Invariant petal number is a characteristic of most flowers and is generally robust to genetic and environmental variation. We took advantage of the natural variation found in Cardamine hirsuta petal number to investigate the genetic basis of this trait in a case where robustness was lost during evolution. We used quantitative trait locus (QTL) analysis to characterize the genetic architecture o...

The floral organ identity gene APETALA3 (AP3) is a MADS-box transcription factor involved in stamen and petal identity that belongs to the B-class of the ABC model of flower development. Thalictrum (Ranunculaceae), an emerging model in the non-core eudicots, has AP3 homologs derived from both ancient and recent gene duplications. Prior work has shown that petals have been lost repeatedly and in...

Maintaining quality and longevity of cut flowers is one of the critical issues in the floriculture industry, especially in cut flowers; and one of the most important problems in chrysanthemum, as one of the most popular cut flowers. Therefore, an experiment was conducted based on completely randomized design as pulse treatment with the three factors: tea extracts with 4 levels (5, 10, 20, and 4...

In both Antirrhinum (Antirrhinum majus) and Arabidopsis (Arabidopsis thaliana), the floral B-function, which specifies petal and stamen development, is embedded in a heterodimer consisting of one DEFICIENS (DEF)/APETALA3 (AP3)-like and one GLOBOSA (GLO)/PISTILLATA (PI)-like MADS box protein. Here, we demonstrate that gene duplications in both the DEF/AP3 and GLO/PI lineages in Petunia hybrida (...

Gerbera hybrida is a cut-flower crop of global importance, and an understanding of the mechanisms underlying petal development is vital for the continued commercial development of this plant species. Brassinosteroids (BRs), a class of phytohormones, are known to play a major role in cell expansion, but their effect on petal growth in G. hybrida is largely unexplored. In this study, we found tha...

Changes in the oxygen uptake of petal slices by the cytochrome and alternative respiratory pathways were monitored during petal development in the arctic herb Saxifraga cernua. As the petals developed, rates of total respiration increased to a maximum rate during petal unfolding (day 4.5), and thereafter declined. Respiration in petals of all ages was at least partially resistant to cyanide, in...

Plant organ growth requires the proper transition from cell proliferation to cell expansion and differentiation. The CIN-TCP transcription factor gene TCP4 and its post-transcriptional regulator microRNA319 play a pivotal role in this process. In this study, we identified a pathway in which the product of the C2H2 zinc finger gene RABBIT EARS (RBE) regulates the transcription of TCP4 during Ara...

Petal growth is central to floral morphogenesis, but the underlying genetic basis of petal growth regulation is yet to be elucidated. In this study, we found that the basal region of the ray floret petals of Gerbera hybrida was the most sensitive to treatment with the phytohormones gibberellin (GA) and abscisic acid (ABA), which regulate cell expansion during petal growth in an antagonistic man...

The representation of knots by petal diagrams (Adams et al. 2012) naturally defines a sequence of distributions on the set of knots. In this article we establish some basic properties of this randomized knot model. We prove that in the random n-petal model the probability of every specific knot decays to zero as n, the number of petals, grows. In addition we improve the bounds relating the cros...

As a genetically determined structure, flower is an attractive object for developmental studies in plants. Flower development provides a good system for understanding cell differentiation and genetic mechanisms needed for organogenesis. The current molecular view on flower development has been based on studies on relatively few model species, like Arabidopsis and Antirrhinum. Research in model ...