The increasing concentration of greenhouse gases (GHGs) in Earth’s atmospheric leads to global warming, which draw global attentions. CH₄ emissions from rice paddies, is one major source of agricultural GHGs, which contributes ~2.40% to the enhanced global warming effect. It is necessary to free rice cultivation from logged water to reduce the CH₄ emissions for the carbon neutrality, which was named rice “blue revolution”.

Recently, scientists from Shanghai Agrobiological Gene Center have published an Opinion in Molecular Plant (IF: 21.949) to introduce their efforts in rice “blue revolution” by developing water-saving and drought-resistance rice (WDR). WDR possesses the high WUE and good drought resistance from upland rice, which makes it suitable for aerobic cultivation with less water and fertilizer. It also possesses the good quality and high yield which are equivalent to the elite paddy rice.

In the last two decades, 22 WDR varieties have been developed and granted national and/or local certifications after rigorous field tests, which covers more than two-thirds of the provinces in China. WDR can be directly seeded and planted like wheat. Farmers can obtain a satisfactory yield (~9.0 tons per hectare) from WDR under diverse water-saving cultivation modes and experience extra benefits from the saved resources and labors. The annual planting area of WDR has been expanded to ~200,000 hectares in China. WDR also has been tested in >20 African and Asian developing countries and earned an excellent worldwide reputation.

Figure 1 WDR in China and world.

Planting WDR following rainfed dry-farming has great environmental benefits by reducing GHG emissions without apparent yield loss. In a recent two-year field experiment (2019-2020), the cultivation of Hanyou73 in aerobic cultivation reduced CH₄ emissions by 97.2% (90.71~99.69%) in Anhui Province compared with common paddy rice varieties. In next five years, we aim to reduce 156,100 tons of CH₄ emission annually reduction by planting WDR, which can provide an extra benefit of up to $43.7 million for farmers once the reduced Carbon Dioxide Equivalent can be exchanged in the market.

Figure 2. Field test of CH4 in WDR and paddy field. (It is conducted by Eco‑Environmental Protection Research Institute, Shanghai Academy of Agricultural Sciences.)

WDR is triggering the rice “blue revolution” in China, which frees rice cultivation from irrigation, labor-intensive practices, and GHG emissions. The GSR variety and its environment-friendly cultivation, as represented by WDR, will replace the conventional cultivation of paddy rice with a rebuilt balance between productivity and GHGs emission. This innovation in rice germplasm can make significant contributions to the food security and mitigation of global warming.