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Shaw AJ, Duffy AM, Nieto-Lugilde M, Aguero B, Schuette S, Robinson S, Loveland J, Hicks KA, Weston D, Piatkowski B, Kolton M, Koska JE, Healey AL. Clonality, local population structure and gametophyte sex ratios in cryptic species of the Sphagnum magellanicum complex. ANNALS OF BOTANY 2023; 132:77-94. [PMID: 37417448 PMCID: PMC10550268 DOI: 10.1093/aob/mcad077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 07/06/2023] [Indexed: 07/08/2023]
Abstract
BACKGROUND AND AIMS Sphagnum (peatmoss) comprises a moss (Bryophyta) clade with ~300-500 species. The genus has unparalleled ecological importance because Sphagnum-dominated peatlands store almost a third of the terrestrial carbon pool and peatmosses engineer the formation and microtopography of peatlands. Genomic resources for Sphagnum are being actively expanded, but many aspects of their biology are still poorly known. Among these are the degree to which Sphagnum species reproduce asexually, and the relative frequencies of male and female gametophytes in these haploid-dominant plants. We assess clonality and gametophyte sex ratios and test hypotheses about the local-scale distribution of clones and sexes in four North American species of the S. magellanicum complex. These four species are difficult to distinguish morphologically and are very closely related. We also assess microbial communities associated with Sphagnum host plant clones and sexes at two sites. METHODS Four hundred and five samples of the four species, representing 57 populations, were subjected to restriction site-associated DNA sequencing (RADseq). Analyses of population structure and clonality based on the molecular data utilized both phylogenetic and phenetic approaches. Multi-locus genotypes (genets) were identified using the RADseq data. Sexes of sampled ramets were determined using a molecular approach that utilized coverage of loci on the sex chromosomes after the method was validated using a sample of plants that expressed sex phenotypically. Sex ratios were estimated for each species, and populations within species. Difference in fitness between genets was estimated as the numbers of ramets each genet comprised. Degrees of clonality [numbers of genets/numbers of ramets (samples)] within species, among sites, and between gametophyte sexes were estimated. Sex ratios were estimated for each species, and populations within species. Sphagnum-associated microbial communities were assessed at two sites in relation to Sphagnum clonality and sex. KEY RESULTS All four species appear to engage in a mixture of sexual and asexual (clonal) reproduction. A single ramet represents most genets but two to eight ramets were dsumbers ansd text etected for some genets. Only one genet is represented by ramets in multiple populations; all other genets are restricted to a single population. Within populations ramets of individual genets are spatially clustered, suggesting limited dispersal even within peatlands. Sex ratios are male-biased in S. diabolicum but female-biased in the other three species, although significantly so only in S. divinum. Neither species nor males/females differ in levels of clonal propagation. At St Regis Lake (NY) and Franklin Bog (VT), microbial community composition is strongly differentiated between the sites, but differences between species, genets and sexes were not detected. Within S. divinum, however, female gametophytes harboured two to three times the number of microbial taxa as males. CONCLUSIONS These four Sphagnum species all exhibit similar reproductive patterns that result from a mixture of sexual and asexual reproduction. The spatial patterns of clonally replicated ramets of genets suggest that these species fall between the so-called phalanx patterns, where genets abut one another but do not extensively mix because of limited ramet fragmentation, and the guerrilla patterns, where extensive genet fragmentation and dispersal result in greater mixing of different genets. Although sex ratios in bryophytes are most often female-biased, both male and female biases occur in this complex of closely related species. The association of far greater microbial diversity for female gametophytes in S. divinum, which has a female-biased sex ratio, suggests additional research to determine if levels of microbial diversity are consistently correlated with differing patterns of sex ratio biases.
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Affiliation(s)
- A Jonathan Shaw
- Department of Biology & L. E. Anderson Bryophyte Herbarium, Duke University, Durham, NC, 27708, USA
| | - Aaron M Duffy
- Department of Biology & L. E. Anderson Bryophyte Herbarium, Duke University, Durham, NC, 27708, USA
| | - Marta Nieto-Lugilde
- Department of Biology & L. E. Anderson Bryophyte Herbarium, Duke University, Durham, NC, 27708, USA
| | - Blanka Aguero
- Department of Biology & L. E. Anderson Bryophyte Herbarium, Duke University, Durham, NC, 27708, USA
| | - Scott Schuette
- Pennsylvania Natural Heritage Program, Western Pennsylvania Conservancy, Pittsburgh, PA, 15222, USA
| | - Sean Robinson
- Department of Biology, SUNY Oneonta, Oneonta, NY, 13820, USA
| | - James Loveland
- Department of Biology, Kenyon College, Gambier, OH 43022, USA
| | - Karen A Hicks
- Department of Biology, Kenyon College, Gambier, OH 43022, USA
| | - David Weston
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Bryan Piatkowski
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Max Kolton
- The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, 8499000, Israel
| | - Joel E Koska
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Adam L Healey
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
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2
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Lavaut E, Valero M, Mauger S, Guillemin ML, Destombe C, Dufay M. Sexual selection in seaweed? Testing Bateman's principles in the red alga Gracilaria gracilis. Proc Biol Sci 2023; 290:20231668. [PMID: 37700657 PMCID: PMC10498045 DOI: 10.1098/rspb.2023.1668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 08/21/2023] [Indexed: 09/14/2023] Open
Abstract
In anisogamous species, sexual selection is expected to be stronger in males. Bateman's principles state that the variance in (i) reproductive and (ii) mating success is greater for males, and (iii) the relationship between reproductive success and mating success (the Bateman gradient) is also stronger for males than for females. Sexual selection, based on Bateman's principles, has been demonstrated in animals and some angiosperms, but never in a seaweed. Here we focus on the oogamous haploid-diploid rhodophyte Gracilaria gracilis in which previous studies have shown evidence for non-random mating, suggesting the existence of male-male competition and female choice. We estimated mating and reproductive success using paternity analyses in a natural population where up to 92% of fertilizations occurred between partners of that population. The results show that the variance in mating success is significantly greater in males than in females and that the Bateman gradient is positive only in males. Distance to female partners also explains a minor part of the variance in male mating success. Although there is no evidence for sexual dimorphism, our study supports the hypothesis that sexual selection occurs in G. gracilis, probably on male traits, even if we cannot observe, characterize or quantify them yet.
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Affiliation(s)
- E. Lavaut
- IRL EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688 Roscoff cedex, France
| | - M. Valero
- IRL EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688 Roscoff cedex, France
| | - S. Mauger
- IRL EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688 Roscoff cedex, France
| | - M. L. Guillemin
- IRL EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688 Roscoff cedex, France
- Núcleo Milenio MASH, Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - C. Destombe
- IRL EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688 Roscoff cedex, France
| | - M. Dufay
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
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3
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Healey AL, Piatkowski B, Lovell JT, Sreedasyam A, Carey SB, Mamidi S, Shu S, Plott C, Jenkins J, Lawrence T, Aguero B, Carrell AA, Nieto-Lugilde M, Talag J, Duffy A, Jawdy S, Carter KR, Boston LB, Jones T, Jaramillo-Chico J, Harkess A, Barry K, Keymanesh K, Bauer D, Grimwood J, Gunter L, Schmutz J, Weston DJ, Shaw AJ. Newly identified sex chromosomes in the Sphagnum (peat moss) genome alter carbon sequestration and ecosystem dynamics. NATURE PLANTS 2023; 9:238-254. [PMID: 36747050 PMCID: PMC9946827 DOI: 10.1038/s41477-022-01333-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 12/13/2022] [Indexed: 06/18/2023]
Abstract
Peatlands are crucial sinks for atmospheric carbon but are critically threatened due to warming climates. Sphagnum (peat moss) species are keystone members of peatland communities where they actively engineer hyperacidic conditions, which improves their competitive advantage and accelerates ecosystem-level carbon sequestration. To dissect the molecular and physiological sources of this unique biology, we generated chromosome-scale genomes of two Sphagnum species: S. divinum and S. angustifolium. Sphagnum genomes show no gene colinearity with any other reference genome to date, demonstrating that Sphagnum represents an unsampled lineage of land plant evolution. The genomes also revealed an average recombination rate an order of magnitude higher than vascular land plants and short putative U/V sex chromosomes. These newly described sex chromosomes interact with autosomal loci that significantly impact growth across diverse pH conditions. This discovery demonstrates that the ability of Sphagnum to sequester carbon in acidic peat bogs is mediated by interactions between sex, autosomes and environment.
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Affiliation(s)
- Adam L Healey
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA.
| | - Bryan Piatkowski
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - John T Lovell
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Avinash Sreedasyam
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Sarah B Carey
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
- Department of Crop, Soil, and Environmental Sciences, Auburn University, Auburn, AL, USA
| | - Sujan Mamidi
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Shengqiang Shu
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Chris Plott
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Jerry Jenkins
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Travis Lawrence
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Blanka Aguero
- Department of Biology, Duke University, Durham, NC, USA
| | - Alyssa A Carrell
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | | | - Jayson Talag
- Arizona Genomics Institute, University of Arizona, Tucson, AZ, USA
| | - Aaron Duffy
- Department of Biology, Duke University, Durham, NC, USA
| | - Sara Jawdy
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Kelsey R Carter
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Lori-Beth Boston
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Teresa Jones
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | | | - Alex Harkess
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
- Department of Crop, Soil, and Environmental Sciences, Auburn University, Auburn, AL, USA
| | - Kerrie Barry
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Keykhosrow Keymanesh
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Diane Bauer
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jane Grimwood
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Lee Gunter
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Jeremy Schmutz
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - David J Weston
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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4
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Barbot E, Dufaÿ M, Tonnabel J, Godé C, De Cauwer I. On the function of flower number: disentangling fertility from pollinator-mediated selection. Proc Biol Sci 2022; 289:20221987. [PMID: 36448279 PMCID: PMC9709571 DOI: 10.1098/rspb.2022.1987] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 11/03/2022] [Indexed: 12/03/2022] Open
Abstract
In animal-pollinated angiosperms, the 'male-function' hypothesis claims that male reproductive success (RS) should benefit from large floral displays, through pollinator attraction, while female RS is expected to be mainly limited by resource availability. As appealing as this theory might be, studies comparing selection strength on flower number in both sexes rarely document the expected asymmetry. This discrepancy could arise because flower number impacts both pollinator attraction and overall gamete number. In this study, we artificially manipulate floral displays to disentangle the fertility versus pollinator attraction components of selection, both in terms of mating and RS. In females, flower number was under strong fertility selection, as predicted in the absence of pollen limitation. By contrast, in males, flower number was mainly under sexual selection, which in turn increased male RS. However, these selection patterns were not different in males with artificially increased floral displays. This suggests that sexual selection acting on flower number in males does not occur because flower number increases pollinator attraction, but rather because more pollen is available to disperse on more mates. Our study illustrates the power of disentangling various components of selection with potentially sex-specific effects for understanding the evolution of sexual dimorphism.
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Affiliation(s)
- Estelle Barbot
- Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
- ISEM, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Mathilde Dufaÿ
- CEFE, Univ. Montpellier, CNRS, Univ. Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Jeanne Tonnabel
- ISEM, Univ. Montpellier, CNRS, IRD, Montpellier, France
- CEFE, Univ. Montpellier, CNRS, Univ. Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Cécile Godé
- Univ. Lille, CNRS, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
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5
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Kwok A, Dorken ME. Sexual selection on male but not female function in monoecious and dioecious populations of broadleaf arrowhead ( Sagittaria latifolia). Proc Biol Sci 2022; 289:20220919. [PMID: 36350202 PMCID: PMC9653219 DOI: 10.1098/rspb.2022.0919] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 10/12/2022] [Indexed: 09/30/2023] Open
Abstract
Direct measures of sexual selection in plants are rare and complicated by immobility and modular growth. For plants, instantaneous measures of fitness typically scale with size, but covariances between size and mating success could obscure the detection of sexual selection. We measured the magnitude of sexual selection in a monoecious and a dioecious population of the clonal plant Sagittaria latifolia using Bateman gradients (ßss). These gradients were calculated using parentage analysis and residual regression to account for the effects of shoot and clone size on mating and reproductive success. In both populations, (i) there was greater promiscuity via male function than via female function and (ii) ßss were positive, with significant associations between mating and reproductive success for male but not female function. Moreover, estimated βss were similar for the monoecious and dioecious populations, possibly because non-overlapping female and male sex phases in hermaphroditic S. latifolia reduced the scope for interference between sex functions during mating. This study builds on previous studies of selection on plant mating traits, and of sexual selection under experimental conditions, by showing that sexual selection can operate in natural populations of plants, including populations of hermaphrodites.
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Affiliation(s)
- Allison Kwok
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada K9J 0G2
| | - Marcel E. Dorken
- Department of Biology, Trent University, Peterborough, ON, Canada K9J 0G2
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6
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Tonnabel J, David P, Pannell JR. Rapid divergence in vegetative morphology of a wind-pollinated plant between populations at contrasting densities. Evolution 2022; 76:1737-1748. [PMID: 35713285 PMCID: PMC9544426 DOI: 10.1111/evo.14539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 12/20/2021] [Accepted: 01/05/2022] [Indexed: 01/22/2023]
Abstract
Plant sexual dimorphism is thought to evolve in response to sex-specific selection associated with competition for access to mates or resources, both of which may be density dependent. In wind-pollinated plants in particular, vegetative traits such as plant size and architecture may influence resource acquisition and both pollen dispersal and receipt, with potential conflict between these two components of fitness. We evaluated the role of plant density in shaping plant traits by measuring evolutionary responses in experimental populations of the sexually dimorphic wind-pollinated plant Mercurialis annua. After three generations of evolution, we observed divergence between high- and low-density populations in several vegetative traits, whereas there was no divergence for reproductive traits. A reversal in the direction of sexually dimorphic traits expressed in young plants evolved in both low- and high-density populations compared to the original population (stored as seeds). Compared to the source population, males at high density evolved to be taller when young, whereas at low density young females tended to become smaller. These results demonstrate that a simple change in plant density can induce age-dependent and sex-specific evolution in the ontogeny of vegetative organs, and illustrates the power of experimental evolution for investigating plant trait evolution.
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Affiliation(s)
- Jeanne Tonnabel
- Department of Ecology and EvolutionUniversity of LausanneLausanneCH‐1015Switzerland,CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, FranceCNRSMontpellier34293France
| | - Patrice David
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, FranceCNRSMontpellier34293France
| | - John R. Pannell
- Department of Ecology and EvolutionUniversity of LausanneLausanneCH‐1015Switzerland
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7
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Wizenberg SB, Dang M, Campbell LG. Methods for characterizing pollen fitness in Cannabis sativa L. PLoS One 2022; 17:e0270799. [PMID: 35797371 PMCID: PMC9262209 DOI: 10.1371/journal.pone.0270799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 06/17/2022] [Indexed: 11/22/2022] Open
Abstract
Pollen grains are male gametophytes, an ephemeral haploid generation of plants, that commonly engage in competition for a limited supply of ovules. Since variation in reproductive capabilities among male gametophytes may influence the direction and pace of evolution in populations, we must be able to quantify the relative fitness of gametophytes from different sires. To explore this, we estimated the relative fitness of groups of male gametophytes in a dioecious, wind-pollinated model system, Cannabis sativa, by characterizing the non-abortion rate (measured via chemical staining) and viability (measured via in vitro germination) of pollen from multiple sires. Pollen viability quickly declined within two weeks of anther dehiscence, and pollen stored under freezer conditions did not germinate regardless of storage time. In contrast, pollen non-abortion rates declined slowly and persisted longer than the lifetime of a sporophyte plant under both room temperature and freezer conditions. Pollen samples that underwent both viability and non-abortion rate analysis displayed no significant correlation, implying that researchers cannot predict pollen viability from non-abortion rates, nor infer male gametophytic fitness from a single measure. Our work demonstrates two independent, differential approaches to measure proxies of male fitness in C. sativa.
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Affiliation(s)
- Sydney B. Wizenberg
- Department of Chemistry and Biology, Toronto Metropolitan University (recently renamed), Toronto, Ontario, Canada
| | - Michelle Dang
- Department of Chemistry and Biology, Toronto Metropolitan University (recently renamed), Toronto, Ontario, Canada
| | - Lesley G. Campbell
- Department of Chemistry and Biology, Toronto Metropolitan University (recently renamed), Toronto, Ontario, Canada
- * E-mail:
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8
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Shortlidge EE, Carey SB, Payton AC, McDaniel SF, Rosenstiel TN, Eppley SM. Microarthropod contributions to fitness variation in the common moss Ceratodon purpureus. Proc Biol Sci 2021; 288:20210119. [PMID: 33784868 PMCID: PMC8059975 DOI: 10.1098/rspb.2021.0119] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The evolution of sustained plant–animal interactions depends critically upon genetic variation in the fitness benefits from the interaction. Genetic analyses of such interactions are limited to a few model systems, in part because genetic variation may be absent or the interacting species may be experimentally intractable. Here, we examine the role of sperm-dispersing microarthropods in shaping reproduction and genetic variation in mosses. We established experimental mesocosms with known moss genotypes and inferred the parents of progeny from mesocosms with and without microarthropods, using a pooled sequencing approach. Moss reproductive rates increased fivefold in the presence of microarthropods, relative to control mesocosms. Furthermore, the presence of microarthropods increased the total number of reproducing moss genotypes, and changed the rank-order of fitness of male and female moss genotypes. Interestingly, the genotypes that reproduced most frequently did not produce sporophytes with the most spores, highlighting the challenge of defining fitness in mosses. These results demonstrate that microarthropods provide a fitness benefit for mosses, and highlight the potential for biotic dispersal agents to alter fitness among moss genotypes.
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Affiliation(s)
- Erin E Shortlidge
- Department of Biology, Portland State University, PO Box 751, Portland, OR 97202-0751, USA
| | - Sarah B Carey
- Department of Biology, University of Florida, PO Box 118525, Gainesville, FL 32611-8525, USA
| | - Adam C Payton
- Department of Biology, University of Florida, PO Box 118525, Gainesville, FL 32611-8525, USA
| | - Stuart F McDaniel
- Department of Biology, University of Florida, PO Box 118525, Gainesville, FL 32611-8525, USA
| | - Todd N Rosenstiel
- Department of Biology, Portland State University, PO Box 751, Portland, OR 97202-0751, USA
| | - Sarah M Eppley
- Department of Biology, Portland State University, PO Box 751, Portland, OR 97202-0751, USA
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9
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Tonnabel J, David P, Janicke T, Lehner A, Mollet JC, Pannell JR, Dufay M. The Scope for Postmating Sexual Selection in Plants. Trends Ecol Evol 2021; 36:556-567. [PMID: 33775429 DOI: 10.1016/j.tree.2021.02.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 11/27/2022]
Abstract
Sexual selection is known to shape plant traits that affect access to mates during the pollination phase, but it is less well understood to what extent it affects traits relevant to interactions between pollen and pistils after pollination. This is surprising, because both of the two key modes of sexual selection, male-male competition and female choice, could plausibly operate during pollen-pistil interactions where physical male-female contact occurs. Here, we consider how the key processes of sexual selection might affect traits involved in pollen-pistil interactions, including 'Fisherian runaway' and 'good-genes' models. We review aspects of the molecular and cellular biology of pollen-pistil interactions on which sexual selection could act and point to research that is needed to investigate them.
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Affiliation(s)
- Jeanne Tonnabel
- CEFE, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France.
| | - Patrice David
- CEFE, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Tim Janicke
- CEFE, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France; Applied Zoology, Technical University Dresden, Zellescher Weg 20b, 01062 Dresden, Germany
| | - Arnaud Lehner
- Normandie Univ, UNIROUEN, Laboratoire Glycobiologie et Matrice Extracellulaire Végétale (GlycoMEV), SFR 4377 NORVEGE, IRIB, Carnot I2C, 76000 Rouen, France
| | - Jean-Claude Mollet
- Normandie Univ, UNIROUEN, Laboratoire Glycobiologie et Matrice Extracellulaire Végétale (GlycoMEV), SFR 4377 NORVEGE, IRIB, Carnot I2C, 76000 Rouen, France
| | - John R Pannell
- Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland
| | - Mathilde Dufay
- CEFE, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
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10
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Carey S, Yu Q, Harkess A. The Diversity of Plant Sex Chromosomes Highlighted through Advances in Genome Sequencing. Genes (Basel) 2021; 12:381. [PMID: 33800038 PMCID: PMC8000587 DOI: 10.3390/genes12030381] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 01/21/2023] Open
Abstract
For centuries, scientists have been intrigued by the origin of dioecy in plants, characterizing sex-specific development, uncovering cytological differences between the sexes, and developing theoretical models. Through the invention and continued improvements in genomic technologies, we have truly begun to unlock the genetic basis of dioecy in many species. Here we broadly review the advances in research on dioecy and sex chromosomes. We start by first discussing the early works that built the foundation for current studies and the advances in genome sequencing that have facilitated more-recent findings. We next discuss the analyses of sex chromosomes and sex-determination genes uncovered by genome sequencing. We synthesize these results to find some patterns are emerging, such as the role of duplications, the involvement of hormones in sex-determination, and support for the two-locus model for the origin of dioecy. Though across systems, there are also many novel insights into how sex chromosomes evolve, including different sex-determining genes and routes to suppressed recombination. We propose the future of research in plant sex chromosomes should involve interdisciplinary approaches, combining cutting-edge technologies with the classics to unravel the patterns that can be found across the hundreds of independent origins.
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Affiliation(s)
- Sarah Carey
- Department of Crop, Soil, and Environmental Sciences, Auburn University, Auburn, AL 36849, USA;
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
| | - Qingyi Yu
- Texas A&M AgriLife Research, Texas A&M University System, Dallas, TX 75252, USA
| | - Alex Harkess
- Department of Crop, Soil, and Environmental Sciences, Auburn University, Auburn, AL 36849, USA;
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
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Tonnabel J, David P, Pannell JR. Do metrics of sexual selection conform to Bateman's principles in a wind-pollinated plant? Proc Biol Sci 2019; 286:20190532. [PMID: 31213181 PMCID: PMC6599987 DOI: 10.1098/rspb.2019.0532] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Bateman's principles posit that male fitness varies more, and relies more on mate acquisition, than female fitness. While Bateman's principles should apply to any organism producing gametes of variable sizes, their application to plants is potentially complicated by the high levels of polyandry suspected for plants, and by variation in the spatial distribution of prospective mates. Here we quantify the intensity of sexual selection by classical Bateman metrics using two common gardens of the wind-pollinated dioecious plant Mercurialis annua. Consistent with Bateman's principles, males displayed significantly positive Bateman gradients (a regression of fitness on mate number), whereas the reproductive success of females was independent of their ability to access mates. A large part of male fitness was explained by their mate number, which in turn was associated with males' abilities to disperse pollen. Our results suggest that sexual selection can act in plant species in much the same way as in many animals, increasing the number of mates through traits that promote pollen dispersal.
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Affiliation(s)
- Jeanne Tonnabel
- 1 Department of Ecology and Evolution, University of Lausanne , CH-1015 Lausanne , Switzerland
| | - Patrice David
- 2 Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS, UM, Université Paul Valéry Montpellier, EPHE , 1919 route de Mende, 34293 Montpellier Cedex 5 , France
| | - John R Pannell
- 1 Department of Ecology and Evolution, University of Lausanne , CH-1015 Lausanne , Switzerland
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