Photosynthesis breakthrough crams millions of years of plant evolution into months

Scientists have improved "the most important biological process on the planet" - photosynthesis.

The breakthrough, published in the journal Science, used genetic modification to increase the amount of sunlight crops convert into food by 15%. That's a whopping amount - the equivalent to 100 million years worth of evolution crammed into just a few months.

The researchers, from  the University of Illinois, University of California Berkeley and the University of Lancaster, lead by Professor Stephen Long say this is a critical step towards increasing crop production to feed a growing global population and attributed the breakthrough to decades of research into the 140 step photosynthesis process where plants convert sunlight energy into food. And it's this research that helped the team find specific "inefficiencies in crops".

"There are bottlenecks holding up the conversion of sunlight energy into food," said Long, "our research has tackled one of those bottlenecks."

 

The scientists targeted a plant's natural Sun protection mechanism - while plants have evolved to produce food using sunlight energy, they have also evolved to protect themselves from Sun damage, which slows the process down.

"To protect itself, the leaf induces a process that gets rid of excess energy as heat," said Long, "but the problem is when a cloud moves across the Sun, there's less sunlight energy - the plant could use it all, but it carries on dispensing that energy as heat. So what we've done is speed up the process that turns that heat loss off faster."

The team did it by inserting extra copies of the genes responsible for this "heat-loss switch" into Tobacco lab plants and when they then grew their genetically modified crop, it grew 15% larger than normal.

"This is a big jump," said Long, "well, we're now making this change in rice, in soy bean and wheat; 15% in those would be huge. Globally rice, wheat, maize and soybean are the biggest crops. So if we could get the same increase in those, that would greatly alleviate what we see as the future pressure on food supply."

That pressure will intensify in the coming few decades, according to the United Nations Food and Agriculture Organisation (UNFAO).

“The United Nations predicts that by 2050 we’re going to need to produce about 70 percent more food on the land we’re currently using,” Long said, “my attitude is that it is very important to have these new technologies on the shelf now because it can take 20 years before such inventions can reach farmer’s fields. If we don’t do it now, we won’t have this solution when we need it."

"At the current rate we're not going to come close to reaching that target, so we're really in desperate need of new innovations," said Long, "so for us in the West food prices will go up, but for some of the poorest nations, many households are already spending almost 100% of their household income on food, so for those families and those countries, this will be a catastrophe."

"This is great news but it's just one change, and we don't yet know if these plants will require more of other resources like water. It's really important to increase crop yields significantly, but also sustainably," said Dr Hans Dreyer, from the UNFAO's of the plant production and protection division.

Meanwhile Prof Christine Foyer, who directs a food security project for Sub-Saharan Africa at the the University of Leeds, described the breakthrough as "vital".

"In terms of making Africa green and solving the problems associated with agriculture in those parts of the world improving the processes involved in photosynthesis is an important step in solving food security. Many people in the world today don't get enough to eat. And it's possible to envisage, with these new developments, that we can achieve zero hunger within the next 20 years," she said.

The Bill and Melinda Gates Foundation funded the research, with the stipulation that any new agricultural products that result from the work be licensed in such a way that the technology is freely available to farmers in poor countries of Africa and South Asia.