only facilitates plant growth during the germination and seedling stages but also could bring efficient microorganisms or beneficial microorganisms to the field with the transplants. This review will help to bridge the gap between the producers of compost and the seedling plant producers by providing updated literature.

A Sustainable Agricultural Future Relies on the Transition to Organic Agroecological Pest Management

Abstract: The need to improve agricultural sustainability to secure yields, minimize environmental impacts and buffer environmental change is widely recognized. Investment in conventional agriculture has supported its present yield advantage. However, organic agriculture with agroecological management has nascent capacity for sustainable production and for increasing yields in the future. Conventional systems have leveraged reductionist approaches to address pests, primarily through pesticides that seek to eliminate biological factors that reduce yield, but come at a cost to human and ecosystem health, and leave production systems vulnerable to the development of pest resistance to these chemicals or traits. Alternatives are needed, and are found in organic production approaches. Although both organic and agroecology approaches encompass more than pest management, this aspect is a pivotal element of our agricultural future. Through increased investment and application of emerging analytical approaches to improve plant breeding for and management of these systems, yields and resilience will surpass approaches that address components alone.

Soil enzyme activities and abundance of microbial functional genes involved in nitrogen transformations in an organic farming system

Abstract: Organic farming systems receive organic amendments to maintain soil fertility and supply nutrients for plant growth. This study investigated the effect of organic fertilizers (no amendment as control, compost, and manure), and their interaction with cover crops (millet, buckwheat, and black turtle bean) on soil enzyme activities, N transformation rates, and functional gene abundances under an organic production system. Organic N fertilizers had a stronger effect than cover crop type on soil function and functional gene abundances. Soil enzyme activities were increased by both compost and manure, but there were few differences between these treatments. Nitrification potential, nitrite oxidation potential, and denitrification potential were significantly higher in manure-treated than in control and compost-treated soils, indicating application of manure had a higher N loss potential than compost application in this organic farming system. Organic N fertilizers significantly increased the abundance of some genes involved in N mineralization, ammonification, and nitrification (sub, ureC, bacterial amoA and nxrB). The activity of ammonia-oxidizing bacteria and archaea were both increased by organic N fertilizers, and their activities were higher in manure-treated than in compost-treated soils. Overall, the abundance of functional genes was significantly correlated with their corresponding enzyme activity. However, functional gene abundance was less important than soil chemical and microbiological properties in explaining the variation in the corresponding enzyme activity.

Phosphorus availability on many organically managed farms in Europe

Abstract: Maintaining sufficient soil phosphorus (P) levels for non-limiting crop growth is challenging in organic systems since off-farm inputs of P are restricted. This study assessed the status of P on organic farms in Europe using soil test results for extractable P. Data was obtained from published literature, unpublished theses, and various national and regional databases of soil test values. Most of the data (15,506 observations) came from field scale soil tests, but in some cases (1272 observations) values had been averaged across a farm. Farm scale and field scale data were analysed separately and the impact of farm type (arable, dairy, grassland, horticulture, mixed, poultry, unknown) was assessed. Soil test results were assigned to P classes from very low (P class 1) to very high (P class 5). The farm scale data came primarily from Norway, Sweden and Switzerland and did not indicate deficiencies in extractable P; 93% of farms fell into class 3 or above. The majority of the field scale data came from Germany and indicated sufficient or higher levels of P availability for arable and grassland systems on 60% of fields; the remaining fields had low or very low available P. Adaptations in organic systems may improve P uptake and utilization efficiency allowing yields to be maintained in the short-term, nevertheless there is cause for concern about the long-term P sustainability of some organic farming systems in Europe. This highlights the need to reassess allowable P inputs in organic farming systems to improve overall sustainability.

Soil fertility status and nutrient input–output flows of specialised organic cropping systems: a review

Abstract: The management of specialised organic crops for vegetable and fruit production require the use of imported fertilizers A wide range of fertilizers is currently available to organic farmers These include bulky organic materials with a relatively low nutrient concentration commonly used as base dressing (eg composts, solid animal manures) and complementary commercial organic fertilizers with relatively high nutrient concentrations to adjust nutrient supply to crop requirements (eg feather meal, hoof and horn meal, vinasse, meat and bone meal, etc) Nutrient imbalances are a major threat affecting the long term sustainability of horticultural and fruit cultivation systems Major reasons for these imbalances are the biased element composition of base as well as complementary fertilizers in relation to the nutrient offtakes via harvested products Gaseous nitrogen losses during manure management and gaseous as well as leaching nitrogen losses after application are major reasons for such nutrient imbalances, as they lead to a relative increase in the concentration of other elements Conceptual weaknesses in the fertilizer approach in organic farming exist, namely the preferred application of slow release nitrogen fertilizers often rich in phosphorus This review suggests that the current soil fertility approaches based on application of solid fertilizers and simultaneously a low rate of N inputs via N2 fixation do not foster balanced nutrient levels The key challenge is to design cropping systems with a higher share of N inputs via biological N2 fixation, and to find fertilizers with a nutrient stoichiometry better suited to match the overall specific offtakes of fertilized crops

Does organic farming present greater opportunities for employment and community development than conventional farming? A survey-based investigation in California and Washington

Abstract: Organic farming may present opportunities for job creation over and above those provided by conventional agriculture; this study is one of a small number to have empirically examined this propositi...

Ecosystem services and disservices provided by small rodents in arable fields: Effects of local and landscape management

Abstract: In agriculture, both valuable ecosystem services and unwanted ecosystem disservices can be produced by the same organism group. For example, small rodents can provide biological control through weed seed consumption but may also act as pests, causing crop damage. We studied the hypothesized causal relationships between ecosystem services (removal of weed seeds) and disservices (removal of wheat grains and crop damage) derived by small rodents (voles and mice) at multiple spatial scales. At the landscape scale, we studied the effects of landscape compositional and configurational heterogeneity on the abundance of voles and mice and their related ecosystem services and disservices along the former inner German border in east and west Germany. At the local scale, we studied how abundance and ecosystem functions are affected by management intensity (organic vs. conventional winter wheat), associated differences in crop characteristics and edge effects. Linear mixed-effects models and path analysis show that voles drove ecosystem disservices, but not ecosystem services, in agricultural fields. Daily wheat seed removal by voles was influenced by increasing wheat height and was almost three times higher than weed seed removal, which was not related to local- or landscape-scale effects. Abundance of voles and associated crop damage decreased with lower crop density and higher wheat height, which were associated with organic farming. Abundance of voles and crop damage were highest in conventional fields in west Germany. Synthesis and applications. As the ecosystem disservice of wheat seed consumption by small rodents must be considered mainly during crop sowing, management before crop harvest should focus on decreasing the pest potential of voles but not mice. Our results suggest that densities of voles and their ecosystem disservices could be reduced by having fields with low crop density and high wheat height, practices associated with organic farming. Surrounding landscapes with low compositional and configurational heterogeneity could further reduce voles’ pest potential, but with probable negative effects on farmland biodiversity.

Deployment of organic farming at a landscape scale maintains low pest infestation and high crop productivity levels in vineyards

Abstract: 1.Organic farming is a promising way to reduce pesticide use but increasing the area under organic farming at the landscape scale could increase pest infestations and reduce crop productivity. Examining the effects of organic farming at multiple spatial scales and in different landscape contexts on pest communities and crop productivity is a major step in the ecological intensification of agricultural systems. 2.We quantified the infestation levels of two pathogens and five arthropod pests, the intensity of pesticide use and crop productivity in 42 vineyards. Using a multiscale hierarchical design, we unraveled the relative effects of organic farming at both field and landscape scales from the effects of semi-natural habitats in the landscape. 3.At the field scale, pest communities did not differ between organic and conventional farming systems. At the landscape scale, increasing the area under organic farming did not increase pest infestation levels. 4.Three out of seven pest taxa were affected both by local farming systems and the proportion of semi-natural habitats in the landscape. Our findings revealed that the proportion of semi-natural habitats reduced pest infestation for two out of seven pest taxa, while the others were unaffected. 5.Organic vineyards had much lower treatment intensities, very similar levels of pest control and equal crop productivity levels. 6.Synthesis and Applications. Our results clearly indicate that policies promoting the development of organic farming in conventional vineyard landscapes will not lead to greater pest and disease infestations but will reduce the pesticide treatment intensity and maintain crop productivity. Moreover, the interactions between semi-natural habitats in landscape and local farming practices suggest that the deployment of organic farming should be adapted to landscape contexts. This article is protected by copyright. All rights reserved.