title: Genetic analysis and fine mapping of a novel semidominant dwarfing gene LB4D in rice.
abstract: A dwarf mutant, designated LB4D, was obtained among the progeny of backcrosses to a wild rice introgression line. Genetic analysis of LB4D indicated that the dwarf phenotype was controlled by a single semidominant dwarfing gene, which was named LB4D. The mutants were categorized as dn-type dwarf mutants according to the pattern of internode reduction. In addition, gibberellin (GA) response tests showed that LB4D plants were neither deficient nor insensitive to GA. This study found that tiller formation by LB4D plants was decreased by 40% compared with the wild type, in contrast to other dominant dwarf mutants that have been identified, indicating that a different dwarfing mechanism might be involved in the LB4D dominant mutant. The reduction of plant height in F(1) plants ranged from 27.9% to 38.1% in different genetic backgrounds, showing that LB4D exerted a stronger dominant dwarfing effect. Using large F(2) and F(3) populations derived from a cross between heterozygous LB4D and the japonica cultivar Nipponbare, the LB4D gene was localized to a 46 kb region between the markers Indel 4 and Indel G on the short arm of chromosome 11, and four predicted genes were identified as candidates in the target region.
authors.affiliation: State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liang
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Xin
authors.forename: Zejun
authors.initials: Z
authors.lastname: Hu
authors.forename: Jiandi
authors.initials: J
authors.lastname: Xu
authors.forename: Gang
authors.initials: G
authors.lastname: Wei
authors.forename: Xiaoyin
authors.initials: X
authors.lastname: Qian
authors.forename: Jinshui
authors.initials: J
authors.lastname: Yang
authors.forename: Haohua
authors.initials: H
authors.lastname: He
authors.forename: Xiaojin
authors.initials: X
authors.lastname: Luo
mesh_terms: D020029:Base Pairing / Q000235:genetics; D002681:China; D003433:Crosses, Genetic; D004790:Enzyme Induction / Q000187:drug effects; D005799:Genes, Dominant / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics*; D005819:Genetic Markers; D005838:Genotype; D005875:Gibberellins / Q000494:pharmacology; D006579:Heterozygote; D006720:Homozygote; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000166:cytology / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development*; D010641:Phenotype; D020161:Physical Chromosome Mapping / Q000379:methods*; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011995:Recombination, Genetic / Q000187:drug effects; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology; D000516:alpha-Amylases / Q000096:biosynthesis
chemical_list: D005819:Genetic Markers; D005875:Gibberellins; D010940:Plant Proteins; D000516:alpha-Amylases