Researchers at the University of Illinois have found a way to modify photosynthesis in plants in order to increase their food production considerably.
In a study featured in the journal Science, plant biology professor Stephen Long and his colleagues were able to improve crop yields by as much as 14 to 20 percent by tweaking how plants get nourishment from the sun.
Nonphotochemical Quenching
While some scientists have long suspected that modifying photosynthesis can help boost a plant's ability to produce crops, others have doubted if this was even doable.
Long and his team sought to prove that this hypothesis was possible by conducting various computational analysis and experiments in the laboratory and field. After years of hard work, they were able to identify certain proteins that can help boost crop production.
For their study, the researchers chose to use tobacco as it is a plant that can easily be modified. They then targeted a natural process that allows plants to protect themselves from getting exposed to too much solar energy.
According to Long, crop leaves that receive full sunlight are able to absorb more light than they can actually use. If the plant isn't able to get rid of this excessive amount of energy, it will result in leaf bleaching.
To help protect themselves from too much solar energy, plants make use of a process known as nonphotochemical quenching. This is when plants make certain modifications within their leaves to help scatter excess energy in the form of heat.
However, this process can be severely limited if clouds happen to block the sun or if the leaves go into the shade of another plant. It could take as long as half an hour for the plant's NPQ to relax.
Long explained that the lack of light exposure restricts the plant's ability for photosynthesis. It also loses whatever light it has already accumulated because of NPQ.
Through the use of computer analysis, the researchers were able to determine how much the slowdown of NPQ affects a plant's crop production throughout an entire day.
Their calculations showed that as much as 7.5 to 30 percent of crop productivity is reduced whenever NPQ is slowed down, depending on the type of plant involved and the temperature it is exposed to.
Krishna Niyogi, a researcher at UC Berkeley and an expert on the NPQ process at a molecular level, helped Long and his team to identify three proteins capable of improving a plant's recovery process.
Increased Crop Production
The researchers used three genes taken from an Arabidopsis plant and then inserted them into their tobacco model to help boost its existing proteins. This allowed them to produce engineered seedlings that have varied responses to light changes.
Long and his colleagues chose three of the best performing seeds and then had them tested in the field alongside unmodified tobacco plants.
They discovered that two of the altered plants yielded 20 percent more crops compared with the unchanged tobacco. The third modified crop, on the other hand, showed a 14 percent higher crop production.
The study showed an increase in the tobacco's leaves. However, the researchers believe that if food crops were to be used, it would result in a similar boost in production in terms of the parts of the plant that are eaten, such as roots, seeds or fruits.
Long and his team are now working to replicate their findings using other food crops. With the United Nations calling for a 70 percent increase in food production by 2050 in order to sufficiently feed the world's populations, the University of Illinois study could very well hold the key to the situation.
