As sea levels rise as a result of climate change, more and more places around the world are struggling with seawater inundation - where salt water from the sea is flooding further inland and destroying crops which can’t cope with the increased salinity.
Rice is one of the worst affected crops - the most important carbohydrate on earth, it is relied on by 3.5 billion people every day, but in countries like Vietnam it is becoming harder and harder to grow due to increasing seawater interference.
However, findings from the University of Sheffield’s Institute for Sustainable Food have revealed that genetically modifying rice to reduce the number of stomata is has - tiny openings used for water loss - makes it more salt-resistant.
Stomata are openings that most plants have which regulate carbon dioxide uptake for photosynthesis, along with the release of water vapour. Several years ago, Sheffield scientists revealed that reducing the number and size of stomata rice plants that have allows them to use up to 60 per cent less water, making them hugely beneficial in places prone to drought.
Those findings, along with these new results, published in the New Phytologist, mean that rice can be adapted to survive in environments that are becoming harsher due to climate change, which will help in tackling food insecurity around the globe.
The researchers also discovered, however, that reducing the number and size of stomata could make rice harder to grow in extremely hot temperatures. As a result, to make sure that rice can grow as effectively as possible in different countries and environments, different modifications will need to be made. For example - rice with fewer, larger stomata, could be better suited to growing in extremely warm temperatures.
Dr Robert Caine, Lead Author of the study from the University of Sheffield’s School of Biosciences, said: “Rice is a hugely important food crop eaten by over half the world's population on a daily basis. Ensuring that it can survive in harsher conditions caused by climate change will be integral to feeding a growing population that is projected to reach 10 billion in 60 years’ time.
“Our findings reveal how rice can be modified to grow as effectively as possible in different climates - varieties of rice that have less stomata can survive with less water and in places with salt water. Meanwhile, natural rice varieties with fewer, bigger stomata are able to thrive in hotter temperatures.”
The researchers from the University of Sheffield, working alongside the High Agricultural Technology Research Institute (HATRI) in Vietnam, studied 72 rice varieties, both natural and genetically modified. They are now planning to investigate whether they can make dwarf rice varieties, which produce the highest crop yields, more heat-resistant.
Dr Caine stressed that unlike other more traditional genetically modified crops, the rice varieties examined in the study did not incorporate genes from other organisms.
"To produce rice with fewer stomata, we used a gene that is already present in rice,” he explained to FoodNavigator. “We overexpressed the gene (EPF1) using a genetic construct that also has genes from other organisms. The additional genes are used for enabling researchers to find the rice plants that have been transformed. This is how we screen for transformed plants.”
He therefore does not expect any ‘Frankenfood’ commotion as a result of the study, he told us. “Our research is more about proof of concept at this stage. We (as well as others) are moving towards gene editing technology in the future which will enable researchers to alter crops without leaving any foreign DNA in the plant by the time the process is completed. That is, we can breed out any remnants of the gene editing process except the change we are making in the DNA sequence.”
Will people be convinced to eat it? “I think if we can increase plant productivity and maintain the nutritional properties of our crops, then people will be open to the idea of GM or gene edited crops.”
Reference
Genetically modified rice could be key to tackling food shortages caused by climate change
New Phytologist
DOI: 10.1111/nph.18704