title: Mapping and characterization of seed dormancy QTLs using chromosome segment substitution lines in rice.
abstract: Seed dormancy--the temporary failure of a viable seed to germinate under favorable conditions--is a complex characteristic influenced by many genes and environmental factors. To detect the genetic factors associated with seed dormancy in rice, we conducted a QTL analysis using chromosome segment substitution lines (CSSLs) derived from a cross between Nona Bokra (strong dormancy) and Koshihikari (weak dormancy). Comparison of the levels of seed dormancy of the CSSLs and their recurrent parent Koshihikari revealed that two chromosomal regions-on the short arms of chromosomes 1 and 6-were involved in the variation in seed dormancy. Further genetic analyses using an F(2) population derived from crosses between the CSSLs and Koshihikari confirmed the allelic differences and the chromosomal locations of three putative QTLs: Sdr6 on chromosome 1 and Sdr9 and Sdr10 on chromosome 6. The Nona Bokra alleles of the three QTLs were associated with decreased germination rate. We discuss the physiological features of the CSSLs and speculate on the possible mechanisms of dormancy in light of the newly detected QTLs.
authors: University of Tsukuba, 1-1-1 Tennohdai, Tsukuba, Japan.
authors: Salem
authors: S
authors: Marzougui
authors: Kazuhiko
authors: K
authors: Sugimoto
authors: Utako
authors: U
authors: Yamanouchi
authors: Masaki
authors: M
authors: Shimono
authors: Tomoki
authors: T
authors: Hoshino
authors: Kiyosumi
authors: K
authors: Hori
authors: Masatomo
authors: M
authors: Kobayashi
authors: Kanako
authors: K
authors: Ishiyama
authors: Masahiro
authors: M
authors: Yano
mesh_terms: D002874:Chromosome Mapping; D003433:Crosses, Genetic; D017931:DNA Primers / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics; D012275:Oryza / Q000235:genetics*; D057445:Plant Dormancy / Q000235:genetics* / Q000502:physiology; D040641:Quantitative Trait Loci / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D017931:DNA Primers