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Lewis EM, Fant JB, Moore MJ, Skogen KA. Hawkmoth and bee pollinators impact pollen dispersal at the landscape but not local scales in two species of Oenothera. AMERICAN JOURNAL OF BOTANY 2023:e16156. [PMID: 36934437 DOI: 10.1002/ajb2.16156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 02/01/2023] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
PREMISE Animal pollinators play an important role in pollen dispersal. Here, we assessed differences in pollen and seed dispersal and the role of pollinator functional groups with different foraging behaviors in generating patterns of genetic diversity over similar geographic ranges for two closely related taxa. We focused on two members of Oenothera section Calylophus (Onagraceae) that co-occur on gypsum outcrops throughout the northern Chihuahuan Desert but differ in floral phenotype and primary pollinator: Oenothera gayleana (bee) and O. hartwegii subsp. filifolia (hawkmoth). METHODS We measured breeding system and floral traits and studied gene flow and population differentiation at the local (<13 km; four populations) and landscape (60-440 km; five populations) scales using 10-11 nuclear (pollen dispersal) and three plastid (seed dispersal) microsatellite markers. RESULTS Both taxa were self-incompatible and floral traits were consistent with expectations for different pollinators. Seed and pollen dispersal patterns were distinctly different for both species. We found no evidence of genetic structure at the local scale but did at the landscape scale; O. gayleana showed greater differentiation and significant isolation by distance than in O. hartwegii subsp. filifolia. The plastid data were consistent with gravity dispersal of seeds and suggest that pollen dispersal is the principal driver of genetic structure in both species. CONCLUSIONS We demonstrated that pollinator functional groups can impact genetic differentiation in different and predictable ways. Hawkmoths, with larger foraging distances, can maintain gene flow across greater spatial scales than bees.
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Affiliation(s)
- Emily M Lewis
- Northwestern University, Program in Plant Biology and Conservation, Evanston, IL, 60201, USA
| | - Jeremie B Fant
- Northwestern University, Program in Plant Biology and Conservation, Evanston, IL, 60201, USA
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60022, USA
| | - Michael J Moore
- Biology Department, Oberlin College, Oberlin, OH, 44074, USA
| | - Krissa A Skogen
- Northwestern University, Program in Plant Biology and Conservation, Evanston, IL, 60201, USA
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60022, USA
- Department of Biological Sciences, Clemson University, Clemson, SC, 29634, USA
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2
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Skogen KA, Jogesh T, Hilpman ET, Todd SL, Raguso RA. Extensive population-level sampling reveals clinal variation in (R)-(-)-linalool produced by the flowers of an endemic evening primrose, Oenothera harringtonii. PHYTOCHEMISTRY 2022; 200:113185. [PMID: 35436476 DOI: 10.1016/j.phytochem.2022.113185] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 03/31/2022] [Accepted: 04/01/2022] [Indexed: 06/14/2023]
Abstract
The study of floral trait diversity has a long history due to its role in angiosperm diversification. While many studies have focused on visual traits including morphology and color, few have included floral scent despite its importance in pollination. Of the studies that have included floral scent, sampling has been limited and rarely explores variation at the population level. We studied geographic variation in the flowers of Oenothera harringtonii, a rare plant endemic to a vulnerable shortgrass prairie habitat, whose population structure and conservation status are well studied. The self-incompatible flowers of O. harringtonii open at dusk, produce nectar and a strong fragrance, and are pollinated by hawkmoths. We collected floral trait (morphology, scent chemistry and emission rates) data from 650 individuals from 19 wild populations to survey floral variation across the entire range of this species. Similarly, we collected floral data from 49 individuals grown in a greenhouse common garden, to assess whether variation observed in the field is consistent when environment factors (temperature, watering regime, soil) are standardized. We identified 35 floral volatiles representing 5 biosynthetic classes. Population differentiation was stronger for floral scent chemistry than floral morphology. (R)-(-)-linalool was the most important floral trait differentiating populations, exhibiting clinal variation across the distribution of O. harringtonii without any correlated shifts in floral morphology. Populations in the north and west produced (R)-(-)-linalool consistently, those in the east and south largely lacked it, and populations at the center of the distribution were polymorphic. Floral scent emissions in wild populations varied across four years but chemical composition was largely consistent over time. Similarly, volatile emission rates and chemical composition in greenhouse-grown plants were consistent with those of wild populations of origin. Our data set, which represents the most extensive population-level survey of floral scent to date, indicates that such sampling may be needed to capture potentially adaptive geographic variation in wild populations.
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Affiliation(s)
- Krissa A Skogen
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60035, USA.
| | - Tania Jogesh
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60035, USA
| | - Evan T Hilpman
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60035, USA; School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
| | - Sadie L Todd
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60035, USA; Iowa Department of Agriculture and Land Stewardship, Ankeny, IA, 50023, USA
| | - Robert A Raguso
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, 14853, USA
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3
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Bechen LL, Johnson MG, Broadhead GT, Levin RA, Overson RP, Jogesh T, Fant JB, Raguso RA, Skogen KA, Wickett NJ. Differential gene expression associated with a floral scent polymorphism in the evening primrose Oenothera harringtonii (Onagraceae). BMC Genomics 2022; 23:124. [PMID: 35151274 PMCID: PMC8840323 DOI: 10.1186/s12864-022-08370-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 12/30/2021] [Indexed: 12/13/2022] Open
Abstract
Background Plant volatiles play an important role in both plant-pollinator and plant-herbivore interactions. Intraspecific polymorphisms in volatile production are ubiquitous, but studies that explore underlying differential gene expression are rare. Oenothera harringtonii populations are polymorphic in floral emission of the monoterpene (R)-(−)-linalool; some plants emit (R)-(−)-linalool (linalool+ plants) while others do not (linalool- plants). However, the genes associated with differential production of this floral volatile in Oenothera are unknown. We used RNA-Seq to broadly characterize differential gene expression involved in (R)-(−)-linalool biosynthesis. To identify genes that may be associated with the polymorphism for this trait, we used RNA-Seq to compare gene expression in six different Oenothera harringtonii tissues from each of three linalool+ and linalool- plants. Results Three clusters of differentially expressed genes were enriched for terpene synthase activity: two were characterized by tissue-specific upregulation and one by upregulation only in plants with flowers that produce (R)-(−)-linalool. A molecular phylogeny of all terpene synthases identified two putative (R)-(−)-linalool synthase transcripts in Oenothera harringtonii, a single allele of which is found exclusively in linalool+ plants. Conclusions By using a naturally occurring polymorphism and comparing different tissues, we were able to identify candidate genes putatively involved in the biosynthesis of (R)-(−)-linalool. Expression of these genes in linalool- plants, while low, suggests a regulatory polymorphism, rather than a population-specific loss-of-function allele. Additional terpene biosynthesis-related genes that are up-regulated in plants that emit (R)-(−)-linalool may be associated with herbivore defense, suggesting a potential economy of scale between plant reproduction and defense. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08370-6.
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4
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Emel SL, Wang S, Metz RP, Spigler RB. Type and intensity of surrounding human land use, not local environment, shape genetic structure of a native grassland plant. Mol Ecol 2021; 30:639-655. [PMID: 33245827 DOI: 10.1111/mec.15753] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 11/01/2020] [Accepted: 11/13/2020] [Indexed: 12/28/2022]
Abstract
Landscape heterogeneity can shape genetic structure and functional connectivity of populations. When this heterogeneity imposes variable costs of moving across the landscape, populations can be structured according to a pattern of "isolation by resistance" (IBR). At the same time, divergent local environmental filters can limit gene flow, creating an alternative pattern of "isolation by environment" (IBE). Here, we evaluate IBR and IBE in the insect-pollinated, biennial plant Sabatia angularis (L.) Pursh (Gentianaceae) across serpentine grasslands in the fragmented landscape of SE Pennsylvania, USA using ~4500 neutral SNP loci. Specifically, we test the extent to which radical alteration of the landscape matrix by humans has fundamentally altered the cost of movement, imprinting a pattern of IBR dictated by land use type and intensity, and the potential for IBE in relation to a gradient of heavy metal concentrations found in serpentine soil. We reveal a strong signal of IBR and a weak signal of IBE across sites, indicating the greater importance of the landscape matrix in shaping genetic structure of S. angularis populations in the study region. Based on Circuitscape and least cost path approaches, we find that both low- and high-intensity urbanization resist gene flow by orders of magnitude greater than "natural" habitats, although resistance to low-intensity urbanization weakens at larger spatial scales. While cropland presents a substantially lower barrier than urban development, cumulative human land use surrounding populations predicts within-population genetic diversity and inbreeding in S. angularis. Our results emphasize the role of forest buffers and corridors in facilitating gene flow between serpentine grassland patches and averting local extinction of plant populations.
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Affiliation(s)
- Sarah L Emel
- Department of Biology, Temple University, Philadelphia, PA, USA.,Department of Biology, Indiana University of Pennsylvania, Indiana, PA, USA
| | - Shichen Wang
- Genomics and Bioinformatics Service, Texas A&M AgriLife Research, TX, USA
| | - Richard P Metz
- Genomics and Bioinformatics Service, Texas A&M AgriLife Research, TX, USA
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5
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Affiliation(s)
| | - Anne Halford
- Idaho State Office Division of Resources and ScienceUSDI Bureau of Land Management Boise ID U.S.A
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6
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Zhou J, Dudash MR, Zimmer EA, Fenster CB. Comparison of population genetic structures of the plant Silene stellata and its obligate pollinating seed predator moth Hadena ectypa. ANNALS OF BOTANY 2018; 122:593-603. [PMID: 29850821 PMCID: PMC6153480 DOI: 10.1093/aob/mcy091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 05/03/2018] [Indexed: 05/29/2023]
Abstract
BACKGROUND AND AIMS Population genetic structures and patterns of gene flow of interacting species provide important insights into the spatial scale of their interactions and the potential for local co-adaptation. We analysed the genetic structures of the plant Silene stellata and the nocturnal moth Hadena ectypa. Hadena ectypa acts as one of the important pollinators of S. stellata as well as being an obligate seed parasite on the plant. Although H. ectypa provides a substantial pollination service to S. stellata, this system is largely considered parasitic due to the severe seed predation by the Hadena larvae. Previous research on this system has found variable interaction outcomes across space, indicating the potential for a geographical selection mosaic. METHODS Using 11 microsatellite markers for S. stellata and nine markers for H. ectypa, we analysed the population genetic structure and the patterns and intensity of gene flow within and among three local populations in the Appalachians. KEY RESULTS We found no spatial genetic structure in the moth populations, while significant differentiation was detected among the local plant populations. Additionally, we observed that gene flow rates among H. ectypa populations were more uniform and that the mean gene flow rate in H. ectypa was twice as large as that in S. stellata. CONCLUSIONS Our results suggest that although the moths move frequently among populations, long-distance pollen carryover only happens occasionally. The difference in gene flow rates between S. stellata and H. ectypa could prevent strict local co-adaptation. Furthermore, higher gene flow rates in H. ectypa could also increase resistance of the local S. stellata populations to the parasitic effect of H. ectypa and therefore help to stabilize the Silene-Hadena interaction dynamics.
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Affiliation(s)
- Juannan Zhou
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Michele R Dudash
- Department of Natural Resource Management, South Dakota State University, Brookings, SD, USA
| | - Elizabeth A Zimmer
- Department of Botany, National Museum of Natural History, MRC 166, Smithsonian Institution, Washington, DC, USA
| | - Charles B Fenster
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD, USA
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Smith JR, Ghazoul J, Burslem DFRP, Itoh A, Khoo E, Lee SL, Maycock CR, Nanami S, Ng KKS, Kettle CJ. Are patterns of fine-scale spatial genetic structure consistent between sites within tropical tree species? PLoS One 2018; 13:e0193501. [PMID: 29547644 PMCID: PMC5856272 DOI: 10.1371/journal.pone.0193501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 02/12/2018] [Indexed: 11/18/2022] Open
Abstract
Documenting the scale and intensity of fine-scale spatial genetic structure (FSGS), and the processes that shape it, is relevant to the sustainable management of genetic resources in timber tree species, particularly where logging or fragmentation might disrupt gene flow. In this study we assessed patterns of FSGS in three species of Dipterocarpaceae (Parashorea tomentella, Shorea leprosula and Shorea parvifolia) across four different tropical rain forests in Malaysia using nuclear microsatellite markers. Topographic heterogeneity varied across the sites. We hypothesised that forests with high topographic heterogeneity would display increased FSGS among the adult populations driven by habitat associations. This hypothesis was not supported for S. leprosula and S. parvifolia which displayed little variation in the intensity and scale of FSGS between sites despite substantial variation in topographic heterogeneity. Conversely, the intensity of FSGS for P. tomentella was greater at a more topographically heterogeneous than a homogeneous site, and a significant difference in the overall pattern of FSGS was detected between sites for this species. These results suggest that local patterns of FSGS may in some species be shaped by habitat heterogeneity in addition to limited gene flow by pollen and seed dispersal. Site factors can therefore contribute to the development of FSGS. Confirming consistency in species’ FSGS amongst sites is an important step in managing timber tree genetic diversity as it provides confidence that species specific management recommendations based on species reproductive traits can be applied across a species’ range. Forest managers should take into account the interaction between reproductive traits and site characteristics, its consequences for maintaining forest genetic resources and how this might influence natural regeneration across species if management is to be sustainable.
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Affiliation(s)
- James R. Smith
- Institute for Terrestrial Ecology, ETH Zurich, Zurich, Switzerland
| | - Jaboury Ghazoul
- Institute for Terrestrial Ecology, ETH Zurich, Zurich, Switzerland
| | | | - Akira Itoh
- Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, Japan
| | - Eyen Khoo
- Forest Research Centre, Sabah Forestry Department, Sabah, Malaysia
| | - Soon Leong Lee
- Forest Research Institute Malaysia, Kepong, Selangor, Malaysia
| | - Colin R. Maycock
- Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Sabah, Malaysia
| | - Satoshi Nanami
- Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, Japan
| | | | - Chris J. Kettle
- Institute for Terrestrial Ecology, ETH Zurich, Zurich, Switzerland
- * E-mail:
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8
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Torroba-Balmori P, Budde KB, Heer K, González-Martínez SC, Olsson S, Scotti-Saintagne C, Casalis M, Sonké B, Dick CW, Heuertz M. Altitudinal gradients, biogeographic history and microhabitat adaptation affect fine-scale spatial genetic structure in African and Neotropical populations of an ancient tropical tree species. PLoS One 2017; 12:e0182515. [PMID: 28771629 PMCID: PMC5542443 DOI: 10.1371/journal.pone.0182515] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 07/08/2017] [Indexed: 01/08/2023] Open
Abstract
The analysis of fine-scale spatial genetic structure (FSGS) within populations can provide insights into eco-evolutionary processes. Restricted dispersal and locally occurring genetic drift are the primary causes for FSGS at equilibrium, as described in the isolation by distance (IBD) model. Beyond IBD expectations, spatial, environmental or historical factors can affect FSGS. We examined FSGS in seven African and Neotropical populations of the late-successional rain forest tree Symphonia globulifera L. f. (Clusiaceae) to discriminate the influence of drift-dispersal vs. landscape/ecological features and historical processes on FSGS. We used spatial principal component analysis and Bayesian clustering to assess spatial genetic heterogeneity at SSRs and examined its association with plastid DNA and habitat features. African populations (from Cameroon and São Tomé) displayed a stronger FSGS than Neotropical populations at both marker types (mean Sp = 0.025 vs. Sp = 0.008 at SSRs) and had a stronger spatial genetic heterogeneity. All three African populations occurred in pronounced altitudinal gradients, possibly restricting animal-mediated seed dispersal. Cyto-nuclear disequilibria in Cameroonian populations also suggested a legacy of biogeographic history to explain these genetic patterns. Conversely, Neotropical populations exhibited a weaker FSGS, which may reflect more efficient wide-ranging seed dispersal by Neotropical bats and other dispersers. The population from French Guiana displayed an association of plastid haplotypes with two morphotypes characterized by differential habitat preferences. Our results highlight the importance of the microenvironment for eco-evolutionary processes within persistent tropical tree populations.
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Affiliation(s)
- Paloma Torroba-Balmori
- Department of Forest Ecology and Genetics, INIA Forest Research Centre, Madrid, Spain
- Sustainable Forest Management Research Institute, University of Valladolid - INIA, Palencia, Spain
| | | | - Katrin Heer
- Institute of Experimental Ecology, University of Ulm, Ulm, Germany
- Conservation Biology and Ecology, University of Marburg, Marburg, Germany
| | - Santiago C. González-Martínez
- Department of Forest Ecology and Genetics, INIA Forest Research Centre, Madrid, Spain
- Sustainable Forest Management Research Institute, University of Valladolid - INIA, Palencia, Spain
- UMR BIOGECO, INRA, University of Bordeaux, Cestas, France
| | - Sanna Olsson
- Department of Forest Ecology and Genetics, INIA Forest Research Centre, Madrid, Spain
| | | | | | - Bonaventure Sonké
- Ecole Normale Supérieure, Université de Yaoundé I, Yaoundé, Cameroon
- Evolutionary Biology and Ecology, Faculté des Sciences, Université Libre de Bruxelles, Brussels, Belgium
| | - Christopher W. Dick
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, United States of America
- Smithsonian Tropical Research Institute, Republic of Panama
| | - Myriam Heuertz
- Department of Forest Ecology and Genetics, INIA Forest Research Centre, Madrid, Spain
- UMR BIOGECO, INRA, University of Bordeaux, Cestas, France
- Evolutionary Biology and Ecology, Faculté des Sciences, Université Libre de Bruxelles, Brussels, Belgium
- * E-mail:
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9
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Rhodes MK, Fant JB, Skogen KA. Pollinator identity and spatial isolation influence multiple paternity in an annual plant. Mol Ecol 2017; 26:4296-4308. [PMID: 28334485 DOI: 10.1111/mec.14115] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/27/2017] [Accepted: 03/01/2017] [Indexed: 11/27/2022]
Abstract
The occurrence and extent of multiple paternity is an important component of variation in plant mating dynamics. However, links between pollinator activity and multiple paternity are generally lacking, especially for plant species that attract functionally diverse floral visitors. In this study, we separated the influence of two functionally distinct floral visitors (hawkmoths and solitary bees) and characterized their impacts on multiple paternity in a self-incompatible, annual forb, Oenothera harringtonii (Onagraceae). We also situated pollinator-mediated effects in a spatial context by linking variation in multiple paternity to variation in plant spatial isolation. We documented pronounced differences in the number of paternal sires as function of pollinator identity: on average, the primary pollinator (hawkmoths) facilitated mating with nearly twice as many pollen donors relative to the secondary pollinator (solitary bees). This effect was consistent for both isolated and nonisolated individuals, but spatial isolation imposed pronounced reductions on multiple paternity regardless of pollinator identity. Considering that pollinator abundance and pollen dispersal distance did not vary significantly with pollinator identity, we attribute variation in realized mating dynamics primarily to differences in pollinator morphology and behaviour as opposed to pollinator abundance or mating incompatibility arising from underlying spatial genetic structure. Our findings demonstrate that functionally distinct pollinators can have strongly divergent effects on polyandry in plants and further suggest that both pollinator identity and spatial heterogeneity have important roles in plant mating dynamics.
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Affiliation(s)
- Matthew K Rhodes
- Division of Plant Science and Conservation, Chicago Botanic Garden, 1000 Lake Cook Rd, Glencoe, IL, 60022, USA.,Program in Plant Biology and Conservation, Northwestern University, 2205 Tech Drive, O.T. Hogan Hall, Room 2-144, Evanston, IL, 60208, USA
| | - Jeremie B Fant
- Division of Plant Science and Conservation, Chicago Botanic Garden, 1000 Lake Cook Rd, Glencoe, IL, 60022, USA
| | - Krissa A Skogen
- Division of Plant Science and Conservation, Chicago Botanic Garden, 1000 Lake Cook Rd, Glencoe, IL, 60022, USA
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10
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Inter-annual maintenance of the fine-scale genetic structure in a biennial plant. Sci Rep 2016; 6:37712. [PMID: 27883087 PMCID: PMC5121606 DOI: 10.1038/srep37712] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 11/02/2016] [Indexed: 11/13/2022] Open
Abstract
Within plant populations, space-restricted gene movement, together with environmental heterogeneity, can result in a spatial variation in gene frequencies. In biennial plants, inter-annual flowering migrants can homogenize gene frequencies between consecutive cohorts. However, the actual impact of these migrants on spatial genetic variation remains unexplored. Here, we used 10 nuclear microsatellite and one plastid genetic marker to characterize the spatial genetic structure within two consecutive cohorts in a population of the biennial plant Erysimum mediohispanicum (Brassicaceae). We explored the maintenance of this structure between consecutive flowering cohorts at different levels of complexity, and investigated landscape effects on gene flow. We found that cohorts were not genetically differentiated and showed a spatial genetic structure defined by a negative genetic-spatial correlation at fine scale that varied in intensity with compass directions. This spatial genetic structure was maintained when comparing plants from different cohorts. Additionally, genotypes were consistently associated with environmental factors such as light availability and soil composition, but to a lesser extent compared with the spatial autocorrelation. We conclude that inter-annual migrants, in combination with limited seed dispersal and environmental heterogeneity, play a major role in shaping and maintaining the spatial genetic structure among cohorts in this biennial plant.
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Skogen KA, Jogesh T, Hilpman ET, Todd SL, Rhodes MK, Still SM, Fant JB. Land-use change has no detectable effect on reproduction of a disturbance-adapted, hawkmoth-pollinated plant species. AMERICAN JOURNAL OF BOTANY 2016; 103:1950-1963. [PMID: 27803000 DOI: 10.3732/ajb.1600302] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 09/22/2016] [Indexed: 06/06/2023]
Abstract
PREMISE OF THE STUDY Land-use change is cited as a primary driver of global biodiversity loss, with myriad consequences for species, populations, and ecosystems. However, few studies have examined its impact on species interactions, particularly pollination. Furthermore, when the effects of land-use change on pollination have been studied, the focus has largely been on species pollinated by diurnal pollinators, namely, bees and butterflies. Here, we focus on Oenothera harringtonii, a night-flowering, disturbance-adapted species that has experienced a range-wide gradient of land-use change. We tested the hypothesis that the negative impacts of land-use change are mitigated by long-distance pollination. METHODS Our study included both temporal (4 yr) and spatial (19 populations range-wide, and 1, 2, and 5 km from the population center) data, providing a comprehensive understanding of the role of land-use change on pollination biology and reproduction. KEY RESULTS We first confirmed that O. harringtonii is self-incompatible and reliant on pollinators for reproduction. We then showed that hawkmoths (primarily Hyles lineata) are highly reliable and effective pollinators in both space and time. Unlike other studies, we did not detect an effect of population size, increased isolation, or a reduction in suitable habitat in areas with evidence of land-use change on pollination (visitation, pollen removal and deposition). Furthermore, the proportion of suitable habitat and other fragmentation metrics examined were not associated with population size or density in this plant species. CONCLUSIONS We conclude that nocturnal pollination of Oenothera harringtonii via hawkmoths is robust to the negative impacts of land-use change.
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Affiliation(s)
- Krissa A Skogen
- Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
| | - Tania Jogesh
- Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
| | - Evan T Hilpman
- Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
- Washingtion State University, School of Biological Sciences, P.O. Box 644236, Pullman, Washington 99164 USA
| | - Sadie L Todd
- Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
- Iowa Department of Agriculture and Land Stewardship, 2230 S. Ankeny Boulevard, Ankeny, Iowa 50023 USA
| | - Matthew K Rhodes
- Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
- Department of Ecology and Evolutionary Biology, University of Arizona, P.O. Box 210088, Tucson, Arizona 85721 USA
| | - Shannon M Still
- Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
- University of California Davis Arboretum and Public Garden, One Shields Avenue, Davis, California 95616 USA
| | - Jeremie B Fant
- Chicago Botanic Garden 1000 Lake Cook Road, Glencoe, Illinois 60022 USA
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