Chunyou 84 is an indica-japonica hybrid rice combination developed from Chunjiang 16A, a late japonica CMS line with early anthesis time, and C84, an indi-ca-japonica intermediate type restorer line with wide compatibility. It has the charac-teristics of high yield potential, high seed production, excel ent agronomic characters, good resistance and wide adaptability. It was registered and released by Zhejiang Provincial Crop Variety Appraisal Committee in March, 2013. The breeding proce-dure, characteristics, major techniques of cultivation and seed production of Chunyou 84 were introduced in this paper.
[Objective] The aim was to select and breed Chunyou 618 which is a novel combination among japonica-indica hybrid rice subspecies. [Method] Chunyou 618 is a japonica-indica hybrid rice combination developed from Chunjiang 16A, a late japonica CMS line with dwarfness and early anthesis time, and C18, an indicaclinous wide compatibility restorer line. In addition, the concerning characters were researched. [Result] Chunyou 618, which is japonica inclining, proved high in pro- duction and in resistance to lodging with Cheng＇s index at 15. It is of moderate re- sistance against Xanthomonas oryzae and stripe virus disease, of moderate susceptibility on rice blast, and of susceptibility on Nilaparvata lugens. The indices of rice quality achieved departmental standard 4 and grade 4 of Cooking Rice Variety Quality, respectively. [Conclusion] Chunyou 618 enjoys strong heterosis, strong stem, good lodging resistance, large panicles, good cold tolerance, high yield and wide adaptability, which is suitable to be grown in Zhejiang Province as single cropping late rice.
