Progress on the mechanism of hormones regulating plant flower formation.

Flowering is the adaptability of plants in response to the environment, which is regulated by the complex flowering control network formed by a variety of exogenous and endogenous signals. Plant hormones, the most important endogenous signal participants, play important roles in the process of plant flowering. Recent reports reveal the pivotal roles of hormones in the epigenetic regulation and flowering promotion pathway. In addition, synergistic or antagonistic interaction has been observed among many hormones. Numerous hormones have been found to be involved in the regulation of the multiple flowering development regulation and signaling pathways mediated by DELLA protein in the gibberellin (GA) pathway. In this review, we summarize the recent advances ofthe flowering mechanisms related to GA pathway and discuss the effects of abscisic acid (ABA), auxin (IAA), cytokinin (CTK), salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) on flowering, including their cross-regulation with DELLA, miRNAs, and transcription factor (TFs). This review provides a reference for further comprehensive analysis of the hormone-regulated network of plant flower formation.