Harnessing key traits in rice breeding to reduce greenhouse-gas emissions

Rice is often referred to as the ‘prince of cereals’, because it sustains two-thirds of the world’s population. However, the increasing concentration of greenhouse gases (e.g. CO2 and CH4) in the atmosphere is projected to raise Earth’s temperature by an estimated 2.5–4.5°C by the end of the 21st century. The cultivation of rice is one of the major contributors to greenhouse-gas emissions from the agricultural sector. It will thus accelerate global warming. Numerous investigations have demonstrated that temperature increases of merely 1°C result in a 5–10% decrease in yield. Various studies have suggested that characteristics such as short duration, effective resource use, root-related traits, and ratooning ability will lead to lower greenhouse-gas emissions. This review summarizes the findings on reducing greenhouse-gas emissions in rice cultivation from a breeding perspective. It suggests that future breeding programs should focus on combining the identified traits to help develop climate-smart, environmentally sustainable cultivars that can reduce greenhouse-gas emissions without compromising yield and quality.