scholarly journals Morphological characterization of sympatric and allopatric populations of Petunia axillaris and P. exserta (Solanaceae)

2020 ◽  
Vol 192 (3) ◽  
pp. 550-567 ◽  
Author(s):  
Marcelo Costa Teixeira ◽  
Caroline Turchetto ◽  
Renan Maestri ◽  
Loreta B Freitas
Keyword(s):  
Morphological Characterization ◽  
Floral Display ◽  
Pollinator Attraction ◽  
Contact Zones ◽  
Low Genetic Diversity ◽  
Floral Diversity ◽  
Corolla Colour ◽  
Morphometric Analyses ◽  
Hybrid Classes ◽  
Petunia Axillaris

Abstract Floral morphological traits are frequently used to identify species, including those that are closely related and show low genetic diversity, and floral shape and colour are known to play an important role in diversification and species isolation. Floral morphology in Petunia (Solanaceae) is considered a driver of diversification because of its association with pollinators. Here, flower morphology was characterized through morphometric analyses and floral pigments. Our main aim was to determine corolla shape in populations of Petunia axillaris and P. exserta and their natural hybrids and how floral display, size and colour are involved in pollinator attraction. In addition, we investigated floral pigments in P. exserta and different hybrid classes. The results from morphometric analyses revealed that each species has a specific floral shape, independent of the collection site. By contrast, in two contact zones, a mosaic of floral phenotypes was observed with some hybrid classes based on corolla colour being placed close to P. exserta. The results suggest that several generations of hybrids or backcrossing could have given rise to this floral diversity in contact zones.

scholarly journals Disentangling the path of pollinator attraction in temporarily colored flowers

2020 ◽  
Author(s):  
Samuel Boff ◽  
Jessica Amaral Henrique ◽  
Anna Friedel ◽  
Josué Raizer
Keyword(s):  
Short Distance ◽  
Structural Equation ◽  
Predictor Variable ◽  
Floral Display ◽  
Long Distance ◽  
Pollinator Attraction ◽  
Generalist Species ◽  
Visitation Rate ◽  
Flower Visitors ◽  
Flower Visitation

Abstract Plants may use different strategies to attract pollinators in long distance (e.g. floral display) and in short distance (e.g. ratio between differentially colored flowers) scales. The Verbenaceae Lantana canescens Kunth is a wide spread species in open sites of the Brazilian Pantanal wetland. Individuals of this generalist species can produce a variable number of open inflorescences with yellow and white flowers that are organized in whorls. In this study we tested the hypothesis that increased floral display (long distance attraction) and the ratio between yellow and white flowers (short distance attraction) enhances the number of pollinator species and individuals. We observed flower visitors and calculated floral parameters in 38 plots of 1 m2 each, that contained a varying number of flowering L. canescens individuals. Non-metric multidimensional scaling and Bray-Curtis distances were used to account for flower visitor composition and the relative visitation rate, respectively. We used a structural equation model to test the power of each predictor variable on the visitation rate and a covariance analysis to disentangle the effect of each independent variable on the frequency of plant-pollinator interactions. We found that the number of flower visitors and the visitation rate increased with increasing number of inflorescences. Disentangling long and short distance attraction indicated that the number of inflorescences (per plot) and the number of yellow flowers (yellowing effect) contributed most to flower visitation at long and short distance, respectively.

scholarly journals Selfing Maintains Flower Colour Polymorphism in L. arvensis Despite High Inbreeding Depression

2019 ◽  
Author(s):  
Francisco Javier Jiménez-López ◽  
Pedro Luis Ortiz ◽  
María Talavera ◽  
Montserrat Arista
Keyword(s):  
Genetic Diversity ◽  
Genetic Differentiation ◽  
Inbreeding Depression ◽  
Low Frequency ◽  
Flower Colour ◽  
Colour Polymorphism ◽  
Pollinator Attraction ◽  
Mediterranean Populations ◽  
Low Genetic Diversity ◽  
Flower Colour Polymorphism

AbstractFlower colour polymorphism (FCP) is frequently associated with differences in pollinator attraction. FCP maintenance is intriguing, as positive directional selection by pollinators should result in the loss of polymorphism. Autonomous selfing could confer reproductive assurance when pollen is limited, and could be a mechanism for maintaining polymorphism unless inbreeding depression is high. We study the role of selfing in maintaining FCP in Lysimachia arvensis, a species with blue and red morphs co-occurring in Mediterranean populations, where pollinators negatively select for the red morph. We experimentally assessed inbreeding depression in both morphs in two Mediterranean populations and genetic diversity was studied via AFLP and SSR microsatellites in 20 populations. Between-morph genetic differentiation was high and the red morph had a lower genetic diversity, mainly in the Mediterranean. Results also show strong phenological differences between selfed and outcrossed progeny, and a high ID of the red morph. The low genetic diversity of the red morph is in concordance with a reproductive system based predominantly on selfing. However, ID suggests a limited capacity for red morph recruitment, according to its low frequency in polymorphic populations. Genetic differentiation between morphs indicates a low gene flow between them, opening the possibility of reproductive isolation and speciation in Lysimachia arvensis.

scholarly journals Flower morphological differentiation and plant-pollinator interactions among sympatric Aframomum species (Zingiberaceae) with floral trumpet type in the tropical African rainforest

2021 ◽  
Vol 154 (3) ◽  
pp. 447-457
Author(s):  
Elie Chrisnel Nzigou Doubindou ◽  
Alexandra C. Ley
Keyword(s):  
Competitive Exclusion ◽  
Morphological Differentiation ◽  
Species Boundaries ◽  
Morphological Parameters ◽  
Geographic Isolation ◽  
Pollinator Attraction ◽  
Nectar Volume ◽  
The Past ◽  
Floral Diversity ◽  
Plant Pollinator

Background and aims – Diversification in plant-pollinator interactions based on floral diversity is potentially a mechanism of coexistence in angiosperms. However, besides high floral diversity, some genera seemingly exhibit the same floral type in many of their species. This contradicts some expectations of competitive exclusion. We thus tested on a finer flower morphological scale whether five sympatric Aframomum species (61 spp., Zingiberaceae) in southeastern Gabon exhibiting the same general floral type (trumpet) were differentiated, and whether this resulted in different “pollinator niches”.Material and methods – We carried out a detailed survey measuring 18 flower morphological parameters as well as nectar volume (μl) and sugar concentration (% Brix) on five flowers per species and locality. Furthermore, we observed inflorescence phenology and pollinator activity from 8 am to 4 pm for 12 to 50 hours per species and conducted pollinator exclusion experiments.Key results – This study proves fine-scale flower morphological and resource differentiation within the trumpet floral type. Pollination-relevant parts of the flowers, however, remain constant across species. Our pollinator observations reveal the same broad bee pollinator spectrum for all observed simultaneously flowering sympatric species.Conclusion – As we could not detect a pollinator-based differentiation in the studied sympatric Aframomum species we assume that species boundaries developed randomly by genetic drift during geographic isolation in the past. The trumpet floral type and its pollinator guild, however, were maintained due to similar selection pressures in comparable habitats during isolation and are potentially an advantage for increased pollinator attraction through co-flowering.

scholarly journals Genetic basis and dual adaptive role of floral pigmentation in sunflowers

eLife ◽  
2022 ◽  
Vol 11 ◽  
Author(s):  
Marco Todesco ◽  
Natalia Bercovich ◽  
Amy Kim ◽  
Ivana Imerovski ◽  
Gregory L Owens ◽  
...  
Keyword(s):  
Genetic Basis ◽  
Myb Transcription Factor ◽  
Strongly Correlated ◽  
Pollinator Attraction ◽  
Floral Diversity ◽  
Complex Adaptive ◽  
Genetic And Environmental Factors ◽  
Floral Displays ◽  
Adaptive Role

Variation in floral displays, both between and within species, has been long known to be shaped by the mutualistic interactions that plants establish with their pollinators. However, increasing evidence suggests that abiotic selection pressures influence floral diversity as well. Here, we analyse the genetic and environmental factors that underlie patterns of floral pigmentation in wild sunflowers. While sunflower inflorescences appear invariably yellow to the human eye, they display extreme diversity for patterns of ultraviolet pigmentation, which are visible to most pollinators. We show that this diversity is largely controlled by cis-regulatory variation affecting a single MYB transcription factor, HaMYB111, through accumulation of ultraviolet (UV)-absorbing flavonol glycosides in ligules (the ‘petals’ of sunflower inflorescences). Different patterns of ultraviolet pigments in flowers are strongly correlated with pollinator preferences. Furthermore, variation for floral ultraviolet patterns is associated with environmental variables, especially relative humidity, across populations of wild sunflowers. Ligules with larger ultraviolet patterns, which are found in drier environments, show increased resistance to desiccation, suggesting a role in reducing water loss. The dual role of floral UV patterns in pollinator attraction and abiotic response reveals the complex adaptive balance underlying the evolution of floral traits.

Morphological Characterization of Mycobacteriophage R1

1974 ◽  
Vol 32 ◽  
pp. 254-255
Author(s):  
B. L. Soloff ◽  
T. A. Rado
Keyword(s):  
Carbon Source ◽  
Stationary Phase ◽  
Growth Phase ◽  
Minimal Medium ◽  
Morphological Characterization ◽  
Logarithmic Growth Phase ◽  
Complete Lysis ◽  
Lysogenic Culture ◽  
Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

A morphological and energy-dispersive x-ray spectroscopy (EDS) investigation of separator-grade cellophane

1994 ◽  
Vol 52 ◽  
pp. 430-431
Author(s):  
Michael E. Rock ◽  
Vern Kennedy ◽  
Bhaskar Deodhar ◽  
Thomas G. Stoebe
Keyword(s):  
Extrusion Process ◽  
Morphological Characterization ◽  
Energy Dispersive ◽  
Regenerated Cellulose ◽  
Battery System ◽  
X Ray ◽  
Functional Differences ◽  
Transmission Electron ◽  
Separator Material ◽  
Underwater Target

Cellophane is a composite polymer material, made up of regenerated cellulose (usually derived from wood pulp) which has been chemically transformed into "viscose", then formed into a (1 mil thickness) transparent sheet through an extrusion process. Although primarily produced for the food industry, cellophane's use as a separator material in the silver-zinc secondary battery system has proved to be another important market. We examined 14 samples from five producers of cellophane, which are being evaluated as the separator material for a silver/zinc alkaline battery system in an autonomous underwater target vehicle. Our intent was to identify structural and/or chemical differences between samples which could be related to the functional differences seen in the lifetimes of these various battery separators. The unused cellophane samples were examined by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). Cellophane samples were cross sectioned (125-150 nm) using a diamond knife on a RMC MT-6000 ultramicrotome. Sections were examined in a Philips 430-T TEM at 200 kV. Analysis included morphological characterization, and EDS (for chemical composition). EDS was performed using an EDAX windowless detector.

Morphological Characterization of Rhinacanthus Species of Sri Lanka

Planta Medica ◽  
2010 ◽  
Vol 76 (05) ◽  
Author(s):  
APPR Amarasinghe ◽  
RP Karunagoda ◽  
DSA Wijesundara
Keyword(s):  
Sri Lanka ◽  
Morphological Characterization
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