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Oberhofer G, Johnson ML, Ivy T, Antoshechkin I, Hay BA. Cleave and Rescue gamete killers create conditions for gene drive in plants. NATURE PLANTS 2024; 10:936-953. [PMID: 38886522 DOI: 10.1038/s41477-024-01701-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 04/16/2024] [Indexed: 06/20/2024]
Abstract
Gene drive elements promote the spread of linked traits and can be used to change the composition or fate of wild populations. Cleave and Rescue (ClvR) drive elements sit at a fixed chromosomal position and include a DNA sequence-modifying enzyme such as Cas9/gRNAs that disrupts endogenous versions of an essential gene and a recoded version of the essential gene resistant to cleavage. ClvR spreads by creating conditions in which those lacking ClvR die because they lack functional versions of the essential gene. Here we demonstrate the essential features of the ClvR gene drive in the plant Arabidopsis thaliana through killing of gametes that fail to inherit a ClvR that targets the essential gene YKT61. Resistant alleles, which can slow or prevent drive, were not observed. Modelling shows plant ClvRs are robust to certain failure modes and can be used to rapidly drive population modification or suppression. Possible applications are discussed.
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Affiliation(s)
- Georg Oberhofer
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Michelle L Johnson
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Tobin Ivy
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Igor Antoshechkin
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Bruce A Hay
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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Matallana-Puerto CA, Duarte MO, Aguilar Fachin D, Poloni Guilherme C, Oliveira PE, Cardoso JCF. First evidence of late-acting self-incompatibility in the Aristolochiaceae. PLANT BIOLOGY (STUTTGART, GERMANY) 2024; 26:612-620. [PMID: 38634401 DOI: 10.1111/plb.13649] [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: 08/29/2023] [Accepted: 03/25/2024] [Indexed: 04/19/2024]
Abstract
Most Aristolochiaceae species studied so far are from temperate regions, bearing self-compatible protogynous trap flowers. Although self-incompatibility has been suggested for tropical species, the causes of self-sterility in this family remain unknown. To fill this gap, we studied the pollination of the tropical Aristolochia esperanzae, including the physical and physiological anti-selfing mechanisms. Floral visitors trapped inside flowers were collected to determine the pollinators. Protogyny was characterized by observing the temporal expression of sexual phases and stigmatic receptivity tests. The breeding system was investigated using hand-pollination treatments. Pollen tube growth was observed using epifluorescence to identify the self-incompatibility mechanism. Flies were the most frequent visitors found inside A. esperanzae trap flowers, with individuals from the family Ulidiidae being potential pollinators since they carried pollen. The characteristic flower odour and presence of larvae indicate that A. esperanzae deceives flies through oviposition-site mimicry. Although this species showed incomplete protogyny, stigmatic receptivity decreased during the male phase, avoiding self-pollination. Fruits developed only after cross- and open pollination, indicating that the population is non-autonomous, non-apomictic, and self-sterile. This occurred through a delay in the growth of geitonogamous pollen tubes to the ovary and lower ovule penetration, indicating a late-acting self-incompatibility mechanism. Our findings expand the number of families in which late-acting self-incompatibility has been reported, demonstrating that it is more widespread than previously thought, especially when considering less-studied tropical species among the basal angiosperms.
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Affiliation(s)
- C A Matallana-Puerto
- Programa de Pós-Graduação em Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - M O Duarte
- Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - D Aguilar Fachin
- Departamento de Ecologia, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Campus Samambaia, Goiânia, Goiás, Brazil
| | - C Poloni Guilherme
- Laboratório de Evolução e Morfologia de Diptera, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - P E Oliveira
- Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - J C F Cardoso
- Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, Minas Gerais, Brazil
- Departamento de Biodiversidade, Evolução e Meio Ambiente, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
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Wróblewska A, Ostrowiecka B, Brzosko E, Jermakowicz E, Tałałaj I, Mirski P. The patterns of inbreeding depression in food-deceptive Dactylorhiza orchids. FRONTIERS IN PLANT SCIENCE 2024; 15:1244393. [PMID: 38590747 PMCID: PMC10999633 DOI: 10.3389/fpls.2024.1244393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 03/04/2024] [Indexed: 04/10/2024]
Abstract
Introduction Inbreeding depression (ID) in food-deceptive plants have been reported previously, however, it has not been often proven that selfed seeds germinate better than outbred ones or that selfing affects ID. To resolved these issues, food-deceptive related Dactylorhiza majalis, D. incarnata var. incarnata and D. fuchsii orchids were investigated. Methods Hand pollination treatments and control pollination were conducted. Fruit set, number of seeds per fruit, seed length, number of well-developed seeds per fruit, and proportion of in vitro asymbiotic germination seeds, were analyzed in relation to inflorescence levels and used as fitness indicators for these orchids. The ID and pollen limitation were measured. Results The lowest ID (δ = -1.000) was in D. majalis, and present in combination with a high pollen limitation in its populations. D. fuchsii showed higher ID (δ = 0.366), and D. incarnata var. incarnata weak ID (δ = 0.065), although ID varied between its fitness components. The seed number per fruit differed significantly between the treatments and the inflorescence levels in treatments. Discussion This study emphasizes that the breeding system rather than the flower position on the inflorescence shaped the quality and quantity of reproductive output. The ID and its effect on germination of food-deceptive orchid seeds undoubtedly played an important role.
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Affiliation(s)
- Ada Wróblewska
- Faculty of Biology, University of Bialystok, Białystok, Poland
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Reutemann AV, Honfi AI, Karunarathne P, Eckers F, Hojsgaard DH, Martínez EJ. Comparative analysis of molecular and morphological diversity in two diploid Paspalum species (Poaceae) with contrasting mating systems. PLANT REPRODUCTION 2024; 37:15-32. [PMID: 37566236 DOI: 10.1007/s00497-023-00478-3] [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: 03/15/2023] [Accepted: 07/22/2023] [Indexed: 08/12/2023]
Abstract
KEY MESSAGE Interspecific comparison of two Paspalum species has demonstrated that mating systems (selfing and outcrossing) contribute to variation (genetically and morphologically) within species through similar but mutually exclusive processes. Mating systems play a key role in the genetic dynamics of populations. Studies show that populations of selfing plants have less genetic diversity than outcrossing plants. Yet, many such studies have ignored morphological diversity. Here, we compared the morphological and molecular diversity patterns in populations of two phylogenetically-related sexual diploids that differ in their mating system: self-sterile Paspalum indecorum and self-fertile P. pumilum. We assessed the morphological variation using 16 morpho-phenological characters and the molecular diversity using three combinations of AFLPs. We compared the morphological and molecular diversity within and among populations in each mating system. Contrary to expectations, selfers showed higher morphological variation within populations, mainly in vegetative and phenological traits, compared to outcrossers. The high morphological variation within populations of selfers led to a low differentiation among populations. At molecular level, selfing populations showed lower levels of genotypic and genetic diversity than outcrossing populations. As expected, selfers showed higher population structure than outcrossers (PhiST = 0.301 and PhiST = 0.108, respectively). Increased homozygous combinations for the same trait/locus enhance morphological variation and reduce molecular variation within populations in selfing P. pumilum. Thus, selfing outcomes are opposite when comparing morphological and molecular variation in P. pumilum. Meanwhile, pollen flow in obligate outcrossing populations of P. indecorum increases within-population molecular variation, but tends to homogenize phenotypes within-population. Pollen flow in obligate outcrossers tends to merge geographically closer populations; but isolation by distance can lead to a weak differentiation among distant populations of P. indecorum.
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Affiliation(s)
- A Verena Reutemann
- Instituto de Botánica del Nordeste (IBONE-CONICET-UNNE), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), 3400, Corrientes, Argentina
| | - Ana I Honfi
- Programa de Estudios Florísticos y Genética Vegetal, Instituto de Biología Subtropical (PEFyGV, IBS-UNaM-CONICET), 3300, Posadas, Argentina
| | - Piyal Karunarathne
- Department of Systematics, Biodiversity and Evolution of Plants, Albrecht-Von-Haller Institute for Plant Sciences, University of Goettingen, 37073, Goettingen, Germany
- Institute for Population Genetics, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Fabiana Eckers
- Programa de Estudios Florísticos y Genética Vegetal, Instituto de Biología Subtropical (PEFyGV, IBS-UNaM-CONICET), 3300, Posadas, Argentina
| | - Diego H Hojsgaard
- Taxonomy and Evolutionary Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
| | - Eric J Martínez
- Instituto de Botánica del Nordeste (IBONE-CONICET-UNNE), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), 3400, Corrientes, Argentina.
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Moracho E, Klein EK, Oddou-Muratorio S, Hampe A, Jordano P. Highly clustered mating networks in naturally fragmented riparian tree populations. Mol Ecol 2024; 33:e17285. [PMID: 38288563 DOI: 10.1111/mec.17285] [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: 06/26/2023] [Revised: 12/11/2023] [Accepted: 12/13/2023] [Indexed: 03/07/2024]
Abstract
Understanding how spatial patterns of mating and gene flow respond to habitat loss and geographical isolation is a crucial aspect of forest fragmentation genetics. Naturally fragmented riparian tree populations exhibit unique characteristics that significantly influence these patterns. In this study, we investigate mating patterns, pollen-mediated gene flow, and genetic diversity in relict populations of Frangula alnus in southern Spain by testing specific hypotheses related to the riparian habitat. We employ a novel approach that combines paternity analysis, particularly suited for small and isolated populations, with complex network theory and Bayesian models to predict mating likelihood among tree pairs. Our findings reveal a prevalence of short-distance pollination, resulting in spatially driven local mating clusters with a distinct subset of trees being highly connected in the mating network. Additionally, we observe numerous pollination events over distances of hundreds of metres and considerable pollen immigration. Local neighbourhood density is the primary factor influencing within-population mating patterns and pollen dispersal; moreover, mating network properties reflect the population's size and spatial configuration. Conversely, among-population pollen dispersal is mainly determined by tree size, which influences floral display. Our results do not support a major role of directional pollen dispersal in longitudinal trends of genetic diversity. We provide evidence that long-term fragmented tree populations persist in unique environments that shape mating patterns and impose constraints to pollen-mediated gene flow. Nevertheless, even seemingly strongly isolated populations can maintain functional connectivity over extended periods, especially when animal-mediated mating networks promote genetic diversity, as in this riparian tree species.
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Affiliation(s)
- Eva Moracho
- Integrative Ecology Group, Estación Biológica de Doñana (EBD-CSIC), Sevilla, Spain
| | - Etienne K Klein
- Ecologie des Forêts Méditerranéennes, UR 629, INRA, Avignon, France
- Biostatistique et Processus Spatiaux, UR 546, INRA, Avignon, France
| | | | - Arndt Hampe
- INRA, UMR1202 BIOGECO, Cestas, France
- Univ. Bordeaux, UMR1202 BIOGECO, Talence, France
| | - Pedro Jordano
- Integrative Ecology Group, Estación Biológica de Doñana (EBD-CSIC), Sevilla, Spain
- Dept. Biología Vegetal y Ecología, Universidad de Sevilla, Sevilla, Spain
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Strelin MM, da Cunha NL, Rubini-Pisano A, Fornoni J, Aizen MA. Darwin's inflorescence syndrome is indeed associated with bee pollination. PLANT REPRODUCTION 2024; 37:37-45. [PMID: 37646855 DOI: 10.1007/s00497-023-00480-9] [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: 05/08/2023] [Accepted: 08/06/2023] [Indexed: 09/01/2023]
Abstract
KEY MESSAGE A relationship between vertical acropetal inflorescences with protandrous flowers and bee pollination was hypothesized by Darwin back in 1877. Here we provide empirical evidence supporting this association across the angiosperms. Plant reproduction is not only determined by flower traits but also by the arrangement of flowers within inflorescences. Based on his observations of the orchid Spiranthes autumnalis, Darwin proposed in 1877 that bee-pollinated plants presenting protandrous flowers on vertical acropetal inflorescences, where proximal flowers open first, can exploit the stereotypical foraging behavior of their pollinators (i.e., upward movement through the inflorescence) to promote pollen exportation and reduce self-pollination. In these inflorescences, male-phase flowers lie spatially above female-phase flowers. To examine this untested hypothesis, we compiled literature information from 718 angiosperms species and evaluated the association between vertical acropetal inflorescences with protandrous flowers and bee pollination within a phylogenetic comparative framework. Results reveal that this type of inflorescence is indeed more common in species pollinated by bees. Moreover, this association does not seem to be weakened by the presence of alternative self-pollination avoidance mechanisms, like self-incompatibility, suggesting that this inflorescence type benefits mainly male rather than female fitness. Other inflorescence types placing male-phase flowers above female-phase flowers, e.g., vertical basipetal inflorescences with protogynous flowers, do not provide strong evidence of a differential association with pollination by bees. Female-biased nectar production in vertical acropetal inflorescences with protandrous flowers may reinforce the behavior of bees to fly upwards, rendering Darwin's configuration more adaptive than other inflorescence configurations.
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Affiliation(s)
- Marina M Strelin
- Grupo de Investigación en Ecología de La Polinización, Laboratorio Ecotono, INIBIOMA (CONICET-Universidad Nacional del Comahue), San Carlos de Bariloche, Río Negro, Argentina.
| | - Nicolay L da Cunha
- Grupo de Investigación en Ecología de La Polinización, Laboratorio Ecotono, INIBIOMA (CONICET-Universidad Nacional del Comahue), San Carlos de Bariloche, Río Negro, Argentina
| | - Aimé Rubini-Pisano
- Instituto de Ecología, Universidad Nacional Autónoma de México, Apartado Postal 70-275, 04510, Ciudad de Mexico, Mexico
| | - Juan Fornoni
- Instituto de Ecología, Universidad Nacional Autónoma de México, Apartado Postal 70-275, 04510, Ciudad de Mexico, Mexico
| | - Marcelo A Aizen
- Grupo de Investigación en Ecología de La Polinización, Laboratorio Ecotono, INIBIOMA (CONICET-Universidad Nacional del Comahue), San Carlos de Bariloche, Río Negro, Argentina
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Shelton WR, Mitchell RJ, Christopher DA, Jack LP, Karron JD. Among-individual variation in flowering phenology affects flowering synchrony and mating opportunity. AMERICAN JOURNAL OF BOTANY 2024; 111:e16269. [PMID: 38126922 DOI: 10.1002/ajb2.16269] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 12/23/2023]
Abstract
PREMISE The timing and pattern of a plant's flowering can have important consequences for reproductive success. Variation in flowering phenology may influence the number of prospective mates, the risk of mating with lower quality individuals, and the likelihood of self-pollination. Here we use a common garden experiment to explore within- and among-population variation in phenology. Our work provides new insights into how flowering phenology shapes mating opportunity and flowering synchrony in a self-compatible perennial. METHODS To quantify variation in flowering phenology we raised progeny from nine populations of Mimulus ringens in a common garden. For each individual, we measured phenological traits including age at flowering onset, daily floral display size, total flower number, and flowering synchrony with other members of the population, and related these traits to mating opportunity. We also tested how individual flowering schedules influence the magnitude of synchrony. RESULTS Flowering phenology and synchrony varied substantially within and among populations. From day to day, plants often oscillated between large and small daily floral displays. Additionally, flowering schedules of individual plants strongly influenced flowering synchrony and, along with the number of flowering days, markedly affected plants' mating opportunity. CONCLUSIONS Phenological traits such as flowering synchrony can affect the quantity of mating opportunities and may be important targets of natural selection. Our results highlight the need for studies that quantify flowering patterns of individuals as well as populations.
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Affiliation(s)
- Wendy R Shelton
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
| | | | - Dorothy A Christopher
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
- Department of Biology, Western Connecticut State University, Danbury, Connecticut, 06810, USA
| | - Loretha P Jack
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
| | - Jeffrey D Karron
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin, 53201, USA
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Johnson SD, Harder LD. The economy of pollen dispersal in flowering plants. Proc Biol Sci 2023; 290:20231148. [PMID: 37788703 PMCID: PMC10547555 DOI: 10.1098/rspb.2023.1148] [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: 05/23/2023] [Accepted: 09/06/2023] [Indexed: 10/05/2023] Open
Abstract
Mating success of flowering plants depends strongly on the efficiencies of pollen removal from flowers and its subsequent dispersal to conspecific stigmas. We characterized the economy of pollen dispersal in flowering plants by analysing pollen fates and their correlates for 228 species. The mean percentage of pollen removed from flowers (removal efficiency) varied almost twofold according to the type of pollen-dispersal unit, from less than 45% for orchids and milkweeds with solid pollinia, to greater than 80% for species with granular monads or sectile (segmented) pollinia. The mean percentage of removed pollen reaching stigmas (pollen transfer efficiency, PTE) varied from 2.4% for species with separate monads to 27.0% for orchids with solid pollinia. These values tended to be higher in plants with single pollinator species and in those with non-grooming pollinators. Nectar production increased removal efficiency, but did not influence PTE. Among types of pollen-dispersal units, the net percentage of produced pollen that was dispersed to stigmas varied negatively with removal efficiency and positively with PTE, indicating the relative importance of the latter for overall pollen economy. These findings confirm the key importance of floral traits, particularly pollen packaging, for pollen dispersal outcomes and highlight the under-appreciated pollination efficiency of non-grooming pollinators.
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Affiliation(s)
- Steven D. Johnson
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa
| | - Lawrence D. Harder
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada T2N 1N4
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Bisang I, Ehrlén J, Hedenäs L. Life-history characteristics and historical factors are important to explain regional variation in reproductive traits and genetic diversity in perennial mosses. ANNALS OF BOTANY 2023; 132:29-42. [PMID: 36928083 PMCID: PMC10550275 DOI: 10.1093/aob/mcad045] [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: 03/03/2023] [Accepted: 03/15/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND AND AIMS Plants have evolved an unrivalled diversity of reproductive strategies, including variation in the degree of sexual vs. clonal reproduction. This variation has important effects on the dynamics and genetic structure of populations. We examined the association between large-scale variation in reproductive patterns and intraspecific genetic diversity in two moss species where sex is manifested in the dominant haploid generation and sex expression is irregular. We predicted that in regions with more frequent realized sexual reproduction, populations should display less skewed sex ratios, should more often express sex and should have higher genetic diversity than in regions with largely clonal reproduction. METHODS We assessed reproductive status and phenotypic sex in the dioicous long-lived Drepanocladus trifarius and D. turgescens, in 248 and 438 samples across two regions in Scandinavia with frequent or rare realized sexual reproduction, respectively. In subsets of the samples, we analysed genetic diversity using nuclear and plastid sequence information and identified sex with a sex-specific molecular marker in non-reproductive samples. KEY RESULTS Contrary to our predictions, sex ratios did not differ between regions; genetic diversity did not differ in D. trifarius and it was higher in the region with rare sexual reproduction in D. turgescens. Supporting our predictions, relatively more samples expressed sex in D. trifarius in the region with frequent sexual reproduction. Overall, samples were mostly female. The degree of sex expression and genetic diversity differed between sexes. CONCLUSIONS Sex expression levels, regional sex ratios and genetic diversity were not directly associated with the regional frequency of realized sexual reproduction, and relationships and variation patterns differed between species. We conclude that a combination of species-specific life histories, such as longevity, overall degree of successful sexual reproduction and recruitment, and historical factors are important to explain this variation. Our data on haploid-dominated plants significantly complement plant reproductive biology.
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Affiliation(s)
- Irene Bisang
- Department of Botany, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden
| | - Johan Ehrlén
- Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Lars Hedenäs
- Department of Botany, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden
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Surina B, Balant M, Glasnović P, Radosavljević I, Fišer Ž, Fujs N, Castro S. Population size as a major determinant of mating system and population genetic differentiation in a narrow endemic chasmophyte. BMC PLANT BIOLOGY 2023; 23:383. [PMID: 37553615 PMCID: PMC10411015 DOI: 10.1186/s12870-023-04384-8] [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: 02/06/2023] [Accepted: 07/18/2023] [Indexed: 08/10/2023]
Abstract
BACKGROUND Mating system is one of the major determinants of intra- and interspecific genetic structure, but may vary within and between plant populations. Our study model included all known populations of Moehringia tommasinii (Caryophyllaceae), a narrow endemic plant inhabiting rock crevices in the northwestern Adriatic, and some populations of co-occurring and widespread M. muscosa, an ecologically divergent relative with an overlapping flowering period. We performed reciprocal crosses within and between taxa and used molecular markers to assess the extent of gene flow within and between populations and taxa. Using coefficient of inbreeding, population size, seed weight, pollen-to-ovule ratio, and flower display size, we also looked for evidence of a selfing syndrome. RESULTS A surprisingly high variation in mating systems was observed among populations of M. tommasinii. These populations exhibited genetic structuring, with their size positively correlated with both seed weight and pollen production. Although a selfing syndrome could not be confirmed as the majority of selfing resulted from allogamous treatments, the occurrence of selfing was notable. In the presence of M. muscosa, at a site where both species coexist closely, a distinct pattern of fruit production was observed in M. tommasinii following various pollination treatments. Molecular and morphometric data provided evidence of hybridization followed by local extinction at this site. CONCLUSIONS Population size proved to be the most important factor affecting the mating system in genetically structured populations of M. tommasinii. Lighter seeds and lower pollen production observed in populations with pronounced selfing do not provide enough evidence for the selfing syndrome. Detected gene flow between M. tommasinii and the sympatric M. muscosa suggested weak reproductive barriers between the taxa, which could pose a conservation problems for the former species. Hybridization leading to local extinction may also resulted in floral polymorphism and disruption of mating patterns of M. tommasinii.
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Affiliation(s)
- Boštjan Surina
- Natural History Museum Rijeka, Lorenzov prolaz 1, 51000, Rijeka, Croatia.
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Glagoljaška 8, 6000, Koper, Slovenia.
| | - Manica Balant
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Glagoljaška 8, 6000, Koper, Slovenia
- Institut Botànic de Barcelona (IBB, CSIC-Ajuntament de Barcelona), Passeig del Migdia s.n., Parc de Montjuïc, 08038, Barcelona, Spain
| | - Peter Glasnović
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Glagoljaška 8, 6000, Koper, Slovenia
| | - Ivan Radosavljević
- Division of Botany, Department of Biology, Faculty of Science, University of Zagreb, Marulićev trg 9a, 10000, Zagreb, Croatia
- Centre of Excellence for Biodiversity and Molecular Plant Breeding, Svetošimunska cesta 25, 10000, Zagreb, Croatia
| | - Živa Fišer
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Glagoljaška 8, 6000, Koper, Slovenia
| | - Nataša Fujs
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Glagoljaška 8, 6000, Koper, Slovenia
| | - Sílvia Castro
- Centre for Functional Ecology-Science for People & the Planet, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
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Zhang W, Hu Y, Zhang S, Shao J. Integrative taxonomy in a rapid speciation group associated with mating system transition: A case study in the Primula cicutariifolia complex. Mol Phylogenet Evol 2023:107840. [PMID: 37279815 DOI: 10.1016/j.ympev.2023.107840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/30/2023] [Accepted: 06/02/2023] [Indexed: 06/08/2023]
Abstract
Accurate species delimitation is the key to biodiversity conservation and is fundamental to most branches of biology. However, species delimitation remains challenging in those evolutionary radiations associated with mating system transition from outcrossing to self-fertilization, which have frequently occurred in angiosperms and are usually accompanied by rapid speciation. Here, using the Primula cicutariifolia complex as a case, we integrated molecular, morphological and reproductive isolation evidence to test and verify whether its outcrossing (distylous) and selfing (homostylous) populations have developed into independent evolutionary lineages. Phylogenetic trees based on whole plastomes and SNPs of the nuclear genome both indicated that the distylous and homostylous populations grouped into two different clades. Multispecies coalescent, gene flow and genetic structure analyses all supported such two clades as two different genetic entities. In morphology, as expected changes in selfing syndrome, homostylous populations have significantly fewer umbel layers and smaller flower and leaf sizes compared to distylous populations, and the variation range of some floral traits, such as corolla diameter and umbel layers, show obvious discontinuity. Furthermore, hand-pollinated hybridization between the two clades produced almost no seeds, indicating that well post-pollination reproductive isolation has been established between them. Therefore, the distylous and homostylous populations in this studied complex are two independent evolutionary lineages, and thus these distylous populations should be treated as a distinct species, here named Primula qiandaoensis W. Zhang & J.W. Shao sp. nov.. Our empirical study of the P. cicutariifolia complex highlights the importance of applying multiple lines of evidence, in particular genomic data, to delimit species in pervasive evolutionary plant radiations associated with mating system transition.
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Affiliation(s)
- Wei Zhang
- College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China; College of Life Sciences, Anqing Normal University, Anqing 246011, Anhui, China
| | - Yingfeng Hu
- College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
| | - Siyu Zhang
- College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
| | - Jianwen Shao
- College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China; Provincial Key Laboratory of Conservation and Utilization of Biological Resources, Wuhu 241000, Anhui, China.
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12
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da Cunha NL, Aizen MA. Pollen production per flower increases with floral display size across animal-pollinated flowering plants. AMERICAN JOURNAL OF BOTANY 2023:e16180. [PMID: 37243835 DOI: 10.1002/ajb2.16180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 02/08/2023] [Accepted: 02/09/2023] [Indexed: 05/29/2023]
Abstract
PREMISE The number of open flowers on a plant (i.e., floral display size) can influence plant fitness by increasing pollinator attraction. However, diminishing marginal fitness returns with increasing floral display are expected as pollinators tend to visit more flowers per plant consecutively. An extended flower visitation sequence increases the fraction of ovules disabled by self-pollination (ovule discounting) and reduces the fraction of a plant's own pollen that is exported to sire seeds in other plants (pollen discounting). Hermaphroditic species with a genetic system that prevents self-fertilization (self-incompatibility) would avoid ovule discounting and its fitness cost, whereas species without such a genetically based barrier would not. Contrarily, pollen discounting would be an unavoidable consequence of a large floral display irrespective of selfing barriers. Nevertheless, the increasing fitness costs of ovule and pollen discounting could be offset by respectively increasing ovule and pollen production per flower. METHODS We compiled data on floral display size and pollen and ovule production per flower for 1241 animal-pollinated, hermaphroditic angiosperm species, including data on the compatibility system for 779 species. We used phylogenetic general linear mixed models to assess the relations of pollen and ovule production to floral display size. RESULTS Our findings provide evidence of increasing pollen production, but not of ovule production, with increasing display size irrespective of compatibility system and even after accounting for potentially confounding effects like flower size and growth form. CONCLUSIONS Our comparative study supports the pollen-discount expectation of an adaptive link between per-flower pollen production and floral display across animal-pollinated angiosperms.
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Affiliation(s)
- Nicolay Leme da Cunha
- Grupo de Ecología de la Polinización, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), Universidad Nacional del Comahue-CONICET, 8400, San Carlos de Bariloche, Argentina
| | - Marcelo Adrián Aizen
- Grupo de Ecología de la Polinización, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), Universidad Nacional del Comahue-CONICET, 8400, San Carlos de Bariloche, Argentina
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13
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Schedler M, Reutemann AV, Hojsgaard DH, Zilli AL, Brugnoli EA, Galdeano F, Acuña CA, Honfi AI, Martínez EJ. Alternative Evolutionary Pathways in Paspalum Involving Allotetraploidy, Sexuality, and Varied Mating Systems. Genes (Basel) 2023; 14:1137. [PMID: 37372317 DOI: 10.3390/genes14061137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 05/17/2023] [Accepted: 05/22/2023] [Indexed: 06/29/2023] Open
Abstract
The genetic systems of Paspalum species have not been extensively studied. We analyzed the ploidy, reproductive mode, mating system, and fertility of four Paspalum species-Paspalum durifolium, Paspalum ionanthum, Paspalum regnellii, and Paspalum urvillei. An analysis of 378 individuals from 20 populations of northeastern Argentina was conducted. All populations of the four Paspalum species were pure tetraploid and had a sexual and stable reproductive mode. However, some populations of P. durifolium and P. ionanthum showed low levels of apospory. Populations of P. durifolium and P. ionanthum had low seed sets under self-pollination but were fertile under open pollination, showing that self-incompatibility likely caused self-sterility. In contrast, populations of P. regnellii or P. urvillei showed no evidence of apospory, and seed sets in both self- and open pollination conditions were high, suggesting that they are self-compatible due to the absence of pollen-pistil molecular incompatibility mechanisms. The evolutionary origin of the four Paspalum species could explain these differences. This study supplies valuable insights into the genetic systems of Paspalum species, which could have implications for their conservation and management.
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Affiliation(s)
- Mara Schedler
- Instituto de Botánica del Nordeste (IBONE-UNNE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes 3400, Corrientes, Argentina
| | - Anna Verena Reutemann
- Instituto de Botánica del Nordeste (IBONE-UNNE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes 3400, Corrientes, Argentina
| | - Diego Hernán Hojsgaard
- Taxonomy & Evolutionary Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466 Gatersleben, Germany
| | - Alex Leonel Zilli
- Instituto de Botánica del Nordeste (IBONE-UNNE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes 3400, Corrientes, Argentina
| | - Elsa Andrea Brugnoli
- Instituto de Botánica del Nordeste (IBONE-UNNE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes 3400, Corrientes, Argentina
| | - Florencia Galdeano
- Instituto de Botánica del Nordeste (IBONE-UNNE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes 3400, Corrientes, Argentina
| | - Carlos Alberto Acuña
- Instituto de Botánica del Nordeste (IBONE-UNNE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes 3400, Corrientes, Argentina
| | - Ana Isabel Honfi
- Programa de Estudios Florísticos y Genética Vegetal, Instituto de Biología Subtropical (PEFyGV, IBS-UNaM-CONICET), Posadas 3300, Misiones, Argentina
| | - Eric Javier Martínez
- Instituto de Botánica del Nordeste (IBONE-UNNE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes 3400, Corrientes, Argentina
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14
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Torres-Vanegas F, Hadley AS, Kormann UG, Jones FA, Betts MG, Wagner HH. Pollinator foraging tactics have divergent consequences for the mating system of a tropical plant. THE NEW PHYTOLOGIST 2023; 237:1050-1066. [PMID: 36285370 DOI: 10.1111/nph.18574] [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: 12/10/2021] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Resolving the consequences of pollinator foraging behaviour for plant mating systems is a fundamental challenge in evolutionary ecology. Pollinators may adopt particular foraging tactics: complete trapline foraging (repeated movements along a fixed route), sample-and-shift trapline foraging (a variable route that incorporates information from previous experiences) and territorial foraging (stochastic movements within a restricted area). Studies that integrate these pollinator foraging tactics with plant mating systems are generally lacking. We investigate the consequences of particular pollinator foraging tactics for Heliconia tortuosa. We combine parentage and sibship inference analysis with simulation modelling to: estimate mating system parameters; infer the foraging tactic adopted by the pollinators; and quantify the impact of pollinator foraging tactics on mating system parameters. We found high outcrossing rates, ubiquitous multiple paternity and a pronounced departure from near-neighbour mating. We also found that plants repeatedly receive pollen from a series of particular donors. We infer that the pollinators primarily adopt complete trapline foraging and occasionally engage in sample-and-shift trapline foraging. This enhances multiple paternity without a substantial increase in near-neighbour mating. The particular pollinator foraging tactics have divergent consequences for multiple paternity and near-neighbour mating. Thus, pollinator foraging behaviour is an important driver of the ecology and evolution of plant mating systems.
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Affiliation(s)
- Felipe Torres-Vanegas
- Department of Ecology and Evolutionary Biology, University of Toronto, Mississauga, ON, L5L 1C6, Canada
| | - Adam S Hadley
- Department of Ecology and Evolutionary Biology, University of Toronto, Mississauga, ON, L5L 1C6, Canada
- Forest Biodiversity Research Network, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331-5704, USA
- Biodiversity Section, Department of Natural Resources and Energy Development, Fredericton, NB, E3C 2G6, Canada
| | - Urs G Kormann
- Swiss Ornithological Institute, Sempach, CH-6204, Switzerland
| | - Frank Andrew Jones
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, 97331, USA
- Smithsonian Tropical Research Institute, Panama City, 0843-03092, Panama
| | - Matthew G Betts
- Forest Biodiversity Research Network, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331-5704, USA
| | - Helene H Wagner
- Department of Ecology and Evolutionary Biology, University of Toronto, Mississauga, ON, L5L 1C6, Canada
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15
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Reproductive biology and population structure of the endangered shrub Grevillea bedggoodiana (Proteaceae). CONSERV GENET 2022. [DOI: 10.1007/s10592-022-01480-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractNarrowly endemic species are particularly vulnerable to catastrophic events. Compared to widespread species, they may also be less capable of adapting to shifts in environmental pressures as a result of specialisation on a narrow range of local condition and limited ability to disperse. However, life-history traits, such as preferential outcrossing and high fecundity can maintain genetic diversity and evolutionary potential, and boost species resilience. The endangered Grevillea bedggoodiana (Enfield Grevillea) is an understorey shrub restricted to an area of ca. 150 km2 in south-eastern Australia with a legacy of large-scale anthropogenic disturbance. Prior to this study little was known about its biology and population structure. Here, its breeding system was assessed through a controlled pollination experiment at one of its central populations, and eight populations were sampled for genetic analysis with microsatellite markers. The species was found to be preferentially outcrossing, with no evidence of pollination limitation. In most populations, allelic richness, observed heterozygosity and gene diversity were high (Ar: 3.8–6.3; Ho: 0.45–0.65, He: 0.60 − 0.75). However, the inbreeding coefficients were significant in at least four populations, ranging from Fi -0.061 to 0.259 despite high outcrossing rates. Estimated reproductive rates varied among sampled populations but were independent of gene diversity and inbreeding. Despite its small geographic range, the species’ populations showed moderate differentiation (AMOVA: FST = 0.123), which was largely attributable to isolation by distance. We interpret these results as suggesting that G. bedggoodiana is reproductively healthy and has maintained high levels of genetic diversity despite recent disturbance.
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16
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Moles AT, Dalrymple RL, Raghu S, Bonser SP, Ollerton J. Advancing the missed mutualist hypothesis, the under-appreciated twin of the enemy release hypothesis. Biol Lett 2022; 18:20220220. [PMID: 36259169 PMCID: PMC9579764 DOI: 10.1098/rsbl.2022.0220] [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] [Indexed: 11/16/2022] Open
Abstract
Introduced species often benefit from escaping their enemies when they are transported to a new range, an idea commonly expressed as the enemy release hypothesis. However, species might shed mutualists as well as enemies when they colonize a new range. Loss of mutualists might reduce the success of introduced populations, or even cause failure to establish. We provide the first quantitative synthesis testing this natural but often overlooked parallel of the enemy release hypothesis, which is known as the missed mutualist hypothesis. Meta-analysis showed that plants interact with 1.9 times more mutualist species, and have 2.3 times more interactions with mutualists per unit time in their native range than in their introduced range. Species may mitigate the negative effects of missed mutualists. For instance, selection arising from missed mutualists could cause introduced species to evolve either to facilitate interactions with a new suite of species or to exist without mutualisms. Just as enemy release can allow introduced populations to redirect energy from defence to growth, potentially evolving increased competitive ability, species that shift to strategies without mutualists may be able to reallocate energy from mutualism toward increased competitive ability or seed production. The missed mutualist hypothesis advances understanding of the selective forces and filters that act on plant species in the early stages of introduction and establishment and thus could inform the management of introduced species.
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Affiliation(s)
- Angela T. Moles
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - Rhiannon L. Dalrymple
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - S. Raghu
- CSIRO, GPO Box 2583, Brisbane, Queensland 4001, Australia
| | - Stephen P. Bonser
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - Jeff Ollerton
- Faculty of Arts, Science and Technology, University of Northampton, Waterside Campus, Northampton NN1 5PH, UK,Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, People's Republic of China
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17
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Song B, Sun L, Barrett SCH, Moles AT, Luo YH, Armbruster WS, Gao YQ, Zhang S, Zhang ZQ, Sun H. Global analysis of floral longevity reveals latitudinal gradients and biotic and abiotic correlates. THE NEW PHYTOLOGIST 2022; 235:2054-2065. [PMID: 35611604 DOI: 10.1111/nph.18271] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
The length of time a flower remains open and functional - floral longevity - governs important reproductive processes influencing pollination and mating and varies considerably among angiosperm species. However, little is known about large-scale biogeographic patterns and the correlates of floral longevity. Using published data on floral longevity from 818 angiosperm species in 134 families and 472 locations world-wide, we present the first global quantification of the latitudinal pattern of floral longevity and the relationships between floral longevity and a range of biotic and abiotic factors. Floral longevity exhibited a significant phylogenetic signal and was longer at higher latitudes in both northern and southern hemispheres, even after accounting for elevation. This latitudinal variation was associated with several biotic and abiotic variables. The mean temperature of the flowering season had the highest predictive power for floral longevity, followed by pollen number per flower. Surprisingly, compatibility status, flower size, pollination mode, and growth form had no significant effects on flower longevity. Our results suggest that physiological processes associated with floral maintenance play a key role in explaining latitudinal variation in floral longevity across global ecosystems, with potential implications for floral longevity under global climate change and species distributions.
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Affiliation(s)
- Bo Song
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- Yunnan International Joint Laboratory for Biodiversity of Central Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Lu Sun
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Spencer C H Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON, M5S 3B2, Canada
| | - Angela T Moles
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Ya-Huang Luo
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - W Scott Armbruster
- School of Biological Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
| | - Yong-Qian Gao
- Yunnan Forestry Technological College, Kunming, 650224, China
| | - Shuang Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Zhi-Qiang Zhang
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming, 650504, China
| | - Hang Sun
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
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18
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Simón‐Porcar VI, Muñoz‐Pajares AJ, de Castro A, Arroyo J. Direct evidence supporting Darwin's hypothesis of cross-pollination promoted by sex organ reciprocity. THE NEW PHYTOLOGIST 2022; 235:2099-2110. [PMID: 35596603 PMCID: PMC9546006 DOI: 10.1111/nph.18266] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/09/2022] [Indexed: 05/28/2023]
Abstract
The floral phenotype plays a main role in the attraction and fit of pollinators. Both perianth traits and the positioning of sex organs can be subjected to natural selection and determine nonrandom mating patterns in populations. In stylar-polymorphic species, the Darwinian hypothesis predicts increased mating success between individuals with sex organs at equivalent heights (i.e. with higher reciprocity). We used paternity analyses in experimental populations of a stylar-dimorphic species. By comparing the observed mating patterns with those expected under random mating, we tested the effects of sex organ reciprocity and perianth traits on mating success. We also analysed phenotypic selection on perianth traits through female and male functions. The (dis)similarity of parental perianth traits had no direct effects on the mating patterns. Sex organ reciprocity had a positive effect on mating success. Narrow floral tubes increased this effect in upper sex organs. Perianth traits showed little signs of phenotypic selection. Female and absolute fitness measures resulted in different patterns of phenotypic selection. We provide precise empirical evidence of the Darwinian hypothesis about the functioning of stylar polymorphisms, demonstrating that mating patterns are determined by sex organ reciprocity and only those perianth traits which are critical to pollinator fit.
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Affiliation(s)
| | - A. Jesús Muñoz‐Pajares
- Department of GeneticsUniversity of GranadaE‐18071GranadaSpain
- Research Centre in Biodiversity and Genetic Resources (CIBIO)Campus Agrário de Vairão4485‐661VairãoPortugal
| | - Alejandra de Castro
- Department of Plant Biology and EcologyUniversity of SevilleE‐41080SevilleSpain
| | - Juan Arroyo
- Department of Plant Biology and EcologyUniversity of SevilleE‐41080SevilleSpain
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19
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Aljiboury AA, Friedman J. Mating and fitness consequences of variation in male allocation in a wind-pollinated plant. Evolution 2022; 76:1762-1775. [PMID: 35765717 DOI: 10.1111/evo.14544] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 04/26/2022] [Accepted: 05/04/2022] [Indexed: 01/22/2023]
Abstract
In hermaphrodites, the allocation of resources to each sex function can influence fitness through mating success. A prediction that arises from sex allocation theory is that in wind-pollinated plants, male fitness should increase linearly with investment of resources into male function but there have been few empirical tests of this prediction. In a field experiment, we experimentally manipulated allocation to male function in Ambrosia artemisiifolia (common ragweed) and measured mating success in contrasting phenotypes using genetic markers. We investigated the effects of morphological traits and flowering phenology on male siring success, and on the diversity of mates. Our results provide evidence for a linear relation between allocation to male function, mating, and fitness. We find earlier onset of male flowering time increases reproductive success, whereas later flowering increases the probability of mating with diverse individuals. Our study is among the first empirical tests of the prediction of linear male fitness returns in wind-pollinated plants and emphasizes the importance of a large investment into male function by wind-pollinated plants and mating consequences of temporal variation in sex allocation.
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Affiliation(s)
- Abrar A Aljiboury
- Department of Biology, Syracuse University, Syracuse, New York, 13244
| | - Jannice Friedman
- Department of Biology, Syracuse University, Syracuse, New York, 13244.,Department of Biology, Queen's University, Kingston, Canada, K7L 3N6
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20
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Rivkin LR, Johnson MTJ. The impact of urbanization on outcrossing rate and population genetic variation in the native wildflower, Impatiens capensis. JOURNAL OF URBAN ECOLOGY 2022. [DOI: 10.1093/jue/juac009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Cities are one of the fastest growing ecosystems on the planet, and conserving urban biodiversity is of primary importance. Urbanization increases habitat fragmentation and may be particularly problematic for native plant species which often exist in small, remnant populations in cities. We studied the effects of urbanization on Impatiens capensis, a self-compatible native wildflower, which is an important nectar and pollen source for native bees and hummingbirds. We sampled I. capensis from six populations located in urban and rural habitats in Toronto, Ontario, Canada. We sequenced the DNA of 43 families (N = 86 individuals) using genotype-by-sequencing to obtain 5627 single nucleotide polymorphisms. From each parent and offspring, we estimated individual outcrossing rates, population-level genetic diversity and genetic structure among populations. We found that 95% of plants were outcrossed, and populations were genetically differentiated, where urban populations contained a subset of the genetic variation found in rural populations. Urban populations exhibited lower genetic diversity than rural populations, and we detected a relationship between population census size and habitat on genetic diversity. Despite high outcrossing rates, our results suggest that urbanization reduces the genetic diversity of I. capensis populations, potentially increasing the vulnerability of these populations to long-term population declines and extirpation in response to urbanization.
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Affiliation(s)
- L Ruth Rivkin
- Department of Ecology and Evolutionary Biology, University of Toronto , Toronto, ON, M5S3B2 Canada
- Department of Biology, University of Toronto Mississauga , Toronto, ON, L5L1C6 Canada
- Centre for Urban Environments, University of Toronto Mississauga , Toronto, ON, L5L1C6 Canada
| | - Marc T J Johnson
- Department of Biology, University of Toronto Mississauga , Toronto, ON, L5L1C6 Canada
- Centre for Urban Environments, University of Toronto Mississauga , Toronto, ON, L5L1C6 Canada
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21
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Cisternas‐Fuentes A, Jogesh T, Broadhead GT, Raguso RA, Skogen KA, Fant JB. Evolution of selfing syndrome and its influence on genetic diversity and inbreeding: A range-wide study in Oenothera primiveris. AMERICAN JOURNAL OF BOTANY 2022; 109:789-805. [PMID: 35596689 PMCID: PMC9320852 DOI: 10.1002/ajb2.1861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/09/2022] [Accepted: 03/11/2022] [Indexed: 06/15/2023]
Abstract
PREMISE To avoid inbreeding depression, plants have evolved diverse breeding systems to favor outcrossing, such as self-incompatibility. However, changes in biotic and abiotic conditions can result in selective pressures that lead to a breakdown in self-incompatibility. The shift to increased selfing is commonly associated with reduced floral features, lower attractiveness to pollinators, and increased inbreeding. We tested the hypothesis that the loss of self-incompatibility, a shift to self-fertilization (autogamy), and concomitant evolution of the selfing syndrome (reduction in floral traits associated with cross-fertilization) will lead to increased inbreeding and population differentiation in Oenothera primiveris. Across its range, this species exhibits a shift in its breeding system and floral traits from a self-incompatible population with large flowers to self-compatible populations with smaller flowers. METHODS We conducted a breeding system assessment, evaluated floral traits in the field and under controlled conditions, and measured population genetic parameters using RADseq data. RESULTS Our results reveal a bimodal transition to the selfing syndrome from the west to the east of the range of O. primiveris. This shift includes variation in the breeding system and the mating system, a reduction in floral traits (flower diameter, herkogamy, and scent production), a shift to greater autogamy, reduced genetic diversity, and increased inbreeding. CONCLUSIONS The observed variation highlights the importance of range-wide studies to understand breeding system variation and the evolution of the selfing syndrome within populations and species.
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Affiliation(s)
- Anita Cisternas‐Fuentes
- Negaunee Institute for Plant Conservation Science and ActionChicago Botanic Garden1000 Lake Cook RoadGlencoeIllinois60035USA
- Plant Biology and ConservationNorthwestern University2205 Tech DriveEvanstonIllinois60208USA
- Department of Biological ScienceClemson University132 Long HallClemsonSouth Carolina29631USA
| | - Tania Jogesh
- Negaunee Institute for Plant Conservation Science and ActionChicago Botanic Garden1000 Lake Cook RoadGlencoeIllinois60035USA
| | - Geoffrey T. Broadhead
- Department of Entomology and NematologyUniversity of Florida1881 Natural Area DriveGainesvilleFlorida32611USA
| | - Robert A. Raguso
- Department of Neurobiology and BehaviorCornell UniversityW361 Mudd HallIthacaNew York14853USA
| | - Krissa A. Skogen
- Negaunee Institute for Plant Conservation Science and ActionChicago Botanic Garden1000 Lake Cook RoadGlencoeIllinois60035USA
- Plant Biology and ConservationNorthwestern University2205 Tech DriveEvanstonIllinois60208USA
| | - Jeremie B. Fant
- Negaunee Institute for Plant Conservation Science and ActionChicago Botanic Garden1000 Lake Cook RoadGlencoeIllinois60035USA
- Plant Biology and ConservationNorthwestern University2205 Tech DriveEvanstonIllinois60208USA
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22
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Sáez A, Aguilar R, Ashworth L, Gleiser G, Morales CL, Traveset A, Aizen MA. Managed honeybees decrease pollination limitation in self-compatible but not in self-incompatible crops. Proc Biol Sci 2022; 289:20220086. [PMID: 35382601 PMCID: PMC8984806 DOI: 10.1098/rspb.2022.0086] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Modern agriculture is becoming increasingly pollinator-dependent. However, the global stock of domesticated honeybees is growing at a slower rate than its demand, while wild bees are declining worldwide. This uneven scenario of high pollinator demand and low pollinator availability can translate into increasing pollination limitation, reducing the yield of pollinator-dependent crops. However, overall assessments of crop pollination limitation and the factors determining its magnitude are missing. Based on 52 published studies including 30 crops, we conducted a meta-analysis comparing crop yield in pollen-supplemented versus open-pollinated flowers. We assessed the overall magnitude of pollination limitation and whether this magnitude was influenced by (i) the presence/absence of managed honeybees, (ii) crop compatibility system (i.e. self-compatible/self-incompatible) and (iii) the interaction between these two factors. Overall, pollen supplementation increased yield by approximately 34%, indicating sizable pollination limitation. Deployment of managed honeybees and self-compatibility were associated with lower pollination limitation. Particularly, active honeybee management decreased pollination limitation among self-compatible but apparently not among self-incompatible crops. These findings indicate that current pollination regimes are, in general, inadequate to maximize crop yield, even when including managed honeybees, and stress the need of transforming the pollination management paradigm of agricultural landscapes.
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Affiliation(s)
- Agustín Sáez
- Grupo de Ecología de la Polinización (ECOPOL), Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA), CONICET-Universidad Nacional del Comahue, Quintral 1250, Bariloche 8400, Rio Negro, Argentina
| | - Ramiro Aguilar
- Instituto Multidisciplinario de Biología Vegetal, Universidad Nacional de Córdoba - CONICET, Córdoba, Argentina.,Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE), Universidad Nacional Autónoma de México, 58190 Morelia, México
| | - Lorena Ashworth
- Instituto Multidisciplinario de Biología Vegetal, Universidad Nacional de Córdoba - CONICET, Córdoba, Argentina.,Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE), Universidad Nacional Autónoma de México, 58190 Morelia, México
| | - Gabriela Gleiser
- Grupo de Ecología de la Polinización (ECOPOL), Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA), CONICET-Universidad Nacional del Comahue, Quintral 1250, Bariloche 8400, Rio Negro, Argentina
| | - Carolina L Morales
- Grupo de Ecología de la Polinización (ECOPOL), Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA), CONICET-Universidad Nacional del Comahue, Quintral 1250, Bariloche 8400, Rio Negro, Argentina
| | - Anna Traveset
- Global Change Research Group, Mediterranean Institute for Advanced Studies, 07190 Esporles, Mallorca, Balearic Islands, Spain
| | - Marcelo A Aizen
- Grupo de Ecología de la Polinización (ECOPOL), Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA), CONICET-Universidad Nacional del Comahue, Quintral 1250, Bariloche 8400, Rio Negro, Argentina.,Wissenschaftskolleg zu Berlin, Berlin 14193, Germany
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23
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Kottler EJ, Gedan KB. Sexual reproduction is light-limited as marsh grasses colonize maritime forest. AMERICAN JOURNAL OF BOTANY 2022; 109:514-525. [PMID: 35244201 DOI: 10.1002/ajb2.1831] [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: 05/28/2021] [Revised: 01/24/2022] [Accepted: 02/08/2022] [Indexed: 06/14/2023]
Abstract
Climate change is driving abiotic shifts that can threaten the conservation of foundation species and the habitats they support. Directional range shifting is one mechanism of escape, but requires the successful colonization of habitats where interspecific interactions may differ from those to which a species has adapted. For plants with multiple reproductive strategies, these range-edge interactions may alter the investment or allocation toward a given reproductive strategy. In this study, we quantified sexual reproduction of the clonal marsh grass Spartina patens across an inland colonization front into maritime forest being driven by sea-level rise. We find that flowering is variable across S. patens meadows, but consistently reduced in low light conditions like those of the forest understory. Observational surveys of S. patens flowering at four sites in the Delmarva Peninsula agreed with the results of two experimental manipulations of light availability (shading experiment in S. patens-dominated marsh and a forest dieback manipulation). These three approaches pinpointed light limitation as a principal control on S. patens flowering capacity, suggesting that light competition with taller upland species can suppress S. patens flowering along its upland migration front. Consequently, all propagation in shaded conditions must occur clonally or via seeds from the marsh, a reproductive restriction that could limit the potential for local adaptation and reduce genetic diversity. Future research is needed to determine whether the lack of flowering is the result of a trade-off between sexual and clonal reproduction or results from insufficient photosynthetic products needed to achieve either reproductive method.
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Affiliation(s)
- Ezra J Kottler
- Department of Biological Sciences, George Washington University, 800 22nd ST NW, Suite 6000, Washington, D.C. 20052, USA
| | - Keryn B Gedan
- Department of Biological Sciences, George Washington University, 800 22nd ST NW, Suite 6000, Washington, D.C. 20052, USA
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24
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Kolis KM, Berg CS, Nelson TC, Fishman L. Population genomic consequences of life-history and mating system adaptation to a geothermal soil mosaic in yellow monkeyflowers. Evolution 2022; 76:765-781. [PMID: 35266558 DOI: 10.1111/evo.14469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 01/13/2022] [Accepted: 01/26/2022] [Indexed: 01/21/2023]
Abstract
Local selection can promote phenotypic divergence despite gene flow across habitat mosaics, but adaptation itself may generate substantial barriers to genetic exchange. In plants, life-history, phenology, and mating system divergence have been proposed to promote genetic differentiation in sympatry. In this study, we investigate phenotypic and genetic variation in Mimulus guttatus (yellow monkeyflowers) across a geothermal soil mosaic in Yellowstone National Park (YNP). Plants from thermal annual and nonthermal perennial habitats were heritably differentiated for life-history and mating system traits, consistent with local adaptation to the ephemeral thermal-soil growing season. However, genome-wide genetic variation primarily clustered plants by geographic region, with little variation sorting by habitat. The one exception was an extreme thermal population also isolated by a 200 m geographical gap of no intermediate habitat. Individual inbreeding coefficients (FIS ) were higher (and predicted by trait variation) in annual plants and annual pairs showed greater isolation by distance at local (<1 km) scales. Finally, YNP adaptation does not reuse a widespread inversion that underlies M. guttatus life-history ecotypes range-wide, suggesting a novel genetic mechanism. Overall, this work suggests that life-history and mating system adaptation strong enough to shape individual mating patterns does not necessarily generate incipient speciation without geographical barriers.
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Affiliation(s)
- Kory M Kolis
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812.,Current Address: O'Connor Center for the Rocky Mountain West, University of Montana, Missoula, MT, 59812
| | - Colette S Berg
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812
| | - Thomas C Nelson
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812.,Current Address: Embark Veterinary, Inc., Boston, Massachusetts, 02210
| | - Lila Fishman
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812
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25
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Tian H, Harder LD, Wang A, Zhang D, Liao W. Habitat effects on reproductive phenotype, pollinator behavior, fecundity, and mating outcomes of a bumble bee-pollinated herb. AMERICAN JOURNAL OF BOTANY 2022; 109:470-485. [PMID: 35244204 PMCID: PMC9314043 DOI: 10.1002/ajb2.1826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
PREMISE Fecundity and mating outcomes commonly differ among plant populations occupying contrasting environments. If self-pollination occurs primarily among flowers within plants, contrasting reproductive outcomes among populations must reflect environmental effects on plant-pollinator interactions. Specifically, local conditions could affect features of plant phenotypes that influence pollinator behavior, in turn modifying plant reproductive outcomes. METHODS We compared phenotypes, pollinator abundance and behavior, and female fecundity and mating in two meadow populations and two forest populations of Aconitum kusnezoffii within 3 km of each other. Mating outcomes were assessed using microsatellites. RESULTS Meadow plants generally produced more, shorter ramets with more, larger flowers, but less nectar per flower than forest plants. These differences likely largely represent phenotypic plasticity. Individual bumble bees visited more flowers on forest plants, likely because the more abundant bees in the meadows depleted nectar availability, as indicated by briefer visits to individual flowers. Despite similar fruit set in both habitats, forest plants set more seeds per fruit. Nevertheless, meadow plants produced more seeds overall, owing to sevenfold greater flower production. Consistent with individual bees visiting fewer flowers on meadow plants, more of their seeds were outcrossed. However, the outcrossed seeds of forest plants included more male mates. CONCLUSIONS Reproductive outcomes can vary among populations of animal-pollinated plants as a result of differences in the availability of effective pollinators and environmental effects on plant phenotypes, and their functional consequences for pollinator behavior that governs pollen dispersal.
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Affiliation(s)
- Hao Tian
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Ministry of Education Key Laboratory for Biodiversity Science and Ecological EngineeringBeijing Normal UniversityBeijing100875China
| | - Lawrence D. Harder
- Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaT2N 1N4Canada
| | - Ai‐Ying Wang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Ministry of Education Key Laboratory for Biodiversity Science and Ecological EngineeringBeijing Normal UniversityBeijing100875China
| | - Da‐Yong Zhang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Ministry of Education Key Laboratory for Biodiversity Science and Ecological EngineeringBeijing Normal UniversityBeijing100875China
| | - Wan‐Jin Liao
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Ministry of Education Key Laboratory for Biodiversity Science and Ecological EngineeringBeijing Normal UniversityBeijing100875China
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26
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Zhang W, Hu YF, He X, Zhou W, Shao JW. Evolution of Autonomous Selfing in Marginal Habitats: Spatiotemporal Variation in the Floral Traits of the Distylous Primula wannanensis. FRONTIERS IN PLANT SCIENCE 2021; 12:781281. [PMID: 34975966 PMCID: PMC8716950 DOI: 10.3389/fpls.2021.781281] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 11/09/2021] [Indexed: 06/08/2023]
Abstract
Outcrossing plant species are more likely to exhibit autonomous selfing in marginal habitats to ensure reproduction under conditions of limited pollinator and/or mate availability. Distyly is a classical paradigm that promotes outcrossing; however, little is known about the variation in floral traits associated with distylous syndrome in marginal populations. In this study, we compared the variation in floral traits including stigma and anther height, corolla tube length, herkogamy, and corolla diameter between the central and peripheral populations of the distylous Primula wannanensis, and assessed the variation of floral traits at early and late florescence stages for each population. To evaluate the potential consequences of the variation in floral traits on the mating system, we investigated seed set in each population under both open-pollinated and pollinator-excluded conditions. The flower size of both short- and long-styled morphs was significantly reduced in late-opening flowers compared with early opening flowers in both central and peripheral populations. Sex-organ reciprocity was perfect in early opening flowers; however, it was largely weakened in the late-opening flowers of peripheral populations compared with central populations. Of these flowers, disproportionate change in stigma height (elongated in S-morph and shortened in L-morph) was the main cause of reduced herkogamy, and seed set was fairly high under pollinator-excluded condition. Our results provide empirical support for the hypothesis on the evolution of delayed autonomous selfing in marginal populations of distylous species. Unsatisfactory pollinator service is likely to have promoted reproductive assurance of distylous plants with largely reduced herkogamy mimicking "homostyles."
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Affiliation(s)
- Wei Zhang
- College of Life Sciences, Anhui Normal University, Wuhu, China
- Provincial Key Laboratory of Conservation and Utilization of Biological Resources, Wuhu, China
| | - Ying Feng Hu
- College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Xiao He
- College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Wei Zhou
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- Lijiang Forest Biodiversity National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang, China
| | - Jian Wen Shao
- College of Life Sciences, Anhui Normal University, Wuhu, China
- Provincial Key Laboratory of Conservation and Utilization of Biological Resources, Wuhu, China
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27
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Prior CJ, Busch JW. Selfing rate variation within species is unrelated to life-history traits or geographic range position. AMERICAN JOURNAL OF BOTANY 2021; 108:2294-2308. [PMID: 34632564 DOI: 10.1002/ajb2.1766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 08/25/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
PREMISE In plants, populations and species vary widely along the continuum from outcrossing to selfing. Life-history traits and ecological circumstances influence among-species variation in selfing rates, but their general role in explaining intraspecific variation is unknown. Using a database of plant species, we test whether life-history traits, geographic range position, or abundance predict selfing rate variation among populations. METHODS We identified species where selfing rates were estimated in at least three populations at known locations. Two key life-history traits (generation time and growth form) were used to predict within-species selfing rate variation. Populations sampled within a species' native range were assessed for proximity to the nearest edge and abundance. Finally, we conducted linear and segmented regressions to determine functional relationships between selfing rate and geographic range position within species. RESULTS Selfing rates for woody species varied less than for herbs, which is explained by the lower average selfing rate of woody species. Relationships between selfing and peripherality or abundance significantly varied among species in their direction and magnitude. However, there was no general pattern of increased selfing toward range edges. A power analysis shows that tests of this hypothesis require studying many (i.e., 40+) populations. CONCLUSIONS Intraspecific variation in plant mating systems is often substantial yet remains difficult to explain. Beyond sampling more populations, future tests of biogeographic hypotheses will benefit from phylogeographic information concerning specific range edges, the study of traits influencing mating system (e.g., herkogamy), and measures of abundance at local scales (e.g., population density).
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Affiliation(s)
- Carly J Prior
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
| | - Jeremiah W Busch
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
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28
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Chaves CJN, Leal BSS, Rossatto DR, Berger U, Palma-Silva C. Deforestation is the turning point for the spreading of a weedy epiphyte: an IBM approach. Sci Rep 2021; 11:20397. [PMID: 34650134 PMCID: PMC8516858 DOI: 10.1038/s41598-021-99798-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 09/27/2021] [Indexed: 11/08/2022] Open
Abstract
The rapid spread of many weeds into intensely disturbed landscapes is boosted by clonal growth and self-fertilization strategies, which conversely increases the genetic structure of populations. Here, we use empirical and modeling approaches to evaluate the spreading dynamics of Tillandsia recurvata (L.) L. populations, a common epiphytic weed with self-reproduction and clonal growth widespread in dry forests and deforested landscapes in the American continent. We introduce the TRec model, an individual-based approach to simulate the spreading of T. recurvata over time and across landscapes subjected to abrupt changes in tree density with the parameters adjusted according to the empirical genetic data based on microsatellites genotypes. Simulations with this model showed that the strong spatial genetic structure observed from empirical data in T. recurvata can be explained by a rapid increase in abundance and gene flow followed by stabilization after ca. 25 years. TRec model's results also indicate that deforestation is a turning point for the rapid increase in both individual abundance and gene flow among T. recurvata subpopulations occurring in formerly dense forests. Active reforestation can, in turn, reverse such a scenario, although with a milder intensity. The genetic-based study suggests that anthropogenic changes in landscapes may strongly affect the population dynamics of species with 'weedy' traits.
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Affiliation(s)
- Cleber Juliano Neves Chaves
- Programa de Pós-Graduação em Ecologia e Biodiversidade, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, 13506-900, Brazil.
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, 13083-862, Brazil.
| | - Bárbara Simões Santos Leal
- Programa de Pós-Graduação em Ecologia e Biodiversidade, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, 13506-900, Brazil
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, 13083-862, Brazil
| | - Davi Rodrigo Rossatto
- Departamento de Biologia, Universidade Estadual Paulista, Jaboticabal, 14884-900, Brazil
| | - Uta Berger
- Institute of Forest Growth and Computer Sciences, Technische Universität Dresden, 01737, Tharandt, Germany
| | - Clarisse Palma-Silva
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, 13083-862, Brazil
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29
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Lesaffre T. Population-level consequences of inheritable somatic mutations and the evolution of mutation rates in plants. Proc Biol Sci 2021; 288:20211127. [PMID: 34493080 DOI: 10.1098/rspb.2021.1127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Inbreeding depression, that is the decrease in fitness of inbred relative to outbred individuals, was shown to increase strongly as life expectancy increases in plants. Because plants are thought to not have a separated germline, it was proposed that this pattern could be generated by somatic mutations accumulating during growth, since larger and more long-lived species have more opportunities for mutations to accumulate. A key determinant of the role of somatic mutations is the rate at which they occur, which probably differs between species because mutation rates may evolve differently in species with constrasting life histories. In this paper, I study the evolution of the mutation rates in plants, and consider the population-level consequences of inheritable somatic mutations given this evolution. I show that despite substantially lower somatic and meiotic mutation rates, more long-lived species still tend to accumulate larger amounts of deleterious mutations because of the increased number of opportunities they have to acquire mutations during growth, leading to higher levels of inbreeding depression in these species. However, the magnitude of this increase depends strongly on how mutagenic meiosis is relative to growth, to the point of being close to non-existent in some situations.
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Affiliation(s)
- Thomas Lesaffre
- CNRS, Univ. Lille, UMR 8198 - Evo-Eco-Paleo, F-59000 Lille, France
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30
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Ma Y, Barrett SCH, Wang FY, Deng JC, Bai WN. Do annual and perennial populations of an insect-pollinated plant species differ in mating system? ANNALS OF BOTANY 2021; 127:853-864. [PMID: 33035305 PMCID: PMC8225283 DOI: 10.1093/aob/mcaa178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND AIMS Theory predicts that outcrossing should be more prevalent among perennials than annuals, a pattern confirmed by comparative evidence from diverse angiosperm families. However, intraspecific comparisons between annual and perennial populations are few because such variation is uncommon among flowering plants. Here, we test the hypothesis that perennial populations outcross more than annual populations by investigating Incarvillea sinensis, a wide-ranging insect-pollinated herb native to China. The occurrence of both allopatric and sympatric populations allows us to examine the stability of mating system differences between life histories under varying ecological conditions. METHODS We estimated outcrossing rates and biparental inbreeding in 16 allopatric and five sympatric populations in which both life histories coexisted using 20 microsatellite loci. In each population we measured height, branch number, corolla size, tube length and herkogamy for ~30 individuals. In a sympatric population, we recorded daily flower number, pollinator visitation and the fruit and seed set of annual and perennial plants. KEY RESULTS As predicted, outcrossing rates (t) were considerably higher in perennial (mean = 0.76) than annual (mean = 0.09) populations. This difference in mating system was also maintained at sympatric sites where plants grew intermixed. In both allopatric and sympatric populations the degree of herkogamy was consistently larger in outcrossing than selfing plants. Perennials were more branched, with more and larger flowers than in annuals. In a sympatric population, annuals had a significantly higher fruit and seed set than perennials. CONCLUSIONS Genetically based differences in herkogamy between annuals and perennials appear to play a key role in governing outcrossing rates in populations, regardless of variation in local ecological conditions. The maintenance of mating system and life history trait differentiation between perennial and annual populations of I. sinensis probably results from correlated evolution in response to local environmental conditions.
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Affiliation(s)
- Yue Ma
- State Key Laboratory of Earth Surface Processes and Resource Ecology and Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Spencer C H Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - Fang-Yuan Wang
- State Key Laboratory of Earth Surface Processes and Resource Ecology and Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Jun-Chen Deng
- State Key Laboratory of Earth Surface Processes and Resource Ecology and Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Wei-Ning Bai
- State Key Laboratory of Earth Surface Processes and Resource Ecology and Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
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31
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Wang Y, Luo A, Lyu T, Dimitrov D, Xu X, Freckleton RP, Li Y, Su X, Li Y, Liu Y, Sandanov D, Li Q, Hao Z, Liu S, Wang Z. Global distribution and evolutionary transitions of angiosperm sexual systems. Ecol Lett 2021; 24:1835-1847. [PMID: 34121305 DOI: 10.1111/ele.13815] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/01/2021] [Accepted: 05/03/2021] [Indexed: 01/08/2023]
Abstract
Angiosperm sexual systems are fundamental to the evolution and distribution of plant diversity, yet spatiotemporal patterns in angiosperm sexual systems and their drivers remain poorly known. Using data on sexual systems and distributions of 68453 angiosperm species, we present the first global maps of sexual system frequencies and evaluate sexual system evolution during the Cenozoic. Frequencies of dioecy and monoecy increase with latitude, while hermaphrodites are more frequent in warm and arid regions. Transitions to dioecy from other states were higher than to hermaphroditism, but transitions away from dioecy increased since the Cenozoic, suggesting that dioecy is not an evolutionary end point. Transitions between hermaphroditism and dioecy increased, while transitions to monoecy decreased with paleo-temperature when paleo-temperature >0℃. Our study demonstrates the biogeography of angiosperm sexual systems from a macroecological perspective, and enhances our understanding of plant diversity patterns and their response to climate change.
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Affiliation(s)
- Yunyun Wang
- Faculty of Life Science and Technology, Central South University of Forestry and Technology and National Engineering Laboratory for Applied Forest Ecological Technology in Southern China, Changsha, China.,Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Ao Luo
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Tong Lyu
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Dimitar Dimitrov
- Department of Natural History, University Museum of Bergen, University of Bergen, Bergen, Norway
| | - Xiaoting Xu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, China
| | - Robert P Freckleton
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - Yaoqi Li
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Xiangyan Su
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yichao Li
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yunpeng Liu
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Denis Sandanov
- Institute of General and Experimental Biology, Siberian Branch of Russian Academy of Science, Ulan-Ude, Russia
| | - Qingjun Li
- Laboratory of Ecology and Evolutionary Biology, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan, China
| | - Zhanqing Hao
- Research Center for Ecology and Environmental Sciences, Xian, China
| | - Shuguang Liu
- Faculty of Life Science and Technology, Central South University of Forestry and Technology and National Engineering Laboratory for Applied Forest Ecological Technology in Southern China, Changsha, China
| | - Zhiheng Wang
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
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32
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Monks L, Standish R, McArthur S, Dillon R, Byrne M, Coates D. Genetic and mating system assessment of translocation success of the long‐lived perennial shrub
Lambertia orbifolia
(Proteaceae). Restor Ecol 2021. [DOI: 10.1111/rec.13369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Leonie Monks
- Biodiversity Conservation Science, Department of Biodiversity Conservation and Attractions Locked Bag 104, Bentley Delivery Centre, Bentley WA 6983 Australia
- Environmental and Conservation Sciences Murdoch University 90 South Street, Murdoch WA 6150 Australia
| | - Rachel Standish
- Environmental and Conservation Sciences Murdoch University 90 South Street, Murdoch WA 6150 Australia
| | - Shelley McArthur
- Biodiversity Conservation Science, Department of Biodiversity Conservation and Attractions Locked Bag 104, Bentley Delivery Centre, Bentley WA 6983 Australia
| | - Rebecca Dillon
- Biodiversity Conservation Science, Department of Biodiversity Conservation and Attractions Locked Bag 104, Bentley Delivery Centre, Bentley WA 6983 Australia
| | - Margaret Byrne
- Biodiversity Conservation Science, Department of Biodiversity Conservation and Attractions Locked Bag 104, Bentley Delivery Centre, Bentley WA 6983 Australia
| | - David Coates
- Biodiversity Conservation Science, Department of Biodiversity Conservation and Attractions Locked Bag 104, Bentley Delivery Centre, Bentley WA 6983 Australia
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33
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González-Robles A, García C, Salido T, Manzaneda AJ, Rey PJ. Extensive pollen-mediated gene flow across intensively managed landscapes in an insect-pollinated shrub native to semiarid habitats. Mol Ecol 2021; 30:3408-3421. [PMID: 33966307 DOI: 10.1111/mec.15950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 11/28/2022]
Abstract
Our knowledge of the impact of landscape fragmentation on gene flow patterns is mainly drawn from tropical and temperate ecosystems, where landscape features, such as the distance of a tree to the forest edge, drive connectivity and mating patterns. Yet, the structure of arid and semiarid plant communities - with open canopies and a scattered distribution of trees - differs greatly from those that are well-characterized in the literature. As a result, we ignore whether the documented consequences of landscape fragmentation on plant mating and gene flow patterns also hold for native plant communities in arid and semiarid regions. We investigated the relative contribution of plant traits, pollinator activity, and individual neighbourhood in explaining variation in mating and gene flow patterns of an insect-pollinated semiarid arborescent shrub, Ziziphus lotus, at three sites embedded in highly altered agriculture landscapes. We used 14 SSRs, seed paternity analyses, and individual mixed effect mating models (MEMMi) to estimate the individual mating variables and the pollen dispersal kernel at each site. Individual spatial location, flower density, and floral visitation rate explained most of the variation of mating variables. Unexpectedly, individual correlated paternity was very low and shrubs surrounded by the most degraded matrix exhibited an increased fraction of pollen immigration and a high effective number of pollen donors per mother shrub. Overall, our results reveal that an active pollinator assemblage ensures highly efficient mating, and maintains pollen-mediated gene flow and notable connectivity levels, even in highly altered landscapes, potentially halting genetic isolation within and between distant sites.
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Affiliation(s)
- Ana González-Robles
- Departamento de Biología Animal, Biología Vegetal y Ecología, Universidad de Jaén, Jaén, Spain
| | - Cristina García
- Department of Evolution, Ecology, and Behaviour, Institute of Integrative Biology, University of Liverpool, Liverpool, UK.,Plant Biology, CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Universidade do Porto, Vairão, Portugal
| | - Teresa Salido
- Departamento de Biología Animal, Biología Vegetal y Ecología, Universidad de Jaén, Jaén, Spain.,Instituto Interuniversitario del Sistema Tierra en Andalucía (IISTA-UJA), Jaén, Spain
| | - Antonio J Manzaneda
- Departamento de Biología Animal, Biología Vegetal y Ecología, Universidad de Jaén, Jaén, Spain.,Instituto Interuniversitario del Sistema Tierra en Andalucía (IISTA-UJA), Jaén, Spain
| | - Pedro J Rey
- Departamento de Biología Animal, Biología Vegetal y Ecología, Universidad de Jaén, Jaén, Spain.,Instituto Interuniversitario del Sistema Tierra en Andalucía (IISTA-UJA), Jaén, Spain
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Kudo G, Shibata A. Is increased male flower production a strategy for avoidance of predispersal seed predation in andromonoecious plants? Ecol Evol 2021; 11:5646-5656. [PMID: 34026036 PMCID: PMC8131791 DOI: 10.1002/ece3.7468] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 02/28/2021] [Accepted: 03/03/2021] [Indexed: 11/06/2022] Open
Abstract
Floral gender in angiosperms often varies within and among populations. We conducted a field survey to test how predispersal seed predation affects sex allocation in an andromonoecious alpine herb Peucedanum multivittatum. We compared plant size, male and perfect flower production, fruit set, and seed predation rate over three years among nine populations inhabiting diverse snowmelt conditions in alpine meadows. Flowering period of individual populations varied from mid-July to late August reflecting the snowmelt time. Although perfect flower and fruit productions increased with plant size, size dependency of male flower production was less clear. The number of male flowers was larger in the early-flowering populations, while the number of perfect flowers increased in the late-flowering populations. Thus, male-biased sex allocation was common in the early-flowering populations. Fruit-set rates varied among populations and between years, irrespective of flowering period. Fruit-set success of individual plants increased with perfect flower number, but independent of male flower number. Seed predation by lepidopteran larvae was intense in the early-flowering populations, whereas predation damage was absent in the late-flowering populations, reflecting the extent of phenological matching between flowering time of host plants and oviposition period of predator moths. Seed predation rate was independent of male and perfect flower numbers of individual plants. Thus, seed predation is a stochastic event in each population. There was a clear correlation between the proportion of male flowers and the intensity of seed predation among populations. These results suggest that male-biased sex allocation could be a strategy to reduce seed predation damage but maintain the effort as a pollen donor under intensive seed predation.
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Affiliation(s)
- Gaku Kudo
- Faculty of Environmental Earth ScienceHokkaido UniversitySapporoJapan
| | - Akari Shibata
- Faculty of Environmental Earth ScienceHokkaido UniversitySapporoJapan
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35
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Unexpectedly low paternal diversity is associated with infrequent pollinator visitation for a bird-pollinated plant. Oecologia 2021; 196:937-950. [PMID: 33870456 DOI: 10.1007/s00442-021-04906-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 03/23/2021] [Indexed: 10/21/2022]
Abstract
The behaviour of pollinators has important consequences for plant mating. Nectar-feeding birds often display behaviour that results in more pollen carryover than insect pollinators, which is predicted to result in frequent outcrossing and high paternal diversity for bird-pollinated plants. We tested this prediction by quantifying mating system parameters and bird visitation in three populations of an understory bird-pollinated herb, Anigozanthos humilis (Haemodoraceae). Microsatellite markers were used to genotype 131 adult plants, and 211 seeds from 23 maternal plants, from three populations. While outcrossing rates were high, estimates of paternal diversity were surprisingly low compared with other bird-pollinated plants. Despite nectar-feeding birds being common at the study sites, visits to A. humilis flowers were infrequent (62 visits over 21,552 recording hours from motion-triggered cameras, or equivalent to one visit per flower every 10 days), and the majority (76%) were by a single species, the western spinebill Acanthorhynchus superciliosus (Meliphagidae). Pollen counts from 30 captured honeyeaters revealed that A. humilis comprised just 0.3% of the total pollen load. For 10 western spinebills, A. humilis pollen comprised only 4.1% of the pollen load, which equated to an average of 3.9 A. humilis pollen grains per bird. Taken together, our findings suggest that low visitation rates and low pollen loads of floral visitors have led to the low paternal diversity observed in this understory bird-pollinated herb. As such, we shed new light on the conditions that can lead to departures from high paternal diversity for plants competing for the pollination services of generalist nectar-feeding birds.
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36
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Bilas RD, Bretman A, Bennett T. Friends, neighbours and enemies: an overview of the communal and social biology of plants. PLANT, CELL & ENVIRONMENT 2021; 44:997-1013. [PMID: 33270936 DOI: 10.1111/pce.13965] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 11/06/2020] [Accepted: 11/26/2020] [Indexed: 05/21/2023]
Abstract
Plants were traditionally seen as rather passive actors in their environment, interacting with each other only in so far as they competed for the same resources. In the last 30 years, this view has been spectacularly overturned, with a wealth of evidence showing that plants actively detect and respond to their neighbours. Moreover, there is evidence that these responses depend on the identity of the neighbour, and that plants may cooperate with their kin, displaying social behaviour as complex as that observed in animals. These plant-plant interactions play a vital role in shaping natural ecosystems, and are also very important in determining agricultural productivity. However, in terms of mechanistic understanding, we have only just begun to scratch the surface, and many aspects of plant-plant interactions remain poorly understood. In this review, we aim to provide an overview of the field of plant-plant interactions, covering the communal interactions of plants with their neighbours as well as the social behaviour of plants towards their kin, and the consequences of these interactions. We particularly focus on the mechanisms that underpin neighbour detection and response, highlighting both progress and gaps in our understanding of these fascinating but previously overlooked interactions.
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Affiliation(s)
- Roza D Bilas
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Amanda Bretman
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Tom Bennett
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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37
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Christopher DA, Karron JD, Semski WR, Smallwood PA, Trapnell DW, Mitchell RJ. Selfing rates vary with floral display, pollinator visitation and plant density in natural populations of Mimulus ringens. J Evol Biol 2021; 34:803-815. [PMID: 33704852 PMCID: PMC8252063 DOI: 10.1111/jeb.13781] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 02/01/2021] [Accepted: 02/25/2021] [Indexed: 11/27/2022]
Abstract
Variation in selfing rates within and among populations of hermaphroditic flowering plants can strongly influence the evolution of reproductive strategies and the genetic structure of populations. This intraspecific variation in mating patterns may reflect both genetic and ecological factors, but the relative importance of these factors remains poorly understood. Here, we explore how selfing in 13 natural populations of the perennial wildflower Mimulus ringens is influenced by (a) pollinator visitation, an ecological factor, and (b) floral display, a trait with a genetic component that also responds to environmental variation. We also explore whether genetically based floral traits, including herkogamy, affect selfing. We found substantial variation among populations in selfing rate (0.13–0.55). Selfing increased strongly and significantly with floral display, among as well as within populations. Selfing also increased at sites with lower pollinator visitation and low plant density. However, selfing was not correlated with floral morphology. Overall, these results suggest that pollinator visitation and floral display, two factors that interact to affect geitonogamous pollinator movements, can influence the selfing rate. This study identifies mechanisms that may play a role in maintaining selfing rate variation among populations.
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Affiliation(s)
- Dorothy A Christopher
- Department of Biological Sciences, University of Wisconsin - Milwaukee, Milwaukee, WI, USA
| | - Jeffrey D Karron
- Department of Biological Sciences, University of Wisconsin - Milwaukee, Milwaukee, WI, USA
| | - Wendy R Semski
- Department of Biological Sciences, University of Wisconsin - Milwaukee, Milwaukee, WI, USA
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38
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Edwards CE, Tessier BC, Swift JF, Bassüner B, Linan AG, Albrecht MA, Yatskievych GA. Conservation genetics of the threatened plant species Physaria filiformis (Missouri bladderpod) reveals strong genetic structure and a possible cryptic species. PLoS One 2021; 16:e0247586. [PMID: 33705416 PMCID: PMC7951829 DOI: 10.1371/journal.pone.0247586] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 02/09/2021] [Indexed: 11/19/2022] Open
Abstract
Understanding genetic diversity and structure in a rare species is critical for prioritizing both in situ and ex situ conservation efforts. One such rare species is Physaria filiformis (Brassicaceae), a threatened, winter annual plant species. The species has a naturally fragmented distribution, occupying three different soil types spread across four disjunct geographical locations in Missouri and Arkansas. The goals of this study were to understand: (1) whether factors associated with fragmentation and small population size (i.e., inbreeding, genetic drift or genetic bottlenecks) have reduced levels of genetic diversity, (2) how genetic variation is structured and which factors have influenced genetic structure, and (3) how much extant genetic variation of P. filiformis is currently publicly protected and the implications for the development of conservation strategies to protect its genetic diversity. Using 16 microsatellite markers, we genotyped individuals from 20 populations of P. filiformis from across its geographical range and one population of Physaria gracilis for comparison and analyzed genetic diversity and structure. Populations of P. filiformis showed comparable levels of genetic diversity to its congener, except a single population in northwest Arkansas showed evidence of a genetic bottleneck and two populations in the Ouachita Mountains of Arkansas showed lower genetic variation, consistent with genetic drift. Populations showed isolation by distance, indicating that migration is geographically limited, and analyses of genetic structure grouped individuals into seven geographically structured genetic clusters, with geographic location/spatial separation showing a strong influence on genetic structure. At least one population is protected for all genetic clusters except one in north-central Arkansas, which should therefore be prioritized for protection. Populations in the Ouachita Mountains were genetically divergent from the rest of P. filiformis; future morphological analyses are needed to identify whether it merits recognition as a new, extremely rare species.
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Affiliation(s)
- Christine E. Edwards
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, Missouri, United States of America
| | - Brooke C. Tessier
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, Missouri, United States of America
- Department of Cellular and Molecular Biology, Winona State University, Winona, Minnesota, United States of America
| | - Joel F. Swift
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, Missouri, United States of America
| | - Burgund Bassüner
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, Missouri, United States of America
| | - Alexander G. Linan
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, Missouri, United States of America
- Department of Biology, Saint Louis University, St. Louis, Missouri, United States of America
| | - Matthew A. Albrecht
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, Missouri, United States of America
| | - George A. Yatskievych
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, Missouri, United States of America
- Plant Resources Center, University of Texas at Austin, Austin, Texas, United States of America
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39
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Kulbaba MW, Shaw RG. Lifetime Fitness through Female and Male Function: Influences of Genetically Effective Population Size and Density. Am Nat 2021; 197:434-447. [PMID: 33755534 DOI: 10.1086/713067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractAn individual's lifetime fitness and patterns of mating between individuals are interdependent features of sexual organisms. Mating systems (outcrossing vs. selfing or mating between close relatives) can affect the distribution of offspring fitness, which generally declines with inbreeding, which in turn is related to a population's genetically effective size (Ne). Fitness and mating patterns are also expected to vary with proximity of mates (i.e., population density). Consequently, density and Ne may influence demographic and genetic changes over generations and interact in their effects. Here, we report an experiment designed to assess the influence of these two population-level properties on mating system and lifetime fitness. In experimental arrays under quasi-natural conditions, we varied the density and Ne of the hermaphroditic annual legume Chamaecrista fasciculata. We recorded components of fitness for each individual and employed microsatellite markers to estimate outcrossing and assign paternity. We used aster analyses to estimate lifetime fitness for genetic families using female (seeds set) and male (seeds sired) reproduction as fitness measures. With estimates from these analyses, we assessed the evidence for a trade-off between fitness attained through female versus male function, but we found none. Lifetime fitness increased with density, especially under high Ne. Outcrossing rates increased with density under high Ne but declined modestly with density under low Ne. Our results show that density and Ne have strong direct effects on fitness and mating systems, with negative fitness effects of low Ne limiting the positive effects of increasing density. These findings highlight the importance of the interactive effects of density and Ne on lifetime fitness.
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40
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Van Etten ML, Soble A, Baucom RS. Variable inbreeding depression may explain associations between the mating system and herbicide resistance in the common morning glory. Mol Ecol 2021; 30:5422-5437. [PMID: 33604956 DOI: 10.1111/mec.15852] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 01/18/2021] [Accepted: 02/10/2021] [Indexed: 12/12/2022]
Abstract
Inbreeding depression is a central parameter underlying mating system variation in nature and one that can be altered by environmental stress. Although a variety of systems show that inbreeding depression tends to increase under stressful conditions, we have very little understanding across most organisms how the level of inbreeding depression may change as a result of adaptation to stressors. In this work we examined the potential that inbreeding depression varied among lineages of Ipomoea purpurea artificially evolved to exhibit divergent levels of herbicide resistance. We examined inbreeding depression in a variety of fitness-related traits in both the growth chamber and in the field, and paired this work with an examination of gene expression changes. We found that, while inbreeding depression was present across many of the traits, lineages artificially selected for increased herbicide resistance often showed no evidence of inbreeding depression in the presence of herbicide, and in fact, showed evidence of outbreeding depression in some traits compared to nonselected control lines and lineages selected for increased herbicide susceptibility. Further, at the transcriptome level, the resistant selection lines had differing patterns of gene expression according to breeding type (inbred vs. outcrossed) compared to the control and susceptible selection lines. Our data together indicate that inbreeding depression may be lessened in populations that are adapting to regimes of strong selection.
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Affiliation(s)
- Megan L Van Etten
- Biology Department, Pennsylvania State University, Dunmore, Pennsylvania, USA
| | - Anah Soble
- Ecology and Evolutionary Biology Department, University of Michigan, Ann Arbor, Michigan, USA
| | - Regina S Baucom
- Ecology and Evolutionary Biology Department, University of Michigan, Ann Arbor, Michigan, USA
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41
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Thomas WJW, Anthony JM, Dobrowolski MP, Krauss SL. Optimising the conservation of genetic diversity of the last remaining population of a critically endangered shrub. AOB PLANTS 2021; 13:plab005. [PMID: 33613937 PMCID: PMC7885199 DOI: 10.1093/aobpla/plab005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
An understanding of genetic diversity and the population genetic processes that impact future population viability is vital for the management and recovery of declining populations of threatened species. Styphelia longissima (Ericaceae) is a critically endangered shrub, restricted to a single fragmented population near Eneabba, 250 km north of Perth, Western Australia. For this population, we sought to characterize population genetic variation and its spatial structure, and aspects of the mating portfolio, from which strategies that optimize the conservation of this diversity are identified. A comprehensive survey was carried out and 220 adults, and 106 seedlings from 14 maternal plants, were genotyped using 13 microsatellite markers. Levels of genetic variation and its spatial structure were assessed, and mating system parameters were estimated. Paternity was assigned to the offspring of a subsection of plants, which allowed for the calculation of realized pollen dispersal. Allelic richness and levels of expected heterozygosity were higher than predicted for a small isolated population. Spatial autocorrelation analysis identified fine-scale genetic structure at a scale of 20 m, but no genetic structure was found at larger scales. Mean outcrossing rate (t m = 0.66) reflects self-compatibility and a mixed-mating system. Multiple paternity was low, where 61 % of maternal siblings shared the same sire. Realized pollen dispersal was highly restricted, with 95 % of outcrossing events occurring at 7 m or less, and a mean pollen dispersal distance of 3.8 m. Nearest-neighbour matings were common (55 % of all outcross events), and 97 % of mating events were between the three nearest-neighbours. This study has provided critical baseline data on genetic diversity, mating system and pollen dispersal for future monitoring of S. longissima. Broadly applicable conservation strategies such as implementing a genetic monitoring plan, diluting spatial genetic structure in the natural population, genetically optimizing ex situ collections and incorporating genetic knowledge into translocations will help to manage the future erosion of the high genetic variation detected.
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Affiliation(s)
- William J W Thomas
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- Kings Park Science, Department of Biodiversity, Conservation and Attractions, Kings Park, WA, Australia
| | - Janet M Anthony
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- Kings Park Science, Department of Biodiversity, Conservation and Attractions, Kings Park, WA, Australia
| | - Mark P Dobrowolski
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- Iluka Resources Ltd, Perth, WA, Australia
- Harry Butler Institute, Murdoch University, Murdoch, WA, Australia
| | - Siegfried L Krauss
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- Kings Park Science, Department of Biodiversity, Conservation and Attractions, Kings Park, WA, Australia
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42
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Wang H, Barrett SCH, Li XY, Niu Y, Duan YW, Zhang ZQ, Li QJ. Sexual conflict in protandrous flowers and the evolution of gynodioecy. Evolution 2020; 75:278-293. [PMID: 33080057 DOI: 10.1111/evo.14113] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 09/22/2020] [Accepted: 10/03/2020] [Indexed: 12/26/2022]
Abstract
Sexual interference between male and female function in hermaphrodite plants is reduced by protandry. In environments with insufficient pollinator service, prolongation of male function owing to limited pollen removal could restrict the duration of female function and lower seed production. We provide evidence that this form of sexual conflict has played a role in the spread of females in gynodioecious populations of Cyananthus delavayi in the pollen-limited environments in which this subalpine species occurs. Using field experiments involving artificial pollen removal from the strongly protandrous flowers of hermaphrodites, we demonstrated a trade-off between male- and female-phase duration with no influence on overall floral longevity. Pollen removal at the beginning of anthesis resulted in hermaphrodite seed production matching that of females. In contrast, restricted pollen removal increased the duration of male function at the expense of female function lowering maternal fertility compared to females. This pattern was evident in five populations with females experiencing a twofold average seed fertility advantage compared to hermaphrodites. Gynodioecy often appears to evolve from protandrous ancestors and pollen limitation is widespread in flowering plants suggesting that sexual conflict may play an unappreciated role in the evolution of this form of sexual dimorphism.
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Affiliation(s)
- Hao Wang
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, 650500, China.,Laboratory of Ecology and Evolutionary Biology, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, China
| | - Spencer C H Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, M5S 3B2, Canada
| | - Xue-Yan Li
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, 650500, China.,Laboratory of Ecology and Evolutionary Biology, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, China
| | - Yang Niu
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Yuan-Wen Duan
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Zhi-Qiang Zhang
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, 650500, China.,Laboratory of Ecology and Evolutionary Biology, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, China
| | - Qing-Jun Li
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, 650500, China.,Laboratory of Ecology and Evolutionary Biology, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, China
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43
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Friedman J. The Evolution of Annual and Perennial Plant Life Histories: Ecological Correlates and Genetic Mechanisms. ANNUAL REVIEW OF ECOLOGY, EVOLUTION, AND SYSTEMATICS 2020. [DOI: 10.1146/annurev-ecolsys-110218-024638] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Flowering plants exhibit two principal life-history strategies: annuality (living and reproducing in one year) and perenniality (living more than one year). The advantages of either strategy depend on the relative benefits of immediate reproduction balanced against survivorship and future reproduction. This trade-off means that life-history strategies are associated with particular environments, with annuals being found more often in unpredictable habitats. Annuality and perenniality are the outcome of developmental genetic programs responding to their environment, with perennials being distinguished by their delayed competence to flower and reversion to growth after flowering. Evolutionary transitions between these strategies are frequent and have consequences for mating systems and genome evolution, with perennials being more likely to outcross with higher inbreeding depression and lower rates of molecular evolution. Integrating expectations from life-history theory with knowledge of the developmental genetics of flowering and seasonality is required to understand the mechanisms involved in the evolution of annual and perennial life histories.
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Affiliation(s)
- Jannice Friedman
- Department of Biology, Queen's University, Kingston, Ontario K7L 3N6, Canada
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44
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Wang Y, Lyu T, Luo A, Li Y, Liu Y, Freckleton RP, Liu S, Wang Z. Spatial Patterns and Drivers of Angiosperm Sexual Systems in China Differ Between Woody and Herbaceous Species. FRONTIERS IN PLANT SCIENCE 2020; 11:1222. [PMID: 32849756 PMCID: PMC7432134 DOI: 10.3389/fpls.2020.01222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
Plant sexual systems play an important role in the evolution of angiosperm diversity. However, large-scale patterns in the frequencies of sexual systems (i.e. dioecy, monoecy, and hermaphroditism) and their drivers for species with different growth forms remain poorly known. Here, using a newly compiled database on the sexual systems and distributions of 19780 angiosperm species in China, we map the large-scale geographical patterns in frequencies of the sexual systems of woody and herbaceous species separately. We use these data to test the following two hypotheses: (1) the prevalence of sexual systems differs between woody and herbaceous assemblies because woody plants have taller canopies and are found in warm and humid climates; (2) the relative contributions of different drivers (specifically climate, evolutionary age, and mature plant height) to these patterns differ between woody and herbaceous species. We show that geographical patterns in proportions of different sexual systems (especially dioecy) differ between woody and herbaceous species. Geographical variations in sexual systems of woody species were influenced by climate, evolutionary age and plant height. In contrast, these have only weakly significant effects on the patterns of sexual systems of herbaceous species. We suggest that differences between species with woody and herbaceous growth forms in terms of biogeographic patterns of sexual systems, and their drivers, may reflect their differences in physiological and ecological adaptions, as well as the coevolution of sexual system with vegetative traits in response to environmental changes.
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Affiliation(s)
- Yunyun Wang
- National Engineering Laboratory for Applied Technology of Forestry & Ecology in Southern China, and College of Life Science and Technology, Central South University of Forest and Technology, Changsha, China
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Tong Lyu
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, China
| | - Ao Luo
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yaoqi Li
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yunpeng Liu
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Robert P. Freckleton
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
| | - Shuguang Liu
- National Engineering Laboratory for Applied Technology of Forestry & Ecology in Southern China, and College of Life Science and Technology, Central South University of Forest and Technology, Changsha, China
| | - Zhiheng Wang
- Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, China
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45
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Gibson MJS, Crawford DJ, Holder MT, Mort ME, Kerbs B, de Sequeira MM, Kelly JK. Genome-wide genotyping estimates mating system parameters and paternity in the island species Tolpis succulenta. AMERICAN JOURNAL OF BOTANY 2020; 107:1189-1197. [PMID: 32864742 DOI: 10.1002/ajb2.1515] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 02/22/2020] [Indexed: 06/11/2023]
Abstract
PREMISE The mating system has profound consequences, not only for ecology and evolution, but also for the conservation of threatened or endangered species. Unfortunately, small populations are difficult to study owing to limits on sample size and genetic marker diversity. Here, we estimated mating system parameters in three small populations of an island plant using genomic genotyping. Although self-incompatible (SI) species are known to often set some self-seed, little is known about how "leaky SI" affects selfing rates in nature or the role that multiple paternity plays in small populations. METHODS We generalized the BORICE mating system program to determine the siring pattern within maternal families. We applied this algorithm to maternal families from three populations of Tolpis succulenta from Madeira Island and genotyped the progeny using RADseq. We applied BORICE to estimate each individual offspring as outcrossed or selfed, the paternity of each outcrossed offspring, and the level of inbreeding of each maternal plant. RESULTS Despite a functional self-incompatibility system, these data establish T. succulenta as a pseudo-self-compatible (PSC) species. Two of 75 offspring were strongly indicated as products of self-fertilization. Despite selfing, all adult maternal plants were fully outbred. There was high differentiation among and low variation within populations, consistent with a history of genetic isolation of these small populations. There were generally multiple sires per maternal family. Twenty-two percent of sib contrasts (between outcrossed offspring within maternal families) shared the same sire. CONCLUSIONS Genome-wide genotyping, combined with appropriate analytical methods, enables estimation of mating system and multiple paternity in small populations. These data address questions about the evolution of reproductive traits and the conservation of threatened populations.
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Affiliation(s)
- Matthew J S Gibson
- Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS, 66045-7534, USA
| | - Daniel J Crawford
- Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS, 66045-7534, USA
- Biodiversity Institute, University of Kansas, Lawrence, KS, 66045-7534, USA
| | - Mark T Holder
- Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS, 66045-7534, USA
- Biodiversity Institute, University of Kansas, Lawrence, KS, 66045-7534, USA
| | - Mark E Mort
- Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS, 66045-7534, USA
| | - Benjamin Kerbs
- Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS, 66045-7534, USA
| | - Miguel Menezes de Sequeira
- Madeira Botanical Group, Faculty of Life Sciences, University of Madeira, Campus Universitário da Penteada, 9020-105, Funchal, Portugal
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Pólo dos Açores, 9501-81, Ponta Delgada, Portugal
| | - John K Kelly
- Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS, 66045-7534, USA
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Sinclair EA, Edgeloe JM, Anthony JM, Statton J, Breed MF, Kendrick GA. Variation in reproductive effort, genetic diversity and mating systems across Posidonia australis seagrass meadows in Western Australia. AOB PLANTS 2020; 12:plaa038. [PMID: 32904346 PMCID: PMC7454027 DOI: 10.1093/aobpla/plaa038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Populations at the edges of their geographical range tend to have lower genetic diversity, smaller effective population sizes and limited connectivity relative to centre of range populations. Range edge populations are also likely to be better adapted to more extreme conditions for future survival and resilience in warming environments. However, they may also be most at risk of extinction from changing climate. We compare reproductive and genetic data of the temperate seagrass, Posidonia australis on the west coast of Australia. Measures of reproductive effort (flowering and fruit production and seed to ovule ratios) and estimates of genetic diversity and mating patterns (nuclear microsatellite DNA loci) were used to assess sexual reproduction in northern range edge (low latitude, elevated salinities, Shark Bay World Heritage Site) and centre of range (mid-latitude, oceanic salinity, Perth metropolitan waters) meadows in Western Australia. Flower and fruit production were highly variable among meadows and there was no significant relationship between seed to ovule ratio and clonal diversity. However, Shark Bay meadows were two orders of magnitude less fecund than those in Perth metropolitan waters. Shark Bay meadows were characterized by significantly lower levels of genetic diversity and a mixed mating system relative to meadows in Perth metropolitan waters, which had high genetic diversity and a completely outcrossed mating system. The combination of reproductive and genetic data showed overall lower sexual productivity in Shark Bay meadows relative to Perth metropolitan waters. The mixed mating system is likely driven by a combination of local environmental conditions and pollen limitation. These results indicate that seagrass restoration in Shark Bay may benefit from sourcing plant material from multiple reproductive meadows to increase outcrossed pollen availability and seed production for natural recruitment.
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Affiliation(s)
- Elizabeth A Sinclair
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
- Kings Park Science, Department of Biodiversity Conservation and Attractions, West Perth, Western Australia, Australia
| | - Jane M Edgeloe
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Janet M Anthony
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Kings Park Science, Department of Biodiversity Conservation and Attractions, West Perth, Western Australia, Australia
| | - John Statton
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
| | - Martin F Breed
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Gary A Kendrick
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
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Ruane LG, Mangum SM, Horner KM, Moeller DA. The opportunity for outcrossing varies across the geographic range of the primarily selfing Clarkia xantiana ssp. parviflora. AMERICAN JOURNAL OF BOTANY 2020; 107:1198-1207. [PMID: 32700343 DOI: 10.1002/ajb2.1510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 02/22/2020] [Indexed: 06/11/2023]
Abstract
PREMISE The timing of self-fertilization has potentially important consequences for the trajectory of mating system evolution, the opportunity for outcrossing, and the maintenance of genetic variation in populations. For primarily selfing taxa, it remains poorly understood as to how floral variation influences the opportunity for outcrossing and whether those attributes vary among populations across geographic ranges. METHODS We examined variation in floral traits (herkogamy, protandry, flower size, stigma stage at anthesis, timing of stigma receptivity) in seven populations of Clarkia xantiana ssp. parviflora, a primarily selfing taxon, spanning from the western to eastern margins of its distribution. We also performed experimental emasculations and pollinations (followed by stigma severing) to quantify the extent of opportunities for outcrossing across flower development. RESULTS There was marked among-population variation in all floral traits, particularly between far eastern and western populations. Emasculation experiments showed that the eastern populations had minimal autonomous selfing, but western populations had high rates of selfing within 24 h after anthesis. Population variation in autofertility was significantly predicted by floral trait variation, especially protandry and petal size. CONCLUSIONS Greater protandry both extended the time over which outcrossing could potentially occur and reduced the probability of autonomous selfing, suggesting that there may be a tradeoff that results in fitness loss when pollinator visits are not common. The east-west pattern of differentiation in some floral traits parallels that of postglacial range expansion, suggesting that selection on the mating system may have been strong in the process of range expansion.
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Affiliation(s)
- Lauren G Ruane
- Department of Organismal and Environmental Biology, Christopher Newport University, 1 Avenue of the Arts, Newport News, Virginia, 23606, United States
| | - Samantha M Mangum
- Department of Organismal and Environmental Biology, Christopher Newport University, 1 Avenue of the Arts, Newport News, Virginia, 23606, United States
| | - Kaitlyn M Horner
- Department of Organismal and Environmental Biology, Christopher Newport University, 1 Avenue of the Arts, Newport News, Virginia, 23606, United States
| | - David A Moeller
- Department of Plant and Microbial Biology, University of Minnesota, 1479 Gortner Avenue, St. Paul, Minnesota, 55108, United States
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Gillet EM, Gregorius HR. Effects of reproductive resource allocation and pollen density on fertilization success in plants. BMC Ecol 2020; 20:26. [PMID: 32359373 PMCID: PMC7208091 DOI: 10.1186/s12898-020-00290-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 04/11/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Declining resources due to climate change may endanger the persistence of populations by reducing fecundity and thus population fitness via effects on gamete production. The optimal mode of generative reproduction allocates the limited resources to ovule and pollen production in proportions that maximize the number of fertilized ovules in the population. In order to locate this optimum and derive reproduction modes that compensate for declined resources to maintain reproductive success, a model of gamete production, pollen dispersal, and ovule fertilization is developed. Specification of opportunities for compensation is given priority over specification of physiological or evolutionary mechanisms of adaptation. Thus model parameters summarize gametic production resources, resource investment per gamete, resource allocation as proportion of resources invested in ovules, and pollen density as size of the pollen dispersal range and proportion of pollen retained within the range. Retained pollen disperses randomly, and an ovule is fertilized if at least one pollen settles on its surface. The outcome is the expected number of fertilized ovules. RESULTS Maximization of fertilization success is found to require the investment of more gametic production resources in ovules than in pollen, irrespective of the parameter values. Resource decline can be compensated by adjusting the resource allocation if the maximum expected number of fertilized ovules after the decline is not less than the expected number the population experienced before the decline. Compensation is also possible under some conditions by increasing the pollen density, either by raising a low pollen retention or by shrinking the dispersal range. CONCLUSION Fertilization success in populations affected by resource decline may be maintainable by adjustment of the sexual allocation of gametic production resources or by increasing pollen density. The results have implications for insect pollination, sexual allocation bias, management measures, and metapopulation fragmentation.
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Affiliation(s)
- Elizabeth M. Gillet
- Forstgenetik und Forstpflanzenzüchtung. Fakultät Forstwissenschaften und Waldökologie, Universität Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
| | - Hans-Rolf Gregorius
- Forstgenetik und Forstpflanzenzüchtung. Fakultät Forstwissenschaften und Waldökologie, Universität Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
- Institut für ökologische und Populationsgenetik (IPOEG), Am Pfingstanger 58, 37075 Göttingen, Germany
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Hall D, Zhao W, Wennström U, Andersson Gull B, Wang XR. Parentage and relatedness reconstruction in Pinus sylvestris using genotyping-by-sequencing. Heredity (Edinb) 2020; 124:633-646. [PMID: 32123330 PMCID: PMC7171117 DOI: 10.1038/s41437-020-0302-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 02/07/2023] Open
Abstract
Estimating kinship is fundamental for studies of evolution, conservation, and breeding. Genotyping-by-sequencing (GBS) and other restriction based genotyping methods have become widely applied in these applications in non-model organisms. However, sequencing errors, depth, and reproducibility between library preps could potentially hinder accurate genetic inferences. In this study, we tested different sets of parameters in data filtering, different reference populations and eight estimation methods to obtain a robust procedure for relatedness estimation in Scots pine (Pinus sylvestris L.). We used a seed orchard as our study system, where candidate parents are known and pedigree reconstruction can be compared with theoretical expectations. We found that relatedness estimates were lower than expected for all categories of kinship estimated if the proportion of shared SNPs was low. However, estimates reached expected values if loci showing an excess of heterozygotes were removed and genotyping error rates were considered. The genetic variance-covariance matrix (G-matrix) estimation, however, performed poorly in kinship estimation. The reduced relatedness estimates are likely due to false heterozygosity calls. We analyzed the mating structure in the seed orchard and identified a selfing rate of 3% (including crosses between clone mates) and external pollen contamination of 33.6%. Little genetic structure was observed in the sampled Scots pine natural populations, and the degree of inbreeding in the orchard seed crop is comparable to natural stands. We illustrate that under our optimized data processing procedure, relatedness, and genetic composition, including level of pollen contamination within a seed orchard crop, can be established consistently by different estimators.
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Affiliation(s)
- David Hall
- Department of Ecology and Environmental Science, UPSC, Umeå University, Umeå, Sweden
| | - Wei Zhao
- Department of Ecology and Environmental Science, UPSC, Umeå University, Umeå, Sweden.,Advanced Innovation Center for Tree Breeding by Molecular Design; College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | | | | | - Xiao-Ru Wang
- Department of Ecology and Environmental Science, UPSC, Umeå University, Umeå, Sweden.
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Giovanetti M, Giuliani C, Boff S, Fico G, Lupi D. A botanic garden as a tool to combine public perception of nature and life-science investigations on native/exotic plants interactions with local pollinators. PLoS One 2020; 15:e0228965. [PMID: 32078664 PMCID: PMC7032708 DOI: 10.1371/journal.pone.0228965] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 01/27/2020] [Indexed: 11/23/2022] Open
Abstract
Life-sciences are pointing towards an alarming worldwide pollinator decline. This decline proceeds along with overall biodiversity losses, even in the context of urban landscapes and human welfare. At the same time, social-sciences are arguing an increased distance from nature, experienced by citizens. The strong connection between the public good and pollinator sustainability, even in urban areas, is well-documented. However, usually basic and applied life-sciences tend to underestimate public perception of nature, which is better tackled by the fields of social-sciences. Therefore, more efforts are needed to link scientific questions and public ‘perception’ of nature. We designed a transversal project where research questions directly confront public concerns: i.e., even while addressing scientific knowledge gaps, our questions directly arise from public concerns. Social studies highlighted that appreciation of (exotic) plants is related to the impact they may have on the surrounding natural environment: therefore, we investigated links of native and exotic flowers to local pollinators. Other studies highlighted that scientific results need to link to everyday individual experience: therefore, we investigated pollination modes of the renown Salvia, native and exotic, largely used in cuisine and gardening. The botanic garden was the promoter of scientific questions addressed by the public, and also collated the results in a travelling exhibition. The exhibition, together with a dedicated catalogue, were especially designed to enlighten the wide public on the relationships that plants, native and exotic alike, establish with the surrounding world.
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Affiliation(s)
- Manuela Giovanetti
- Centre for Ecology, Evolution and Environmental Changes, University of Lisbon, Lisbon, Portugal
- * E-mail:
| | - Claudia Giuliani
- Department of Pharmaceutical Sciences, University of Milan, Milano, Italy
- Department of Pharmaceutical Sciences, Ghirardi Botanic Garden, University of Milan, Milano, Italy
| | - Samuel Boff
- Department of Food, Environmental and Nutritional Sciences, University of Milan, Milano, Italy
| | - Gelsomina Fico
- Department of Pharmaceutical Sciences, University of Milan, Milano, Italy
- Department of Pharmaceutical Sciences, Ghirardi Botanic Garden, University of Milan, Milano, Italy
| | - Daniela Lupi
- Department of Food, Environmental and Nutritional Sciences, University of Milan, Milano, Italy
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