| (Yangzhou University, Yangzhou, Jiangsu Province, P.R. China, 225009) At present, more than 70 semidwarf or dwarf genes have been identified, but most of these semidwarf or dwarf genes have impractical pleiotropic phenotypes and exert unfavorable effects on many agronomic characters therefore restricting their use in cross breeding. Conventional genetic analysis reveales that all of the semidwarf genes in cultivars are controlled by an allele at the sd1 locus. The frequent use of the single semidwarf gene might cause genetic vulnerability to pests and diseases. Therefore, it is essential to develop an alternative or new source of semidwarf genes to broaden the genetic basis of the semidwarfism.. In this study, we described the identification, characterization, fine mapping of onenew rice semidwarf gene sdt3 and fine mapping, cloning and functional analysis of the other semidwarf gene sdg, The main results were as follows:1.A marker line material Duonieai(DA)used in the study was a dwarf mutant , however genetic analysis showed that its dwarf trait was controlled by two recessive semidwarf genes, sd1 and a new semidwarf gene sdt3.A F2 segregating population... |
