[Show abstract][Hide abstract] ABSTRACT: To evaluate the influence of compost on soil fertility and plant growth, several medium term and long term field experiments with composts were conducted in different crops.
In two maize experiments, one in a sandy and one in a loamy soil, the influence of different composts and digestates on soil parameters and plant growth were investigated. All products increased pH of the soil and improved the biological soil activity (e.g., enzymatic activities). Immature compost immobilized nitrogen and reduced plant growth. Organic nitrogen fertilizer added during cultivation, could compensate the growth depression.
A full factorial experiment in a 2-years-old organic apple orchard was conducted from 2001-2007. The factors tested in all 9 possible combinations were: i) biowaste compost, ii) commercial organic N-fertilizer, iii) foliar N-fertilizer. In spring, the highest values for mineralized N (Nmin) in the tree strip were found in the treatment with commercial organic N-fertilizer, with addition of compost it was 75%, and biowaste compost alone reached 50% of this value on average, whereas unfertilized plots had the lowest but still sufficient values for the same tree performance and fruit nutrition as fertilized plots.
In the DOK long-term field trial, three farming systems are compared since 1978: i) mineral and organic fertilisers, synthetic pesticides; ii) organic fertilisers, mechanical weeding and biological disease and pest control; and iii) composted manure and bio-dynamic preparations. A conventional system with mineral fertilisers only and an unfertilized treatment serve as controls. Soil fertility mirrored by soil biological parameters, soil biodiversity and soil organic matter are higher in the organic systems and render these systems less dependent from external inputs.
[Show abstract][Hide abstract] ABSTRACT: Europe is both a leading world market for and world producer of organic food. Growth of organically managed land and of domestic market values was strong in the past and continued during the financial recession, although at a slower rate. Many countries have specific plans for priority organic research and investment. Europe is a major producer of organic fruit crops, including a total of more than 900,000 ha consisting of 367,000 ha of olives, 92,700 ha of grapes, 187,000 ha of nuts, 94,800 ha of temperate fruit, 26,096 ha of berries, 31,800 ha of citrus, and 11,000 ha of subtropical fruit (2010). Western Europe added 4,000 ha of organic apples (Malus ×domestica) in 2010 and 2011 due to growth of the organic fruit market, a decline in conventional fruit prices, and improved organic production methods and input products. Market saturation has occurred in years of high organic apple yields, and thus organic fruit growers and retailers are working to gain new customers, especially lifestyle of health and sustainability (LOHAS) consumers. Tools to help organic fruit growers better evaluate farm economics (e.g., 'Arbokost') are available and needed as increased prices are often nearly matched by increased production costs. New disease control products and models are helping address key fruit diseases such as apple scab (Venturia inaequalis) and sooty blotch (Gloedes pomigena and Schizotorium pomi), yet barriers for other fruits remain. As conventional fruit production embodies more sustainability and reduces pesticide residues, consumers' perceived added value of organic fruit could diminish. Research at the Swiss Research Institute of Organic Agriculture (FiBL) and elsewhere is attempting to redesign organic fruit systems to be more self-regulating by choosing fruit genetics that minimize input needs and increasing biodiversity in the farm ecosystem, thus continuing to distinguish organic production from other methods.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to provide an ex ante assessment of the sustainability of genetically modified (GM) crops under the agricultural conditions prevailing in Switzerland. The study addressed the gaps in our knowledge relating to (1) the agronomic risks/benefits in production systems under Swiss conditions (at field and rotation/orchard level), (2) the economic and socio-economic impacts associated with altered farming systems, and (3) the agro-ecological risks/benefits of GM crops (at field and rotation/orchard level). The study was based on an inventory of GM crops and traits which may be available in the next decade, and on realistic scenarios of novel agricultural practices associated with the use of GM crops in conventional, integrated, and organic farming systems in Switzerland. The technology impact assessment was conducted using an adapted version of the matrix for “comparative assessment of risks and benefits for novel agricultural systems” developed for the UK. Parameter settings were based on information from literature sources and expert workshops. In a tiered approach, sustainability criteria were defined, an inventory of potentially available, suitable GM crops was drawn up, and scenarios of baseline and novel farming systems with GM crops were developed and subsequently submitted to economic, socio-economic, and agro-ecological assessments. The project had several system boundaries, which influenced the outcomes. It was limited to the main agricultural crops used for food and feed production and focused on traits that are relevant at the field level and are likely to be commercially available within a decade from the start of the project. The study assumed that there would be no statutory restrictions on growing GM crops in all farming systems and that they would be eligible for direct payments in the same way as non-GM crops. Costs for co-existence measures were explicitly excluded and it was assumed that GM foods could be marketed in the same way as non-GM foods at equal farm gate prices. The following model GM crops were selected for this study: (1) GM maize varieties with herbicide tolerance (HT), and with resistance to the European corn borer (Ostrinia nubilalis) and the corn rootworm (Diabrotica virgifera); (2) HT wheat; (3) GM potato varieties with resistance to late blight (Phytophthora infestans), to the nematode Globodera spp., and to the Colorado beetle (Leptinotarsa decemlineata); (4) HT sugar beet with resistance to “rhizomania” (beet necrotic yellow vein virus; BNYVV); (5) apples with traditionally bred or GM resistance to scab (Venturia inaequalis), and GM apples with stacked resistance to scab and fire blight (Erwinia amylovora). Scenarios for arable rotations and apple orchards were developed on the basis of the model crops selected. The impact assessments were conducted for the entire model rotations/orchards in order to explore cumulative effects as well as effects that depend on the farming systems (organic, integrated, and conventional). In arable cropping systems, herbicide tolerance had the most significant impact on agronomic practices in integrated and conventional farming systems. HT crops enable altered soil and weed management strategies. While no-till soil management benefited soil conservation, the highly efficient weed control reduced biodiversity. These effects accumulated over time due to the high proportion of HT crops in the integrated and conventional model rotations. In organic production systems, the effects were less pronounced, mainly due to non-use of herbicides. Traits affecting resistance to pests and diseases had a minor impact on the overall performance of the systems, mainly due to the availability of alternative crop protection tools or traditionally bred varieties. The use of GM crops had only a minor effect on the overall profitability of the arable crop rotations. In apple production systems, scab and fire blight resistance had a positive impact on natural resources as well as on local ecology due to the reduced need for spray passages and pesticide use. In integrated apple production, disease resistance increased profitability slightly, whereas in the organic scenario, both scab and fire blight resistance increased the profitability of the systems substantially. In conclusion, the ecological and socio-economic impacts identified in this study were highly context sensitive and were associated mainly with altered production systems rather than with the GM crops per se.
Agronomy for Sustainable Development 01/2013; 33(1). DOI:10.1007/s13593-012-0088-7 · 3.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In recent years, an increasing market for blueberries has developed in Switzerland. Blueberries are well suited for organic production because few disease and insect pests are currently found under Swiss conditions. Soil conditions present the greatest obstacle to blueberry cultivation in that Swiss soils are often too alkaline and have low soil organic matter content. During a nine-year (1998-2006) field experiment on an alkaline soil, we tested the feasibility and plant performance of three peat-free cultivation systems (deep ditch, flat ditch, raised bed) and two acidification methods (sulfur or citric acid versus an untreated control). Cultivars were 'Bluecrop' and 'Reka'. The vegetative growth of the bushes was not significantly affected by the cultivation systems. However, the deep ditch system obtained produced significantly higher yields (6.04 kg) compared with the raised bed system (5.13 kg). The yield in the flat ditch system (5.96 kg) was not significantly different from either of the other two systems. Lowering pH levels in the substrate sufficiently (pH<4.8) was achieved only with sulfur (30 g/plant/y). The acidification treatments affected the shrub development and yields significantly. Compared with the untreated control, shrub volume (+43%) and accumulated yield (+55%) were greater in the treatment with application of sulfur. With the citric acid treatment, shrub volume and yield were increased by 12% and 9%, respectively. Root growth and biomass showed no differences between the cultivation systems. A flat ditch with pine sawdust combined with acidification by sulfur offers good plant growth and yield performance and is cheaper to install compared with deep ditch. Based on these results, we have recommended this cultivation system with sulfur applications for commercial blueberry production in regions with alkaline soils in Switzerland since 2005.
[Show abstract][Hide abstract] ABSTRACT: The organic food sales have been increasing during the recent years. It has been hypothesised that organically grown fruits are healthier based on their higher content of phytochemicals. However, data on the bioavailability of phytochemicals from organically or conventionally produced plant foods are scarce.
Two human intervention studies were performed to compare the bioavailability of polyphenols in healthy men after ingestion of apples from different farming systems. The administered apples were grown organically and conventionally under defined conditions and characterised regarding their polyphenol content and antioxidant capacity. No significant differences in the polyphenol content and the antioxidant capacity from the organic and conventional farming system were observed.
In the short-term intervention study, six men consumed either organically or conventionally produced apples in a randomized cross-over study. After intake of 1 kg apples, phloretin (C (max) 13 + or - 5 nmol/l, t (max) 1.7 + or - 1.2 h) and coumaric acid (C (max )35 + or - 12 nmol/l, t (max) 3.0 + or - 0.8 h) plasma concentrations increased significantly (P < 0.0001) in both intervention groups, without differences between the two farming systems. In the long-term intervention study, 43 healthy volunteers consumed organically or conventionally produced apples (500 g/day; 4 weeks) or no apples in a double-blind, randomized intervention study. In this study, 24 h after the last dosing regime, the apple intake did not result in increasing polyphenol concentrations in plasma and urine compared to the control group suggesting no accumulation of apple polyphenols or degradation products in humans.
Our study suggests that the two farming systems (organic/conventional) do not result in differences in the bioavailability of apple polyphenols.
European Journal of Nutrition 08/2010; 49(5):301-10. DOI:10.1007/s00394-009-0088-9 · 3.47 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Different research groups have already proven that flowering plants in orchards can enhance beneficial arthropods. Even within the tree rows different beneficial can be supported by selected plant species. In most experimental work done to stabilize the apple production system only single interaction effects were tested. However until now, no research group has quantified the additive effects of multiple measures on systembiodiversity and on the production economy.
Our experiment combines all known measures of indirect pest and disease control measures in a near-to practical production model orchard without the use of any pesticide (not even organic ones). The orchard is split in 4 blocks: in two of them bio-control measures e.g. application of Granulosis Virus against codling moth (C. Pomonella) are applied; in the other two blocks no bio-control is applied. Standard commercial organic and integrated orchards with the disease-susceptible cultivar Gala in the vicinity of the model orchard are assessed by the same methods and serve as reference.
Our intermediate results reveal that the self-regulating orchard developed already in the 2nd and 3rd leaf a clearly higher flora and fauna biodiversity compared to the reference orchards. The same happened in relation to the specific fruit beneficial e.g. the populations of aphid predators. In the self-regulating orchard they were capable to keep the aphid damages – in particular of the powdery apple aphid (D. plantaginea) - on trees and fruits under a commercially relevant level although the initial abundance of aphid colonies in spring was by far over the common threshold value. It is planned to continue the experiment until 2016.
Proceedings of the 14th International Conference on Organic Fruit Growing from February 22nd to February 24th., Weinsberg; 01/2010
[Show abstract][Hide abstract] ABSTRACT: The present study was performed to evaluate the polyphenol content and antioxidant capacity of apples (cv. ;Golden Delicious') grown under defined organic and conventional conditions. Apples were harvested at five comparable commercial farms over the course of three years (2004-2006). In 2005 and 2006 the antioxidant capacity was 15% higher (p < 0.05) in organically produced apples than in conventionally produced fruits. In 2005 significantly higher polyphenol concentrations were found in the organically grown apples. In 2004 and 2006 no significant differences were observed (2004, 304 +/- 68 microg/g organic vs 284 +/- 69 microg/g conventional, p = 0.18; 2005, 302 +/- 58 micro/g organic vs 253 +/- 41 microg/g conventional, p = 0.002; 2006, 402 +/- 100 microg/g organic vs 365 +/- 58 microg/g conventional, p = 0.17). Year-to-year variations in the antioxidant capacity and the polyphenol content of up to 20% were more significant than the production method found within one year. Finally, flavanols and flavonols were major determinants of the antioxidant capacities in these apples. Overall, the production method had a smaller impact on the variation in the polyphenol content and antioxidant capacity of apples than the yearly climate.
Journal of Agricultural and Food Chemistry 05/2009; 57(11):4598-605. DOI:10.1021/jf803961f · 2.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Production of Vaccinium corymbosum L. is limited to acidic soils with high organic matter content. This specific soil requirement is limiting the possibilities to cultivate V. corymbosum L. in many regions of Central Europe. The aim of this study was to overcome the limiting production factors occurring under the soil and climate conditions of Switzerland: (1) evaluation of natural growing substrates without peat as required for organic production; (2) adjustment of the optimal pH in the growing substrate; (3) regulation of water issues (water quality and mulching) and (4) development of a suited planting system. Pine sawdust was evaluated to be the best alternative growing substrate compared to peat moss. Optimal pH adjustment in pine sawdust substrate was found to be 3.8 (CaCl2) and 4.2 (H2O). In field cultivation, an amount of 30 g S year-1 plant-1 to lower the pH of the pine sawdust ditches was sufficient for good plant and yield development. This acidification resulted in better growth (+48%) and higher yield (+55%) when alkaline ground water (357 mg L-1 CaC03) was used for irrigation. Acidification with citric acid gave poor results. A mulch of pine bark on the sawdust ridge increased growth by 59% and yield by 25%.The newly developed flat ditch system with low sawdust ditches buried partly into the ground was as suitable as the standard planting system with deep ditches lined with plastic film. By integration and application of these new findings, a system for commercial organic blueberry production under Swiss conditions and on alkaline soils was developed.
European Journal of Horticultural Science 01/2009; 74(3):103-111. · 0.30 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The effects of organic and integrated production systems on the culturable fungal microflora of stored apple fruits from five matched pairs of certified organic and integrated 'Golden Delicious' farms were studied at five representative production sites in Switzerland. Isolated fungi were identified morphologically. Colonization frequency (percentage of apples colonized), abundance (colony numbers), and diversity (taxon richness) were assessed for each orchard. The standard quality of the stored fruits was comparable for both organic and integrated apples and complied with national food hygiene standards. Yeasts (six taxa) and the yeast-like fungus Aureobasidium pullulans were the dominant epiphytes, filamentous fungi (21 taxa) the dominant endophytes. The most common fungi occurred at all sites and belonged to the "white" and "pink" yeasts, yeast-like A. pullulans, filamentous fungi Cladosporium spp., Alternaria spp., and sterile filamentous fungi. Canonical correspondence analysis of the total fungal community revealed a clear differentiation among production systems and sites. Compared to integrated apples, organic apples had significantly higher frequencies of filamentous fungi, abundance of total fungi, and taxon diversity. The effects of the production system on the fungal microflora are most likely due to the different plant protection strategies. The incidence of potential mycotoxin producers such as Penicillium and Alternaria species was not different between production systems. We suggest that higher fungal diversity may generally be associated with organic production and may increase the level of beneficial and antagonistically acting species known for their potential to suppress apple pathogens, which may be an advantage to organic apples, e.g., in respect to natural disease control.
[Show abstract][Hide abstract] ABSTRACT: The present study was performed to compare the effects on antioxidant activity and on DNA damage of organic and conventionally produced apples grown under controlled conditions in human peripheral blood lymphocytes. Six healthy volunteers consumed either organically or conventionally grown apples (Golden Delicious, 1000 g) from two neighboring commercial farms in a double-blinded, randomized, cross-over study. The average content of total identified and quantified polyphenols in the organically and conventionally produced apples was 308 and 321 microg/g fresh weight, respectively. No statistically significant differences in the sum of phenolic compounds or in either of the polyphenol classes were found between the agricultural methods. Consumption of neither organically nor conventionally grown apples caused any changes in antioxidant capacity of low-density lipoproteins (lag time test), endogenous DNA strand breaks, Fpg protein-sensitive sites, or capacity to protect DNA against damage caused by hydrogen peroxide. However, a statistically significant decrease in the levels of endonuclease III sensitive sites and an increased capacity to protect DNA against damage induced by iron chloride were determined 24 h after consumption in both groups of either organic or conventionally grown apples, indicating the similar antigenotoxic potential of both organically and conventionally grown apples.
Journal of Agricultural and Food Chemistry 10/2007; 55(19):7716-21. DOI:10.1021/jf0710534 · 2.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Damages caused by the larvae of Byturus tomentosus (Coleoptera: Byturidae) are a big problem of European raspberry production. Under integrated pest management conditions in Switzerland, B. tomentosus is controlled by chemical-synthetic insecticides. In organic production, no corresponding insecticides are permitted. White sticky traps (type Rebell® bianco) are used for monitoring purposes. Can glue-traps also be used for mass-trapping and damage control? In this study, the attractiveness for adult B. tomentosus of one yellow and several white glue-traps was compared by counting the trapped individuals. Trapped beneficial insects like honey bees, Coccinellidae, Syrphidae and Chrysopidae were also counted. The contamination of the traps caused by other non-target arthropods was measured by a computer-assisted method. The white sticky trap type Rebell bianco was the most attractive for B. tomentosus. The attractiveness for the beneficials was relatively low, except when too much glue was applied on the traps, then the attractiveness for honey bees increased significantly. In this study, traps, which were placed in high densities (17 traps per 100m2), significantly decreased the damages caused by larvae by around 40%. The trapping method does not cause any residuals of pesticides on the fruits or soil. Therefore, the trapping method could be an alternative to control B. tomentosus, especially in organic production.
Journal of Pest Science 07/2006; 79(3):137-142. DOI:10.1007/s10340-006-0126-9 · 2.64 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: L'évaluation des nouvelles variétés fait partie du programme de recherche du FiBL. Elle se fait dans le cadre d'essais précis et aussi chez les producteurs. A Frick les essais se font en conditions "extrêmes", c'est à dire sans traitement contre les pucerons, sans éclaircissage et sur les arbres plus âgés, sans traitement contre l'oïdium et la suie. Ces conditions permettent d'apprécier les nouvelles variétés dans l'environnement difficiles de la production bio. Les remarques des praticiens sont les bienvenues!
[Show abstract][Hide abstract] ABSTRACT: La culture biologique de fruits à pépins s’est fortement développée au cours de ces dernières années : les superficies actuellement plantées permettent d’obtenir des récoltes plus ou moins à la hauteur de la demande du marché. Moyennant quelques efforts, il devrait être possible d’augmenter encore cette production, à tous les niveaux, mais à un rythme ralenti.