Table 2.

A simplified presentation of the crosstalk between different phytohormones and regulation of flowering time in response to photoperiod.

Interacting phytohormones	Organism	Type of interaction	Phytohormone regulation	Flowering phenotype	Photoperiod conditions	References
GA, ABA	Arabidopsis	Antagonistic	Low GA, Low ABA	Rescue of the late-flowering phenotype of ga-1 by aba2	LD and SD	Domagalska et al., 2010
GA, ABA	Arabidopsis	Antagonistic	Low GA, High ABA	Late flowering: Upregulation of GAox7 by NCED6	LD	Shu et al., 2016
GA, ABA	Arabidopsis	Antagonistic	High GA, Low ABA	Early flowering: Inhibition of ABI4 by GA hormones	LD	Shu et al., 2016
GA, ABA	Rice	Antagonistic	Low GA, High ABA	Late flowering: Upregulation of OsEUI by OsAP2	LD	Yaish et al., 2010
GA, ABA	Rice	Antagonistic	High GA, Low ABA	Early flowering: Inhibition of NCED1 by GA hormones	LD	Yaish et al., 2010
CK, GA	Arabidopsis	Synergistic	High CK, High GA	Late flowering: downregulation of SOC1	LD	Richter et al., 2010; Ranftl et al., 2016
GA, BR	Arabidopsis	Partially synergistic	High GA, Low BR	Activation of GA synthesis rescued the late-flowering phenotype of bri-1 mutants	LD	Domagalska et al., 2010; Unterholzner et al., 2015
BR, ABA	Arabidopsis	Antagonistic	High ABA, Low BR	Late flowering: ABA inhibits BR synthesis by inhibition of the PIF − BES1 complex	LD	Hayes et al., 2019