Ratoon rice becomes a technical reserve for safeguarding food security

Years of practice have shown that ratoon rice is a resource-saving and highly efficient rice cropping system, conducive to raising the comprehensive production capacity of paddy fields and increasing the multiple cropping index of paddy fields. In recent years, Youxi County, Fujian Province, has planted nearly 100,000 mu of ratoon rice annually, with an average main crop yield of 600 kg per mu and an average ratoon season yield of 300 kg per mu. Since 2000, the Fuzhou National Rice Improvement Sub-center of the Fujian Academy of Agricultural Sciences has continuously achieved, in a hundred-mu ratoon rice demonstration plot, an average main crop yield of 838 kg per mu and an average ratoon season yield of 488.4 kg per mu; in a thousand-mu demonstration plot, an average main crop yield of 723.9 kg per mu and an average ratoon season yield of 414.1 kg per mu; and in 100,000 mu of ratoon rice, an average main crop yield of 605.9 kg per mu and an average ratoon season yield of 297.8 kg per mu. The rice-growing region of southern China has 200 million mu of single-season paddy fields, of which 50 million mu of single-season paddy fields (where temperature and light resources are more than sufficient for one season but insufficient for two) are suitable for planting ratoon rice. If the yield level of Youxi County, Fujian Province, could be reached, rice output could increase by 20 million tons per year. Developing ratoon rice is a major technical reserve for ensuring China's future food security.

In the future, we will, through multi-year and multi-site screening of new super rice varieties with strong ratooning ability, the physiological basis of high ratoon yield in super rice, and cooperation with the Chinese Academy of Sciences, carry out research on the photosynthetic physiology of high ratoon yield in ratoon rice, including the photo-oxidation physiological characteristics of the ratoon season; research on the transport and transformation mechanisms of C and N elements for high ratoon yield in super rice, the interaction network regulation of genes for high ratoon yield, and, through genetic analysis, clone genes related to strong ratooning ability and analyze the molecular mechanisms of these genes; the root development characteristics of high ratoon yield in super rice, the morphological structure and developmental characteristics of ratoon axillary bud growth and development and the expression characteristics of related genes, and the molecular biological and physiological basis of high yield; analyze the molecular mechanisms of high ratoon yield in super rice as well as the coordination of sink, source and flow and the physiological basis of high-yield cultivation, so as to lay the foundation for analyzing the molecular biological basis of high ratoon yield in super rice and for further promoting and applying ratoon rice, and to provide technical support for solving the national food security issue.