Research Article
Phytotoxicity factors and herbicide contamination in relation to compost quality management practices
- T.Craig Blewett, David W. Roberts, William F. Brinton
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- 12 February 2007, pp. 67-72
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The practice of composting mixed green wastes from community collection programs has been on the increase as a means to reduce organic debris to landfills. Recent reports of plant injury have appeared and were attributed to residues of the herbicide clopyralid in compost. Phytotoxicity issues with compost have been reported previously to result from other factors, including heavy metal content, soluble salts, organic acids and oxygen deprivation related to incomplete decomposition. The recent reports of plant injury due to clopyralid-contaminated compost were also associated with very heavy applications of compost, yet few of these reports included observations of herbicide symptomology. Since immature compost may contain sufficient degradation intermediates, soluble salts and other contaminants to cause phytotoxicity, particularly when applied at heavy rates, an effort must be made to distinguish confounding factors. Complete composting normally allows for the degradation of phytotoxic intermediates and synthetic compounds, such as herbicides, as well as allowing for leaching of salts. Absence of compost completeness standards within the compost industry leaves such factors to the guesswork of the end-user. Recommended compost use rates have established a relationship between compost maturity, application rate and use pattern, based on compost quality metrics. Greater attention to the use of high-quality compost, properly designated as to completeness of composting and applied at appropriate use rates, would minimize the potential for phytotoxic effects, irrespective of the contributing source.
Comparison of consumer perceptions and preference toward organic versus conventionally produced foods: A review and update of the literature
- Emmanuel K. Yiridoe, Samuel Bonti-Ankomah, Ralph C. Martin
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- 12 February 2007, pp. 193-205
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Growing interest in organic agriculture has prompted numerous studies that compare various aspects of organic and conventionally produced foods. This paper provides a comprehensive evaluation of empirical studies comparing organic products and conventionally grown alternatives. The emphasis is on key organic consumer demand and marketing issues, including: (1) the implications of an economic definition of organically grown food for consumer demand; (2) attributes that shoppers consider most when comparing organic with conventionally grown products; (3) level and characteristics of consumer knowledge and awareness about organic food; (4) assessment methods and characteristics of organic consumer attitudes and preferences; (5) size of price premium and characteristics of consumers’ willingness-to-pay for organic products; and (6) profile of organic consumers. Overall, although there is some knowledge and awareness about organic products, consumers are not consistent in their interpretation of what is organic. Secondly, while consumers typically understand the broad issues about organic foods, many tend not to understand the complexities and niceties of organic farming practices and organic food quality attributes. Uncertainty regarding the true attributes of organic, and skepticism about organic labels, part of which stems from reported cases of (inadvertent) mislabeling, and product misrepresentation, and partly because of nonuniform organic standards and certification procedures, may hold some consumers back from purchasing organic. Thirdly, concern for human health and safety, which is a key factor that influences consumer preference for organic food, is consistent with observed deterioration in human health over time and, therefore, motivates consumers to buy organic food as insurance and/or investment in health. Fourthly, the proportion of consumers who are willing to pay a price premium for organic food decreases with premium level. On the other hand, premiums tend to increase with (combinations of) preferred attributes. In addition, demand tends to depend more on the price differential with respect to conventionally grown products, than on actual price. In contrast to sensitivity of demand to changes in price, income elasticity of demand for organic foods is generally small. Finally, it is important for policy analysts and researchers to note that organic fresh fruits and vegetables currently dominate the organic consumer's food basket. Furthermore, it is not clear whether frequent buyers consider particular organic products (e.g., organic meat) as normal goods, or if consumers consider such products as luxury goods.
The necessity and possibility of perennial grain production systems
- Jerry D. Glover
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- 12 February 2007, pp. 1-4
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Improved manure management and utilization: A systems approach
- Laura McCann, Charles Abdalla, Mark Jenner, Ray Massey
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- 12 February 2007, pp. 127-135
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The manure issue is complex and inherently interdisciplinary but, more fundamentally, it requires systems thinking. Current policies, technologies, infrastructure, incentives and modes of thinking about the problem fail to consider the system-wide implications, and thus fail to foster the creation of new and innovative solutions. At the farm level, complexity, uncertainty and lack of compatibility with the current farming system need to be addressed in order to promote better manure management. Production facilities, feed management and waste treatment systems (including centralized treatment plants) need to be designed to allow for beneficial use of manure components. At the industry level, changes in the poultry, swine and beef industries have resulted in concentration, both in terms of decision-making and geography. This currently limits the ability of these farmers to take a systems approach to livestock production. Environmental policies thus need to take account and advantage of this new reality. At the economy-wide level, factors affecting the demand and supply for alternative manure products need to be considered. A number of innovative uses are being developed in the private sector, but there are constraints as far as technology, institutions and infrastructure are concerned. A systems perspective will allow the design of policies and technologies that reduce environmental problems associated with manure, while promoting efficient utilization of the resource.
Perennial grain crops: A synthesis of ecology and plant breeding
- L.R. DeHaan, D.L. Van Tassel, T.S. Cox
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- 12 February 2007, pp. 5-14
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Perennial grain crops would address many agricultural problems, including soil erosion, nutrient loss and pesticide contamination. Doubts about the possibility of perennial grain crops rest upon two assumptions: (1) that the relationship between yield and longevity is a fixed function that cannot be influenced by selection, mutation or environmental changes; and (2) that yield and longevity trade off in a bivariate manner to the exclusion of all other traits. These assumptions are consistent with the phenotypic trade-off model, but recent research suggests that a quantitative genetic model is a more appropriate approach to trade-offs. In the quantitative genetic model, environmental and genetic changes can result in increases in two traits simultaneously even when a trade-off, or negative correlation, exists between the two traits. Empirical evidence that the trade-off between perenniality and reproductive allocation is not fixed comes from wild, herbaceous perennials that can produce more than 2000 kg seed ha−1 in the temperate zone, and herbaceous perennial crops that produce on average 8900 kg fruit ha−1 in the tropics. Ecological literature suggests that most perennials produce small amounts of seed relative to their vegetative growth not as a physiological absolute, but rather as a result of natural selection in a stable, competitive environment favoring longevity. By selecting strongly for seed yield in a population of perennial plants, the plant breeder can likely achieve that which is rare in nature—a high seed-yielding perennial plant. The same general methodologies that have allowed annual grain breeders to increase grain yield and push many combinations of negatively correlated traits to levels of expression not seen in nature are available to the perennial grain breeder. Perennial grain breeders are integrating ecological principles and traditional plant breeding methods in their efforts to develop perennial grain wheat (Triticum spp.), sorghum (Sorghum spp.), sunflower (Helianthus spp.), Illinois bundleflower (Desmanthus illinoensis) and rice (Oryza spp.).
Organic cucumber production in the greenhouse: A case study from Turkey
- Y. Tuzel, A. Gul, O. Tuncay, D. Anac, N. Madanlar, Z. Yoldas, M. Gumus, I.H. Tuzel, S. Engindeniz
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- 12 February 2007, pp. 206-213
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Organic farming seems to be a solution in environmentally sensitive zones such as the protection zone of Tahtalı Dam, which supplies fresh water to Izmir, the third largest city in Turkey. Greenhouse vegetable production is the major agricultural activity in this area (Menderes Township). However, due to the pollution risk from agriculture, governmental authorities have issued a regulation discouraging the use of chemicals within the collection basin of the dam. An on-farm project was conducted in 2001 to introduce organic greenhouse vegetable production in the Tahtalı Dam preservation area and to serve as a model for other areas in Turkey facing similar ecological problems. Two irrigation levels and four organic fertilizers were tested on the growth of cucumbers (Cucumis sativus cv. Sardes). The four fertilizers were two rates of farmyard and poultry manure (30 and 50 tons ha−1) with and without two organic fertilizers based on either bacteria or algae. During the growing period, pests and diseases were monitored weekly and preparations allowed in organic agriculture were used when necessary. Plant diseases did not create any significant problem, but the pest population, in particular spidermites, increased. No significant differences in cucumber yield were found between the fertilizer and irrigation treatments tested. However, it should be noted that yields from the addition of 30 tons ha−1 of farmyard or poultry manure and organic fertilizers were the same as those for 50 tons ha−1 of manure alone. The average total yield was 13 kg m−2, within an acceptable range for short-term crop production in this region, but 55% lower than a conventional substrate culture trial nearby. However, due to reduced production costs and a price premium for organic products, the organic produce yielded a net return of US$1.12–1.79 per m2 whereas that for conventional bag culture produce was US$0.55 per m2. Our results indicate that, under present conditions, organic greenhouse cucumber production has less environmental impact and is more economic than conventional bag culture, due to reduced chemical input and reduced operating and initial investment costs.
The use of human waste for peri-urban agriculture in Northern Ghana
- O.O. Cofie, G. Kranjac-Berisavljevic, Pay Drechsel
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- 12 February 2007, pp. 73-80
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In Ghana, studies on the use of organic materials to increase soil productivity have focused on crop-residue management, use of green and animal manures, and legume cover cropping. Few studies have assessed the use of human waste for agriculture, even though this is widely practiced by farmers in the northern part of the country. This study was carried out to investigate the stakeholders in the use of faecal sludge (FS) for crop production in Tamale and Bolgatanga municipalities in the guinea savanna agroecological zone of Ghana. The aim was to determine the driving factors, constraints and potentials for this practice. Field survey and focus group discussions were carried out among 90 farmers who use FS, and officials of the Municipal Sanitation Unit were interviewed. Sixty-four percent of farmers interviewed used FS as a cost-effective way to improve soil fertility and increase yields of maize and sorghum. Sludge is discharged by spreading it on the soil surface, or it is stored and dried in pits during the dry season and incorporated into the soil at the onset of the rainy season. The high temperatures of the savanna climate and this long period of drying allow sludge to be handled easily. Although this treatment is perceived to reduce the number of pathogens in dried sludge, 22% of farmers complained of itching feet and foot rot after working with FS, which is done without wearing protective foot covering. This constraint is coupled with the foul smell, transport problem and public mockery associated with the use of human waste for agriculture. In spite of these problems, there is competition for FS among farmers, due to benefits derived from its use. Further investigation is required to ascertain the causes of itching feet and foot rot, and there is a need for education on proper handling and appropriate hygiene practices when working with FS. Information regarding optimal FS application rates is also required.
Priority setting in agricultural land-use types for sustainable development
- Nevin Akpinar, Ilkden Talay, Sema Gun
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- 12 February 2007, pp. 136-147
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Even in developing countries that are faced with ecological and socio-economic problems, agricultural areas are constrained by land-use laws to be developed in particular ways. This being the case, the major issues in these areas are a better quality of life and sustainable use of the limited resources. This necessitates planning for sustainable development and evaluating various qualitative and quantitative data in a single framework. Multicriteria or multipurpose decision analysis methods are appropriate for this purpose. Using these methods, physical, economical and social data, as well as planning goals, can be combined and evaluated in the context of sustainable development. These multicriteria methods have been documented widely in a variety of problem areas, but two multicriteria methods, namely AHP (analytic hierarchy process) and ELECTRE II (elimination and choice translating reality), have not been used extensively in agricultural land-use decisions in developing countries. However, in situations where decision-making criteria are non-commensurable, non-comparable or non-countable, and when it is necessary to evaluate the criteria together, as in agricultural land-use decisions, AHP and ELECTRE II methods are warranted. This study reviews these methods briefly and suggests their potential application in the agricultural land-use decision process in a developing country. For this purpose, these methods were sampled in Ziyaret Stream Basin in Adiyaman, which is part of the Güneydoğu Anadolu Projesi (GAP) (South-eastern Anatolian Project) in the Republic of Turkey. The area could be characterized by its rural and agricultural features, although it is under the pressure of Adiyaman urban development. This study shows that both AHP and ELECTRE II methods can be applied successfully for the determination of agricultural land-use priorities, which are an essential part of the quality of life and of sustainable land-use studies.
Comparing agroecosystems: Effects of cropping and tillage patterns on soil, water, energy use and productivity
- Megan M. Gregory, Kathleen L. Shea, Eugene B. Bakko
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- 12 February 2007, pp. 81-90
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We compared soil characteristics, runoff water quantity and nutrient fluxes, energy use and productivity of three farm types in an unusually dry farming season: conventional (continuous corn and deep tillage), rotation (5-year corn–soybean–oats/alfalfa–alfalfa–alfalfa rotation with tillage 2/5 years) and no-till (corn–soybean with no cultivation). Soil organic matter content was highest on the rotation farm, followed by the no-till farm, and lowest on the conventional farm. Nitrate content of the soil did not differ significantly among the three farms, although the conventional farm had a much higher input of fertilizer nitrogen. Soil penetrometer resistance was lower and percent soil moisture was higher in the no-till and rotation systems compared to the conventional farm. Soil macroinvertebrate abundance and diversity were highest on the no-till farm, followed by the rotation farm. No invertebrates were found in the soil of the conventional farm. The conventional farm had the highest runoff volume per cm rain and higher nitrogen (N) loss in runoff when compared to the rotation and no-till farms, as well as a higher phosphorus (P) flux in comparison to the no-till farm. These results indicate that perennial close-seeded crops (such as alfalfa) used in crop rotations, as well as plant residue left on the surface of no-till fields, can enhance soil organic content and decrease runoff. The lower soil penetrometer resistance and higher soil moisture on the rotation and no-till farms show that conservation tillage can increase soil aggregation and water infiltration, both of which prevent erosion. Furthermore, crop rotation, and particularly no-till, promote diverse invertebrate populations, which play an important role in maintaining nutrient cycling and soil structure. Crop rotation and no-till agriculture are less fossil-fuel intensive than conventional agriculture, due to decreased use of fertilizers, pesticides and fuel. In this unusually dry year they provided superior corn and soybean yields, most likely due to higher soil moisture as a result of greater water infiltration and retention associated with cover crops (rotation farm) and crop residue (no-till farm).
Proposal for a more efficient subsidy system for organic farming: Potential use of the tax system within the European Union
- Enno Bahrs
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- 12 February 2007, pp. 148-154
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Agricultural enterprises that are run on ecological principles receive, in some countries, higher levels of financial support from the European Union (EU) than other agricultural businesses. The aim is to provide an incentive for businesses to adopt organic farming systems, a change desired by both politicians and society. However, with a fixed system of support payments based on land area, increasing the proportion of farms being run organically leads directly to higher costs of subsidies for the EU and the individual countries. This becomes especially true if enterprises with large land areas, high turnover and high income are converted to organic farming methods. Because financial resources within the member states are in very short supply, a modification of the current system of subsidies would seem to be necessary in the near future. The aim of any new system should be to reduce profit windfalls without making a drastic reduction in the incentive effect of the current system. At the same time, businesses that can run along these lines on a sustainable basis should be especially supported. This requires an increased level of individual assessment of the potential of the subsidized enterprises in relation to their cost–performance ratio for organic agricultural production. In this connection, a partial change to profit-based tax systems can be used as an effective instrument for co-financing. The method used to calculate profits for tax purposes, which varies from state to state, can be used to assess the performance and success of the organic farmer. Tax-free allowances or reductions in tax rates could be used to provide a selective subsidy method. The ability to relate subsidies to performance, thereby reducing windfall profits, is not the only advantage of using the tax system for this purpose. Another advantage is the low transaction costs. Using the example of the offsetting of profits between time periods, it will be shown here that the tax system can be used as an additional instrument for subsidization. The existing methods of subsidy can only be supported in this way, not completely substituted.
Substrates and fertilization for the rustic cultivation of in vitro propagated native orchids in Soconusco, Chiapas
- Anne Damon, Marco Pérez Soriano, Maria Rivera del Lourdes
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- 12 February 2007, pp. 214-222
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Native orchid cultivation is a compatible alternative for impoverished coffee farmers in southeastern Mexico who are in crisis due to falling prices. Sustainable orchid cultivation is also an urgent necessity as an alternative to nonsustainable extraction from protected reserves, forest fragments and traditional coffee plantations, and to restore and conserve populations within these habitats. Our objective was to test the effects of locally available substrates and fertilizers upon orchids cultivated under typical rural conditions in coffee-producing areas in Soconusco, Chiapas. Seven species of epiphytic orchids native to Soconusco region—Cattleya aurantiaca, Brassavola nodosa, Prosthechea (Encyclia) chacaoensis, Anathallis (Pleurothallis) racemiflora, Cattleya skinneri, Cycnoches ventricosum and Encyclia cordigera—were propagated in vitro, acclimatized and established in rustic orchid galleries in the home gardens and plantations of coffee growers. Locally available waste products were used as substrates: clay tiles, tree bark, bamboo, seed hulls of pataxte (Theobroma bicolor) and wire baskets filled with bark chips. Two cheap and readily available commercial foliar feeds, Algaenzims (an organic product) and Bayfolan (a synthetic product) were tested. First, the substrates alone were tested for a period of 6 months to 1 year, then a combination of substrates and fertilizers were tested for 6 months, for effects upon leaf and root growth and root number. The mortality rates of these nonsymbiotically propagated, epiphytic orchids during the acclimatization phase, prior to these experiments, were high, between 60 and 90%. Once established in rustic galleries, the young orchid plants showed no preference for a particular substrate, survival depended upon technical problems during establishment, relating to difficulties with the attachment of plants to substrates, and the variable quality of care and attention offered by the farmers. Both fertilizers significantly improved one or all the parameters studied, and possibly counteracted the negative effects of the absence of symbiotic fungi, which, under natural conditions, are essential for orchid seed germination and adequate development of the young plant. More than half of the producers did not continue with the orchid cultures for economic and cultural reasons.
Meeting the challenge of disease management in perennial grain cropping systems
- C.M. Cox, K.A. Garrett, W.W. Bockus
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- 12 February 2007, pp. 15-24
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Perennial grain production will likely present unique challenges for managing diseases that affect the productivity and longevity of crops being considered. Typical cultural practices effective at reducing soil- and residue-borne pathogens, such as annual crop rotations, delayed fall planting, and tillage, are not feasible in perennial systems. Consequently, soil- and residue-borne pathogens, and pathogens such as root colonizers and viruses that survive in live tissue, may increase in importance in a perennial grain crop. Resistance genes will undeniably be important defenses against disease. However, it is seldom, if ever, possible to incorporate within a single cultivar resistance to all existing and future important diseases. Furthermore, genes vulnerable to ‘boom and bust’ cycles are generally short-lived when deployed in monocultures. For these reasons, the use of mixtures of crop cultivars or species that vary in resistance functions will likely be an important strategy for managing diseases and pests of perennial grains. Burning of plant residue, a natural phenomenon in native perennial grass systems, may also be an effective disease management strategy. The successful implementation of these management tools may reduce or eliminate the risk that perennial grain crops will become pathogen refugia that affect neighboring annual plantings and the productivity of perennial plants.
Agronomic performance of Pesticide Free Production under two crop rotations
- A. Schoofs, M.H. Entz, R.C. Van Acker, J.R. Thiessen Martens, D.A. Derksen
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- 12 February 2007, pp. 91-100
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Pesticide Free Production (PFP) is a pesticide reduction system that removes in-crop pesticide use on a yearly basis. A long-term study was established in 2000 to investigate the effect of crop rotation and frequency of inclusion on the success of PFP, as well as the effect of PFP on subsequent crops in the rotation. The crop rotations being compared were linola–oat–canola–wheat and linola–oat–alfalfa–alfalfa. PFP occurred either once in the rotation (oat) or twice (linola–oat). Weed density and yield were measured in the crops that followed PFP. Oat was a more successful PFP crop than linola because it was better able to compete with weeds. Furthermore, PFP oat had a higher weed density when it followed PFP linola, but this did not influence PFP oat yield. Under the conditions of this study, PFP linola was more successful in the annual crop rotation. Inclusion of alfalfa hay crops in the crop rotation was not effective in lowering weed pressure and, in fact, may have contributed to an increase in weed density. It is concluded that weed species present influenced the effectiveness of alfalfa in facilitating PFP, because major weeds in the study are not effectively controlled by alfalfa. PFP did not have a negative effect on following crops in the rotation (i.e. canola–wheat or alfalfa), regardless of whether one or two consecutive years of PFP occurred in the rotation. No additional herbicide was necessary for weed control in the crops that followed PFP; however, alfalfa hay was weedier for the first year following PFP. This study indicates that PFP is a viable way to reduce herbicide use in a cropping system and that attention needs to be paid to PFP crop selection and crop rotation, particularly when the PFP crop is less competitive with weeds.
An integrated approach to crop/livestock systems: Forage and grain production for swath grazing
- D.L. Tanaka, J.F. Karn, M.A. Liebig, S.L. Kronberg, J.D. Hanson
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- Published online by Cambridge University Press:
- 12 February 2007, pp. 223-231
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Current agricultural systems are the result of decoupling crop/livestock enterprises for short-term economic gain at the expense of long-term sustainability. Objectives of our research were to determine the influences of winter grazing dry gestating beef cows on no-till forage and grain production, water-use efficiency, and protein and phosphorus (P) production for an oat/pea–triticale/sweet clover–corn 3-year cropping system. Oat/pea and triticale crops were harvested for grain, with the straw and chaff left in swaths after harvest for winter grazing. Drilled corn for forage was swathed in late September. Cropping system treatments were: (1) straw and corn chopped and left in place (IP); (2) straw and corn baled and removed without livestock (R); and (3) straw and corn swath grazed by livestock (L). The first winter for grazing dry, bred cows was in 1999–2000; therefore, no treatment differences occurred for the 1999 crop. In 2000, oat/pea and triticale grain and straw production for the IP treatment was about half of the production for the R treatment, because of low oat/pea and triticale plant stands on the IP treatment. Averaged over all years, corn was about 1.5 times more efficient in using water for dry matter production when compared to oat/pea or triticale. Generally, protein and P production, on a unit area basis, were highest for corn and lowest for triticale. Averaged over 4 years, about half of the nitrogen used for protein production was derived from sources other than applied commercial fertilizer. Data suggest that more than 4 years of research are needed to understand cropping system and animal interactions on forage and grain production in integrated crop/livestock systems, with trends in year four suggesting that livestock may enhance forage and grain production.
Consumer perceptions and demand for organic food in Australia: Focus group discussions
- Hui-Shung Chang, Lydia Zepeda
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- 12 February 2007, pp. 155-167
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In Australia, the retail value of organic food production was estimated at A$250 million, with farm-gate value at around A$90 million and exports at around A$40 million, in 2002. The current share of organic sales in total food sales in Australia is about 1%. The growth rate in organic production was forecast to continue at 10–30% per annum. Despite the positive outlook, there are consumer concerns about product recognition and product integrity. To understand how demand for organic products is changing, it is important to investigate consumer attitudes and knowledge about these issues. The objective of this study was to identify issues that may hinder or promote demand. Given the qualitative nature of these issues, we used a focus group study to probe consumers. While focus group results are a qualitative approach and not intended to be generalizable, the results suggest directions for future research. The participants raised concerns about the use of chemicals, the treatment of farm animals and the environmental impact of food production. Organic food consumers were found to be more knowledgeable about organic foods, as well as being more tolerant of higher prices and inaccessibility. The results also suggest that increasing consumers' awareness of organic farming and certification, as well as the availability of organic foods, may be the most effective way of moving organic foods into mainstream.
Perennial crops and endogenous nutrient supplies
- T.E. Crews
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- 12 February 2007, pp. 25-37
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Perennial cropping systems may achieve significant improvement over annual systems in the synchrony between crop nutrient demands and nutrient supplies. Improvements in nutrient synchrony would result in the reduction of nutrient losses and their associated environmental impacts. A perennial system with high levels of synchrony would also require fewer nutrient inputs, such that it may be possible to develop an agriculture that functions mostly, if not entirely, on nutrient inputs from endogenous sources (i.e., weathering of primary and secondary minerals and biological nitrogen fixation). In this paper I describe three realms of research that will inform the development of relatively high-yielding grain production systems grown on endogenous nutrient supplies: (1) improvement of nutrient synchrony through the development of perennial crops; (2) identification of soils that are in a high nutrient release phase of pedogenesis, which could balance the export of rock-derived nutrients in crop harvests; and (3) optimization of legume density, harvest index and percent nitrogen derived from the atmosphere (%Ndfa) to achieve adequate nitrogen inputs through biological fixation.
A comparison of conventional and alternative agroecosystems using alfalfa (Medicago sativa) and winter wheat (Triticum aestivum)
- Laura E. Skelton, Gary W. Barrett
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- 12 February 2007, pp. 38-47
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Natural systems agriculture is based on an understanding that natural systems are self-sustaining due to regulatory mechanisms and processes that help to ensure the long-term maintenance of the ecosystem. An agroecosystem modeled after nature should encompass greater stability and biodiversity at all levels of organization than an agroecosystem based on conventional agricultural practices. The main objective of this study was to determine whether agroecosystems modeled after nature exhibit advantages over conventional agroecosystems. Five treatments were examined: winter wheat (Triticum aestivum L.) monoculture, alfalfa (Medicago sativa L.) monoculture, strip-cropped alfalfa and wheat, and two alfalfa–wheat intercrops (one no-till and one conservation-till). Indicators of ecosystem function studied included primary productivity, soil fertility, plant nitrogen (N) concentration, and abundances of arthropod pests and predators. No fertilizers or pesticides were used prior to or during this investigation. Monoculture, strip-crop and conservation-till treatments produced significantly higher yields than no-till intercropped alfalfa and wheat. Although yields from the no-till intercrop were low, wheat protein values were comparable to other treatments. Soil N concentrations tended to be high in treatments containing alfalfa. Insect pests preferred alfalfa and were, therefore, often more abundant in treatments containing high percentages of alfalfa, as were predators such as spiders. Researching alternatives to monoculture agroecosystems, such as the intercrop systems in this study, may provide us insight into a true natural systems agriculture.
Garden production systems and food security in Ghana: Characteristics of traditional knowledge and management systems
- Emmanuel K. Yiridoe, Vincent M. Anchirinah
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- 12 February 2007, pp. 168-180
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There is limited documented scientific information on garden production systems managed in developing countries, partly because both researchers and research administrators have, until recently, ignored them as legitimate areas of study, and because such production systems have been regarded as informal production activities, managed outside conventional market and economic channels. Yet in a developing country such as Ghana, these production systems are potentially able to contribute substantially to the food security and health needs of households. This study was aimed primarily at providing critical scientific information for understanding the complex web of production and management factors associated with garden production systems. A total of 300 survey responses, representing the Sudan savannah, Guinea savannah and moist deciduous forest agro-ecological zones of Ghana, were analyzed (27% of respondents were females and 73% were males). Several hypotheses from the field agriculture literature were tested to determine their relevance in garden production systems. Although, for the country as a whole, a variety of garden crops are cultivated, each agro-ecological zone concentrated on a set of four major crops, with the actual food crops differing across agro-ecological zones. The type of protective fencing used was not statistically associated with land tenure (i.e., own versus rented land) status of the gardener (χ2=3.285, P=0.4501). Gender responsibilities in garden production and management tended to be more equally shared in the forest agro-ecology, where garden crops are cultivated for household consumption and for generating family income. In contrast, in the two savannah zones, adult males undertook a disproportionate share of activities to produce garden crops that were primarily for marketing. Valuable information on production and management exist within the traditional garden production systems studied, and range from socio-economic, agronomic and medicinal considerations in selecting garden crops and fruit trees, to ecological monitoring systems and strategies for garden management.
Internationalization of the organic fruit market: The case of Washington State's organic apple exports to the European Union
- Gregory M. Peck, Preston K. Andrews, Cindy Richter, John P. Reganold
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- 12 February 2007, pp. 101-112
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Production of some organic commodities, such as apples, is heavily concentrated in the United States (US), with Washington State being the leading US producer of organic apples. In 2003, there were 4047 ha of certified organic apple orchards in Washington State, an all-time high and a more than tenfold increase since 1989. But this growth has not occurred without difficulties. Washington State's organic apple growers have encountered international supply and demand pressures forcing them to seek new markets, such as the European Union (EU). In this paper, we explore the complexities of the international marketing of organic fruit, using organic apple production in Washington State and market opportunities for this organic fruit in the EU, as a case study. We find that as a result of the expansion of organic apple plantings in Washington State, there has been a decrease in the price premiums, which traditionally offset the greater costs of organic production and which originally motivated many Washington growers to certify their apple orchards. We also find that increased demand for organic fruits in the EU has been outpacing supply, making EU member states the most important export market for Washington's organic apples. However, despite the unification of US standards by the US Department of Agriculture (USDA) and an overriding EU standard, an entanglement of regulatory bodies from around the world is involved in the certification of organic products. For example, growers and marketers may have to interact with as many as six different regulatory bodies in order to export organic produce from the US to the EU. This study shows that while the EU market remains a promising destination for US organic apples, organic growers and marketers must plan ahead and thoroughly understand the multitude of regulations involved in the international trade of organic fruits.
An integrated approach to crop/livestock systems: Wintering beef cows on swathed crops
- J.F. Karn, D.L. Tanaka, M.A. Liebig, R.E. Ries, S.L. Kronberg, J.D. Hanson
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- Published online by Cambridge University Press:
- 12 February 2007, pp. 232-242
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Grain and livestock production have gradually been separated, as farmers have tended to specialize in one or the other. Some producers and scientists are beginning to question whether this is the best approach. An integrated crop/livestock project was initiated in 1999 to investigate potentially beneficial synergies to both enterprises. The cattle portion of this project involved wintering dry pregnant cows on swathed crop residue and drilled corn produced in a 3-year crop rotation, with all crops present each year. Swath grazing was initiated in mid-November of 1999, 2000 and 2001, and terminated in mid-February each year. Two replications of ten Hereford cows were rotationally grazed on swathed oat/pea and triticale crop residue and swathed drilled corn (RGSC). Comparison treatments were: cows grazing swathed western wheatgrass (SWWG) and cows fed hay in a drylot. Cows on the RGSC treatment were also fed a 20% crude protein supplement of oat/pea and triticale grain. Drilled corn was swathed in late September and western wheatgrass in early October. Three-year average winter-long weight gains for the RGSC cows were slightly lower (P<0.10) than those for drylot cows. Body condition scores generally followed the same pattern as weight gain data. Reproductive and calf performance data were not significantly different among wintering treatments. Average daily feed costs per cow over the three winters were US$0.49, 0.65 and 0.73 for RGSC, SWWG and baled hay in a drylot, respectively, providing a potential daily savings of US$0.24 per cow with the RGSC treatment compared to bale feeding in a drylot. Swath grazing did not appear to have any adverse affects on mid-aged beef cow performance and could potentially reduce winter feeding costs and manure handling problems. The main problem with swath grazing is potentially deep snow and icing of the swaths.