Identification and characterization of FT/TFL1 gene family in cucumber

In Arabidopsis, FLOWERING LOCUS T (FT) and TERMINAL FLOWER 1 (TFL1) are known to control growth habit of determinace or indeterminate type. In cucumber (Cucumis sativus L.), any FT or TFL1 homolog is expected to be the candidate for the gene controlling the growth habit. Most cucumber cultivars show indeterminate type of growth habits. For more effective breeding, it is necessary to develop determinate type cultivars. In this study, we isolated one FT and five TFL1 homologs in cucumber. On these homologs, the genomic organizations, phylogenetic relationships, expression patterns, and linkage to growth habit are elucidated herein. Through genetic analysis of F-2 individuals, two homologs did not co-segregate with the determinate-indeterminate phenotypes. On the other hand, different expression patterns of several homologs were detected between determinate and indeterminate cultivars.