CENETIC ANALYSIS OF A RICE MUTANT IPD1AND FINE MAPPING OF THE DWARF GENE IPD1

Dwarf mutants in plant were crucial for elucidating regulating mechanisms underlying plant growth and development.A spontaneous dwarf mutant in this study was identified from an indica cuhivar 3037.This dwarf mutant not only had short and stout stem,but also had one more internode with short,thick and dark greenleaves. We tentatively designated the dwarf mutant as ipd1(internode plethora dwarf 1).Genetic analysis showed that the phenotype of ipdl was controlled by a single recessive gene.Physiological analysis demonstrated that the mutant might be caused by deficiency in GA biosynthesis.To determine the function of IPD1,we tried to isolate IPD1 by map-based cloning approach,1,052 F_2 segregants were used for fine mapping,and IPD1 was finally delimited to a 100 kb region on the short arm of chromosome 3.This work provided an important basis for finally cloning of IPD1 gene.