Phenotypic expression of floral traits in hybrid zones provides insights into their genetic architecture

2020 ◽  
Vol 227 (3) ◽  
pp. 967-975
Author(s):  
Giovanni Scopece ◽  
Clarisse Palma‐Silva ◽  
Donata Cafasso ◽  
Christian Lexer ◽  
Salvatore Cozzolino
Keyword(s):  
Genetic Architecture ◽  
Phenotypic Expression ◽  
Floral Traits ◽  
Hybrid Zones

Hybrid Zones and the Genetic Architecture of a Barrier to Gene Flow Between Two Sunflower Species

Genetics ◽  
1999 ◽  
Vol 152 (2) ◽  
pp. 713-727 ◽  
Author(s):  
Loren H Rieseberg ◽  
Jeannette Whitton ◽  
Keith Gardner
Keyword(s):  
Genetic Study ◽  
Genetic Architecture ◽  
Chromosomal Rearrangements ◽  
Pollen Sterility ◽  
Model Organisms ◽  
Hybrid Zones ◽  
Reproductive Barriers ◽  
Natural Hybrid ◽  
Generation Times ◽  
Helianthus Petiolaris

Abstract Genetic analyses of reproductive barriers represent one of the few methods by which theories of speciation can be tested. However, genetic study is often restricted to model organisms that have short generation times and are easily propagated in the laboratory. Replicate hybrid zones with a diversity of recombinant genotypes of varying age offer increased resolution for genetic mapping experiments and expand the pool of organisms amenable to genetic study. Using 88 markers distributed across 17 chromosomes, we analyze the introgression of chromosomal segments of Helianthus petiolaris into H. annuus in three natural hybrid zones. Introgression was significantly reduced relative to neutral expectations for 26 chromosomal segments, suggesting that each segment contains one or more factors that contribute to isolation. Pollen sterility is significantly associated with 16 of these 26 segments, providing a straightforward explanation of why this subset of blocks is disadvantageous in hybrids. In addition, comparison of rates of introgression across colinear vs. rearranged chromosomes indicates that close to 50% of the barrier to introgression is due to chromosomal rearrangements. These results demonstrate the utility of hybrid zones for identifying factors contributing to isolation and verify the prediction of increased resolution relative to controlled crosses.

scholarly journals Genomics of isolation in hybrids

2012 ◽  
Vol 367 (1587) ◽  
pp. 439-450 ◽  
Author(s):  
Zachariah Gompert ◽  
Thomas L. Parchman ◽  
C. Alex Buerkle
Keyword(s):  
Reproductive Isolation ◽  
Genetic Architecture ◽  
Large Scale ◽  
Empirical Studies ◽  
Hybrid Zones ◽  
Direct Measure ◽  
Fitness Effects ◽  
Outlier Loci ◽  
Admixed Population ◽  
Genome Level

Hybrid zones are common in nature and can offer critical insights into the dynamics and components of reproductive isolation. Hybrids between diverged lineages are particularly informative about the genetic architecture of reproductive isolation, because introgression in an admixed population is a direct measure of isolation. In this paper, we combine simulations and a new statistical model to determine the extent to which different genetic architectures of isolation leave different signatures on genome-level patterns of introgression. We found that reproductive isolation caused by one or several loci of large effect caused greater heterogeneity in patterns of introgression than architectures involving many loci with small fitness effects, particularly when isolating factors were closely linked. The same conditions that led to heterogeneous introgression often resulted in a reasonable correspondence between outlier loci and the genetic loci that contributed to isolation. However, demographic conditions affected both of these results, highlighting potential limitations to the study of the speciation genomics. Further progress in understanding the genomics of speciation will require large-scale empirical studies of introgression in hybrid zones and model-based analyses, as well as more comprehensive modelling of the expected levels of isolation with different demographies and genetic architectures of isolation.

Abnormal and Unusual Inflorescences of Taro, Colocasia esculenta (Araceae)

1995 ◽  
Vol 43 (5) ◽  
pp. 475 ◽  
Author(s):  
A Ivancic
Keyword(s):  
Genetic Variation ◽  
Papua New Guinea ◽  
Solomon Islands ◽  
Phenotypic Expression ◽  
Colocasia Esculenta ◽  
Floral Traits ◽  
Breeding Programs ◽  
Future Improvement ◽  
Genetic Source ◽  
Flowering Ability

Taro (Colocasia esculenta (L.) Schott) breeding success depends strongly on hybridisation. The main problem in artificial hybridisation of taro is the irregularity of flowering and the occurrence of abnormal floral structures. Abnormal inflorescences appear continually in cultivated and wild taro populations in Papua New Guinea and the Solomon Islands. Their frequency and phenotypic expression are strongly influenced by the environment and cannot always be distinguished from unusual types which are influenced less or not at all by the environment. The frequency of abnormal inflorescences increases with the application of flower-inducing hormones which are frequently used in breeding programs. Abnormal and unusual inflorescences are classified into 16 groups. Several types can be efficiently used in hybridisation. Some of the genotypes characterised by unusual or abnormal floral traits represent a potential genetic source for future improvement of taro. They may be used as genetic markers, as the source of the genetic variation for ornamental characteristics or for the improvement of flowering ability.

scholarly journals Genetic Architecture of Floral Traits in Iris hexagona and Iris fulva

2013 ◽  
Vol 104 (6) ◽  
pp. 853-861 ◽  
Author(s):  
Amanda N. Brothers ◽  
Jessica G. Barb ◽  
Evangeline S. Ballerini ◽  
Douglas W. Drury ◽  
Steven J. Knapp ◽  
...  
Keyword(s):  
Genetic Architecture ◽  
Floral Traits ◽  
Iris Hexagona

Genetic architecture of male floral traits required for hybrid wheat breeding

2016 ◽  
Vol 129 (12) ◽  
pp. 2343-2357 ◽  
Author(s):  
Philipp H. G. Boeven ◽  
C. Friedrich H. Longin ◽  
Willmar L. Leiser ◽  
Sonja Kollers ◽  
Erhard Ebmeyer ◽  
...  
Keyword(s):  
Genetic Architecture ◽  
Wheat Breeding ◽  
Floral Traits ◽  
Hybrid Wheat

scholarly journals Investigating the genetic architecture of conditional strategies using the environmental threshold model

2015 ◽  
Vol 282 (1821) ◽  
pp. 20152075 ◽  
Author(s):  
Bruno A. Buzatto ◽  
Mathieu Buoro ◽  
Wade N. Hazel ◽  
Joseph L. Tomkins
Keyword(s):  
Genetic Variation ◽  
Genetic Architecture ◽  
Threshold Model ◽  
Evolutionary Game ◽  
Phenotypic Expression ◽  
Pedigree Information ◽  
Forficula Auricularia ◽  
Cryptic Variation ◽  
Proximate Cues ◽  
Environmental Threshold

The threshold expression of dichotomous phenotypes that are environmentally cued or induced comprise the vast majority of phenotypic dimorphisms in colour, morphology, behaviour and life history. Modelled as conditional strategies under the framework of evolutionary game theory, the quantitative genetic basis of these traits is a challenge to estimate. The challenge exists firstly because the phenotypic expression of the trait is dichotomous and secondly because the apparent environmental cue is separate from the biological signal pathway that induces the switch between phenotypes. It is the cryptic variation underlying the translation of cue to phenotype that we address here. With a ‘half-sib common environment’ and a ‘family-level split environment’ experiment, we examine the environmental and genetic influences that underlie male dimorphism in the earwig Forficula auricularia . From the conceptual framework of the latent environmental threshold (LET) model, we use pedigree information to dissect the genetic architecture of the threshold expression of forceps length. We investigate for the first time the strength of the correlation between observable and cryptic ‘proximate’ cues. Furthermore, in support of the environmental threshold model, we found no evidence for a genetic correlation between cue and the threshold between phenotypes. Our results show strong correlations between observable and proximate cues and less genetic variation for thresholds than previous studies have suggested. We discuss the importance of generating better estimates of the genetic variation for thresholds when investigating the genetic architecture and heritability of threshold traits. By investigating genetic architecture by means of the LET model, our study supports several key evolutionary ideas related to conditional strategies and improves our understanding of environmentally cued decisions.

scholarly journals Genetic architecture of floral traits in bee- and hummingbird-pollinated sister species of Aquilegia (columbine)

2021 ◽  
Author(s):  
Molly B. Edwards ◽  
Gary P. T. Choi ◽  
Nathan J. Derieg ◽  
Ya Min ◽  
Angie C. Diana ◽  
...  
Keyword(s):  
Qtl Mapping ◽  
Candidate Genes ◽  
Genetic Architecture ◽  
Genetic Basis ◽  
Single Locus ◽  
Floral Traits ◽  
Pollination Syndromes ◽  
Evolutionary Consequence ◽  
Floral Color ◽  
Hummingbird Pollination

Interactions with animal pollinators have helped shape the stunning diversity of flower morphologies across the angiosperms. A common evolutionary consequence of these interactions is that some flowers have converged on suites of traits, or pollination syndromes, that attract and reward specific pollinator groups. Determining the genetic basis of these floral pollination syndromes can help us understand the processes that contributed to the diversification of the angiosperms. Here, we characterize the genetic architecture of a bee-to-hummingbird pollination shift in Aquilegia (columbine) using QTL mapping of 17 floral traits encompassing color, nectar composition, and organ morphology. In this system, we find that the genetic architectures underlying differences in floral color are quite complex, and we identify several likely candidate genes involved in anthocyanin and carotenoid floral pigmentation. Most morphological and nectar traits also have complex genetic underpinnings; however, one of the key floral morphological phenotypes, nectar spur curvature, is shaped by a single locus of large effect.

scholarly journals Development of EST-SSR markers and association mapping with floral traits in Syringa oblata

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Yunyao Yang ◽  
Ruiqing He ◽  
Jian Zheng ◽  
Zenghui Hu ◽  
Jing Wu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Ssr Markers ◽  
Genetic Architecture ◽  
Genetic Research ◽  
Mixed Linear Model ◽  
Floral Traits ◽  
Dominant Type ◽  
High Level ◽  
Nucleotide Repeats

Abstract Background Lilac (Syringa oblata) is an important woody plant with high ornamental value. However, very limited genetic marker resources are currently available, and little is known about the genetic architecture of important ornamental traits for S. oblata, which is hindering its genetic studies. Therefore, it is of great significance to develop effective molecular markers and understand the genetic architecture of complex floral traits for the genetic research of S. oblata. Results In this study, a total of 10,988 SSRs were obtained from 9864 unigene sequences with an average of one SSR per 8.13 kb, of which di-nucleotide repeats were the dominant type (32.86%, 3611). A set of 2042 primer pairs were validated, out of which 932 (45.7%) exhibited successful amplifications, and 248 (12.1%) were polymorphic in eight S. oblata individuals. In addition, 30 polymorphic EST-SSR markers were further used to assess the genetic diversity and the population structure of 192 cultivated S. oblata individuals. Two hundred thirty-four alleles were detected, and the PIC values ranged from 0.23 to 0.88 with an average of 0.51, indicating a high level of genetic diversity within this cultivated population. The analysis of population structure showed two major subgroups in the association population. Finally, 20 significant associations were identified involving 17 markers with nine floral traits using the mixed linear model. Moreover, marker SO104, SO695 and SO790 had significant relationship with more than one trait. Conclusion The results showed newly developed markers were valuable resource and provided powerful tools for genetic breeding of lilac. Beyond that, our study could serve an efficient foundation for further facilitate genetic improvement of floral traits for lilac.

scholarly journals Development of EST-SSR Markers and Association Mapping with Floral Traits in Syringa oblata

2020 ◽  
Author(s):  
Yunyao Yang ◽  
Ruiqing He ◽  
Jian Zheng ◽  
Zenghui Hu ◽  
Jing Wu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Ssr Markers ◽  
Genetic Architecture ◽  
Genetic Research ◽  
Mixed Linear Model ◽  
Floral Traits ◽  
Dominant Type ◽  
High Level ◽  
Nucleotide Repeats

Abstract Background: Lilac (Syringa oblata) is an important woody plant with high ornamental value. However, very limited genetic marker resources are currently available, and little is known about the genetic architecture of important ornamental traits for S. oblata, which is hindering its genetic studies. Therefore, it is of great significance to develop effective molecular markers and understand the genetic architecture of complex floral traits for the genetic research of S. oblata.Results: In this study, a total of 10,988 SSRs were obtained from 9,864 unigene sequences with an average of one SSR per 8.13 kb, of which di-nucleotide repeats were the dominant type (32.86%, 3,611). A set of 2,042 primer pairs were validated, out of which 932 (45.7%) exhibited successful amplifications, and 248 (12.1%) were polymorphic in eight S. oblata individuals. In addition, 30 polymorphic EST-SSR markers were further used to assess the genetic diversity and the population structure of 192 cultivated S. oblata individuals. 234 alleles were detected, and the PIC values ranged from 0.23 to 0.88 with an average of 0.51, indicating a high level of genetic diversity within this cultivated population. The analysis of population structure showed two major subgroups in the association population. Finally, 20 significant associations were identified involving 17 markers with nine floral traits using the mixed linear model. Moreover, marker SO104, SO695 and SO790 had significant relationship with more than one trait.Conclusion: The results showed newly developed markers were valuable resource and provided powerful tools for genetic breeding of lilac. Beyond that, our study could serve an efficient foundation for further facilitate genetic improvement of floral traits for lilac.

Sign in / Sign up

Export Citation Format

Share Document