Hybrid intermediacy between pollination syndromes in Penstemon, and the role of nectar in affecting hummingbird visitation

Botany ◽  
2009 ◽  
Vol 87 (3) ◽  
pp. 272-282 ◽  
Author(s):  
Paul Wilson ◽  
Elizabeth Anne Jordan
Keyword(s):  
Pollination Syndrome ◽  
Pollination Syndromes ◽  
Bee Pollination ◽  
Pollinator Attraction ◽  
Linear Effect ◽  
Linear Fashion ◽  
Additive Gene ◽  
Floral Characters ◽  
Additive Gene Expression

Flower size dimensions, colour, and nectar quantities potentially account for differences in pollinator species between Penstemon centranthifolius (Benth.) Benth. (tubular, red, nectar-rich, hummingbird pollinated) and Penstemon spectabilis Thurber (wide, purple, nectar-poor, hymenopteran pollinated). For this study, floral characters and pollinator attraction were measured for the two species, F1 hybrids, and backcrosses. Floral dimensions, nectar characters, and color spectra combined in the hybrids in a largely linear fashion, consistent with an interpretation of net additive gene expression. In other words, the changes from one pollination syndrome to another appeared to be quantitative. There were some deviations from linearity, but not so much as to obscure the linear effect. Generally, backcrosses were not more variable than F1 hybrids or pure parents. Hummingbirds preferred P. centranthifolius over P. spectabilis. The strength of this preference varied by year, and the birds did not respond to hybrids in a strictly linear fashion. When there was a preference, adding nectar hourly to under-visited plants quickly changed the foraging of hummingbirds. Bees in the genus Ceratina preferred the bee-pollination syndrome of P. spectabilis.

scholarly journals Evolution of pollination syndromes and corolla symmetry in Balsaminaceae reconstructed using phylogenetic comparative analyses

2020 ◽  
Author(s):  
Saroj Ruchisansakun ◽  
Arne Mertens ◽  
Steven B Janssens ◽  
Erik F Smets ◽  
Timotheüs van der Niet
Keyword(s):  
Phylogenetic Trees ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Plastid Dna ◽  
Pollination Syndrome ◽  
Pollination Syndromes ◽  
Bee Pollination ◽  
Floral Symmetry ◽  
Considerable Uncertainty ◽  
Pollination Systems

Abstract Background and Aims Floral diversity as a result of plant–pollinator interactions can evolve by two distinct processes: shifts between pollination systems or divergent use of the same pollinator. Although both are pollinator driven, the mode, relative importance and interdependence of these different processes are rarely studied simultaneously. Here we apply a phylogenetic approach using the Balsaminaceae (including the species-rich genus Impatiens) to simultaneously quantify shifts in pollination syndromes (as inferred from the shape and colour of the perianth), as well as divergent use of the same pollinator (inferred from corolla symmetry). Methods For 282 species we coded pollination syndromes based on associations between floral traits and known pollination systems, and assessed corolla symmetry. The evolution of these traits was reconstructed using parsimony- and model-based approaches, using phylogenetic trees derived from phylogenetic analyses of nuclear ribosomal and plastid DNA sequence data. Key Results A total of 71 % of studied species have a bee pollination syndrome, 22 % a bimodal syndrome (Lepidoptera and bees), 3 % a bird pollination syndrome and 5 % a syndrome of autogamy, while 19 % of species have an asymmetrical corolla. Although floral symmetry and pollination syndromes are both evolutionarily labile, the latter shifts more frequently. Shifts in floral symmetry occurred mainly in the direction towards asymmetry, but there was considerable uncertainty in the pattern of shift direction for pollination syndrome. Shifts towards asymmetrical flowers were associated with a bee pollination syndrome. Conclusion Floral evolution in Impatiens has occurred through both pollination syndrome shifts and divergent use of the same pollinator. Although the former appears more frequent, the latter is likely to be underestimated. Shifts in floral symmetry and pollination syndromes depend on each other but also partly on the region in which these shifts take place, suggesting that the occurrence of pollinator-driven evolution may be determined by the availability of pollinator species at large geographical scales.

scholarly journals Genetic architecture of pollination syndrome transition between hummingbird-specialist and generalist species in the genus Rhytidophyllum (Gesneriaceae)

2015 ◽  
Author(s):  
Hermine Alexandre ◽  
Justine Vrignaud ◽  
Brigitte Mangin ◽  
Simon Joly
Keyword(s):  
Genetic Architecture ◽  
Genetic Basis ◽  
Pollination Syndrome ◽  
Pollination Syndromes ◽  
Generalist Species ◽  
Nectar Volume ◽  
Key Factor ◽  
The Caribbean ◽  
Specialist Species ◽  
Floral Characters

Adaptation to pollinators is a key factor of diversification in angiosperms. The Caribbean sister genera Rhytidophyllum and Gesneria present an important diversification of floral characters. Most of their species can be divided in two major pollination syndromes. Large-open flowers with pale colours and great amount of nectar represent the generalist syndrome, while the hummingbird-specialist syndrome corresponds to red tubular flowers with a less important nectar volume. Repeated convergent evolution toward the generalist syndrome in this group suggests that such transitions rely on few genes of moderate to large effect. To test this hypothesis, we built a linkage map and performed a QTL detection for divergent pollination syndrome traits by crossing one specimen of the generalist species Rhytidophyllum auriculatum with one specimen of the hummingbird pollinated R. rupincola. Using geometric morphometrics and univariate traits measurements, we found that floral shape among the second-generation hybrids is correlated with morphological variation observed between generalist and hummingbird-specialist species at the genus level. The QTL analysis showed that colour and nectar volume variation between syndromes involve each one major QTL while floral shape has a more complex genetic basis and rely on few genes of moderate effect. Finally we did not detect any genetic linkage between the QTLs underlying those traits. This genetic independence of traits could have facilitated evolution toward optimal syndromes.

scholarly journals Genome-wide meta-analysis of maize heterosis reveals the potential role of additive gene expression at pericentromeric loci

2014 ◽  
Vol 14 (1) ◽  
pp. 88 ◽  
Author(s):  
Alexander Thiemann ◽  
Junjie Fu ◽  
Felix Seifert ◽  
Robert T Grant-Downton ◽  
Tobias A Schrag ◽  
...  
Keyword(s):  
Gene Expression ◽  
Potential Role ◽  
Meta Analysis ◽  
Genome Wide ◽  
Additive Gene ◽  
Additive Gene Expression

scholarly journals Modularity and evolution of flower shape: the role of efficiency, development, and spandrels in Erica

2019 ◽  
Author(s):  
Dieter Reich ◽  
Andreas Berger ◽  
Maria von Balthazar ◽  
Marion Chartier ◽  
Mahboubeh Sherafati ◽  
...  
Keyword(s):  
Recent Common Ancestor ◽  
Pollination Syndrome ◽  
Pollen Deposition ◽  
List Type ◽  
Pollination Syndromes ◽  
Flower Shape ◽  
Most Recent Common Ancestor ◽  
3D Data ◽  
First Time

SummaryThree hypotheses can explain floral modularity: the attraction-reproduction, the efficiency, and the developmental hypotheses.In order to test these hypotheses and understand if pollination specialisation and pollination syndrome influence floral modularity, we focussed on the genus Erica: we gathered 3D data from flowers of species with diverse pollination syndromes via Computed Tomography, and analysed their shape via geometric morphometrics. In order to provide an evolutionary framework for our results we tested the evolutionary mode of floral shape, size, and integration under pollination syndrome regimes, and - for the first time-reconstructed the high-dimensional floral shape of their most recent common ancestor.We demonstrate, for the first time, that the modularity of generalist flowers depends on development and that of specialists is linked to efficiency: in bird syndrome flower, efficiency modules were associated with pollen deposition and receipt, whereas in long-proboscid fly syndrome, they were associated with restricting the access to the floral reward. Only shape PC1 showed selection towards multiple optima, suggesting that PC1 was co-opted by evolution to adapt flowers to novel pollinators. Whole floral shape followed an OU model of evolution, and demonstrated relatively late differentiation.Flower shape modularity thus crucially depends on pollinator specialisation and class.

scholarly journals Genetic architecture of pollination syndrome transition between hummingbird-specialist and generalist species in the genus Rhytidophyllum (Gesneriaceae)

2015 ◽  
Author(s):  
Hermine Alexandre ◽  
Justine Vrignaud ◽  
Brigitte Mangin ◽  
Simon Joly
Keyword(s):  
Genetic Architecture ◽  
Genetic Basis ◽  
Pollination Syndrome ◽  
Pollination Syndromes ◽  
Generalist Species ◽  
Nectar Volume ◽  
Key Factor ◽  
The Caribbean ◽  
Specialist Species ◽  
Floral Characters

Adaptation to pollinators is a key factor of diversification in angiosperms. The Caribbean sister genera Rhytidophyllum and Gesneria present an important diversification of floral characters. Most of their species can be divided in two major pollination syndromes. Large-open flowers with pale colours and great amount of nectar represent the generalist syndrome, while the hummingbird-specialist syndrome corresponds to red tubular flowers with a less important nectar volume. Repeated convergent evolution toward the generalist syndrome in this group suggests that such transitions rely on few genes of moderate to large effect. To test this hypothesis, we built a linkage map and performed a QTL detection for divergent pollination syndrome traits by crossing one specimen of the generalist species Rhytidophyllum auriculatum with one specimen of the hummingbird pollinated R. rupincola. Using geometric morphometrics and univariate traits measurements, we found that floral shape among the second-generation hybrids is correlated with morphological variation observed between generalist and hummingbird-specialist species at the genus level. The QTL analysis showed that colour and nectar volume variation between syndromes involve each one major QTL while floral shape has a more complex genetic basis and rely on few genes of moderate effect. Finally we did not detect any genetic linkage between the QTLs underlying those traits. This genetic independence of traits could have facilitated evolution toward optimal syndromes.

scholarly journals Genetic architecture of pollination syndrome transition between hummingbird-specialist and generalist species in the genus Rhytidophyllum (Gesneriaceae)

2015 ◽  
Author(s):  
Hermine Alexandre ◽  
Justine Vrignaud ◽  
Brigitte Mangin ◽  
Simon Joly
Keyword(s):  
Genetic Architecture ◽  
Genetic Basis ◽  
Pollination Syndrome ◽  
Pollination Syndromes ◽  
Generalist Species ◽  
Nectar Volume ◽  
Key Factor ◽  
The Caribbean ◽  
Specialist Species ◽  
Floral Characters

Adaptation to pollinators is a key factor of diversification in angiosperms. The Caribbean sister genera Rhytidophyllum and Gesneria present an important diversification of floral characters. Most of their species can be divided in two major pollination syndromes. Large-open flowers with pale colours and great amount of nectar represent the generalist syndrome, while the hummingbird-specialist syndrome corresponds to red tubular flowers with a less important nectar volume. Repeated convergent evolution toward the generalist syndrome in this group suggests that such transitions rely on few genes of moderate to large effect. To test this hypothesis, we built a linkage map and performed a QTL detection for divergent pollination syndrome traits by crossing one specimen of the generalist species Rhytidophyllum auriculatum with one specimen of the hummingbird pollinated R. rupincola. Using geometric morphometrics and univariate traits measurements, we found that floral shape among the second-generation hybrids is correlated with morphological variation observed between generalist and hummingbird-specialist species at the genus level. The QTL analysis showed that colour and nectar volume variation between syndromes involve each one major QTL while floral shape has a more complex genetic basis and rely on few genes of moderate effect. Finally we did not detect any genetic linkage between the QTLs underlying those traits. This genetic independence of traits could have facilitated evolution toward optimal syndromes.

The Role of Addington V Texas on Involuntary Civil Commitment

1989 ◽  
Vol 65 (3_suppl2) ◽  
pp. 1211-1215 ◽  
Author(s):  
J. Ray Hays
Keyword(s):  
United States ◽  
No Reduction ◽  
Burden Of Proof ◽  
United States Supreme Court ◽  
The United States ◽  
Convincing Evidence ◽  
Involuntary Commitment ◽  
United States Supreme ◽  
Linear Fashion

The United States Supreme Court in 1979 set the standard for involuntary commitment. This decision, styled Addington v Texas, raised the burden of proof required to commit persons from the usual civil burden of proof of “preponderance of the evidence” to “clear and convincing” evidence. There was no reduction in the rates of commitment as a result of the decision. The proportion of patients committed in Texas grew in almost linear fashion during the years 1972–1986. Various economic, sociological, and treatment factors may have more influence on commitment of patients than does a court decision.

scholarly journals Assessment of genetic diversity and estimation of genetic parameters for remobilization related traits of wheat under drought conditions

Genetika ◽  
2016 ◽  
Vol 48 (1) ◽  
pp. 139-149
Author(s):  
Ezatollah Farshadfar ◽  
Reza Amiri
Keyword(s):  
Dry Matter ◽  
Genetic Parameters ◽  
Predominant Role ◽  
Genetic Potential ◽  
Cropping Season ◽  
Additive Gene ◽  
Genetic Techniques ◽  
Selection Of ◽  
Kernel Yield

In order to evaluate genetic variability and estimation of remobilization related traits in wheat using biometrical genetic techniques an experiment was conducted in a randomized complete blocks design with three replicates under post-anthesis drought stress conditions in the Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran during 2011-2012 cropping season. The results of analysis of variance showed significant differences between the genotypes for all studied traits except current photosynthesis (CP) and current photosynthesis share into kernel yield (CPSKY). High genetic gain and broad sense heritability estimates were observed for penultimate remobilization share into kernel yield (PenRSKY) and internodes remobilization share into kernel yield (IRSKY) indicating high genetic potential, low effect of environment and predominant role of additive gene effect on their expression. Spike dry matter remobilization (SDMR), spike dry matter remobilization efficiency (SDMRE) and spike remobilization share into kernel yield (SRSKY) exhibited the highest phenotypic and genetic positive correlation with kernel yield (KY). Moreover, the highest genotypic and phenotypic covariance was observed between kernel yield (KY) and SDMR, CP, SDMRE and SRSKY, respectively. The highest environmental covariance was identified between kernel yield (KY), peduncle dry matter remobilization (PedDMR) and penultimate dry matter remobilization (PenDMR), respectively. High co-heritability was detected between SDMRE and PedDMR, PedDMRE and PenDMR and between peduncle remobilization share into kernel yield (PedRSKY) and internodes dry matter remobilization efficiency (IDMRE), suggesting that selection of either of the traits would simultaneously affect the others, positively.

Cryptic dioecy in Actinidia polygama: a test of the pollinator attraction hypothesis

2004 ◽  
Vol 82 (2) ◽  
pp. 214-218 ◽  
Author(s):  
Tetsuhiro Kawagoe ◽  
Nobuhiko Suzuki
Keyword(s):  
Fruit Production ◽  
Sexual System ◽  
Dioecious Species ◽  
Pollinator Attraction ◽  
Cryptic Dioecy ◽  
Actinidia Polygama ◽  
Unisexual Flowers ◽  
Sterile Pollen ◽  
Female Flowers

Female flowers of some dioecious species are known to develop stamens with sterile pollen, a sexual system known as cryptic dioecy. A convincing hypothesis explaining this phenomenon is that stamens in female flowers attract pollinators and so ensure seed production. However, because this hypothesis has rarely been tested experimentally, we tested it in a cryptically dioecious species, Actinidia polygama (Sieb. et Zucc.) Planch. ex Maxim. Our findings show that pollinators do not show a consistent preference based on the sex of the flowers, and that the removal of stamens from female flowers results in a significant reduction in the frequency of insect visits and fruit production. These results strongly support the pollinator attraction hypothesis in A. polygama. Given the evident role of stamens in female flowers in A. polygama reproduction, we discuss why cryptic dioecy is a rare phenomenon.Key words: Actinidia polygama, cryptic dioecy, pseudopollen, pollinator attraction, unisexual flowers.

scholarly journals Relative Role of Flower Color and Scent on Pollinator Attraction: Experimental Tests using F1 and F2 Hybrids of Daylily and Nightlily

PLoS ONE ◽  
2012 ◽  
Vol 7 (6) ◽  
pp. e39010 ◽  
Author(s):  
Shun K. Hirota ◽  
Kozue Nitta ◽  
Yuni Kim ◽  
Aya Kato ◽  
Nobumitsu Kawakubo ◽  
...  
Keyword(s):  
Experimental Tests ◽  
Flower Color ◽  
Relative Role ◽  
Pollinator Attraction ◽  
F2 Hybrids
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