title: Both Hd1 and Ehd1 are important for artificial selection of flowering time in cultivated rice.
abstract: Rice is a facultative short-day plant, and it requires a photoperiod shorter than the critical day length to get flowering. Sensitivity to photoperiod has been suggested as a major selection target in cultivated or weedy rice. The modern rice varieties in Taiwan may be cultivated twice a year. These varieties contain loss-of-function of two important flowering-time related genes, Heading date 1 (Hd1) and Early heading date 1 (Ehd1), and are mainly from a mega variety, Taichung 65. However, the parental lines of this variety were sensitive to photoperiod, thus, how Taichung 65 loss its sensitivity is a mystery. In this study, we used accession-specific single nucleotide polymorphism analysis to reveal the gene flow that occurred between different rice accessions decades ago and demonstrate that two landraces introgressed during the breeding process, which led to the loss of photoperiod sensitivity. Both Hd1 and Ehd1 may be important during artificial selection for flowering time, especially in a subtropical region such as Taiwan. This is a good example of introgression playing important roles during rice domestication.
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan; Department of Agronomy, National Taiwan University, Taipei 106, Taiwan. Electronic address: masker@gate.sinica.edu.tw.
authors.forename: Fu-Jin
authors.initials: FJ
authors.lastname: Wei
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan. Electronic address: botsai@gate.sinica.edu.tw.
authors.forename: Yuan-Ching
authors.initials: YC
authors.lastname: Tsai
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan. Electronic address: hpwu@gate.sinica.edu.tw.
authors.forename: Hshin-Ping
authors.initials: HP
authors.lastname: Wu
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan. Electronic address: melissa@gate.sinica.edu.tw.
authors.forename: Lin-Tzu
authors.initials: LT
authors.lastname: Huang
authors.affiliation: Taiwan International Cooperation and Development Fund, Taipei 111, Taiwan. Electronic address: yc.chen@icdf.org.tw.
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Soil and Water Conservation Bureau, Council of Agriculture, Nantou 540, Taiwan. Electronic address: r94621121@ntu.edu.tw.
authors.forename: Yi-Fang
authors.initials: YF
authors.lastname: Chen
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan; Institute of Botany, National Taiwan University, Taipei 106, Taiwan. Electronic address: ccwu1212@gate.sinica.edu.tw.
authors.forename: Cheng-Chieh
authors.initials: CC
authors.lastname: Wu
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan; Institute of Botany, National Taiwan University, Taipei 106, Taiwan. Electronic address: jillts@gate.sinica.edu.tw.
authors.forename: Yi-Tzu
authors.initials: YT
authors.lastname: Tseng
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan. Electronic address: bohsing@gate.sinica.edu.tw.
authors.forename: Yue-Ie C
authors.initials: YC
authors.lastname: Hsing
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics; D035264:Flowers / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D051456:Gene Flow; D018745:Genome, Plant / Q000235:genetics; D005838:Genotype; D054643:INDEL Mutation; D012275:Oryza / Q000145:classification / Q000235:genetics*; D017440:Photoperiod; D010802:Phylogeny; D000069600:Plant Breeding / Q000379:methods; D010940:Plant Proteins / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D013045:Species Specificity; D013997:Time Factors
chemical_list: D010940:Plant Proteins
keywords: Domestication; Heading date; Introgression; Next-generation sequencing; Rice