title: Genetic analysis of ion-beam induced extremely late heading mutants in rice.
abstract: Two extremely late heading mutants were induced by ion beam irradiation in rice cultivar 'Taichung 65': KGM26 and KGM27. The F2 populations from the cross between the two mutants and Taichung 65 showed clear 3 early: 1 late segregation, suggesting control of late heading by a recessive gene. The genes identified in KGM26 and KGM27 were respectively designated as FLT1 and FLT2. The two genes were mapped using the crosses between the two mutants and an Indica cultivar 'Kasalath'. FLT1 was located on the distal end of the short arm of chromosome 8. FLT2 was located around the centromere of chromosome 9. FLT1 might share the same locus as EHD3 because their chromosomal location is overlapping. FLT2 is inferred to be a new gene because no gene with a comparable effect to that of this gene was mapped near the centromere of chromosome 9. In crosses with Kasalath, homozygotes of late heading mutant genes showed a large variation of days to heading, suggesting that other genes affected late heading mutant genes.
authors.affiliation: Faculty of Agriculture, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Ichitani
authors.affiliation: Faculty of Agriculture, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamaguchi
authors.affiliation: Institute of Gene Research, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Taura
authors.affiliation: Radioisotope Center, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Fukutoku
authors.affiliation: Faculty of Agriculture, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Masahira
authors.initials: M
authors.lastname: Onoue
authors.affiliation: Faculty of Agriculture, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Shimizu
authors.affiliation: Faculty of Agriculture, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Hashimoto
authors.affiliation: Faculty of Agriculture, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sakata
authors.affiliation: Faculty of Agriculture, Kagoshima University , 1-21-24 Korimoto, Kagoshima, Kagoshima 890-0065 , Japan.
authors.forename: Muneharu
authors.initials: M
authors.lastname: Sato
keywords: days to heading; ion beam; late flowering; linkage analysis; mutation