Submitted to: Tropical Plant Biology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/22/2013
Publication Date: 3/1/2014
Citation: Heller, W.P., Z. Ying, T.L. Davenport, L.M. Keith, T.K. Matsumoto. 2014. Identification of members of the Dimocarpus longan Flowering Locus T gene family with divergent functions in flowering. Tropical Plant Biology. 7(1):19-29. Interpretive Summary: Potassium chlorate has been used to produce off-season longan fruit; however it is unknown on how this occurs. Scientists have identified a gene called FLOWERING LOCUS T (FT) that is responsible for flowering in other plants, such as the model plant Arabidopsis. Using molecular techniques we identified related genes in longan and when expressed in Arabidopsis we found that two of these genes cause flowering while expression of another inhibits flowering. Further characterization of these genes should enable us to better understand flowering in longan and other sub-tropical fruit trees.
Technical Abstract: Dimocarpus longan is a subtropical fruit crop whose year-round production relies on the application of KClO3 to induce flowering; however, the mechanism by which this chemical causes flowering is yet unknown. To further characterize floral signaling in this species, we have isolated three longan FLOWERING LOCUS T (FT)-like genes and studied their activities by heterologous expression in Arabidopsis. Expression of two of these genes (DlFT2 and DlFT3) accelerates flowering, whereas expression of the third gene (DlFT1) causes delayed flowering and produced floral morphology defects. This anti-florigenic protein may be a member of a class of FT-like family involved in flowering time control in biennial and perennial species. Surprisingly, KClO3 treatment also suppressed the expression of both DlFT2 and DlFT3 in a field trial.