Methane forming microorganisms that thrive in the oxygen-poor environment surrounding rice roots converts root exudates into methane. Atmospheric methane is the second most important greenhouse gas after CO2, and is responsible for about 20% of the global warming effect since pre-industrial times.
Now the researchers have succeeded in reducing the amount of methane emitted by changing how much carbon that is allocated to the root system in relation to the amount of carbon allocated to leaves and inflorescences. By adding a gene from barley that affects starch storage, the rice plants allocate more starch to the parts above ground as compared to the root. This is believed to provide a reduced leakage of carbon compounds to the surrounding soil, which in turn results in reduced methane emission.
This is an example of how modern plant breeding can help to reduce the environmental impact of agriculture and at the same time increase food production. The findings are published in the coming issue of the scientific journal Nature.