In 2021 one in ten of the global population suffered starvation for a substantial portion of the year, a number that has been rising steadily since 2014.

Many of those afflicted are small-holder farmers and their families in the Global South. The Food and Agriculture Organization of the United Nations (UN-FAO) project a worsening situation with global demand for our major crops rising 60% by 2050.

In the last Century the Green Revolution addressed this by providing farmers with seed with greater genetic yield potential and agronomy to realise that potential. However, the steady increases in yield seen over the second half of the last century are now stagnating, or even reversing, under global climate change. In part, this is because the approaches of the Green Revolution are reaching their biological limits, and new innovations are urgently needed if we are to insure against future shortages.

In this talk Dr Steve Long, Ikenberry University Chair of Plant Biology, University of Illinois, will suggest that improvement of photosynthetic efficiency is the largest remaining opportunity to increase genetic crop yield potential. Photosynthetic efficiency in crops falls well below the theoretical maximum, suggesting considerable head-room for improvement, yet has been improved little by centuries of selection and breeding; the reasons for which will be explained.

Today photosynthesis is the best understood of all plant processes, allowing us to describe each of its 100+ steps mathematically in a digital twin of the actual process. Using this with high-performance computing we identified a number of points at different levels of organisation from gene expression and metabolism to organisation of leaves in field crops where efficiency could be improved. This includes both adaptation to rising temperature and changing water availability. Bioengineering is now validating a number of these suggested improvements with substantially greater crop productivity demonstrated in replicated field trials.

Our analyses suggest that such engineering could lead to a >50% sustainable improvement in crop yield potential so providing insurance against future food shortage and avoiding yet further agricultural expansion and associated destruction of natural areas. These innovations will have greatest value in seed for the small-holder farmers of the Global South, but could also reduce the agriculutral footprint of food crops elsewhere.

More productive future-proofed crops via manipulation of photosynthesis to address global food security in 2050