Breeding for water-saving and drought-resistance rice (WDR) in China

Rice is the staple food and rice production consumes about 50% of the fresh water resources in China. In addition, drought is one of the most important constraints in rice resulting in large yield losses and limiting the average yield increase of the country. There is an urgent need to enhance water-saving (W) capacity or drought resistance (DR) of rice. WDR varieties can be developed through introgressing the water-saving and drought resistance capacity mainly from the traditional upland to the commercialized paddy rice cultivars. The breeding target is a high yield potential under irrigation, an acceptable grain quality, and water consumption reduced by about 50% compared with paddy rice. In a water-limited environment, a higher level of drought resistance and reduced yield loss by drought stress are required. In recent years, the field drought-resistance screening facility was established and the evaluation standard was developed. Some DR rice varieties were identified and used in both molecular mapping and breeding programmes. Several WDR varieties were developed and released to farmers. This article describes our initial achievement towards this goal and provides some details on the rationale and the specific steps and methods used.