Breeding And Application Of Jinyou 431, A High-yielding Hybrid Rice Combination With Cold Tolerance

The yield of hybrid rice is higher than that of conventional varieties obviously.The large scale extension of hybrid contributes to foodstuff safety of out country.The yield is reduced for some non-cold tolerance hybrid rice when the cold weather occurs and low temperature damage happen in rice heading stage..The cold tolerance restore line Q431 and its combination Jinyou 431 were bred by Mr.Hongjun Tang and his colleagues through many years efforts.It was conduced to the researches in the breeding of restore line Q431 and hybrid Jinyou 431, their cold tolerance,the combining ability of restore line Q431 and the cultivating technologies of hybrid Jinyou 431.The main results is:1.In order to solve the problem that the Hybrid Rice hasn't the cold resistance.The restore-lines of cold resistance were bred with the way using restorer-lines of the WA type cytoplasm and the karyon from cold resistance genes of Guizhou native japonica rice variety Hezhang Xiaohuanggu through several times breeding and collection.The restorer lines Q431 was the stronger combining capacity,the wide restorer spectrum,the higher cold resistance stamclard and the better capacity of resistance rice blast in these cold resistance restore-lines. The hybrid Jinyou431,a combination between Q431 and Jin 23 A,has better cold resistance, and the larger production potentiality.2.The average yield of hybrid Jinyou 431 yield is 591.9kg/667 m~2 in two years and 16 places and was 15.2%over CK Shanyou 64 in the Provincial Hybrid Trial.The grain quality of Jinyou431 reached the No.2 grade of the standards for the high quality rice of the agricultural ministry of China.It was resistant to rice sheath blight with the GPA 3.1 degree and obviously better than CK Jinyou 207.3.It was better chilling tolerance to the restorer line Q431 and hybrid Jinyou 43 in shoot stage tests.It was the first grade chilling tolerance(HR) to restorer line Q431 and third(R) grade chilling tolerance to the hybrid Jinyou431 in seedling stage tests.It was obviously better than the restorer line Minhui63 and hybrid Shanyou63.So Jinyou431 played important role in Guizhou.4.There were better general combining-ability with yield,seeding setting and the effective panicle number of the restorer line Q431 in the cross tests of 5 restorer lines and 8 sterile lines.5.It was formulated for logical layout,cultivating strong seedling,appropriate planting thick,scientific fertilization and attention for middle and late stage for high-yielding cultivation techniques to the high yield cultivating technologies of hybrid Jinyou 431.It was also formulated for making suitable planting stag between male and female,cultivating strong seedling and appropriate planting density and setting high-yield composition and using gibberellins rationally to the high-yielding seed production techniques.