Rice is a staple food eaten by more than half the world’s population every day. People in developing countries are particularly reliant on rice for food security and income generation but rice cultivation is very water intensive. Almost half of the global rice crop derives from rain-fed agricultural systems where drought and high temperatures are predicted to become more frequent and damaging under climate change.
Scientists from the UK and the Philippines have discovered that rice plants genetically engineered to have fewer stomata – tiny openings used for gas exchange – are more tolerant to drought and resilient to future climate change.
Like most plants, rice uses microscopic pores called stomata to regulate carbon dioxide uptake for photosynthesis, along with the release of water vapour via transpiration. When water is plentiful, stomatal opening also permits regulation of plant temperature by evaporative cooling. Under drought conditions the stomata close, slowing down water loss. Rice with a lower density of stomata conserves water better under drought, and so has more water left to cool itself when necessary.
Researchers found that rice lines with fewer stomata used just 60 percent of the normal amount of water. When grown at elevated atmospheric carbon dioxide levels, these rice plants were able to survive drought and high temperature (40 degrees Celsius) for longer than unaltered plants. The findings could have implications for rice production in other regions and the research team now hope to investigate how the rice plants cope with other environmental stresses.
"We found that the engineered rice crops gave equivalent or even improved yields, which means it could have a massive impact on our future food security which is threatened by climate change"
Dr Robert Caine, Research Associate at the University of Sheffield’s Department of Molecular Biology and Biotechnology
Climate ready rice: Optimising transpiration to protect rice yields under abiotic stresses
Project leads: Professor Julie Gray, Department of Molecular Biology and Biotechnology at the University of Sheffield, UK, Dr Apichart Vanavichit, Rice Gene Discovery Unit at Kasetsart University, Bangkok, Thailand and Professor W. Paul Quick, International Rice Research Institute, Philippines
Delivery Partners: Biotechnology and Biological Sciences Research Council, the National Science and Technology Development Agency, Thailand, the International Rice Research Institute, Philippines, the Rice Biotechnology Research Institute of Chinese Academy of Agricultural Sciences, and the Science Center at Kasetsart University in Thailand