Co-expression clustering across flower development identifies modules for diverse floral forms in Achimenes (Gesneriaceae)

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

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.

Network biology to uncover functional and structural properties of the plant immune system

In the last two decades, advances in network science have facilitated the discovery of important systems' entities in diverse biological networks. This graph-based technique has revealed numerous emergent properties of a system that enable us to understand several complex biological processes including plant immune systems. With the accumulation of multiomics data sets, the comprehensive understanding of plant-pathogen interactions can be achieved through the analyses and efficacious integration of multidimensional qualitative and quantitative relationships among the components of hosts and their microbes. This review highlights comparative network topology analyses in plant-pathogen co-expression networks and interactomes, outlines dynamic network modeling for cell-specific immune regulatory networks, and discusses the new frontiers of single-cell sequencing as well as multiomics data integration that are necessary for unraveling the intricacies of plant immune systems.

Chemical Basis of Floral Color Signals in Gesneriaceae: The Effect of Alternative Anthocyanin Pathways

Changes in floral pigmentation can have dramatic effects on angiosperm evolution by making flowers either attractive or inconspicuous to different pollinator groups. Flower color largely depends on the type and abundance of pigments produced in the petals, but it is still unclear whether similar color signals rely on same biosynthetic pathways and to which extent the activation of certain pathways influences the course of floral color evolution. To address these questions, we investigated the physical and chemical aspects of floral color in the Neotropical Gesnerioideae (ca. 1,200 spp.), in which two types of anthocyanins, hydroxyanthocyanins, and deoxyanthocyanins, have been recorded as floral pigments. Using spectrophotometry, we measured flower reflectance for over 150 species representing different clades and pollination syndromes. We analyzed these reflectance data to estimate how the Gesnerioideae flowers are perceived by bees and hummingbirds using the visual system models of these pollinators. Floral anthocyanins were further identified using high performance liquid chromatography coupled to mass spectrometry. We found that orange/red floral colors in Gesnerioideae are produced either by deoxyanthocyanins (e.g., apigenidin, luteolinidin) or hydroxyanthocyanins (e.g., pelargonidin). The presence of deoxyanthocyanins in several lineages suggests that the activation of the deoxyanthocyanin pathway has evolved multiple times in the Gesnerioideae. The hydroxyanthocyanin-producing flowers span a wide range of colors, which enables them to be discriminated by hummingbirds or bees. By contrast, color diversity among the deoxyanthocyanin-producing species is lower and mainly represented at longer wavelengths, which is in line with the hue discrimination optima for hummingbirds. These results indicate that Gesnerioideae have evolved two different biochemical mechanisms to generate orange/red flowers, which is associated with hummingbird pollination. Our findings also suggest that the activation of the deoxyanthocyanin pathway has restricted flower color diversification to orange/red hues, supporting the potential constraining role of this alternative biosynthetic pathway on the evolutionary outcome of phenotypical and ecological diversification.