1
|
Soininen JOS, Kytöviita M. Geranium sylvaticum increases pollination probability by sexually dimorphic flowers. Ecol Evol 2022; 12:e9670. [PMID: 36590340 PMCID: PMC9797467 DOI: 10.1002/ece3.9670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 12/10/2022] [Indexed: 12/29/2022] Open
Abstract
Sexual dimorphism is expressed as different morphologies between the sexes of a species. Dimorphism is pronounced in gynodioecious populations which consist of female and hermaphrodite individuals. The small size of female flowers in gynodioecious species is often explained by resource re-allocation to seed production instead of large flowers. However, pollinator attraction is critical to female fitness, and factors other than resource savings are needed to explain the small size of female flowers. We hypothesized that the floral size dimorphism in the perennial gynodioecious Geranium sylvaticum (L.) is adaptive in terms of pollination. To test this "pollination hypothesis," we video recorded the small female and large hermaphrodite G. sylvaticum flowers. We parameterized floral visitor behavior when visiting a flower and calculated pollination probabilities by a floral visitor as the probability of touching anther and stigma with the same body part. Pollination probability differed in terms of flower sex and pollinator species. Bumblebees had the highest pollination probability. The small female flowers were more likely to receive pollen via several pollinator groups than the large hermaphrodite flowers. The pollen display of hermaphrodites matched poorly with the stigma display of hermaphrodites, but well with that of females. Although the small size of female flowers is commonly explained by resource re-allocation, we show that sexual dimorphism in flower size may increase the main reproductive functions of the females and hermaphrodites. Dimorphism increases pollination probability in females and fathering probability of the hermaphrodites likely driving G. sylvaticum populations towards dioecy.
Collapse
Affiliation(s)
- Jaakko O. S. Soininen
- Department of Biological and Environmental Sciences, Faculty of Mathematics and ScienceUniversity of JyväskyläJyväskyläFinland
| | - Minna‐Maarit Kytöviita
- Department of Biological and Environmental Sciences, Faculty of Mathematics and ScienceUniversity of JyväskyläJyväskyläFinland
| |
Collapse
|
2
|
Ramstack Hobbs JM, Garthwaite IJ, Lancaster L, Moffett‐Dobbs J, Johnson K, Criss N, McConathy V, James CA, Gipe A, Claeson SM, LeRoy CJ. The influence of weevil herbivory on leaf litter chemistry in dioecious willows. Ecol Evol 2022; 12:e9626. [PMID: 36514546 PMCID: PMC9731909 DOI: 10.1002/ece3.9626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 11/21/2022] [Accepted: 11/24/2022] [Indexed: 12/13/2022] Open
Abstract
Leaf litter inputs can influence the structure and function of both terrestrial and adjacent aquatic ecosystems. Dioecy and herbivory are two factors that together have received little attention, yet have the potential to affect the quantity, quality, and timing of riparian litterfall, litter chemistry, and litter decomposition processes. Here, we explore litter chemistry differences for the dioecious Sitka willow (Salix sitchensis Sanson ex. Bong), which is establishing on primary successional habitats at Mount St. Helens (WA, USA) and is heavily infested with a stem-boring weevil (Cryptorhynchus lapathi). Weevil-attacked branches produced summer senesced litter that had significantly higher %N, lower C:N ratios, and lower condensed tannins than litter from branches that were unattacked by the weevil and senesced naturally in the autumn. Weevils more often attack female willows; however, these common litter chemicals did not significantly differ between males and females within the weevil-attacked and -unattacked groups. High-resolution mass spectrometry was used to isolate compounds in litter from 10 Sitka willow individuals with approximately 1500-1600 individual compounds isolated from each sample. There were differences between weevil-attacked litter and green leaf samples, but at this level, there was no clustering of male and female samples. However, further exploration of the isolated compounds determined a suite of compounds present only in either males or females. These findings suggest some variation in more complex litter chemistry between the sexes, and that significant differences in weevil-attacked litter chemistry, coupled with the shift in seasonality of litter inputs to streams, could significantly affect in-stream ecological processes, such as decomposition and detritivore activity.
Collapse
Affiliation(s)
- Joy M. Ramstack Hobbs
- The Evergreen State College, Environmental Studies ProgramOlympiaWashingtonUSA,St. Croix Watershed Research Station, Science Museum of MinnesotaMarine on St. CroixMinnesotaUSA
| | - Iris J. Garthwaite
- The Evergreen State College, Environmental Studies ProgramOlympiaWashingtonUSA
| | - Logan Lancaster
- The Evergreen State College, Environmental Studies ProgramOlympiaWashingtonUSA
| | | | - Kelly Johnson
- The Evergreen State College, Environmental Studies ProgramOlympiaWashingtonUSA
| | - Nichole Criss
- The Evergreen State College, Environmental Studies ProgramOlympiaWashingtonUSA
| | - Victoria McConathy
- The Evergreen State College, Environmental Studies ProgramOlympiaWashingtonUSA
| | - C. Andrew James
- Center for Urban WatersUniversity of Washington TacomaTacomaWashingtonUSA
| | - Alex Gipe
- Center for Urban WatersUniversity of Washington TacomaTacomaWashingtonUSA,Washington State Department of EcologyLaceyWashingtonUSA
| | | | - Carri J. LeRoy
- The Evergreen State College, Environmental Studies ProgramOlympiaWashingtonUSA
| |
Collapse
|
3
|
Wang L, Tang Z. How do arbuscular mycorrhizas affect reproductive functional fitness of host plants? FRONTIERS IN PLANT SCIENCE 2022; 13:975488. [PMID: 36072330 PMCID: PMC9441947 DOI: 10.3389/fpls.2022.975488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
Arbuscular mycorrhizal (AM) symbiosis in soil may be directly or indirectly involved in the reproductive process of sexually reproducing plants (seed plants), and affect their reproductive fitness. However, it is not clear how underground AM symbiosis affects plant reproductive function. Here, we reviewed the studies on the effects of AM symbiosis on plant reproductive fitness including both male function (pollen) and female function (seed). AM symbiosis regulates the development and function of plant sexual organs by affecting the nutrient using strategy and participating in the formation of hormone networks and secondary compounds in host plants. The nutrient supply (especially phosphorus supply) of AM symbiosis may be the main factor affecting plant's reproductive function. Moreover, the changes in hormone levels and secondary metabolite content induced by AM symbiosis can also affect host plants reproductive fitness. These effects can occur in pollen formation and transport, pollen tube growth and seed production, and seedling performance. Finally, we discuss other possible effects of AM symbiosis on the male and female functional fitness, and suggest several additional factors that may be involved in the influence of AM symbiosis on the reproductive fitness of host plants. We believe that it is necessary to accurately identify and verify the mechanisms driving the changes of reproductive fitness of host plant in symbiotic networks in the future. A more thorough understanding of the mechanism of AM symbiosis on reproductive function will help to improve our understanding of AM fungus ecological roles and may provide references for improving the productivity of natural and agricultural ecosystems.
Collapse
|
4
|
Chitty RP, Gange AC. Aphids and Mycorrhizal Fungi Shape Maternal Effects in Senecio vulgaris. PLANTS 2022; 11:plants11162150. [PMID: 36015453 PMCID: PMC9415133 DOI: 10.3390/plants11162150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/12/2022] [Accepted: 08/17/2022] [Indexed: 11/29/2022]
Abstract
Plant performance in any one generation is affected not only by the prevailing environmental conditions, but also by the conditions experienced by the parental generation of those plants. These maternal effects have been recorded in a many plant species, but the influence of external biotic (as opposed to abiotic) factors on shaping maternal effects have been rarely examined. Furthermore, almost all previous studies have taken place over one plant generation, rather than across multiple generations. Here, we studied the influence of insect herbivory and arbuscular mycorrhizal (AM) fungal colonisation on the shaping of maternal effects in the annual forb Senecio vulgaris. We grew plants with and without aphids (Myzus persicae) and AM fungi (hereafter termed ‘induction events’) over four successive generations, wherein seeds from plants in any one treatment were used to grow plants of the same treatment in the next generation, all in identical environmental conditions. We found strong evidence of maternal effects in the second plant generation, i.e., after one induction event. These plants took longer to germinate, flowered in a shorter time, produced lighter seeds and were shorter and of lower biomass than their parents. Aphid attack tended to enhance these effects, whereas AM fungi had little influence. However, thereafter there was a gradual recovery in these parameters, so that plants experiencing three inductions showed similar life history parameters to those in the original generation. We conclude that experiments investigating maternal effects need to be performed over multiple plant generations and that biotic factors such as insects and mycorrhizas must also be taken into account, along with abiotic factors, such as nutrient and water availability.
Collapse
Affiliation(s)
- Ruth P. Chitty
- Tree Health Diagnostic & Advisory Service, Forest Research, Alice Holt Lodge, Farnham, Surrey GU10 4LH, UK
- Correspondence: ; Tel.: +44-(0)300-067-5724
| | - Alan C. Gange
- Department of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK
| |
Collapse
|
5
|
He Y, Xu H, Liu H, Luo M, Chu C, Fang S. Sexual competition and kin recognition co-shape the traits of neighboring dioecious Diospyros morrisiana seedlings. HORTICULTURE RESEARCH 2021; 8:162. [PMID: 34193863 PMCID: PMC8245536 DOI: 10.1038/s41438-021-00598-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 05/10/2021] [Accepted: 05/15/2021] [Indexed: 06/08/2023]
Abstract
Plants respond differently to the identity of their neighbors, such as their sex and kinship, showing plasticity in their traits. However, how the functional traits of dioecious trees are shaped by the recognition of neighbors with different sex and kinship remains unknown. In this study, we set up an experiment with different kin/nonkin and inter/intrasexual combinations for a dioecious tree species, Diospyros morrisiana. The results showed that plants grew better with nonkin and intrasexual neighbors than with kin and intersexual neighbors. Kin combinations had significantly shorter root length in the resource-overlapping zone than nonkin combinations, suggesting that kin tended to reduce competition by adjusting their root distribution, especially among female siblings. Our study suggested that the seedling growth of D. morrisiana was affected by both the relatedness and sexual identity of neighboring plants. Further analysis by gas chromatography-mass spectrometry showed that the root exudate composition of female seedlings differed from that of male seedlings. Root exudates may play important roles in sex competition in dioecious plants. This study indicates that sex-specific competition and kin recognition interact and co-shape the traits of D. morrisiana seedlings, while intrasexual and nonkin neighbors facilitate the growth of seedlings. Our study implies that kin- and sex-related interactions depend on different mechanisms, kin selection, and niche partitioning, respectively. These results are critical for understanding how species coexist and how traits are shaped in nature.
Collapse
Affiliation(s)
- Yulin He
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Han Xu
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, 510520, China
| | - Hanlun Liu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Meiling Luo
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Chengjin Chu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Suqin Fang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
| |
Collapse
|
6
|
Rutkowska J, Lagisz M, Bonduriansky R, Nakagawa S. Mapping the past, present and future research landscape of paternal effects. BMC Biol 2020; 18:183. [PMID: 33246472 PMCID: PMC7694421 DOI: 10.1186/s12915-020-00892-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 10/08/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Although in all sexually reproducing organisms an individual has a mother and a father, non-genetic inheritance has been predominantly studied in mothers. Paternal effects have been far less frequently studied, until recently. In the last 5 years, research on environmentally induced paternal effects has grown rapidly in the number of publications and diversity of topics. Here, we provide an overview of this field using synthesis of evidence (systematic map) and influence (bibliometric analyses). RESULTS We find that motivations for studies into paternal effects are diverse. For example, from the ecological and evolutionary perspective, paternal effects are of interest as facilitators of response to environmental change and mediators of extended heredity. Medical researchers track how paternal pre-fertilization exposures to factors, such as diet or trauma, influence offspring health. Toxicologists look at the effects of toxins. We compare how these three research guilds design experiments in relation to objects of their studies: fathers, mothers and offspring. We highlight examples of research gaps, which, in turn, lead to future avenues of research. CONCLUSIONS The literature on paternal effects is large and disparate. Our study helps in fostering connections between areas of knowledge that develop in parallel, but which could benefit from the lateral transfer of concepts and methods.
Collapse
Affiliation(s)
- Joanna Rutkowska
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, BEES, The University of New South Wales, Sydney, Australia
| | - Malgorzata Lagisz
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, BEES, The University of New South Wales, Sydney, Australia
| | - Russell Bonduriansky
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, BEES, The University of New South Wales, Sydney, Australia
| | - Shinichi Nakagawa
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, BEES, The University of New South Wales, Sydney, Australia
| |
Collapse
|
7
|
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.
Collapse
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.
| |
Collapse
|
8
|
Genre A, Lanfranco L, Perotto S, Bonfante P. Unique and common traits in mycorrhizal symbioses. Nat Rev Microbiol 2020; 18:649-660. [PMID: 32694620 DOI: 10.1038/s41579-020-0402-3] [Citation(s) in RCA: 178] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2020] [Indexed: 12/16/2022]
Abstract
Mycorrhizas are among the most important biological interkingdom interactions, as they involve ~340,000 land plants and ~50,000 taxa of soil fungi. In these mutually beneficial interactions, fungi receive photosynthesis-derived carbon and provide the host plant with mineral nutrients such as phosphorus and nitrogen in exchange. More than 150 years of research on mycorrhizas has raised awareness of their biology, biodiversity and ecological impact. In this Review, we focus on recent phylogenomic, molecular and cell biology studies to present the current state of knowledge of the origin of mycorrhizal fungi and the evolutionary history of their relationship with land plants. As mycorrhizas feature a variety of phenotypes, depending on partner taxonomy, physiology and cellular interactions, we explore similarities and differences between mycorrhizal types. During evolution, mycorrhizal fungi have refined their biotrophic capabilities to take advantage of their hosts as food sources and protective niches, while plants have developed multiple strategies to accommodate diverse fungal symbionts. Intimate associations with pervasive ecological success have originated at the crossroads between these two evolutionary pathways. Our understanding of the biological processes underlying these symbioses, where fungi act as biofertilizers and bioprotectors, provides the tools to design biotechnological applications addressing environmental and agricultural challenges.
Collapse
Affiliation(s)
- Andrea Genre
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Luisa Lanfranco
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Silvia Perotto
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Paola Bonfante
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy.
| |
Collapse
|
9
|
LeRoy CJ, Ramstack Hobbs JM, Claeson SM, Moffett J, Garthwaite I, Criss N, Walker L. Plant sex influences aquatic–terrestrial interactions. Ecosphere 2020. [DOI: 10.1002/ecs2.2994] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Carri J. LeRoy
- The Evergreen State College Environmental Studies Program Olympia Washington 98505 USA
| | - Joy M. Ramstack Hobbs
- The Evergreen State College Environmental Studies Program Olympia Washington 98505 USA
- St. Croix Watershed Research Station Science Museum of Minnesota Marine on St. Croix Minnesota 55047 USA
| | | | - Jordan Moffett
- The Evergreen State College Environmental Studies Program Olympia Washington 98505 USA
| | - Iris Garthwaite
- The Evergreen State College Environmental Studies Program Olympia Washington 98505 USA
| | - Nichole Criss
- The Evergreen State College Environmental Studies Program Olympia Washington 98505 USA
| | - Lauren Walker
- Lewis and Clark College College of Arts and Sciences Portland Oregon 97219 USA
| |
Collapse
|
10
|
Varga S, Soulsbury CD. Paternal arbuscular mycorrhizal fungal status affects DNA methylation in seeds. Biol Lett 2017; 13:rsbl.2017.0407. [PMID: 28931731 DOI: 10.1098/rsbl.2017.0407] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 08/29/2017] [Indexed: 11/12/2022] Open
Abstract
Most land plants grow in association with arbuscular mycorrhizal fungi (AMF) in their roots and these fungi can cause transgenerational effects on plants' offspring. These may be caused by changes in DNA methylation of the offspring. In this study, we compared the amount of global DNA methylation in seeds of the gynodioecious plant Geranium sylvaticum in relation to the gender and the AMF status of the parents producing the seeds. The amount of DNA methylated was positively related to seed mass. Seeds produced by females had a similar proportion of methylated DNA regardless of the AMF status of the father siring the seed. By contrast, seeds from hermaphrodites had higher DNA methylation when sired by AMF fathers. We show to the best of our knowledge for the first time, that the AMF status of fathers can affect DNA methylation in seeds and that these changes in DNA methylation are further dependent on the gender of the mother producing the seeds.
Collapse
Affiliation(s)
- Sandra Varga
- School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Lincoln LN6 7TS, UK
| | - Carl D Soulsbury
- School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Lincoln LN6 7TS, UK
| |
Collapse
|
11
|
Slate ML, Rosenstiel TN, Eppley SM. Sex-specific morphological and physiological differences in the moss Ceratodon purpureus (Dicranales). ANNALS OF BOTANY 2017; 120:845-854. [PMID: 28981564 PMCID: PMC5714240 DOI: 10.1093/aob/mcx071] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 05/15/2017] [Indexed: 05/07/2023]
Abstract
BACKGROUND AND AIMS Dioecy and sexual dimorphism occur in many terrestrial plant species but are especially widespread among the bryophytes. Despite the prevalence of dioecy in non-vascular plants, surprisingly little is known about how fine-scale sex-specific cell and leaf morphological traits are correlated with sex-specific physiology and population sex ratios. Such data are critical to understanding the inter-relationship between sex-specific morphological and physiological characters and how their relationship influences population structure. In this study, these data types were assessed to determine how they vary across three populations within one moss species and whether fine-scale morphological traits scale up to physiological and sex ratio characteristics. METHODS Twenty cell-, leaf- and canopy-level traits and two photochemical measurements were compared between sexes and populations of the dioecious moss Ceratodon purpureus . Field population-expressed sex ratios were obtained for the same populations. KEY RESULTS Male and female plants differed in cell, leaf and photochemical measures. These sexual dimorphisms were female biased, with females having larger and thicker leaves and greater values for chlorophyll fluorescence-based, leaf photochemistry measurements than males. Female traits were also more variable than male traits. Interestingly, field population sex ratios were significantly male biased in two study populations and female biased in the third study population. CONCLUSIONS The results demonstrate that the larger morphology and the greater physiological output of female C. purpureus gametophytes compared with males occurs across populations and is likely to have significant effects on resource allocation and biotic interactions. However, this high level of dimorphism does not explain population sex ratio variation in the three study populations tested. This research lays the groundwork for future studies on how differential sex-specific variation in cell and leaf traits influences bryophyte plant fitness.
Collapse
Affiliation(s)
- Mandy L Slate
- Portland State University, Center for Life in Extreme Environments and Department of Biology, PO Box 751, Portland, OR 97202-0751, USA
| | - Todd N Rosenstiel
- Portland State University, Center for Life in Extreme Environments and Department of Biology, PO Box 751, Portland, OR 97202-0751, USA
| | - Sarah M Eppley
- Portland State University, Center for Life in Extreme Environments and Department of Biology, PO Box 751, Portland, OR 97202-0751, USA
- For correspondence. E-mail
| |
Collapse
|
12
|
Marks RA, Smith JJ, Cronk Q, McLetchie DN. Variation in the bacteriome of the tropical liverwort, Marchantia inflexa, between the sexes and across habitats. Symbiosis 2017. [DOI: 10.1007/s13199-017-0522-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
13
|
Krieg C, Watkins JE, Chambers S, Husby CE. Sex-specific differences in functional traits and resource acquisition in five cycad species. AOB PLANTS 2017; 9:013. [PMID: 28533896 PMCID: PMC5420813 DOI: 10.1093/aobpla/plx013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 03/22/2017] [Accepted: 04/03/2017] [Indexed: 05/16/2023]
Abstract
Selective pressures acting on plant life histories can drive extreme specialization. One example of such specialization is the evolution of dioecious breeding systems. Evolutionary and ecological theory posits that dioecy may subject male and female individuals to different selective pressures and result in unique sex-mediated adaptive traits related to resource allocation and ecophysiology. Cycads are the earliest diverging lineage of seed plants with strict dioecy, yet we know almost nothing about the ecology and physiology of this group. Especially limited is our understanding of potential sex-specific differences and how such differences may influence species ecology. Here we examine the ecophysiology of male and female cycads to understand better, the role that dioecy plays in this group. We evaluated sex-specific differences in ecophysiological traits and resource acquisition in five species. Specifically, we compared photosynthetic physiology, nitrogen and carbon content, isotope discrimination (δ15N and δ13C), and stomatal density. In some cycads, (i) males and females have similar investments in leaf nitrogen but females exhibit greater incorporation of nitrogen from nitrogen-fixing soil bacteria, (ii) males display higher photosynthetic capacity but females show decreased [corrected] water-use efficiency, and (iii) males have higher stomatal conductance but similar stomatal density to females. This study is the first to examine the ecophysiological differences that have evolved in the oldest dioecious lineage of seed-bearing plants. Our results show unexpected differences in photosynthetic physiology and highlight the co-evolution with nitrogen fixing soil bacteria as a potential new key player in an old lineage.
Collapse
Affiliation(s)
- Christopher Krieg
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - James E. Watkins
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
| | - Sally Chambers
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Chad E. Husby
- Montgomery Botanical Centre, Miami, FL 33156, USA
- Present address: Fairchild Tropical Botanic Garden, Miami, FL 33156, USA
| |
Collapse
|
14
|
Varga S, Kytöviita MM. Light availability affects sex lability in a gynodioecious plant. AMERICAN JOURNAL OF BOTANY 2016; 103:1928-1936. [PMID: 27864260 DOI: 10.3732/ajb.1600158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 10/27/2016] [Indexed: 06/06/2023]
Abstract
PREMISE OF THE STUDY Sex lability (i.e., gender diphasy) in plants is classically linked to the larger resource needs associated with the female sexual function (i.e., seed production) compared to the male function (i.e., pollen production). Sex lability in response to the environment is extensively documented in dioecious species, but has been largely overlooked in gynodioecious plants. METHODS Here, we tested whether environmental conditions induce sex lability in the gynodioecious Geranium sylvaticum. We conducted a transplantation experiment in the field where plants with different sex expression were reciprocally transplanted between high light and low light habitats. We measured plants' reproductive output and sex expression over four years. KEY RESULTS Our results show that sex expression was labile over the study period. The light level at the destination habitat had a significant effect on sexual expression and reproductive output, because plants decreased their reproductive output when transplanted to the low light habitat. Transplantation origin did not affect any parameter measured. CONCLUSIONS This study shows that sex expression in Geranium sylvaticum is labile and related to light availability. Sexually labile plants did not produce more seeds or pollen, and thus, there was no apparent fitness gain in sexually labile individuals. Sex lability in gynodioecious plants may be more common than previously believed because detection of sex lability necessitates data on the same individuals over time, which is rare in sexually dimorphic herbaceous plants.
Collapse
Affiliation(s)
- Sandra Varga
- Department of Biological and Environmental Science, University of Jyvaskyla, P.O. Box 35 40014 Jyvaskyla, Finland
| | - Minna-Maarit Kytöviita
- Department of Biological and Environmental Science, University of Jyvaskyla, P.O. Box 35 40014 Jyvaskyla, Finland
| |
Collapse
|
15
|
Vivas M, Kemler M, Slippers B. Maternal effects on tree phenotypes: considering the microbiome. TRENDS IN PLANT SCIENCE 2015; 20:541-544. [PMID: 26124001 DOI: 10.1016/j.tplants.2015.06.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 06/03/2015] [Accepted: 06/07/2015] [Indexed: 06/04/2023]
Abstract
The biotic and abiotic environmental experience of plants can influence the offspring without any changes in DNA sequence. These effects can modulate the development of the progeny and their interaction with microorganisms. This interaction includes fungal endophytic communities which have significant effects on trees and their associated ecosystems. In this opinion article, we highlight potential maternal mechanisms through which endophytes could influence the progeny. We argue that a better understanding of these interactions might help to predict the response of trees to stress conditions and enhance the efficiency of tree breeding programs.
Collapse
Affiliation(s)
- Maria Vivas
- Department of Genetics, Forestry, and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa.
| | - Martin Kemler
- Department of Genetics, Forestry, and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa
| | - Bernard Slippers
- Department of Genetics, Forestry, and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa
| |
Collapse
|
16
|
Varga S. Effects of arbuscular mycorrhizal fungi and maternal plant sex on seed germination and early plant establishment. AMERICAN JOURNAL OF BOTANY 2015; 102:358-366. [PMID: 25784469 DOI: 10.3732/ajb.1400361] [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] [Indexed: 06/04/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY Arbuscular mycorrhizal fungi usually enhance overall plant performance, yet their effects on seed germination and early plant establishment, crucial steps in plant cycles, are generally overlooked. In gynodioecious species, sexual dimorphism in these traits has been reported, with females producing seeds that germinate at a faster rate than seeds from hermaphrodites.• METHODS Using the gynodioecious plant Geranium sylvaticum, I investigated in a greenhouse experiment whether the presence of arbuscular mycorrhizal spores affects seed germination and early plant establishment, examining at the same time whether the sex of the mother producing the seeds also influences these parameters and whether sex-specific interactions between these two factors exist.• KEY RESULTS The presence of arbuscular mycorrhizal spores in the soil decreased seed germination, did not affect plant survival, but did increase plant growth. Moreover, no significant differences in seed traits were detected between the sexes of the plants producing the seeds.• CONCLUSIONS This study demonstrates that arbuscular mycorrhizal fungi may have contrasting effects for plants during early life stages and that mycorrhizal effects can take place even at the precolonization stage.
Collapse
Affiliation(s)
- Sandra Varga
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| |
Collapse
|
17
|
Selosse MA, Bessis A, Pozo MJ. Microbial priming of plant and animal immunity: symbionts as developmental signals. Trends Microbiol 2014; 22:607-13. [PMID: 25124464 DOI: 10.1016/j.tim.2014.07.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 07/09/2014] [Accepted: 07/16/2014] [Indexed: 02/07/2023]
Abstract
The functional similarity between root and gut microbiota, both contributing to the nutrition and protection of the host, is often overlooked. A central mechanism for efficient protection against pathogens is defense priming, the preconditioning of immunity induced by microbial colonization after germination or birth. Microbiota have been recruited several times in evolution as developmental signals for immunity maturation. Because there is no evidence that microbial signals are more relevant than endogenous ones, we propose a neutral scenario for the evolution of this dependency: any hypothetic endogenous signal can be lost because microbial colonization, reliably occurring at germination or birth, can substitute for it, and without either positive selection or the acquisition of new functions. Dependency of development on symbiotic signals can thus evolve by contingent irreversibility.
Collapse
Affiliation(s)
- Marc-André Selosse
- Muséum National d'Histoire Naturelle, Département Systématique et Evolution, Institut de Systématique, Evolution, Biodiversité (ISYEB, UMR 7205), CP 50, 45 rue Buffon, 75005 Paris, France.
| | - Alain Bessis
- Institut de Biologie de l'Ecole Normale Supérieure, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1024, Centre National de la Recherche Scientifique (CNRS) UMR 8197, 75005 Paris, France
| | - María J Pozo
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidin, Consejo Superior de Investigaciones Científicas (CSIC), Profesor Albareda 1, 18008 Granada, Spain
| |
Collapse
|
18
|
Van Etten ML, Deen AC, Hamrick JL, Chang SM. Mating system contributes only slightly to female maintenance in gynodioecious Geranium maculatum (Geraniaceae). Heredity (Edinb) 2014; 113:464-70. [PMID: 24824284 DOI: 10.1038/hdy.2014.48] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 03/23/2014] [Accepted: 03/27/2014] [Indexed: 11/09/2022] Open
Abstract
Gynodioecy, the co-occurrence of female and hermaphroditic individuals within a population, is an important intermediate in the evolution of separate sexes. The first step, female maintenance, requires females to have higher seed fitness compared with hermaphrodites. A common mechanism thought to increase relative female fitness is inbreeding depression avoidance, the magnitude of which depends on hermaphroditic selfing rates and the strength of inbreeding depression. Less well studied is the effect of biparental inbreeding on female fitness. Biparental inbreeding can affect relative female fitness only if its consequence or frequency differs between sexes, which could occur if sex structure and genetic structure both occur within populations. To determine whether inbreeding avoidance and/or biparental inbreeding can account for female persistence in Geranium maculatum, we measured selfing and biparental inbreeding rates in four populations and the spatial genetic structure in six populations. Selfing rates of hermaphrodites were low and did not differ significantly from zero in any population, leading to females gaining at most a 1-14% increase in seed fitness from inbreeding avoidance. Additionally, although significant spatial genetic structure was found in all populations, biparental inbreeding rates were low and only differed between sexes in one population, thereby having little influence on female fitness. A review of the literature revealed few sexual differences in biparental inbreeding among other gynodioecious species. Our results show that mating system differences may not fully account for female maintenance in this species, suggesting other mechanisms may be involved.
Collapse
Affiliation(s)
- M L Van Etten
- 1] Department of Plant Biology, University of Georgia, Athens, GA, USA [2] Department of Ecology, Institute of Agriculture and Environment, Massey University, Palmerston North, New Zealand
| | - A C Deen
- Department of Plant Biology, University of Georgia, Athens, GA, USA
| | - J L Hamrick
- Department of Plant Biology, University of Georgia, Athens, GA, USA
| | - S-M Chang
- Department of Plant Biology, University of Georgia, Athens, GA, USA
| |
Collapse
|
19
|
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.
Collapse
Affiliation(s)
- S Varga
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | | |
Collapse
|