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Baskin JM, Baskin CC. Seed germination of gynodioecious species: theoretical considerations and a comparison of females and hermaphrodites. PLANTA 2020; 252:73. [PMID: 33025176 DOI: 10.1007/s00425-020-03472-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
Better seed germination of females than of hermaphrodites is not a major contributor to the greater geometric lifetime fitness that females require to be maintained in a gynodioecious population. Gynodioecy is a sexually dimorphic breeding system in which females (F, male sterile) and hermaphrodites (H) coexist in the same population. For plants with nuclear (biparental) inheritance of male sterility, theory predicts that except when the product of selfing rate (s) and inbreeding depression (δ) in H is high (sδ > 0.50), F must compensate (female advantage) for the loss of gene transmission via pollen production by producing more or higher-quality offspring than H to be maintained in the population. For species with cytoplasmic (maternal) inheritance of male sterility, the female requires only a small compensation in seed production or some other offspring fitness trait to persist. Reallocation to seeds of resources saved by loss of pollen production is expected to increase the quantity (number) and/or quality (mass, germinability) of seeds produced by F, thus compensating for the lack of pollen production. The primary aim of our study was to compare seed germination of F and H via a literature review. Based on theoretical considerations, we hypothesized that seeds of F should germinate better or equally as well as those of H. We found that of 235 case studies for 47 species Fgerm > Hgerm in 48.1%, Fgerm = Hgerm in 38.3% and Fgerm < Hgerm in 13.6%. Our results are very similar to those of a previously published meta-analysis that included germination of F and H for 12 species. For 162 cases on seed size, F > H in 29.0%, F = H in 63.6% and F < H in 7.4%. Since [(Fgerm > Hgerm) < (Fgerm ≤ Hgerm)] and [(Fseedsize > Hseedsize) < (Fseedsize ≤ Hseedsize)], these results suggest that seed quality is not a major fitness component of female advantage.
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Affiliation(s)
- Jerry M Baskin
- Department of Biology, University of Kentucky, Lexington, KY, 40506-0225, USA
| | - Carol C Baskin
- Department of Biology, University of Kentucky, Lexington, KY, 40506-0225, USA.
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, 40546-0312, USA.
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Hartmann FE, Snirc A, Cornille A, Godé C, Touzet P, Van Rossum F, Fournier E, Le Prieur S, Shykoff J, Giraud T. Congruent population genetic structures and divergence histories in anther‐smut fungi and their host plants
Silene italica
and the
Silene nutans
species complex. Mol Ecol 2020; 29:1154-1172. [DOI: 10.1111/mec.15387] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Fanny E. Hartmann
- Ecologie Systematique Evolution Batiment 360 AgroParisTech CNRS Universite Paris‐Saclay Orsay France
| | - Alodie Snirc
- Ecologie Systematique Evolution Batiment 360 AgroParisTech CNRS Universite Paris‐Saclay Orsay France
| | - Amandine Cornille
- Genetique Quantitative et Evolution–Le Moulon AgroParisTech CNRS INRAE Universite Paris‐Saclay Gif‐sur‐Yvette France
| | - Cécile Godé
- UMR 8198 ‐ Evo‐Eco‐Paleo CNRS Univ. Lille Lille France
| | - Pascal Touzet
- UMR 8198 ‐ Evo‐Eco‐Paleo CNRS Univ. Lille Lille France
| | - Fabienne Van Rossum
- Meise Botanic Garden Meise Belgium
- Fédération Wallonie–Bruxelles Brussels Belgium
| | | | - Stéphanie Le Prieur
- Ecologie Systematique Evolution Batiment 360 AgroParisTech CNRS Universite Paris‐Saclay Orsay France
| | - Jacqui Shykoff
- Ecologie Systematique Evolution Batiment 360 AgroParisTech CNRS Universite Paris‐Saclay Orsay France
| | - Tatiana Giraud
- Ecologie Systematique Evolution Batiment 360 AgroParisTech CNRS Universite Paris‐Saclay Orsay France
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Casimiro-Soriguer I, Buide ML, Narbona E. Diversity of sexual systems within different lineages of the genus Silene. AOB PLANTS 2015; 7:plv037. [PMID: 25862920 PMCID: PMC4433491 DOI: 10.1093/aobpla/plv037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 03/26/2015] [Indexed: 05/15/2023]
Abstract
Species and populations can be categorized by their sexual systems, depending on the spatial distribution of female and male reproductive structures within and among plants. Although a high diversity of sexual systems exists in Silene, their relative frequency at the genus and infrageneric level is unknown. Here, we carried out an extensive literature search for direct or indirect descriptions of sexual systems in Silene species. We found descriptions of sexual systems for 98 Silene species, where 63 and 35 correspond to the phylogenetically supported subgenera Silene and Behenantha, respectively. Hermaphroditism was the commonest sexual system (58.2 %), followed by dioecy (14.3 %), gynodioecy (13.3 %) and gynodioecy-gynomonoecy (i.e. hermaphroditic, female and gynomonoecious plants coexisting in the same population; 12.2 %). The presence of these sexual systems in both subgenera suggests their multiple origins. In 17 species, the description of sexual systems varied, and in most cases these differences corresponded to variations within or among populations. Interestingly, the poorly studied gynodioecy-gynomonoecy sexual system showed similar frequency to dioecy and gynodioecy in both subgenera. In addition, the incidence of gynodioecy-gynomonoecy was analysed in the species of section Psammophilae (Silene littorea, S. psammitis, S. adscendens and S. cambessedesii), in a survey of 26 populations across the distribution area of the species. The four species showed gynomonoecy-gynodioecy in most populations. Hermaphrodites were the most frequent morph, with a low number of females and gynomonoecious plants in all populations. The frequency of sexual morphs varied significantly among the studied populations but not among species. Female plants generally produced smaller numbers of flowers than hermaphroditic or gynomonoecious plants, and the percentages of female flowers per population were low. All these findings suggest that the gynodioecious-gynomonoecious sexual system in section Psammophilae is closer to hermaphroditism or gynomonoecy than gynodioecy.
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Affiliation(s)
- Inés Casimiro-Soriguer
- Área de Botánica, Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Ctra. de Utrera, km 1, 41013 Sevilla, Spain Área de Botánica, Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Avenida Reina Mercedes s/n, 41012 Sevilla, Spain
| | - Maria L Buide
- Área de Botánica, Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Ctra. de Utrera, km 1, 41013 Sevilla, Spain
| | - Eduardo Narbona
- Área de Botánica, Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Ctra. de Utrera, km 1, 41013 Sevilla, Spain
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Ghadge AG, Karmakar K, Devani RS, Banerjee J, Mohanasundaram B, Sinha RK, Sinha S, Banerjee AK. Flower development, pollen fertility and sex expression analyses of three sexual phenotypes of Coccinia grandis. BMC PLANT BIOLOGY 2014; 14:325. [PMID: 25430000 PMCID: PMC4255441 DOI: 10.1186/s12870-014-0325-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 11/06/2014] [Indexed: 05/07/2023]
Abstract
BACKGROUND Coccinia grandis is a dioecious species of Cucurbitaceae having heteromorphic sex chromosomes. The chromosome constitution of male and female plants is 22 + XY and 22 + XX respectively. Y chromosome of male sex is conspicuously large and plays a decisive role in determining maleness. Sex modification has been studied in hypogynous Silene latifolia (Caryophyllaceae) but there is no such report in epigynous Coccinia grandis. Moreover, the role of organ identity genes during sex expression in Coccinia has not been evaluated earlier. Investigations on sexual phenotypes of C. grandis including a rare gynomonoecious (GyM) form and AgNO3 mediated sex modification have added a new dimension to the understanding of sex expression in dioecious flowering plants. RESULTS Morphometric analysis showed the presence of staminodes in pistillate flowers and histological study revealed the absence of carpel initials in male flowers. Though GyM plant had XX sex chromosomes, the development of stamens occurred in hermaphrodite flowers but the pollens were not fertile. Silver nitrate (AgNO3) application enhanced stamen growth in wild type female flowers like that of GyM plant but here also the pollens were sterile. Differential expression of CgPI could be involved in the development of different floral phenotypes. CONCLUSIONS The three principle factors, Gynoecium Suppression (SuF), Stamen Promoting Factor (SPF) and Male Fertility (mF) that control sex expression in dioecious C. grandis assumed to be located on Y chromosome, play a decisive role in determining maleness. However, the characteristic development of stamens in hermaphrodite flowers of GyM plant having XX sex chromosomes indicates that Y-linked SPF regulatory pathway is somehow bypassed. Our experimental findings together with all other previous chromosomal and molecular cytogenetical data strongly support the view that C. grandis could be used as a potential model system to study sex expression in dioecious flowering plant.
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Affiliation(s)
- Amita G Ghadge
- />Indian Institute of Science Education and Research (IISER Pune), 900 NCL Innovation Park, Dr. Homi Bhabha road, Pune, 411 008 Maharashtra India
| | - Kanika Karmakar
- />Department of Botany, Tripura University, Suryamaninagar, Tripura 799 022 India
| | - Ravi S Devani
- />Indian Institute of Science Education and Research (IISER Pune), 900 NCL Innovation Park, Dr. Homi Bhabha road, Pune, 411 008 Maharashtra India
| | - Jayeeta Banerjee
- />Indian Institute of Science Education and Research (IISER Pune), 900 NCL Innovation Park, Dr. Homi Bhabha road, Pune, 411 008 Maharashtra India
| | - Boominathan Mohanasundaram
- />Indian Institute of Science Education and Research (IISER Pune), 900 NCL Innovation Park, Dr. Homi Bhabha road, Pune, 411 008 Maharashtra India
| | - Rabindra K Sinha
- />Department of Botany, Tripura University, Suryamaninagar, Tripura 799 022 India
| | - Sangram Sinha
- />Department of Botany, Tripura University, Suryamaninagar, Tripura 799 022 India
| | - Anjan K Banerjee
- />Indian Institute of Science Education and Research (IISER Pune), 900 NCL Innovation Park, Dr. Homi Bhabha road, Pune, 411 008 Maharashtra India
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Varga S, Kytöviita MM. Variable mycorrhizal benefits on the reproductive output of Geranium sylvaticum, with special emphasis on the intermediate phenotype. PLANT BIOLOGY (STUTTGART, GERMANY) 2014; 16:306-314. [PMID: 23870051 DOI: 10.1111/plb.12050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 04/19/2013] [Indexed: 06/02/2023]
Abstract
In several gynodioecious species, intermediate sex between female and hermaphrodite has been reported, but few studies have investigated fitness parameters of this intermediate phenotype. Here, we examined the interactions between plant sex and arbuscular mycorrhizal (AM) fungal species affecting the reproductive output of Geranium sylvaticum, a sexually polymorphic plant species with frequent intermediate sexes between females and hermaphrodites, using a common garden experiment. Flowering phenology, AM colonisation levels and several plant vegetative and reproductive parameters, including seed and pollen production, were measured. Differences among sexes were detected in flowering, fruit set, pollen production and floral size. The two AM species used in the present work had different effects on plant fitness parameters. One AM species increased female fitness through increasing seed number and seed mass, while the other species reduced seed mass in all sexes investigated. AM fungi did not affect intermediate and hermaphrodite pollen content in anthers. The three sexes in G. sylvaticum did not differ in their reproductive output in terms of total seed production, but hermaphrodites had potentially larger fathering ability than intermediates due to higher anther number. The ultimate female function--seed production--did not differ among the sexes, but one of the AM fungi used potentially decreased host plant fitness. In addition, in the intermediate sex, mycorrhizal symbiosis functioned similarly in females as in hermaphrodites.
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Affiliation(s)
- S Varga
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
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Casimiro-Soriguer I, Buide ML, Narbona E. The roles of female and hermaphroditic flowers in the gynodioecious-gynomonoecious Silene littorea: insights into the phenology of sex expression. PLANT BIOLOGY (STUTTGART, GERMANY) 2013; 15:941-7. [PMID: 23174011 DOI: 10.1111/j.1438-8677.2012.00697.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 09/28/2012] [Indexed: 05/23/2023]
Abstract
Some gynodioecious species have intermediate individuals that bear both female and hermaphroditic flowers. This phenomenon is known as a gynodioecious-gynomonoecious sexual system. Gender expression in such species has received little attention in the past, and the phenologies of male and female functions have also yet to be explored. In this study, we examined variations in gender patterns, their effects on female reproductive success and sex expression in depth throughout the flowering period in two populations. The studied populations of Silene littorea contained mostly gynomonoecious plants and the number of pure females was very low. The gynomonoecious plants showed high variability in the total proportion of female flowers. In addition, the proportion of female flowers in each plant varied widely across the flowering season. Although there was a trend towards maleness, our measures of functional gender suggested that most plants transmit their genes via both pollen and ovules. Fruit set and seed set were not significantly different among populations; in contrast, flower production significantly varied between the two populations - and among plants - with consequent variation in total seed production. Conversely, gender and sex expression were similar in both populations. Plants with higher phenotypic femaleness did not have higher fruit set, seed set or total female fecundity. The mating environment fluctuated little across the flowering period, but fluctuations were higher in the population with low flower production. We therefore conclude that the high proportion of gynomonoecious individuals in our studied populations of S. littorea may be advantageous for the species, providing the benefits of both hermaphroditic and female flowers.
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Affiliation(s)
- I Casimiro-Soriguer
- Área de Botánica, Dpto. Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Sevilla, Spain; Área de Botánica, Dpto. de Biología Vegetal y Ecología, Universidad de Sevilla, Sevilla, Spain
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Dufay M, Billard E. How much better are females? The occurrence of female advantage, its proximal causes and its variation within and among gynodioecious species. ANNALS OF BOTANY 2012; 109:505-19. [PMID: 21459860 PMCID: PMC3278283 DOI: 10.1093/aob/mcr062] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 02/10/2011] [Indexed: 05/09/2023]
Abstract
BACKGROUND Gynodioecy is a reproductive system of interest for evolutionary biologists, as it poses the question of how females can be maintained while competing with hermaphrodites that possess both male and female functions. One necessary condition for the maintenance of this polymorphism is the occurrence of a female advantage, i.e. a better seed production or quality by females compared with hermaphrodites. Theoretically, its magnitude can be low when sterility mutations are cytoplasmic, while a 2-fold advantage is needed in the case of nuclear sterility. Such a difference is often thought to be due to reduced inbreeding depression in obligatory outcrossed females. Finally, variation in sex ratio and female advantage occur among populations of some gynodioecious species, though the prevalence of such variation is unknown. SCOPE By reviewing and analysing the data published on 48 gynodioecious species, we examined three important issues about female advantage. (1) Are reduced selfing and inbreeding depression likely to be the major cause of female advantage? (2) What is the magnitude of female advantage and does it fit theoretical predictions? (3) Does the occurrence or the magnitude of female advantage vary among populations within species and why? CONCLUSIONS It was found that a female advantage occurred in 40 species, with a magnitude comprised between 1 and 2 in the majority of cases. In many species, reduced selfing may not be a necessary cause of this advantage. Finally, female advantage varied among populations in some species, but both positive and negative correlations were found with female frequency. The role of reduced selfing in females for the evolution of gynodioecy, as well as the various processes that affect sex ratios and female advantage in populations are discussed.
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Affiliation(s)
- Mathilde Dufay
- Laboratoire GEPV FRE-CNRS 3268, Université des Sciences et Technologies de Lille - Lille 1, Villeneuve d'Ascq Cedex, France.
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Collin CL, Penet L, Shykoff JA. Early inbreeding depression in the sexually polymorphic plant Dianthus sylvestris (Caryophyllaceae): Effects of selfing and biparental inbreeding among sex morphs. AMERICAN JOURNAL OF BOTANY 2009; 96:2279-2287. [PMID: 21622343 DOI: 10.3732/ajb.0900073] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Predominantly outcrossing plant species are expected to accumulate recessive deleterious mutations, which can be purged when in a homozygous state following selfing. Individuals may vary in their genetic load because of different selfing histories, which could lead to differences in inbreeding depression among families. Lineage-dependent inbreeding depression can appear in gynodioecious species if obligatory outcrossed females are more likely to produce female offspring and if partially selfing hermaphrodites are more likely to produce hermaphrodites. We investigated inbreeding depression at the zygote, seed, and germination stages in the gynomonoecious-gynodioecious Dianthus sylvestris, including pure-sexed plants and a mixed morph. We performed hand-pollinations on 56 plants, belonging to the three morphs, each receiving 2-3 cross treatments (out-, sib- and self-pollination) on multiple flowers. Effects of cross treatments varied among stages and influenced seed provisioning, with sibling competition mainly occurring within outcrossed fruits. We found significant inbreeding depression for seed mass and germination and cumulative early inbreeding depression varied greatly among families. Among sex morphs, we found that females and hermaphrodites differed in biparental inbreeding depression, whereas uniparental was similar for all. Significant inbreeding depression levels may play a role in female maintenance in this species, and individual variation in association with sex-lineages proclivity is discussed.
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Affiliation(s)
- Carine L Collin
- Université Paris-Sud, Laboratoire Ecologie, Systématique et Evolution, UMR 8079, Orsay cedex, F-91405, France; CNRS, UMR 8079, Orsay cedex, F-91405, France
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