The heavy use of inorganic fertilisers in arable farming has led to serious environmental problems. Organic farming methods require inputs of large volumes of organic material and yields do not compete with conventional farming. This project will research and develop new nitrogen (N) -fixing bacterial inoculants for cereal crops, which can substitute inorganic fertilisers or add value to compost. Inoculants have been established for legumes, but no equivalent for non-legumes is available. Some recently discovered strains do interact with cereal plants, but they are vulnerable to high losses during storage and application. The project will isolate and test new strains as well as researching various delivery modes, including compost and micro-encapsulation, which will improve the survival of the bacteria during storage and application.
Micro-N-fix will research new nitrogen-fixing bacterial inoculants as a substitute for inorganic fertilisers, and add value to organic fertilisers. New strains of N-fixing bacteria will be selected with desirable characteristics for use in inoculants and three delivery modes will be developed: compost, micro-encapsulation and seed coating. These will give a greater shelf life and increase the quantity of bacteria active in the soil, with the aim of further increasing the amount of nitrogen fixed to the plants.
Progress to Date
The end user partners, Bio-gen, Dalgety and AGRON, have produced a specification of end user requirements that provides targets for the performance and cost of the inoculants.
The partners are using their own strain collections and samples of wheat roots collected around Europe to identify and characterise novel nitrogen-fixing bacteria. Methods for assessing the strains are being established. Potential candidates were first isolated on a nitrogen-free medium and then characterised by PCR and general observation of phenotype. Preparations are underway to test the nitrogen-fixing capacity of the lead candidates using the standard acetylene reduction test, but also by two alternative techniques that are being developed by the partners. The first year trials are intended to provide baseline data, and a reference strain of Azospirillum (known to fix nitrogen to wheat) has been selected for application on wheat and maize in field trials, as well as in greenhouse pot trials. Root samples of the winter field trials with wheat are currently being analysed with PCR to assess success of root colonisation.
The first experiments have been performed for seed coating and suitable materials are being selected for micro-encapsulation of the bacteria. Work has commenced on identifying suitable composts for application of the inoculants in organic farming.
Around 25 nitrogen-fixing strains were identified for further study. The first pot experiments with wheat and different inocula containing Azospirillum showed weak differences between treatments. The first season of field trials in Israel are nearing completion and an evaluation of the results is in progress.
CEREALS, ARABLE CROPS
Scientist responsible for the project
Professor NICOLAUS von WIRÉN
Institute of Plant Nutrition, University of Hohenheim Box -
70593 Stuttgart CEDEX -
Germany - DE Region NUTS -
Phone: +49 711 4592344
Fax: +49 711 4593295
||UNIVERSITY OF HOHENHEIM
||10 January 2002
||2 643 103 €
|Total EC contribution
||1 625 467 €
|Web address of the project