Tomato Delays Flowering Time by Regulating Different Genes Under Long-Day and Short-Day Conditions.

Photoperiod is a crucial inducer of plant flowering. Cycling DOF factors (CDFs) play pivotal roles in the flowering of long-day (LD) and short-day (SD) plants. However, the functions of in the photoperiod regulated flowering remain unclear in day-neutral plants. In the present study, tomato ( L. cv. "Ailsa Craig") seedlings of the wild-type and transgenic lines of overexpressing were treated with different photoperiods. The flowering time and the expression pattern of and other genes were investigated. The results showed that tomato , , , , and are homologs to (). expression levels were influenced by the developmental stage and the tissue location, and notably, the expression patterns throughout light environments showed two opposite trends. Among the overexpression transgenic lines, overexpressing delayed flowering time in both LD (16 h light/8 h dark) and SD (8 h light/16 h dark) conditions. Furthermore, led to an increase in the mRNA level of , a tomato gene, in LD conditions, while the transcription level of the other two genes, and , were up-regulated in SD conditions. Taken together, at the transcription level, our results demonstrated that played a significant role in controlling tomato flowering under LD and SD conditions, possibly through directly or indirectly regulating genes.