The breeding of a rice xantha leaf marker CMS line by gamma rays mutation

A rice mutant WYB, which exhibited xantha leaf during whole growing period, was isolated from II-32B with gamma ray irradiation. The novel CMS line and its maintainer line with the xantha leaf marker, Huangyu A(B), were developed after a series of backcrosses, and were appraised by the Department of Science and Technology, Zhejiang Province. It Suggested that the Huangyu A(B) showed visible xantha leaf marker and different agronomic characteristics, such as lower plant height, smaller panicle, lighter grain weight, lower yield per plant etc. Genetical analysis demonstrated that the xantha leaf mutation was controlled by a single recessive locus, the xantha leaf color was stable at different environment. The leaf mutant had not negative affect on its hybrid offspring. However, the Huangyu A showed higher combining ability. The novel combination Huangyou C23 (Huangyu A/Chihui 23) harvested the highest yield at Jinhua hybrid rice regional test, showed high potential in rice production. By use of the xantha leaf marker, the varietal purity of Huangyu A and its hybrids could be easily and quickly identified at seedling stage. And the purity results were highly consistent with that evaluated in field plot testing at maturity period according to national standard GB/T 3543.5-1995. (authors)