Using precision fermentation to optimize biofertilizer preparation

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Soil fertilization is a key factor for agriculture with nitrogen being the most limiting nutrient for crop productivity. As a critical component for proteins, DNA and chlorophyll, nitrogen is essential for healthy plant growth and development. Half the world's human population currently relies on the Haber-Bosch process to produce synthetic nitrogen fertilizer (SNF). However, 1% of all fossil fuel production is consumed to generate SNF. That cost in CO2 is significant but dwarfed by the second-order effects of the fertilizer, which has only 30-50% efficacy. The remainder enters watercourses as nitrate pollution or is released into the air as nitrous oxide, causing massive environmental damage and human health problems.NetZeroNitrogen (NZN) exists to eliminate synthetic nitrogen fertilizer's estimated 1.1 billion tonnes of CO2e annual contribution to global warming by providing farmers with a highly effective, natural, cheaper alternative to synthetic fertilizer. With a focus on a particularly interesting plant growth-promoting endophytic diazotrophic bacterium with great agronomic potential, our innovation is in building a platform of characterised strain biodiversity to develop highly optimised inoculation formulations for specific crops and environmental conditions. Evaluating the full range of PGP activities (across a library of \>30 strains) has never yet been undertaken anywhere in the world for this bacteria.This project funds the development of a prototype biofertilizer product that will lead to robust, reliable and high levels of colonization of internal tissues in crop plants by the NZN bacteria. Using world-class precision fermentation facilities at the University of Nottingham, the optimization of bacterial cell pre-conditioning for six elite strains will be identified using proprietary colonization assays developed by NZN scientists. Adaptive laboratory evolution, culture media composition and fermentation conditions will then be used to generate enhanced preparations of high-performing strains. The resultant products of fermentation will be tested for their plant growth-promoting performance in rice plants.Once plants are colonized, the bacteria are protected from the external environment meaning they can form season-long symbiotic relationships, and the plants will effectively be able to use the atmospheric nitrogen for their growth and development. Reported to provide 200 kg nitrogen per hectare each year in its host crop - an amount sufficient to satisfy demand in most major intensively-grown cereals - this technology has the potential to impact on a global scale to reduce the world's reliance on environmentally damaging synthetic nitrogen fertilizers.