Unraveling the Complexities of Flowering in Ornamental Plants: The Interplay of Genetics, Hormonal Networks, and Microbiome

Abstract

In ornamental plants, one of the most complex life processes, i.e., flowering, is regulated by interaction between the microbiota, hormones, and genes. Flowering plays an integral role in overall development and is quintessential for reproduction. Considering its importance, this review explores the complex mechanisms that determine the induction of flowering, highlighting the relationship between hormonal and genetic networks as well as the growing significance of the microbiome. Important genes involved in genetic control include FT, SOC1, and LFY. These genes react to environmental stimuli like photoperiod and vernalization. Auxins, cytokinin, and gibberellins are only a few hormone pathways important for floral growth and timing. The importance of plant-microbe interactions has been emphasized by current research, which shows that the microbiome affects flowering through processes like hormone production and availability of food. A comprehensive understanding of flowering induction is possible by integrating results from microbiota, hormones, and genetics studies, which may improve the breeding and culture of ornamental plants. For researchers to understand the complexity of flowering in ornamental plants and develop unique breeding strategies and improved floral qualities, it is critical to use interdisciplinary approaches, as this comprehensive investigation demonstrates.

Keywords: FT; LFY genes; SOC1; flower induction; plant hormones; plant microbiome interaction.

Figure 1

Different roles and applications of ornamental plants.

Figure 2

Schematic diagram illustrates the role of the rhizospheric microbiome in promoting floral development. The microbiome converts tryptophan into IAA (indole-3-acetic acid) and enhances the nitrogen cycle, both of which regulate floral development. The figure is adapted from the study reported by [53].

Figure 3

A molecule hierarchy regulating flowering in response to photoperiod. Arrows represent promotive effects between genes, while perpendicular lines represent repressive effects.

Figure 4

Factors regulating the transition from vegetative to flowering stages in plants. Various environmental and developmental signals, including the rhizospheric microbiome, nitrogen cycle, auxin induction, vernalization, photoperiod, and plant age, converge to regulate flowering. Key pathways and genes involved include FLC (FLOWERING LOCUS C) and FT (FLOWERING LOCUS T) for vernalization, SPB (SUPPRESSOR OF PHYTOCHROME B) for photoperiod, and SPL (SQUAMOSA PROMOTER BINDING PROTEIN-LIKE) for plant age. These signals modulate the expression of central flowering regulators such as SOC1 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1), TSF (TWIN SISTER OF FT), LFY (LEAFY), FT, PIN (PIN-FORMED), and YUC (YUCCA). Hormones like gibberellic acid (GA), jasmonic acid (JA), auxin, and cytokinins further facilitate the transition from vegetative growth to flowering.