Abstract: China’s super rice research project was initiated by the Ministry of Agriculture in 1996. In the past 20 years, China has been a leader in super rice research, including genetic and physiological basis of super-high yielding or theory and practice for super rice breeding, and indica super hybrid rice in south or conventional japonica super rice in north. These research provided scientific and technical basis for improving production potential and converting sciences and technology to realistic productivity, and made outstanding contribution for maintaining China the international advanced level on rice science. Research progress of japonica super rice in Northern China, including the development of super rice, establishment of technical route, new variety breeding and demonstration promotion, basic research in physiological and genetic were reviewed in this paper. Meanwhile, some related physiological and genetic issues of Northern japonica super rice were discussed: The Northern japonica rice in recent years kept high levels on yield and quality, and the chalk white character and other appearance qualities have been improved, without significant contradiction between yield and main quality traits when yield no more than 9 t·hm^-2, and the yield and quality can reach a new balance at a higher level. Analysis of Northern japonica rice regional test results showed that extending growth period to increase yield was unsatisfactory, also not work by increasing plant height, while improving the resistance to rice blast was one of the important breeding targets for Northern japonica rice. The seed density of Northern japonica rice is generally high, but the negative impact on the yield components and the main quality traits is relatively small, which can be thought that Northern japonica rice seed density is in an appropriate range through the untiring efforts of the breeders. Grain length-width ratio is a main factor determining indica and japonica rice milling quality, and less impact on the appearance quality difference between subspecies. Chinese indica rice milling quality has been improved significantly in recent years, difference between indica and japonica rice decreases. The appearance quality of indica and japonica rice has improved significantly, but the difference still exists between indica and japonica. On the basis of full summarizing Chinese super rice research achievements and experience in the past 20 years, the super rice research directions and goals in the future should be determined. Long-term stability research support mechanism according to the ecological regions should be established instead of stage yielding goals; small area yield evaluation should be changed to the assessment of large area stable yield increase. The basic theory and key technology research should be targeted according to the ecology, production and varieties of Northern japonica rice, such as the genetic and physiological and ecological mechanism of indica and japonica yield and quality. From the molecules, cells, tissues, organs, individual and population levels, comprehensive evaluation of erect panicle gene EP1 function should be further studied to effectively improve quality of both indica and japonica hybrid varieties with big and erect panicles. We should make full use of the research achievements of molecular biology and technology, and make a breakthrough on rice blast resistance, cold resistance and salt-tolerant germplasm innovation and breeding.

Key words: China, rice, japonica super rice, breeding of super-high yielding