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Improving P supply in organic farming systems - LK0963

UK Organic Action Plans (Defra, SEERAD) aim to increase the proportion of the organic food market met by indigenous production to 70%; this would increase the area of organic arable cropping. Phosphorus (P) management must be optimised to meet yield and quality requirements. The use of soluble P fertilisers e.g. triple superphosphate, is prohibited in organic farming (EC Regulations 2092/91 and 1804/99; see Annex 1). Minimally processed phosphate rock (PR) can be used but it has low solubility at the optimum soil pH (~ 6.5) for cropping. Establishing and maintaining the balance between P supply to sustain production and minimise diffuse P loss is a major issue1 and Defra is developing an action plan to reduce diffuse water pollution from agriculture which is likely to target inter alia the increased efficiency of P use. P efficiency in rotations could be increased by the targeted inclusion of crops and cultivars with high P uptake efficiency2. The fermentation of crop residues or green wastes with PR also has potential to increase P availability to crops 3. Neither approach has yet been widely tested in the field and not at all in the UK. For best management practice for P on organic farms to be formulated, a more detailed understanding of soil-plant P interactions is required4. This project will integrate and test novel approaches to the use of PR within organic crop rotations.
Develop the biotechnological solubilisation of P from PR to yield an effective low-cost P fertilising material
Quantify the availability of P from PR in arable crop rotations following fermentation or composting with organic vegetable wastes
Quantify the impact of rotation design and P sources (PR, composted and fermented products) on P offtake in harvestable produce
Quantify the environmental and economic costs and benefits of new versus traditional approaches to P management in organic farming systems
Time-Scale and Cost
From: 2005

To: 2010

Cost: £311,680
Contractor / Funded Organisations
The Bulmer Foundation, Mark Measures Associates, Organic Farm Foods Ltd., Edward Bulmer, Scottish Organic Producers Assoc, University - Scottish Agricultural College, TIO Ltd., University - Newcastle, Organic Recycling Ltd, Soil Association Certification, SAC Commercial Ltd, Abbey Home Farm
Arable Farming              
LINK Programme              
Organic Farming              
Sustainable Farming and Food              
Sustainable Production              
Fields of Study
Organic Farming