The use of animal manure from conventional livestock systems is a contentious input that Organic-PLUS aims to phase-out of organic agriculture. There are, however, a number of uncertainties associated with on-farm produced compost including its chemical and biological composition. Therefore, we re-evaluated plant-based sources (e.g. olive branch prunings, medicinal and aromatic plant residues, and freshly cut grass) carried out in replicated trials (n=3) at the Olive Research Institute (ORI) in Izmir, Turkey, in order to make a number of recommendations to help minimise risks for farmers. Our results show that the quality of the end product can be affected by the compost heap size (height and width), the microorganisms present, by monitoring the moisture and temperature of the heap, the timing of compost heap turning and the size and moisture content of plant residue particles prior to composting. Our data also indicate that reduced (2% of total heap volume), or zero, manure in farm composts as no detrimental effects on the composts’ chemical quality. After maturing for 8 months the compost had the following composition: nitrogen (2.01%), phosphorus (0.12%), potassium (1.41%), organic matter (57.95%) and total organic carbon (17.02%). This is considered ‘rich’ under the legislation framework for compost quality in Turkey. In addition, the Carbon/Nitrogen (C/N) ratio was 35/1, which is an acceptable level for olive branch pruning and medicinal and aromatic plant residue-based composts after 8 months on-farm. However, research will continue until the C/N ratio of compost decreases to 20-25/1 level. alev.kir.etae@gmail.com

Waste from organic aquaculture such as fish pond sediments is a potential ingredient for compost that can be used to improve soil properties and plant growth. The Organic-PLUS project is interested in recycling and reusing fertilisers, as this could be a pathway to replace contentious inputs like manure from intensive conventional systems, or possibly peat in growing media (peat is an industrially mined product with a high carbon and environmental cost, seen as a contentious input by many consumers). To test the hypothesis that fish pond sediments could be a replacement for contentious inputs, a laboratory experiment was designed. The substrates used in the experiment were fish pond sediments from organic rainbow trout farming, mixed with fresh grass and wheat straw. Fish pond sediments accumulate in significant quantities at the bottom of ponds and pose a threat to the environment, (even though organic fish pond stocking densities are 30-40% lower), limiting the flow of oxygen and water in the lower layers of pond. One way to manage and utilise excessive amounts of fish pond sediments could be to compost them. Our laboratory experiment has shown that the compost from organic fish pond sediments demonstrates good fertilising potential. In the first week of composting, a temperature of about 52–61°C was reached. The high temperature in the composter lasted for several days, reducing the number of pathogenic microorganisms. Combining compost from fish pond sediments with cardboard and biochar from wood chips increased the content of organic matter, phosphorus and carbon. We also found that the addition of these ingredients had a significant effect on the growth of beans. (danuta.drozdz@pcz.pl, kmalinska@is.pcz.pl)

In the last few years, due to the growing incidence of anthelmintic resistance, plants have increasingly been considered an alternative for the prevention and treatment of parasitic infestations, as well as an alternative to antimicrobics. The Organic-PLUS project is interested in alternatives to contentious inputs like antibiotics, widely used in conventional livestock systems but also in organic livestock (to a very limited degree).

We conducted a trial of potential antiparasitic molecules with the aim of identifying the anthelmintic activity of three different plant extracts (Malva sylvestris, Chamomilla recutita and Althaea officinalis). Based on the parasitic count through Larval development test (LDT) and Egg hatch test (EHT) specifically for Haemonchus contortus, we found no differences in effect between the plant extracts at dilutions from 0.019 mg/ml to 10 mg/ml. The mean number of eggs and larvae forms appeared to be considerably lower than the control when using plant extracts in the concentration of 10 mg/ml and higher. It was interesting to see higher numbers of parasite forms in the Chamomilla recutita treatment in comparison to Malva sylvestris and Althaea officinalis starting from the concentration of 1.25 mg/ml, that became significant at the concentration of 20 mg/ml. Similar studies are being carried out where other plant products are tested against different pathogenic bacteria. These tests are fundamental to forming in-field recommendations on the use of herbal products. Giulio Grandi giulio.grandi@slu.se and Federico Righi federico.righi@unipr.it

Conventional bedding pellets for poultry usually consist of a mixture of wood shavings/chips and chopped straw, which is not certified organic and can contain considerable amounts of herbicides and pesticides. This is seen to be contentious by most organic consumers. For cattle, chopped and baled straw is used which has longer and rougher fibres. An additional worry is that cattle may eat conventional straw leading to pesticides entering the organic food chain. Therefore, there is an urgent need for alternatives. Organic straw is not produced in high enough quantities and is difficult to source. In addition, transportation costs of organic straw can be high when shipped from locations far away.

To find alternatives a variety of plant sources are being tested for their suitability as a straw replacement in bedding at ATB, Potsdam, Germany. Using existing technology, properties of bedding pellets can be improved if processed from woody (lignocellulosic) material with an extruder and pelleting machine at exact settings. An additional line of inquiry is whether the plant materials have beneficial properties for animal health.

Preliminary results show that there is potential for other advantages for the animals besides the primary function of bedding, but more work is now required to determine the most suitable sources. Different settings of the extruder or hammer mill combined with properties of the raw material have an influence on the fibre and pellets that are produced. This means there is a large number of tests required to adjust the pilot plant extruder, hammer mill and ring-die-press to specific settings.

Christian Dittrich, CDittrich@atb-potsdam.de and Dr Ralf Pecenka RPecenka@atb-potsdam.de

In aubergine plant genetic resources there is huge range of resistance to early blight (Alternaria solani). Therefore, the choice of variety is important, to avoid the contentious use of copper or other fungicides in growing organic aubergines. The Organic-PLUS project is interested in how genetic diversity in local landraces can take the need of copper fungicides away and make the zero–copper production of Mediterranean vegetables possible.

Turkey is one of the most significant countries in the world regarding plant genetic resources and plant diversity. This is also true of vegetable plant species including aubergine (Solanum melongena L.). Among the 65 landraces of aubergine that were identified, it was then tested how high the resistance level was to the commonly spread fungi. Early blight disease can cause much damage in organic horticulture. The testing was done by incubating petri dishes with Alternaria spores (24 0C) for 7 days and then putting two aubergine leaves on the dishes with 6 replications and 2 controls. They were left there for 8 days and analysed for infection. A 0-5 scale was used for scoring.

Results showed that 14 out of 65 landraces showed moderate resistance against early blight and a further 14 varieties had very high tolerance. The landraces were morphologically characterised, regenerated and multiplied to send the seeds and details of traits to “Turkish Seed Gene Bank” (Ankara, Turkey). This means that the material and characterisation information is ready for further investigation by breeders’ research programs under the framework of an international Gene Bank rules to achieve utilisation of them at farm scale.

Dr Alev Kir alev.kir.etae@gmail.com

The use of copper for the control of fungal or bacterial diseases in organic farming has been, and still is, prevalent for greenhouse and olive crops in the Mediterranean European countries. The mentioned diseases are difficult to prevent and it is necessary to apply copper therapeutic treatments once the conditions for the disease arise. However, the repeated use of cupric formulations results in their accumulation in soils, with undesirable effects on crops and soil organisms (biota). After identifying authorised alternatives to copper, without containing microorganisms: phytosanitary products and basic substances (Table 1), two representative pathogens (Botrytis cinerea and Colletotrichum sp. Fig. 1, 2) were, in the laboratory, used to compare the fungistatic/fungicide effect of the alternatives with copper oxychloride (50%) (COX).

Potassium hydrogen carbonate and lime sulphur, two products with a moderate price for the grower, showed a good response against both fungi, better than COX. Also, some plant extracts were tested, and two different Cinnamon extract products were better than COX, too. The cost of applying these extracts is also moderate, however these extracts are not authorised as phytosanitaries. In summary, three accessible alternative products to copper can be used by growers, thus allowing the reduction or avoidance of copper applications.

If you would like to find out more about this research, please contact:

Francisco Miguel de De Cara-García franciscom.cara@juntadeandalucia.es