title: Genetic analysis of two weak dormancy mutants derived from strong seed dormancy wild type rice N22 (Oryza sativa).
abstract: Two weak dormancy mutants, designated Q4359 and Q4646, were obtained from the rice cultivar N22 after treatment with 400 Gy (60) Co gamma-radiation. Compared to the N22 cultivar, the dormancy of the mutant seeds was more readily broken when exposed to a period of room temperature storage. The mutants also showed a reduced level of sensitivity to abscisic acid compared to the N22 cultivar, although Q4359 was more insensitive than Q4646. A genetic analysis indicated that in both mutants, the reduced dormancy trait was caused by a single recessive allele of a nuclear gene, but that the mutated locus was different in each case. The results of quantitative trait locus (QTL) mapping, based on the F(2) population from Q4359 x Nanjing35, suggested that Q4359 lacks the QTL qSdn-1 and carries a novel allele at QTL qSdn-9, while a similar analysis of the Q4646 x Nanjing35 F(2) population suggested that Q4646 lacks QTL qSdn-5, both qSdn-1 and qSdn-5 are major effect seed dormancy QTL in N22. Therefore, these two mutants were helpful to understand the mechanism of seed dormancy in N22.
authors.affiliation: National Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, China.
authors.forename: Bingyue
authors.initials: B
authors.lastname: Lu
authors.forename: Kun
authors.initials: K
authors.lastname: Xie
authors.forename: Chunyan
authors.initials: C
authors.lastname: Yang
authors.forename: Long
authors.initials: L
authors.lastname: Zhang
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
authors.forename: Xi
authors.initials: X
authors.lastname: Liu
authors.forename: Ling
authors.initials: L
authors.lastname: Jiang
authors.forename: Jianmin
authors.initials: J
authors.lastname: Wan
mesh_terms: D000040:Abscisic Acid / Q000502:physiology; D005720:Gamma Rays; D018525:Germination; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000254:growth & development; D010641:Phenotype; D057445:Plant Dormancy / Q000235:genetics*; D040641:Quantitative Trait Loci
chemical_list: D000040:Abscisic Acid