Alarmingly, that is the estimated upper limit of the cost of nitrate pollution in Europe, much of which results from use of nitrogen-based fertilisers to overcome nitrogen insufficiency in the soil for crop growth. A major problem associated with over-use of nitrate fertilisers on the land is water-based eutrophication, specifically human-caused cultural eutrophication, which is bad news for all of us, and something to be avoided if possible.
Trying to avoid such environmental damage – and maybe save some money as well – by releasing plants from their dependence upon externally supplied N compounds, a new technology aspires to convert crops that don’t normally harbour N-fixing bacteria (such as legumes) into plants that can use the nitrogen that is freely available in the atmosphere and fix it into compounds that the plant is able to use. The treatment – known as N-Fix and developed by Prof. Edward Cocking (Director of The University of Nottingham’s Centre for Crop Nitrogen Fixation) – exploits the ability of a specific strain of N-fixing bacteria found in sugar-cane, Gluconacetobacter diazotrophicus, that can colonise cells of all major crop plants. The technology has been licensed by The University of Nottingham to Azotic Technologies Ltd and is delivered as a bacterial coating to the seeds. Importantly, it is stressed that the process is neither genetic engineering/modification (GE/GM) nor ‘bio-engineering’. Rather, N-Fix is seen as a natural seed coating that provides a sustainable solution to fertiliser overuse and nitrogen pollution, is environmentally friendly and can be applied to all crops.
Does this sound too good to be true? Well, 10 years of a series of extensive research programmes have established proof of principle of the technology in the laboratory, growth rooms and glasshouses. If this can be scaled up to sustainable levels in the field, this application has enormous implications for agriculture as the technology could provide much of the plant’s nitrogen needs, reducing costs – both monetary and environmental – of expensive synthetic nitrogen fertiliser. Still, one wonders how widely available – and affordable – these seeds will be to those farmers in the poorest areas of the planet most in need of such an N-Fix.
[In addition to the press release’s associated video, for more on the science and potential of this fascinating story, try Cocking et al.’s ‘Intracellular colonization of roots of Arabidopsis and crop plants by Gluconacetobacter diazotrophicus’, Raúl Pedraza’s ‘Recent advances in nitrogen-fixing acetic acid bacteria’, Ted Cocking and Philip Stone’s online poster, and the ‘Complete genome sequence of the sugarcane nitrogen-fixing endophyte Gluconacetobacter diazotrophicus Pal5’ by Marcelo Bertalan et al. – Ed.]