Research Papers
Assessing farmer interest in participatory plant breeding: Who wants to work with scientists?
- Julie C. Dawson, Jessica R. Goldberger
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- 30 June 2008, pp. 177-187
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Participatory research, particularly participatory plant breeding (PPB), can increase the relevance of public-sector research to the agricultural community. PPB has mostly been used in developing countries with resource-poor farmers, but there is increasing interest among farmers in developed countries who are dissatisfied with the performance of available varieties. In 2006, scientists associated with the winter and spring wheat breeding programs in the Department of Crop and Soil Sciences and the Department of Community and Rural Sociology at Washington State University (WSU) conducted a survey of members of the Washington Association of Wheat Growers. Through analysis of the survey results, we sought to understand (1) whether or not farmers want to work with scientists in PPB programs and (2) the determinants of PPB interest. Results indicated that 52% of Washington wheat growers were interested in working with WSU scientists in a participatory breeding program. Interested farmers tended to be younger and college educated with fewer years of farming experience. Moreover, PPB interest appeared to be related positively to farm size, the number of wheat varieties planted, use of and interest in alternative production and marketing practices (e.g., seed saving, organic agriculture), and prior experience with WSU. Based on this analysis and ongoing discussions with farmers, we hope to develop a participatory wheat breeding program where farmers are able to choose their level of involvement with the breeding process based on their interest and needs. This new program will increase the relevance of WSU's wheat breeding programs to farmers in the state and could serve as a model for other public agricultural research programs seeking to increase farmer involvement and, thereby, democratize agricultural research.
Preliminary Report
Introduction of floating gardening in the north-eastern wetlands of Bangladesh for nutritional security and sustainable livelihood
- Haseeb Md. Irfanullah, Ahana Adrika, Abdul Ghani, Zakir Ahmed Khan, Md. Abdur Rashid
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- 27 May 2008, pp. 89-96
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Floating gardening is a form of hydroponics or soil-less culture. It is an age-old practice of crop cultivation in the floodplains of southern Bangladesh, where aquatic plants such as water hyacinth (Eichhornia crassipes) are used to construct floating platforms on which seedlings are raised and vegetables and other crops cultivated in the rainy season. The platform residue is used in the preparation of beds for winter vegetable gardening. Floating gardening was introduced in 2006 on a pilot-scale in the north-east wetlands of the country, as a contribution to food security and as a supplementary income for the marginalized community. The overall experience of floating cultivation in three selected villages was encouraging. Local people became aware of this new farming system and their level of knowledge improved. Communities were mobilized into groups to make floating platforms, and platform residues were later used to establish winter gardens. Cultivation was successful on both types of plot, and vegetables were both consumed by the producers and sold in the market. The input–output analysis revealed floating gardening to be a feasible alternative livelihood option for the wetland dwellers. The method provided targeted landless people with parcels of land in the monsoon, enabling them to grow vegetables. Floating gardening and associated winter gardening appear to have the potential for introduction to other parts of the world where aquatic weed management is a major problem.
Editorial
Editorial: Exploring organic agriculture's place within the agricultural revolution
- Martin H. Entz, Daniel Neuhoff, William Lockeretz
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- 25 February 2008, pp. 1-2
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Principles of integrated agricultural systems
- Jon D. Hanson, Alan Franzluebbers
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- 31 October 2008, pp. 263-264
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Review Article
Benefits and barriers to perennial forage crops in Iowa corn and soybean rotations
- Julia Olmstead, E. Charles Brummer
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- 27 May 2008, pp. 97-107
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The transition away from forage-based cropping systems in Iowa to corn and soybean rotations since World War II has corresponded with degraded economic and environmental conditions in the state. Falling net incomes for farmers and concern over global warming and the effects of agriculture-related pollution on water, wildlife and human health have increased interest in diversified cropping systems. This paper reviews the benefits of diversifying Iowa corn and soybean rotations with perennial forage species such as alfalfa and red clover. Perennial forage crops improve soil quality, decrease NO3-N leaching and soil erosion, increase carbon sequestration and decrease pesticide and herbicide needs by controlling weed and insect pests. Forage legumes reduce N fertilizer needs for succeeding corn crops at a higher rate than soybeans, and corn crops following forages have higher yields than after corn or soybeans. Farmers who add alfalfa to corn and soybean rotations could realize significant economic gains. A simulated 5-year rotation in Iowa including corn–soybeans–oats/alfalfa–alfalfa–alfalfa would result in a 24% net income increase over 5 years of corn–soybean–corn–soybean–corn, even with government farm support payments for the row crops. Farm policies that encourage commodity production create little incentive for Iowa farmers to diversify their cropping systems beyond corn and soybeans, despite the clear economic and ecological benefits. We recommend increasing federal support for conservation programs that reward environmentally beneficial farm practices such as the Conservation Securities Program and we encourage land grant universities to hire researchers interested in alternative agricultural systems.
Research Papers
Grain legume–cereal intercropping: The practical application of diversity, competition and facilitation in arable and organic cropping systems
- Henrik Hauggaard-Nielsen, Bjarne Jørnsgaard, Julia Kinane, Erik Steen Jensen
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- 25 February 2008, pp. 3-12
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Intercropping is the simultaneous cultivation of more than one crop species on the same piece of land and is regarded as the practical application of basic ecological principles such as diversity, competition and facilitation. Field experiments were carried out on a sandy loam soil and a sandy soil in Denmark over three consecutive cropping seasons including dual grain legume (pea, faba bean and lupin)–barley intercropping as compared to the respective sole crops (SC). Yield stability of intercrops (IC) was not greater than that of grain legume SC, with the exception of the IC containing faba bean. Faba bean and lupin had lower yield stability than pea and fertilized barley. However, the different IC used environmental resources for plant growth up to 50% (LER=0.91–1.51) more effectively as compared to the respective SC, but with considerable variation over location, years and crops. The SC performance supported the interspecific interactions within the IC stand. On the sandy loam 13% greater grain yield of pea cv. Agadir (520 g m−2) was observed as compared to cv. Bohatyr. Faba bean and lupin yielded similarly (340 g m−2) in the sandy loam soil, with decreasing yields on the sandy soil (320–270 g m−2). Nitrogen fixation was very constant in grain legume SC over species and location, varying from 13.2 to 15.8 g N m−2, being lowest in peas and highest in faba bean and lupin. The intercropped grain legumes increased the proportion of plant N derived from N2-fixation by on average 10–15% compared to the corresponding SC. However, especially lupin was suppressed when intercropping, with a reduced N2-fixation from 15 to 5–6 g N m−2. The IC were particularly effective at suppressing weeds, capturing a greater share of available resources than SC. Weed infestation in the different crops was comparable; however, it tended to be the highest in sole cropped faba bean, lupin and unfertilized barley, where the application of urea to barley reduced the weed infestation by around 50%. Reduction in disease was observed in all IC systems compared to the corresponding SC, with a general disease reduction in the range of 20–40%. For one disease in particular (brown spot on lupin) disease reduction was almost 80% in the IC. Intercropping practices offer many advantages but improved understanding of the ecological mechanisms associated with planned spatial diversity, including additional benefits with associated diversity, is needed to enhance the benefits achieved.
‘I'm getting desperate’: what we know about farmers' markets that fail
- Garry Stephenson, Larry Lev, Linda Brewer
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- 30 June 2008, pp. 188-199
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This paper explores hidden problems amid the impressive expansion of farmers' markets in Oregon and throughout the United States. Although markets are growing in number, a surprisingly large number of them fail. A challenge for many markets is inadequate revenue to support market operations such as paying for the management personnel to perform functions necessary to grow and sustain markets. Smaller markets may enter a downward spiral in which they cannot attract additional customers because they do not have sufficient vendors but cannot attract additional vendors because they do not have sufficient customers. The analysis identifies five intertwined factors associated with markets that fail: small size, a high need for products, low administrative revenue, a volunteer or low paid manager and high manager turnover. The paper also examines the more general issue of why some markets struggle by exploring a correlation between new markets and inexperienced managers, and effort thresholds for volunteer managers. Recommendations to assist markets toward success include better planning, manager and board of director training and community financial support. The findings of this study have broad application.
Principles of integrated agricultural systems: Introduction to processes and definition
- John R. Hendrickson, J.D. Hanson, Donald L. Tanaka, Gretchen Sassenrath
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- 30 June 2008, pp. 265-271
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Agriculture has been very successful in addressing the food and fiber needs of today's world population. However, there are increasing concerns about the economic, environmental and social costs of this success. Integrated agricultural systems may provide a means to address these concerns while increasing sustainability. This paper reviews the potential for and challenges to integrated agricultural systems, evaluates different agricultural systems in a hierarchical systems framework, and provides definitions and examples for each of the systems. This paper also describes the concept of dynamic-integrated agricultural systems and calls for the development of principles to use in developing and researching integrated agricultural systems. The concepts in this paper have arisen from the first in a series of planned workshops to organize common principles, criteria and indicators across physiographic regions in integrated agricultural systems. Integrated agricultural systems have multiple enterprises that interact in space and time, resulting in a synergistic resource transfer among enterprises. Dynamic-integrated agricultural systems have multiple enterprises managed in a dynamic manner. The key difference between dynamic-integrated agricultural systems and integrated agricultural systems is in management philosophy. In an integrated agricultural system, management decisions, such as type and amount of commodities to produce, are predetermined. In a dynamic-integrated system, decisions are made at the most opportune time using the best available knowledge. We developed a hierarchical scheme for agricultural systems ranging from basic agricultural production systems, which are the simplest system with no resource flow between enterprises, to dynamic-integrated agricultural systems. As agricultural systems move up in the hierarchy, their complexity, amount of management needed, and sustainability also increases. A key aspect of sustainability is the ability to adapt to future challenges. We argue that sustainable systems need built-in flexibility to achieve this goal.
Strategies to control Canada thistle (Cirsium arvense) under organic farming conditions
- Pavel Lukashyk, Martin Berg, Ulrich Köpke
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- 25 February 2008, pp. 13-18
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Three strategies for controlling Cirsium arvense including (i) repeated stubble tillage with subsequent forage crop cultivation, (ii) repeated mowing of a ryegrass–clover ley and (iii) forage crop cultivation following a ryegrass–clover ley ploughed in May/June were investigated in field experiments over 3 years at the Experimental Farm for Organic Agriculture ‘Wiesengut’ in North-Rhine Westphalia, Germany. The development of C. arvense (shoot density, shoot size and ground cover) was regularly assessed on fixed standardized subplots. In the medium-term (9 months), repeated stubble tillage (i) decreased shoot density and regrowth capacity of C. arvense more effectively than a mowed ryegrass–clover ley (ii and iii). However, after 22 months, strategies (i) and (ii) resulted in a similar strong reduction of C. arvense shoot density of 95 and 97%, respectively. At this time, the efficacy of strategy (iii) (89%) was not significantly different to that of strategies (i) and (ii). After 26 months, the effect of all strategies was still apparent; however, the efficacy of strategy (iii) was significantly lower than that of strategy (ii). Generally, the different strategies showed only minor differences, thus delivering options for optimal strategies of thistle control under given specific conditions of sites and cropping systems.
Adding value in the organic sector: Characteristics of organic producer–handlers
- Lydia Oberholtzer, Carolyn Dimitri, Catherine Greene
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- 04 July 2008, pp. 200-207
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Sales of organic food have soared over the past decade. Although nearly all organic commodities pass through the hands of at least one intermediary on the way from the farmer to the consumer, there is a dearth of literature examining organic food marketing, especially for the middle section of the supply chain. This paper uses new survey data on organic intermediaries (organic handlers) to characterize firms that are certified to both handle and produce organic foods, or organic producer–handlers. Because of their direct link to the production level, the producer–handler has the potential to provide insight into value-added activities in the organic sector. A logistic regression is estimated in order to identify characteristics that make it more likely that a firm would be both a certified organic handler and a certified organic producer, while survey results are also used to describe some of the main challenges these producer–handlers face in handling their products. Organic producer–handlers ranked problems with ingredient procurement and supply and international trade issues as the highest barriers to growth. The model indicated that with few exceptions, many of the operational and procurement characteristics of organic producer–handlers are comparable to the entire organic handling population. However, those facilities dedicated solely to organic handling and those certified longer are more likely to be organic producer–handlers. Use of direct markets by organic handlers has the most robust relationship in the model, although marketing to natural products independent retailers and wholesalers are also important.
Effects of soil fungi on weed communities in a corn–soybean rotation
- N. Jordan, S. Huerd
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- 27 May 2008, pp. 108-117
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In a variety of ecosystems, interactions between soil microbiota and weedy plants can strongly affect population and community dynamics of these plants. However, weed–soil microbe interactions are not well characterized in field-crop agroecosystems. In Minnesota (USA), we repeatedly applied a fungicide (benomyl) to field plots in a corn–soybean crop rotation in each of 3 years, and sowed experimental weed communities containing host species for arbuscular-mycorrhizal fungi (AMF) and non-host species. Benomyl typically suppresses formation of mycorrhizal symbiosis in AMF-host plant species, and may also affect other soil fungi. We assessed weed density and biomass production, and monitored AMF colonization rates in each of 3 years. We found that weed density, biomass, community composition and the relative performance of AMF-host and non-host weed species were all significantly responsive to fungicide applications, although for all attributes responsiveness was variable. Fungicide application increased total weed density and biomass production in nearly all cases; most effects were modest but reached a maximum of 49%. Fungicide application also increased the relative performance of non-host species in most cases, although most effects were again modest. Our findings are the first assessment of responses by field-crop weeds to direct manipulation of soil microbial communities in a field setting, and suggest that the population and community ecology of these weeds can be strongly affected by the fungal component of soil microbiota.
Social and political influences on agricultural systems
- David W. Archer, Julie Dawson, Urs P. Kreuter, Mary Hendrickson, John M. Halloran
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- 30 June 2008, pp. 272-284
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Agricultural systems are situated within social and political environments that have tremendous influence on how they operate. If agricultural systems are to be sustainable, it is critical to understand how they are influenced by social and political factors. An expert panel approach was used to identify and rank the importance of social and political factors on agricultural systems in the US and to provide some insights into their impacts, interactions and mechanisms of influence. The panel identified a wide range of social and political factors that affect agricultural systems. The factors were divided into three categories: internal social factors, external social factors and political factors. Factors from each of the three categories were highly ranked, indicating that no single category dominated the others. Although there were contrasting views about the importance of some factors, there was strong consensus about many of them. Globalization and low margins that require increased scale and efficiency were identified as the two most important factors affecting agricultural systems. Several newly emerging factors were identified as well as factors needing further research. A comprehensive understanding of these factors is imperative to help guide scientific research so that beneficial discoveries are accepted and used, and to ensure that policy decisions enhance the future sustainability of agricultural production.
Addendum
Effects of soil fungi on weed communities in a corn–soybean rotation – ADDENDUM
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- 27 May 2008, pp. 118-119
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Review Article
Technology, complexity and change in agricultural production systems
- G.F. Sassenrath, P. Heilman, E. Luschei, G.L. Bennett, G. Fitzgerald, P. Klesius, W. Tracy, J.R. Williford, P.V. Zimba
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- 04 July 2008, pp. 285-295
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Technological advances have contributed to impressive yield gains and have greatly altered US agriculture. Selective breeding and directed molecular techniques address biological shortcomings of plants and animals and overcome environmental limitations. Improvements in mechanization, particularly of power sources and harvest equipment, reduce labor requirements and increase productivity and worker safety. Conservation systems, often designed to overcome problems introduced from other technologies, reduce negative impacts on soil and water and improve the environmental sustainability of production systems. Advances in information systems, largely developed in other disciplines and adapted to agriculture, are only beginning to impact US production practices. This paper is the fourth in the series of manuscripts exploring drivers of US agricultural systems. While development of technology is still largely driven by a need to address a problem, adoption is closely linked with other drivers of agricultural systems, most notably social, political and economic. Here, we explore the processes of innovation and adoption of technologies and how they have shaped agriculture. Technologies have increased yield and net output, and have also resulted in decreased control by producers, increased intensification, specialization and complexity of production, greater dependence on non-renewable resources, increased production inputs and hence decreased return, and an enhanced reliance on future technology. Future technologies will need to address emerging issues in land use, decline in work force and societal support of farming, global competition, changing social values in both taste and convenience of food, and increasing concerns for food safety and the environment. The challenge for farmers and researchers is to address these issues and develop technologies that balance the needs of producers with the expectations of society and create economically and environmentally sustainable production systems.
Research Papers
Organic premiums of US fresh produce
- Biing-Hwan Lin, Travis A. Smith, Chung L. Huang
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- 30 June 2008, pp. 208-216
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The study uses the 2005 Nielsen Homescan panel data to estimate price premiums and discounts associated with product attributes, market factors, and consumer characteristics, focusing on the organic attribute for five major fresh fruits and five major fresh vegetables in the United States. The results suggest that the organic attribute commands a significant price premium, which varies greatly from 13 cents per pound for bananas to 86 cents per pound for strawberries among fresh fruits and from 13 cents per pound for onions to 50 cents per pound for peppers among fresh vegetables. In terms of percentages, the estimated organic price premiums vary from 20% above prices paid for conventional grapes to 42% for strawberries among fresh fruits and from 15% above prices paid for conventional carrots and tomatoes to 60% for potatoes. Furthermore, prices paid for fresh produce are found to vary by other product attributes, market factors, and household characteristics.
Tanniferous forage plants: Agronomic performance, palatability and efficacy against parasitic nematodes in sheep
- D.A. Häring, A. Scharenberg, F. Heckendorn, F. Dohme, A. Lüscher, V. Maurer, D. Suter, H. Hertzberg
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- 25 February 2008, pp. 19-29
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Tanniferous forage plants can have beneficial effects on ruminant productivity and health (improved protein supply, bloat safety and antiparasitic properties). However, condensed tannins can also lower palatability, voluntary feed intake and digestibility. The aim of our interdisciplinary project was to generate basic knowledge on plant management, feed palatability and the antiparasitic properties of tanniferous forage plants for their practical application in agronomy, focusing on their usefulness in controlling gastrointestinal nematodes in organic farming. We found that Onobrychis viciifolia (sainfoin), Lotus corniculatus (birdsfoot trefoil) and Cichorium intybus (chicory) were suitable for cultivation under the given temperate climatic conditions, whereas Lotus pedunculatus (big trefoil) was soon outcompeted by unsown species. Growing the tanniferous plant species in a mixture with Festuca pratensis (meadow fescue) rather than in a monoculture had the advantage of increasing total dry matter (DM) yield (especially in the case of tanniferous legumes) and of reducing the DM proportions of unsown species. However, due to dilution by non-tanniferous F. pratensis, the tannin concentrations of mixtures were clearly lower and the seasonal fluctuations in tannin concentrations greater than that of monocultures. Across species, tannin concentrations were highest for O. viciifolia, followed by L. corniculatus and very low for C. intybus. Palatability of all tanniferous forages was comparable to that of a ryegrass/clover mixture when fed as dried forage and, when offered as silage, palatability of O. viciifolia was clearly superior to that of the respective ryegrass/clover control. Administration of dried or ensiled O. viciifolia reduced parasite egg counts in feces of lambs co-infected with the gastrointestinal nematode species Haemonchus contortus and Cooperia curticei. We conclude that O. viciifolia is the most promising among the tested tanniferous forage plant species due to its suitability for cultivation, its high tannin concentration, its high palatability and its antiparasitic activity even in dried or ensiled form.
Review Article
External economic drivers and US agricultural production systems
- J.M. Halloran, D.W. Archer
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- 30 June 2008, pp. 296-303
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US agriculture operates in a market driven economy, although government policies can have influence on what farmers produce and how they produce it. As with other businesses, agricultural producers respond to economic incentives and disincentives, and make decisions to maximize their welfare; usually measured as net income. We examined how external economic drivers shape the type of agricultural systems that producers adopt. Specifically, we considered the influence of technological advancements, income supports embodied in farm legislation, and changes in market structure and consumer demand. Changes in technology have often favored large-scale and specialized operations. Many of the technological advancements have required large-scale production units to justify the investment. Often the technology has been commodity specific. However, there is some evidence that more diversified production units might be able to achieve economies of both scale and scope. The influence of commodity support programs has been ambiguous. As farm legislation has evolved to decouple production decisions from program benefits, the incentives to specialize in program crops (crops that receive price and/or income benefits under federal legislation, such as corn, other grains and oil seeds) have diminished. However, wealth and risk effects, albeit small, may have promoted or inhibited the adoption of a more integrated system. The ability of producers to adopt more integrated systems has been primarily influenced by their natural resource base and proximity to markets. Changes in market structure, channels and consumer demand in the past five decades have been dramatic with consolidation and specialization in both production and marketing sectors. However, the diversity of consumer demand has also created opportunities for more integrated farm operations. There is an increasing number of consumers who have become concerned about how and where their food has been produced. Markets for organic, locally produced, free range and the like are expected to grow. While price and income supports may have been biased towards specialization (as these programs were targeted to specific commodities), the reduction in risk associated with the programs has enabled producers to expand the number and diversity of their production enterprises. Furthermore, through the use of strategic alliances, cooperation among producers on a regional basis may eventually lead to greater integration and diversification than could be achieved for the individual farm operation.
Research Papers
Energy self-reliance, net-energy production and GHG emissions in Danish organic cash crop farms
- N. Halberg, R. Dalgaard, J.E. Olesen, T. Dalgaard
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- 25 February 2008, pp. 30-37
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Organic farming (OF) principles include the idea of reducing dependence of fossil fuels, but little has been achieved on this objective so far in Danish OF. Energy use and greenhouse gas (GHG) emissions from an average 39 ha cash crop farm were calculated and alternative crop rotations for bio-energy production were modeled. Growing rapeseed on 10% of the land could produce bio-diesel to replace 50–60% of the tractor diesel used on the farm. Increasing grass-clover area to 20% of the land and using half of this yield for biogas production could change the cash crop farm to a net energy producer, and reduce GHG emissions while reducing the overall output of products only marginally. Increasing grass-clover area would improve the nutrient management on the farm and eliminate dependence on conventional pig slurry if the biogas residues were returned to cash crop fields.
Economics of organic and conventional hazelnut production in the Terme district of Samsun, Turkey
- Kursat Demiryurek, Vedat Ceyhan
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- 30 June 2008, pp. 217-227
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Understanding the economics of organic agriculture is crucial to support of organic production by policy-makers and to facilitate producers converting their lands to organic production. The aim of this research was to compare organic and conventional hazelnut producers, in terms of their socio-economic characteristics, production systems and economic performance. The main data were gathered with surveys of 64 randomly selected conventional hazelnut producers and all the organic hazelnut producers (39) living in villages of the Terme district of Samsun, Turkey in 2005. Results revealed that, compared to conventional hazelnut producers, organic hazelnut producers were more educated, had larger hazelnut areas and spent more time on agricultural activities. The current research also used cluster analysis to define relatively similar farmers from both production systems and to compare variables. Organic producers needed more labor, especially hired workers, and used more lime, organic fertilizer and insect traps, while conventional producers used more synthetic inputs. Organic producers had lower costs of production and had higher income. It is recommended that the organic producers be supported financially, and assisted by research and extension services to produce and use their own inputs, rather than purchasing from outside. They should also be encouraged to establish associations to increase their marketing efficiency.
Weed management in organic echinacea (Echinacea purpurea) and lettuce (Lactuca sativa) production
- P. Kristiansen, B.M. Sindel, R.S. Jessop
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- 27 May 2008, pp. 120-135
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Weed management is a major constraint in organic production. It can be expensive and time-consuming and severe crop yield losses may be incurred when weeds are not adequately controlled. Research on organic weed management (OWM) in herb and vegetable production is increasing internationally, although in Australia very little work has been done to assess current OWM knowledge among growers, and to test the efficacy and cost effectiveness of the weed management practices used by organic growers. The effect of hand weeding, tillage, hay mulch, pelletized paper mulch (PP) and an unweeded control treatment on weed growth, crop growth and cost effectiveness were evaluated in several field trials on the Northern Tablelands of New South Wales using lettuce (Lactuca sativa L.) and echinacea (Echinacea purpurea Moench. [L.]). In echinacea, hand weeding, hay mulch and PP reduced weed growth by at least 90% compared with the control, while tillage reduced weed levels by about 50%. The more expensive weeding methods such as hand weeding and hay mulch (AU$9600 and 8900 ha−1 respectively) produced higher yields, while the cheaper methods such as tillage ($4000 ha−1) had low crop yields and were therefore 25–50% less cost effective. In lettuce, weed growth was reduced by 96% for hand weeding and PP compared with the control, 85% for hay mulch and 66% for tillage. Weed management was cost-effectively achieved using cheaper weeding methods such as tillage ($985 ha−1) compared with more expensive methods such as hand weeding and hay mulching ($4400 and 7600 ha−1 respectively). PP had lower yields and was expensive ($12,500 ha−1) and was usually not cost effective in these trials. The results highlight several important advantages and disadvantages of currently used OWM methods in the field.