scholarly journals Floral scent and species divergence in a pair of sexually deceptive orchids

2017 ◽  
Vol 7 (15) ◽  
pp. 6023-6034 ◽  
Author(s):  
Daniel D. L. Gervasi ◽  
Marc-Andre Selosse ◽  
Mathieu Sauve ◽  
Wittko Francke ◽  
Nicolas J. Vereecken ◽  
...  
Keyword(s):  
Floral Scent ◽  
Species Divergence ◽  
Sexually Deceptive Orchids

scholarly journals Hybrid floral scent novelty drives pollinator shift in sexually deceptive orchids

2010 ◽  
Vol 10 (1) ◽  
pp. 103 ◽  
Author(s):  
Nicolas J Vereecken ◽  
Salvatore Cozzolino ◽  
Florian P Schiestl
Keyword(s):  
Floral Scent ◽  
Sexually Deceptive Orchids ◽  
Pollinator Shift

scholarly journals Pollinator-Driven Speciation in Sexually Deceptive Orchids

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Shuqing Xu ◽  
Philipp M. Schlüter ◽  
Florian P. Schiestl
Keyword(s):  
Species Diversity ◽  
Floral Scent ◽  
Meta Analysis ◽  
Species Differentiation ◽  
Closely Related Species ◽  
Plant Group ◽  
Floral Isolation ◽  
Sexual Mimicry ◽  
Sexually Deceptive Orchids ◽  
Pollinator Shift

Pollinator-mediated selection has been suggested to play a major role for the origin and maintenance of the species diversity in orchids. Sexually deceptive orchids are one of the prime examples for rapid, pollinator-mediated plant radiations, with many species showing little genetic differentiation, lack of postzygotic barriers, but strong prezygotic reproductive isolation. These orchids mimic mating signals of female insects and employ male insects as pollinators. This kind of sexual mimicry leads to highly specialised pollination and provides a good system for investigating the process of pollinator-driven speciation. Here, we summarise the knowledge of key processes of speciation in this group of orchids and conduct a meta-analysis on traits that contribute to species differentiation, and thus potentially to speciation. Our study suggests that pollinator shift through changes in floral scent is predominant among closely related species in sexually deceptive orchids. Such shifts can provide a mechanism for pollinator-driven speciation in plants, if the resulting floral isolation is strong. Furthermore, changes in floral scent in these orchids are likely controlled by few genes. Together these factors suggest speciation in sexually deceptive orchids may happen rapidly and even in sympatry, which may explain the remarkable species diversity observed in this plant group.

scholarly journals Bayes Estimation of Species Divergence Times and Ancestral Population Sizes Using DNA Sequences From Multiple Loci

Genetics ◽  
2003 ◽  
Vol 164 (4) ◽  
pp. 1645-1656 ◽  
Author(s):  
Bruce Rannala ◽  
Ziheng Yang
Keyword(s):  
Dna Sequences ◽  
Gene Tree ◽  
Species Tree ◽  
Bayes Estimation ◽  
Ancestral Population ◽  
Divergence Times ◽  
Gene Trees ◽  
Species Divergence ◽  
Multiple Loci ◽  
Population Sizes

Abstract The effective population sizes of ancestral as well as modern species are important parameters in models of population genetics and human evolution. The commonly used method for estimating ancestral population sizes, based on counting mismatches between the species tree and the inferred gene trees, is highly biased as it ignores uncertainties in gene tree reconstruction. In this article, we develop a Bayes method for simultaneous estimation of the species divergence times and current and ancestral population sizes. The method uses DNA sequence data from multiple loci and extracts information about conflicts among gene tree topologies and coalescent times to estimate ancestral population sizes. The topology of the species tree is assumed known. A Markov chain Monte Carlo algorithm is implemented to integrate over uncertain gene trees and branch lengths (or coalescence times) at each locus as well as species divergence times. The method can handle any species tree and allows different numbers of sequences at different loci. We apply the method to published noncoding DNA sequences from the human and the great apes. There are strong correlations between posterior estimates of speciation times and ancestral population sizes. With the use of an informative prior for the human-chimpanzee divergence date, the population size of the common ancestor of the two species is estimated to be ∼20,000, with a 95% credibility interval (8000, 40,000). Our estimates, however, are affected by model assumptions as well as data quality. We suggest that reliable estimates have yet to await more data and more realistic models.

scholarly journals Floral Scent and Pollinators of Cypripedium calceolus L. at Different Latitudes

Diversity ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 5
Author(s):  
Herbert Braunschmid ◽  
Robin Guilhot ◽  
Stefan Dötterl
Keyword(s):  
Floral Scent ◽  
Latitudinal Gradients ◽  
Isolated Populations ◽  
Floral Scents ◽  
Selective Pressures ◽  
Octyl Acetate ◽  
Important Trait ◽  
Cypripedium Calceolus ◽  
Negative Frequency Dependent Selection ◽  
Plant Pollinator

Floral scent is an important trait in plant–pollinator interactions. It not only varies among plant species but also among populations within species. Such variability might be caused by various non–selective factors, or, as has been shown in some instances, might be the result of divergent selective pressures exerted by variable pollinator climates. Cypripedium calceolus is a Eurasian deceptive orchid pollinated mainly by bees, which spans wide altitudinal and latitudinal gradients in mainly quite isolated populations. In the present study, we investigated whether pollinators and floral scents vary among different latitudes. Floral scents of three C. calceolus populations in the Southern Alps were collected by dynamic headspace and analyzed by gas chromatography coupled to mass spectrometry (GC/MS). These data were completed by previously published scent data of the Northern Alps and Scandinavia. The scent characteristics were compared with information on pollinators recorded for present study or available in the literature. More than 80 scent compounds were overall recorded from plants of the three regions, mainly aliphatics, terpenoids, and aromatics. Seven compounds were found in all samples, and most samples were dominated by linalool and octyl acetate. Although scents differed among regions and populations, the main compounds were similar among regions. Andrena and Lasioglossum species were the main pollinators in all three regions, with Andrena being relatively more abundant than Lasioglossum in Scandinavia. We discuss natural selection mediated by pollinators and negative frequency–dependent selection as possible reasons for the identified variation of floral scent within and among populations and regions.

scholarly journals Genome-Wide Analysis and Characterization of the Aux/IAA Family Genes Related to Floral Scent Formation in Hedychium coronarium

2019 ◽  
Vol 20 (13) ◽  
pp. 3235 ◽  
Author(s):  
Yanguo Ke ◽  
Farhat Abbas ◽  
Yiwei Zhou ◽  
Rangcai Yu ◽  
Yuechong Yue ◽  
...  
Keyword(s):  
Gene Family ◽  
Developmental Stages ◽  
Floral Scent ◽  
Expression Profiles ◽  
Expression Patterns ◽  
Regulatory Elements ◽  
Virus Induced Gene Silencing ◽  
Cut Flowers ◽  
Flower Opening ◽  
Hedychium Coronarium

Auxin plays a key role in different plant growth and development processes, including flower opening and development. The perception and signaling of auxin depend on the cooperative action of various components, among which auxin/indole-3-acetic acid (Aux/IAA) proteins play an imperative role. In a recent study, the entire Aux/IAA gene family was identified and comprehensively analyzed in Hedychium coronarium, a scented species used as an ornamental plant for cut flowers. Phylogenetic analysis showed that the Aux/IAA gene family in H. coronarium is slightly contracted compared to Arabidopsis, with low levels of non-canonical proteins. Sequence analysis of promoters showed numerous cis-regulatory elements related to various phytohormones. HcIAA genes showed distinct expression patterns in different tissues and flower developmental stages, and some HcIAA genes showed significant responses to auxin and ethylene, indicating that Aux/IAAs may play an important role in linking hormone signaling pathways. Based on the expression profiles, HcIAA2, HcIAA4, HcIAA6 and HcIAA12, were selected as candidate genes and HcIAA2 and HcIAA4 were screened for further characterization. Downregulation of HcIAA2 and HcIAA4 by virus-induced gene silencing in H. coronarium flowers modified the total volatile compound content, suggesting that HcIAA2 and HcIAA4 play important roles in H. coronarium floral scent formation. The results presented here will provide insights into the putative roles of HcIAA genes and will assist the elucidation of their precise roles during floral scent formation.

Sign in / Sign up

Export Citation Format

Share Document