The nitrogen crisis in agriculture and potential solutions using biological nitrogen fixation
Ray Dixon

Human intervention has greatly perturbed the global nitrogen cycle, notably through the use of chemical fertilisers in agriculture, resulting in large-scale atmospheric, water and soil pollution, with consequent negative impacts on climate, human health and biodiversity. In Europe alone, the human health and environmental costs of nitrogen pollution are estimated to be €70-320 billion per year. Moreover, since almost 2% of the world’s energy consumption is utilised for fertiliser production and fertiliser costs have doubled over the past year as a result of the energy crisis, there is a pressing need to provide alternative solutions to supply nitrogen to crops.

Biological nitrogen fixation provides a sustainable alternative to the use of synthetic nitrogen fertilisers, particularly in legumes where the symbiotic association with rhizobia can support the nitrogen demands of the plant. However, other crops such as cereals do not engage efficiently with nitrogen-fixing bacteria and it is a considerable challenge to engineer biological nitrogen fixation to satisfy the nitrogen requirements of cereal crops. In this session we will discuss potential approaches for synthetic engineering of nitrogen fixation in order to mitigate the negative impacts of chemical nitrogen fertilisers.