title: A transposon insertion in FLOWERING LOCUS T is associated with delayed flowering in Brassica rapa.
abstract: Long days and vernalization accelerate the transition from vegetative growth to reproductive growth in Brassica rapa. Bolting before plants reach the harvesting stage is a serious problem in B. rapa vegetable crop cultivation. The genetic dissection of flowering time is important for breeding of premature bolting-resistant B. rapa crops. Using a recombinant inbred line (RIL) population, we twice detected two major quantitative trait loci (QTLs) for flowering time in two different growing seasons that were located on chromosomes A02 and A07, respectively. We hypothesized that an orthologue of the Arabidopsis thaliana FLOWERING LOCUS T (FT) gene, named as BrFT2, was the candidate gene underlying the QTL localized to A07. A transposon insertion in the second intron of BrFT2 was detected in one of the parental lines, which was predicted to generate a loss-of-function allele. Transcription analysis revealed that the BrFT2 transcript was not present in the parental line that harbored the mutated allele. RILs carrying only the mutated BrFT2 allele showed delayed flowering regardless of growing seasons when compared to RILs carrying the wild-type BrFT2 allele. These data suggest that BrFT2 is involved in flowering time regulation in controlling flowering time in B. rapa.
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: yimingzhangbp@163.com.
authors.forename: Xueming
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: mlbio@126.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Meng
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: lb_bobo@aliyun.com.
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: huyunyanspring@126.com.
authors.forename: Yunyan
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: chengfeng@caas.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Cheng
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: liangjianli@caas.cn.
authors.forename: Jianli
authors.initials: J
authors.lastname: Liang
authors.affiliation: Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708PB Wageningen, the Netherlands. Electronic address: mark.aarts@wur.nl.
authors.forename: Mark G M
authors.initials: MG
authors.lastname: Aarts
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: wangxiaowu@caas.cn.
authors.forename: Xiaowu
authors.initials: X
authors.lastname: Wang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Zhongguancun Southern Street 12, 100081 Beijing, China. Electronic address: wujian@caas.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Wu
mesh_terms: D029741:Brassica rapa / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D002874:Chromosome Mapping; D035264:Flowers / Q000235:genetics* / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D040641:Quantitative Trait Loci
chemical_list: D010940:Plant Proteins
keywords: Brassica rapa; FLOWERING LOCUS T; Flowering time; Loss-of-function allele; Quantitative trait locus (QTL)