Two independent grain-length mutants mapped to a single region on the long arm of chromosome 2 in rice

ABSTRACT Grain shape in rice is a key determinant of grain appearance, yield and market value, and thus has been widely studied. Rice mutant lines with long-grain phenotypes were previously isolated from an M2 population derived from mutagenized mature pollen grains that were treated with gamma-ray irradiation for a cultivar Ma85. To understand the genetic basis underlying the long-grain trait, two mutant lines, JF171 and JF178, were crossed with the short-grain parents JF222 and Samba, generating three F2 populations. Molecular marker-based genetic analysis was employed to detect the major QT...