Identification of Sugar Beet Flowering Genes Based on Arabidopsis Homologous Genes

Transition from vegetative to reproductive growth is an important stage in plant’s life. Flowering pathways including photoperiod, vernalization, gibberellins, and autonomous pathway are regulated by different genes. Identification of flowering genes is essential for the development of bolting-resistant sugar beet cultivars. In this study, a set of 118 Arabidopsis thaliana genes involved in flowering time control were used as a reference to identify homologous counterparts in Expressed Sequence Tags (ESTs) and Transcriptome Shotgun Assembly (TSA) sequence of sugar beet. Based on obtained ESTs, primers were designed for Suppressor of Frigida 4 (SUF4), Curly Leaf (CLF), Constitutive Photomorphogenesis1 (COP1), and Cycling Dof Factor (CDF) genes. SUF4 and CLF are components of vernalization pathway and COP1 and CDF are in photoperiod pathway. The sequence regions of these genes were amplified using cDNA PCR technique, and compared with other identified sequences in Gene Bank. Four genes namely CLF, COP1, CDF and SUF4 were deposited in Gene Bank. Results showed that most of the flowering pathway genes in Arabidopsis are detectable in sugar beet which can be contributed to the understanding of the genetic control of bolting resistance.