title: Cloning of quantitative trait genes from rice reveals conservation and divergence of photoperiod flowering pathways in Arabidopsis and rice.
abstract: Flowering time in rice (Oryza sativa L.) is determined primarily by daylength (photoperiod), and natural variation in flowering time is due to quantitative trait loci involved in photoperiodic flowering. To date, genetic analysis of natural variants in rice flowering time has resulted in the positional cloning of at least 12 quantitative trait genes (QTGs), including our recently cloned QTGs, Hd17, and Hd16. The QTGs have been assigned to specific photoperiodic flowering pathways. Among them, 9 have homologs in the Arabidopsis genome, whereas it was evident that there are differences in the pathways between rice and Arabidopsis, such that the rice Ghd7-Ehd1-Hd3a/RFT1 pathway modulated by Hd16 is not present in Arabidopsis. In this review, we describe QTGs underlying natural variation in rice flowering time. Additionally, we discuss the implications of the variation in adaptive divergence and its importance in rice breeding.
authors.affiliation: NARO Institute of Crop Science Tsukuba, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Matsubara
authors.affiliation: Agrogenomics Research Center, National Institute of Agrobiological Sciences Tsukuba, Japan.
authors.forename: Kiyosumi
authors.initials: K
authors.lastname: Hori
authors.affiliation: Agrogenomics Research Center, National Institute of Agrobiological Sciences Tsukuba, Japan.
authors.forename: Eri
authors.initials: E
authors.lastname: Ogiso-Tanaka
authors.affiliation: NARO Institute of Crop Science Tsukuba, Japan ; Agrogenomics Research Center, National Institute of Agrobiological Sciences Tsukuba, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yano
keywords: breeding; natural variation; photoperiodic flowering; quantitative trait gene; rice