SLGT11 Controls Floral Organ Patterning and Floral Meristem Termination in Tomato

Abstract Background: Flower development affects fruit production directly in tomato. Despite the framework mediated by ABC genes have been established in Arabidopsis, the spatiotemporal precision of floral development in tomato has not been well examined.Results: Here, we analyzed a novel tomato mutant in which the normal development of stamens and carpels failed, resulting in ectopic formation of floral and shoot apical meristem in the fourth whorl position, which later developed into stem- and leaf-like structures. Using bulked segregant analysis (BSA), we assigned the causal mutation to the gene SLGT11 that encodes a transcription factor belonging to Trihelix gene family. Further RNAi silencing of SLGT11 verified the defective phenotypes of slf mutant. The failed termination of floral meristem and the occurrence of floral reversion in slf mutant indicate that SLGT11 functions as a non-canonical C type gene. Furthermore, we found that the defects in slf were substantially enhanced at higher temperature, with petals transformed into sepals, all stamens disappeared, and increased frequency of ectopic floral meristem.Conclusions: Together with the spatiotemporal expression pattern, we suggest that SLGT11 functions in floral organ patterning and termination of floral meristem identity in tomato.