1
|
Nishida S, Takano A, Suyama Y, Kakishima S. Detection of reproductive interference between closely related Salvia species with small-scale separated distributions by multifaceted pollination and molecular analyses. JOURNAL OF PLANT RESEARCH 2024:10.1007/s10265-024-01577-6. [PMID: 39214907 DOI: 10.1007/s10265-024-01577-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 08/22/2024] [Indexed: 09/04/2024]
Abstract
Reproductive interference, an interspecific interaction in reproductive process that exerts an adverse effect, has gained attention as a contributing factor in promoting exclusive distributions between closely related species. However, detailed studies on the possibility of reproductive interference between native plants are still lacking, presumably because strong reproductive interference can rapidly realize exclusive distributions, leaving the two species apparently independent. Salvia japonica and S. lutescens are found in separate localities at a small scale, although their distributions overlap at a large scale. We investigated the possibility of reproductive interference between them through field surveys, hand-pollination experiments, evaluation of hybrid fertility, cpDNA and nrDNA genotyping, and genome-wide DNA analysis. The field survey results did not reveal apparent negative interaction in competition for pollinator services. Mixed pollination with conspecific pollen and counterpart pollen reduced seed set in S. japonica, and hybrid progeny produced by mixed pollination were less than 20% as fertile compared to the pure species. The DNA genotyping results suggested the possibility of hybridization where their distributions overlap, and the genome-wide DNA analysis results showed clear genetic differentiation between the two species as well as the existence of hybrids. These results suggest that bi-directional reproductive interference between S. japonica and S. lutescens may have led to their present separated distributions at a small scale.
Collapse
Affiliation(s)
- Sachiko Nishida
- Nagoya University Museum, Furo-Cho, Chikusa-Ku, Nagoya, 464-8601, Japan.
| | - Atsuko Takano
- University of Hyogo/ Museum of Nature and Human Activities, Yayoigaoka 6, Sanda, Hyogo, 669-1546, Japan
| | - Yoshihisa Suyama
- Kawatabi Field Science Center, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-Onsen, Osaki, Miyagi, 989-6711, Japan
| | - Satoshi Kakishima
- Department of Botany, National Museum of Nature and Science, 4-1-1, Amakubo, Tsukuba-Shi, Ibaraki, 305-0005, Japan
- The Mt. Fuji Institute for Nature and Biology, Showa University, 4562 Kamiyoshida, Fujiyoshida, Yamanashi, 403-0005, Japan
| |
Collapse
|
2
|
Wu Y, Linan AG, Hoban S, Hipp AL, Ricklefs RE. Divergent ecological selection maintains species boundaries despite gene flow in a rare endemic tree, Quercus acerifolia (maple-leaf oak). J Hered 2024; 115:575-587. [PMID: 38881254 DOI: 10.1093/jhered/esae033] [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: 10/06/2023] [Accepted: 06/11/2024] [Indexed: 06/18/2024] Open
Abstract
Strong gene flow from outcrossing relatives tends to blur species boundaries, while divergent ecological selection can counteract gene flow. To better understand how these two forces affect the maintenance of species boundaries, we focused on a species complex including a rare species, maple-leaf oak (Quercus acerifolia), which is found in only four disjunct ridges in Arkansas. Its limited range and geographic proximity to co-occurring close relatives create the possibility for genetic swamping. In this study, we gathered genome-wide single nucleotide polymorphisms (SNPs) using restriction-site-associated DNA sequencing (RADseq) from 190 samples of Q. acerifolia and three of its close relatives, Q. shumardii, Q. buckleyi, and Q. rubra. We found that Q. shumardii and Q. acerifolia are reciprocally monophyletic with low support, suggesting incomplete lineage sorting, introgression between Q. shumardii and Q. acerifolia, or both. Analyses that model allele distributions demonstrate that admixture contributes strongly to this pattern. Populations of Q. acerifolia experience gene flow from Q. shumardii and Q. rubra, but we found evidence that divergent selection is likely maintaining species boundaries: 1) ex situ collections of Q. acerifolia have a higher proportion of hybrids compared to the mature trees of the wild populations, suggesting ecological selection against hybrids at the seed/seedling stage; 2) ecological traits co-vary with genomic composition; and 3) Q. acerifolia shows genetic differentiation at loci hypothesized to influence tolerance of radiation, drought, and high temperature. Our findings strongly suggest that in maple-leaf oak, selection results in higher divergence at regions of the genome despite gene flow from close relatives.
Collapse
Affiliation(s)
- Yingtong Wu
- Biology Department, University of Missouri-St. Louis, St. Louis, MO, United States
- Whitney R. Harris World Ecology Center, University of Missouri-St. Louis, St. Louis, MO, United States
| | - Alexander G Linan
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St. Louis, MO, United States
| | - Sean Hoban
- Center for Tree Science, The Morton Arboretum, Lisle, IL, United States
| | - Andrew L Hipp
- Center for Tree Science, The Morton Arboretum, Lisle, IL, United States
- The Field Museum, Integrative Research Center, Chicago, IL, United States
| | - Robert E Ricklefs
- Biology Department, University of Missouri-St. Louis, St. Louis, MO, United States
| |
Collapse
|
3
|
Wang M, Zhu M, Qian J, Yang Z, Shang F, Egan AN, Li P, Liu L. Phylogenomics of mulberries (Morus, Moraceae) inferred from plastomes and single copy nuclear genes. Mol Phylogenet Evol 2024; 197:108093. [PMID: 38740145 DOI: 10.1016/j.ympev.2024.108093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 04/30/2024] [Accepted: 05/06/2024] [Indexed: 05/16/2024]
Abstract
Mulberries (genus Morus), belonging to the order Rosales, family Moraceae, are important woody plants due to their economic values in sericulture, as well as for nutritional benefits and medicinal values. However, the taxonomy and phylogeny of Morus, especially for the Asian species, remains challenging due to its wide geographical distribution, morphological plasticity, and interspecific hybridization. To better understand the evolutionary history of Morus, we combined plastomes and a large-scale nuclear gene analyses to investigate their phylogenetic relationships. We assembled the plastomes and screened 211 single-copy nuclear genes from 13 Morus species and related taxa. The plastomes of Morus species were relatively conserved in terms of genome size, gene content, synteny, IR boundary and codon usage. Using nuclear data, our results elucidated identical topologies based on coalescent and concatenation methods. The genus Morus was supported as monophyletic, with M. notabilis as the first diverging lineage and the two North American Morus species, M. microphylla and M. rubra, as sister to the other Asian species. In the Asian Morus species, interspecific relationships were completely resolved. However, cyto-nuclear discordances and gene tree-species tree conflicts were detected in the phylogenies of Morus, with multiple evidences supporting hybridization/introgression as the main cause of discordances between nuclear and plastid phylogenies, while gene tree-species tree conflicts were mainly caused by ILS.
Collapse
Affiliation(s)
- Meizhen Wang
- College of Life Sciences, Henan Normal University, Xinxiang 453000, China; Systematic & Evolutionary Botany and Biodiversity Group, MOE Key Laboratory of Biosystems Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Mengmeng Zhu
- Laboratory of Plant Germplasm and Genetic Engineering, School of Life Sciences, Henan University, Kaifeng 475001, China
| | - Jiayi Qian
- College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China
| | - Zhaoping Yang
- College of Life Sciences and Technologies, Tarim University, Alar 843300, China
| | - Fude Shang
- Laboratory of Plant Germplasm and Genetic Engineering, School of Life Sciences, Henan University, Kaifeng 475001, China; College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China.
| | - Ashley N Egan
- Department of Biology, Utah Valley University, Orem, UT 84058, United States.
| | - Pan Li
- Systematic & Evolutionary Botany and Biodiversity Group, MOE Key Laboratory of Biosystems Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Luxian Liu
- College of Life Sciences, Henan Normal University, Xinxiang 453000, China; Laboratory of Plant Germplasm and Genetic Engineering, School of Life Sciences, Henan University, Kaifeng 475001, China.
| |
Collapse
|
4
|
Nishida S, Tamakoshi N, Takakura KI, Watanabe Y, Kanaoka MM. Reproductive interference between alien species in Veronica. JOURNAL OF PLANT RESEARCH 2024; 137:167-178. [PMID: 38108991 DOI: 10.1007/s10265-023-01510-3] [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: 06/02/2023] [Accepted: 11/17/2023] [Indexed: 12/19/2023]
Abstract
Reproductive interference can lead to the exclusive distribution of species. Reports on reproductive interference between alien species are scarce, although alien species are becoming more abundant and evaluations of the interference between aliens and its influence on community structure are essential. We therefore investigated the presence of interference in two alien species of Veronica, V. cymbalaria and V. persica. Hand-pollination experiments revealed that heterospecific pollen adversely affected both species, but asymmetrically: in V. cymbalaria, it reduced the number of seeds both before and after conspecific pollination, but in V. persica it reduced the number of seeds only when it occurred before conspecific pollination. Field observation suggested that the number of seeds produced by V. cymbalaria was more influenced by the number of conspecific flowers than by the frequency of surrounding V. persica flowers. Pot experiments did not show a negative effect of heterospecific individuals on the reproductive success of focal species in either species. Observations of visiting pollinators revealed no pollinator preference between the plant species. Although we demonstrated asymmetrical reproductive interference between V. cymbalaria and V. persica, its effect in the field seemed limited. An essential factor mitigating the adverse effect of reproductive interference might be a shortage of pollinators that could facilitate interspecific pollination. We predict that further invasion of V. cymbalaria into areas where V. persica prevails is unlikely, although swift displacement of V. cymbalaria by V. persica in areas where V. cymbalaria is already established is also unlikely.
Collapse
Affiliation(s)
- Sachiko Nishida
- Graduate School of Environmental Studies, Nagoya University, Furo‑cho, Chikusa‑ku, Nagoya, 464‑8601, Japan.
- Nagoya University Museum, Furo‑cho, Chikusa‑ku, Nagoya, 464‑8601, Japan.
| | - Naoko Tamakoshi
- Graduate School of Environmental Studies, Nagoya University, Furo‑cho, Chikusa‑ku, Nagoya, 464‑8601, Japan
| | - Ko-Ichi Takakura
- School of Environmental Science, The University of Shiga Prefecture, Yasaka‑cho, Hikone, 552‑0057, Japan
| | - Yuta Watanabe
- Graduate School of Environmental Studies, Nagoya University, Furo‑cho, Chikusa‑ku, Nagoya, 464‑8601, Japan
| | - Masahiro M Kanaoka
- Graduate School of Science, Nagoya University, Furo‑cho, Chikusa‑ku, Nagoya, 464‑8601, Japan
- Faculty of Bioresource Sciences, Prefectural University of Hiroshima, Nanatsuka-Cho, Shobara, 727-0023, Japan
| |
Collapse
|
5
|
Greaves E, Kron P, Husband BC. Demographic and reproductive impacts of hybridization unrelated to hybrid viability in a native plant. AMERICAN JOURNAL OF BOTANY 2023; 110:e16208. [PMID: 37409880 DOI: 10.1002/ajb2.16208] [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: 12/15/2022] [Revised: 04/28/2023] [Accepted: 05/03/2023] [Indexed: 07/07/2023]
Abstract
PREMISE Introduced species can influence native congeners through production of hybrids and introgression, but impacts not involving viable hybrids, such as reduced conspecific offspring and increased asexual seed production, are rarely examined. Here we tested for these demographic and reproductive consequences of hybridization between introduced, domesticated apple (Malus domestica) and native crabapple (M. coronaria) in southern Canada. METHODS We applied four pollination treatments (open, M. coronaria, M. domestica, open + M. coronaria) to focal M. coronaria trees across multiple years and assessed the number and reproductive origins of resulting seeds (hybrid or conspecific endosperm and, for each, sexual or asexual embryo) using flow cytometry. RESULTS In open-pollinated fruit, 27% of seeds had hybrid endosperm; 52% of embryos were asexual. The number of conspecific embryos (sexual or asexual) per fruit did not decline significantly with increasing hybridization, indicating no seed discounting, but hand pollinations using only domestic apple or crabapple pollen reduced the number of conspecific embryos significantly. Hybridization was not associated with a change in percentage asexual embryos, overall, but there was an increase in asexual embryos in tetraploid seeds, the maternal and most common offspring ploidy. CONCLUSIONS We conclude that hybridization can influence native Malus in ways beyond the production of viable hybrids, with significant implications for population dynamics and genetic structure.
Collapse
Affiliation(s)
- Elaina Greaves
- Department of Integrative Biology, University of Guelph, 50 Stone Road E., Guelph, Ontario, N1G 2W1, Canada
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, 50 Stone Road E., Guelph, Ontario, N1G 2W1, Canada
| | - Brian C Husband
- Department of Integrative Biology, University of Guelph, 50 Stone Road E., Guelph, Ontario, N1G 2W1, Canada
| |
Collapse
|
6
|
Zou TT, Lyu ST, Jiang QL, Shang SH, Wang XF. Pre- and post-pollination barriers between two exotic and five native Sagittaria species: Implications for species conservation. PLANT DIVERSITY 2023; 45:456-468. [PMID: 37601545 PMCID: PMC10435913 DOI: 10.1016/j.pld.2022.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 10/04/2022] [Accepted: 10/10/2022] [Indexed: 08/22/2023]
Abstract
Anthropogenic introduction of species has resulted in a breakdown of geographical barriers and hybridization in previously allopatric species. Thus, examining hybridization proneness of exotic species contributes to revealing its potential threat. Moreover, reproductive barriers may be strengthened or weakened due to long-term geographical isolation for these newly sympatric species. However, few studies have evaluated multiple barriers between alien and native species. In this study, we quantified the importance of four pre-pollination barriers (phenological, floral traits, pollen production, and floral constancy) and four post-pollination barriers (pollen-pistil incompatibility, seed set, seed viability, and seedling survival) between two introduced and five native Sagittaria species. Results showed that introduced S. platyphylla was cross-compatible with two native species, whereas introduced S. montevidensis was incapable of hybridizing with any native species. Different barriers were asymmetric within species pairs and multiple barriers acted in concert to maintain species boundaries. Post-pollination barriers contributed more to total reproductive isolation in native species, whereas pre-pollination barriers played a stronger role in total reproductive isolation for two introduced species. Seed set was the only barrier that was positively correlated with genetic distance. Our results provide a perspective to better understand reproductive barriers for secondary contact species. We highlight the importance of monitoring hybridization events before human introduction and the possible conservation strategies to remove invasive species with hybridization proneness.
Collapse
Affiliation(s)
- Ting-Ting Zou
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Sen-Tao Lyu
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Qi-Lin Jiang
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Shu-He Shang
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Xiao-Fan Wang
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| |
Collapse
|
7
|
Fang Q, Zhang T, Montgomery BR. Spatial variation of pollen receipt and effects of heterospecific pollen on seed set in Salvia przewalskii. Ecol Evol 2023; 13:e9795. [PMID: 36760706 PMCID: PMC9897956 DOI: 10.1002/ece3.9795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 01/06/2023] [Accepted: 01/18/2023] [Indexed: 02/05/2023] Open
Abstract
Generalized pollinators visit multiple co-flowering plant species and may transfer heterospecific pollen grains. Recent studies have indicated that the effect of heterospecific pollen (HP) on reproduction success is variable and depends on the identity of donor and recipient species. However, few studies have documented variation in HP receipt and evaluated the reproductive effects of HP receipt across geographic locations under natural conditions. We investigated the spatial variation of pollen deposition across eight sites and how the pollen receipt related to the seed set of Salvia przewalskii, a subalpine perennial herb in Hengduan Mountain in southwest China. We found that stigmatic pollen loads substantially varied among sites for several metrics, including quantities of conspecific and heterospecific pollen, the proportion of HP, and species composition of HP donors. Five different plant families were the most common HP source at one or two sites, and the proportion of HP ranged from 3.4% to 51.3% across sites. The association of conspecific pollen with seed set was positive and variable among sites, whereas the association of HP receipt and seed set was negative and not significantly different among sites. Our results demonstrate variation in the quantity and fitness effect of pollen receipt across sites, which is a precondition for evolution of local adaptation. Further study of variation in patterns and effects of HP receipt for the same recipient species across natural communities would allow better understanding of the ecological and evolutionary consequences of HP receipt.
Collapse
Affiliation(s)
- Qiang Fang
- College of AgricultureHenan University of Science and TechnologyLuoyangChina
| | - Tao Zhang
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of BiodiversitySchool of Ecology and Environmental Science, Yunnan UniversityKunmingChina
| | | |
Collapse
|
8
|
Zeng Q, Chen M, Wang S, Xu X, Li T, Xiang Z, He N. Comparative and phylogenetic analyses of the chloroplast genome reveal the taxonomy of the Morus genus. FRONTIERS IN PLANT SCIENCE 2022; 13:1047592. [PMID: 36507423 PMCID: PMC9729782 DOI: 10.3389/fpls.2022.1047592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 10/24/2022] [Indexed: 06/17/2023]
Abstract
Mulberry (genus Morus) is an economically important woody plant with an altered ploidy level. The variable number of Morus species recognized by different studies indicates that the genus is in need of revision. In this study, the chloroplast (CP) genomes of 123 Morus varieties were de novo assembled and systematically analyzed. The 123 varieties represented six Morus species, namely, Morus alba, Morus nigra, Morus notabilis, Morus rubra, Morus celtidifolia, and Morus serrata. The Morus CP genome was found to be 158,969~159,548 bp in size with 125 genes, including 81 protein coding, 36 tRNA, and 8 rRNA genes. The 87 out of 123 mulberry accessions were assigned to 14 diverse groups with identical CP genome, which indicated that they are maternally inherited and share 14 common ancestors. Then 50 diverse CP genomes occurred in 123 mulberry accessions for further study. The CP genomes of the Morus genus with a quadripartite structure have two inverted repeat (IR) regions (25,654~25,702 bp) dividing the circular genome into a large single-copy (LSC) region (87,873~88,243 bp) and small single-copy (SSC) region (19,740~19,994 bp). Analysis of the phylogenetic tree constructed using the complete CP genome sequences of Morus revealed a monophyletic genus and that M. alba consisted of two clades, M. alba var. alba and M. alba var. multicaulis. The Japanese cultivated germplasms were derived from M. alba var. multicaulis. We propose that the Morus genus be classified into six species, M. nigra, M. notabilis, M. serrata, M. celtidifolia, M. rubra, and M. alba with two subspecies, M. alba var. alba and M. alba var. multicaulis. Our findings provide a valuable resource for the classification, domestication, and breeding improvement of mulberry.
Collapse
|
9
|
Fei CH, Tang SS, Shang SH, Dai J, Wang XY, Wang S, Liu WQ, Wang XF. Conspecific pollen advantage mediated by the extragynoecial compitum and its potential to resist interspecific reproductive interference between two Sagittaria species. FRONTIERS IN PLANT SCIENCE 2022; 13:956193. [PMID: 35937372 PMCID: PMC9354020 DOI: 10.3389/fpls.2022.956193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
The extragynoecial compitum formed by the incomplete fusion of carpel margins, while allowing intercarpellary growth of pollen tubes in apocarpous angiosperms, may also increase the risk of reproductive interference caused by heterospecific pollen (HP) deposition. In Sagittaria, congeneric HP tubes grow via different paths and enter the ovules later than conspecific pollen (CP) tubes. However, it is unclear how the growth advantage of the CP tube helps ensure reproductive success when HP is deposited on the stigmas. We performed molecular characterization of interspecies-pollinated seeds to examine the consequences of interspecific pollen deposition between Sagittaria pygmaea and S. trifolia. We also conducted CP-HP (1:1) mixed pollination and delayed CP pollination treatments to explore the seed-siring abilities of CP and HP. Our results showed that although HP could trigger the development of fruits, the interspecies-pollinated seeds contained partially developed embryos and could not germinate. More than 70% of the embryos in these seeds were molecularly identified as hybrids of both species, suggesting that HP tubes could enter the ovules and fertilize the egg cells. Moreover, CP could sire more offspring (≥70%) after the CP-HP (1:1) mixed pollination treatment, even when HP reached the stigma 0.5-1 h earlier than CP (≥50%). Following adequate CP vs. HP (1:1) pollination on carpels on two sides of the apocarpous gynoecium, both species produced > 70% conspecific seeds, indicating that the CP tubes could occupy ovules that should be occupied by HP via the extragynoecial compitum. Our results reveal that in Sagittaria, pollen deposition from co-existing congeneric heterospecies leads to interspecific seed discounting. However, the CP advantage mediated by the extragynoecial compitum is an effective strategy to mitigate the effects of interspecific pollen deposition. This study improves our understanding of how apocarpous angiosperms with an extragynoecial compitum can maintain species stability and mitigate the negative reproductive interference effect from sympatrically distributed related species.
Collapse
Affiliation(s)
- Cai-Hong Fei
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Sha-Sha Tang
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Shu-He Shang
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Jie Dai
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Xin-Yi Wang
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Shuai Wang
- College of Life Science, Hengyang Normal University, Hengyang, China
| | - Wei-Qi Liu
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiao-Fan Wang
- College of Life Sciences, Wuhan University, Wuhan, China
| |
Collapse
|
10
|
Zou TT, Wang CH, Lyu ST, Yu X, Deng LX, Liu WQ, Dai J, Wang XF. Effects of heterospecific pollen on stigma behavior in Campsis radicans: Causes and consequences. AMERICAN JOURNAL OF BOTANY 2022; 109:1004-1015. [PMID: 35567497 DOI: 10.1002/ajb2.1865] [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: 09/12/2021] [Revised: 04/18/2022] [Accepted: 04/19/2022] [Indexed: 06/15/2023]
Abstract
PREMISE Pollinator sharing of co-flowering plants may result in interspecific pollen receipt with a fitness cost. However, the underlying factors that determine the effects of heterospecific pollen (HP) are not fully understood. Moreover, the cost of stigma closure induced by HP may be more severe for plants with special touch-sensitive stigmas than for plants with non-touch-sensitive stigmas. Very few studies have assessed HP effects on stigma behavior. METHODS We conducted hand-pollination experiments with 10 HP donors to estimate HP effects on stigma behavior and stigmatic pollen germination in Campsis radicans (Bignoniaceae) at low and high pollen loads. We assessed the role of phylogenetic distance between donor and recipient, pollen size, and pollen aperture number in mediating HP effects. Additionally, we observed pollen tube growth to determine the conspecific pollen-tube-growth advantage. RESULTS Stigma behavior differed significantly with HP of different species. Pollen load increased, while pollen size decreased, the percentage of permanent closure and stigmatic germination of HP. Stigmatic HP germination increased with increasing aperture number. However, HP effects did not depend on phylogenetic distance. In addition, conspecific pollen had a pollen-tube-growth advantage over HP. CONCLUSIONS Our results provide a good basis for understanding the stigma-pollen recognition process of plant taxa with touch-sensitive stigmas. We concluded that certain flowering traits drive the HP effects on the post-pollination period. To better understand the impact of pollinator sharing and interspecific pollen transfer on plant evolution, we highlight the importance of evaluating more factors that determine HP effects at the community level.
Collapse
Affiliation(s)
- Ting-Ting Zou
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Chun-Hui Wang
- Ecology and Environment Monitoring and Scientific Research Center, Yangtze Basin Ecology and Environment Administration, Ministry of Ecology and Environment of the People's Republic of China, Wuhan, 430010, China
| | - Sen-Tao Lyu
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xiaolei Yu
- State Key Laboratory of Hybrid Rice, Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Lu-Xi Deng
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Wei-Qi Liu
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Jie Dai
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xiao-Fan Wang
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| |
Collapse
|
11
|
Smith GX, Swartz MT, Spigler RB. Causes and consequences of variation in heterospecific pollen receipt in Oenothera fruticosa. AMERICAN JOURNAL OF BOTANY 2021; 108:1612-1624. [PMID: 34460097 PMCID: PMC9291898 DOI: 10.1002/ajb2.1720] [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: 02/12/2021] [Accepted: 05/25/2021] [Indexed: 05/05/2023]
Abstract
PREMISE Heterospecific pollen transfer, the transfer of pollen between species, is common among co-flowering plants, yet the amount of pollen received is extremely variable among species. Intraspecific variation in heterospecific pollen receipt can be even greater, but we lack an understanding of its causes and fitness consequences in wild populations. METHODS We examined potential drivers of variation in heterospecific pollen receipt in Oenothera fruticosa. We evaluated the relationship between heterospecific and conspecific pollen receipt and considered how visitation by different pollinator groups, local floral neighborhood composition, and flowering phenology affect the total amount and proportion of heterospecific pollen received. Finally, we tested whether variation in heterospecific pollen receipt translated into lower seed production. RESULTS Heterospecific pollen was ubiquitous on O. fruticosa stigmas, but the amount received was highly variable and unrelated to conspecific pollen receipt. Heterospecific pollen receipt depended on pollinator type, the proportion of nearby conspecific flowers, and flowering date. Significant interactions revealed that the effects of pollinator type and neighborhood were not independent, further contributing to variation in heterospecific pollen. Naturally occurring levels of heterospecific pollen were sufficient to negatively impact seed set, but large amounts of conspecific pollen counteracted this detrimental effect. CONCLUSIONS Although selection could act on floral traits that attract quality pollinators and promote synchronous flowering in O. fruticosa, the risk of heterospecific pollen is equally dependent on local floral context. This work highlights how extrinsic and intrinsic factors contribute to intraspecific variation in heterospecific pollen receipt in wild plants, with significant fitness consequences.
Collapse
Affiliation(s)
- Gerard X. Smith
- Department of BiologyTemple University1900 N. 12 StreetPhiladelphiaPA19122USA
| | - Mark T. Swartz
- The Pennsylvania Department of Military and Veterans AffairsFort Indiantown Gap National Guard Training CenterAnnvillePA17003USA
| | - Rachel B. Spigler
- Department of BiologyTemple University1900 N. 12 StreetPhiladelphiaPA19122USA
| |
Collapse
|
12
|
Erarslan ZB, Karagöz S, Kültür Ş. Comparative Morphological and Anatomical Studies on Morus Species (Moraceae) in Turkey. Turk J Pharm Sci 2021; 18:157-166. [PMID: 33900701 DOI: 10.4274/tjps.galenos.2020.02779] [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: 12/01/2022]
Abstract
Objectives Morus alba L., Morus nigra L., and Morus rubra L. are widely cultivated in many countries due to their nutritive, economic, and medicinal value. In this study, comparative morphological and anatomical studies on three common Morus L. species found in Turkey were carried out. According to the results, differences regarding the morphological and anatomical features of these species were described, and the data were displayed in detailed photographs. Materials and Methods Specimens collected from different provinces of Turkey were studied. In the anatomical studies, investigations were performed on transversal and superficial sections of the leaves. All sections were stained with chloral hydrate and Sartur solution and were then examined using an Olympus BH2 light microscope. Results Significant diagnostic characteristics were found, such as trichome types, stomatal measurements, the stomatal index, and the density ratio of the parenchyma and collenchyma layers. Some morphological features of the leaves also showed prominent differences. Conclusion Our results may contribute to the taxonomy of Morus species for future work and be helpful in species diagnosis.
Collapse
Affiliation(s)
- Zeynep Büşra Erarslan
- İstanbul University Faculty of Pharmacy, Department of Pharmaceutical Botany, İstanbul, Turkey
| | - Sevde Karagöz
- İstanbul University Faculty of Pharmacy, Department of Pharmaceutical Botany, İstanbul, Turkey
| | - Şükran Kültür
- İstanbul University Faculty of Pharmacy, Department of Pharmaceutical Botany, İstanbul, Turkey
| |
Collapse
|
13
|
Zaya DN, Leicht-Young SA, Pavlovic NB, Ashley MV. Heterospecific pollination by an invasive congener threatens the native American bittersweet, Celastrus scandens. PLoS One 2021; 16:e0248635. [PMID: 33755682 PMCID: PMC7987179 DOI: 10.1371/journal.pone.0248635] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 03/02/2021] [Indexed: 11/19/2022] Open
Abstract
Invasive plants have the potential to interfere with native species’ reproductive success through a number of mechanisms, including heterospecific pollination and hybridization. This study investigated reproductive interactions between a native North American woody vine (American bittersweet, Celastrus scandens) and an introduced congener (oriental bittersweet, C. orbiculatus). The decline of C. scandens in the eastern portion of its range is coincident with the introduction and spread of C. orbiculatus, and the two species are known to hybridize. The relationship between proximity and floral production of conspecific and heterospecific males on fertilization and hybridization rates was measured at a field site in northwestern Indiana, USA where both species occur and reproduce. We found that the invasive vine had an extreme advantage in both male and female floral production, producing nearly 200 times more flowers per staminate plant and 65 times more flowers per pistillate plant than the native. Using nuclear microsatellite DNA markers we found that hybridization rates were asymmetric; 39% of the C. scandens seeds tested were hybrids, compared to only 1.6% of C. orbiculatus seeds. The asymmetric hybridization rates were likely not solely due to greater abundance of C. orbiculatus pollen because experimental hand crosses revealed that C. scandens had a higher rate (41%) of heterospecific fertilization than C. orbiculatus (2.4%). We previously reported that few hybrids were observed in the wild, and hybrids had greatly reduced fecundity. Thus, in our system, the threat posed by heterospecific pollen is not replacement by hybrids or introgression, but rather asymmetric reproductive interference. Reproductive interference extended to distances as great as 100 meters, thus, efforts to conserve the native species must reduce its exposure to C. orbiculatus over a relatively large spatial scale.
Collapse
Affiliation(s)
- David N. Zaya
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
- * E-mail:
| | - Stacey A. Leicht-Young
- U.S. Geological Survey, Great Lakes Science Center, Chesterton, Indiana, United States of America
| | - Noel B. Pavlovic
- U.S. Geological Survey, Great Lakes Science Center, Chesterton, Indiana, United States of America
| | - Mary V. Ashley
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| |
Collapse
|
14
|
Streher NS, Bergamo PJ, Ashman TL, Wolowski M, Sazima M. Effect of heterospecific pollen deposition on pollen tube growth depends on the phylogenetic relatedness between donor and recipient. AOB PLANTS 2020; 12:plaa016. [PMID: 32665826 PMCID: PMC7333672 DOI: 10.1093/aobpla/plaa016] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 05/11/2020] [Indexed: 05/30/2023]
Abstract
Co-flowering plant species may interact via pollinators leading to heterospecific pollen transfer with consequences for plant reproduction. What determines the severity of heterospecific pollen effect on conspecific pollen performance is unclear, but it may depend on the phylogenetic relatedness of the interactors (pollen donors and recipient). The heterospecific pollen effect might also depend on the extent to which plants are exposed to heterospecific pollen over ecological or evolutionary timescales. For instance, generalist-pollinated plant species might tolerate heterospecific pollen more than specialists. Here, we tested whether heterospecific pollen effects are stronger between closely related species than phylogenetically distant ones in a tropical highland community. Then, based on these results, we determined whether responses to heterospecific pollen were stronger in generalized vs. specialized plant species. We applied heterospecific pollen from close (congeneric) or distant (different families) donors alone or with conspecific pollen on stigmas of three recipient species (one generalist, Sisyrinchium wettsteinii; and two specialists, Fuchsia campos-portoi and Fuchsia regia) and scored pollen tube performance in styles. In all species, pollen from closely related donors grew pollen tubes to the base of the style indicating a high potential to interfere with seed set. Conversely, distantly related heterospecific pollen had no effect on either specialist Fuchsia species, whereas enhanced performance of conspecific pollen was observed in generalist S. wettsteinii. The strong effect of phylogenetic relatedness of donor and recipient might have obscured the role of pollination specialization, at least for the three species examined here. Therefore, phylogenetic relatedness mediated the effect of heterospecific pollen on post-pollination success, with possible consequences for reproductive trait evolution and community assembly for further studies to explore.
Collapse
Affiliation(s)
- Nathália Susin Streher
- Graduate Program in Plant Biology, University of Campinas, Campinas, SP, Brazil
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Tia-Lynn Ashman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Marina Wolowski
- Institute of Natural Sciences, Federal University of Alfenas, Alfenas, MG, Brazil
| | - Marlies Sazima
- Plant Biology Department, Institute of Biology, University of Campinas, Campinas, SP, Brazil
| |
Collapse
|
15
|
Nishida S, Takakura KI, Naiki A, Nishida T. Habitat partitioning in native Geranium species through reproductive interference. ANNALS OF BOTANY 2020; 125:651-661. [PMID: 31900487 PMCID: PMC7102965 DOI: 10.1093/aob/mcz210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 12/30/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND AIMS Heterospecific pollen transfer may reduce the fitness of recipient species, a phenomenon known as reproductive interference. A theoretical study has predicted that distributions of species pairs affected by reproductive interference may be syntopic under negligible reproductive interference, sympatric but with partitioning at small spatial scale (i.e. allotopic) under weak interference, or exclusive when reproductive interference is strong. Verifying these predictions is essential for evaluation of the applicability of reproductive interference as a general assembly rule of biological communities. The aim of this study was to test these predictions in two sympatrically distributed wild Geranium species, G. thunbergii and G. wilfordii. METHODS To measure the effect of reproductive interference, the associations between the relative abundance of the counterpart species and seed set in the focal species, and seed set reduction following mixed pollination, were analysed. The possibility of hybridization with viable offspring was examined by genotyping plants in the field and after mixed pollination. Fertility of putative hybrids was based on their seed set and the proportion of pollen grains with apertural protrusions. A transect study was conducted to examine spatial partitioning, and possible influences of environmental conditions (canopy openness and soil moisture content) on partitioning between the species were analysed. KEY RESULTS Neither abundance of the counterpart species nor heterospecific pollen deposition significantly affected seed set in the focal species, and hybridization between species was almost symmetrical. Putative hybrids had low fertility. The two species were exclusively distributed at small scale, although environmental conditions were not significantly different between them. CONCLUSIONS The allotopy of the two species may be maintained by relatively weak reproductive interference through bidirectional hybridization. Re-evaluation of hybridization may allow ongoing or past reproductive interference to be recognized and provide insight into the distributional relationships between the interacting plants.
Collapse
Affiliation(s)
- Sachiko Nishida
- Nagoya University Museum, Furo-cho, Chikusa-ku, Nagoya, Japan
| | - Koh-Ichi Takakura
- School of Environmental Science, University of Shiga Prefecture, Yasaka-cho, Hikone, Japan
| | - Akiyo Naiki
- Iriomote Station, Tropical Biosphere Research Center, University of the Ryukyus, Taketomi-cho, Yaeyama-gun, Japan
| | - Takayoshi Nishida
- School of Environmental Science, University of Shiga Prefecture, Yasaka-cho, Hikone, Japan
| |
Collapse
|
16
|
Xuan Y, Wu Y, Li P, Liu R, Luo Y, Yuan J, Xiang Z, He N. Molecular phylogeny of mulberries reconstructed from ITS and two cpDNA sequences. PeerJ 2019; 7:e8158. [PMID: 31844573 PMCID: PMC6911693 DOI: 10.7717/peerj.8158] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 11/04/2019] [Indexed: 11/20/2022] Open
Abstract
Background Species in the genus Morus (Moraceae) are deciduous woody plants of great economic importance. The classification and phylogenetic relationships of Morus, especially the abundant mulberry resources in China, is still undetermined. Internal transcribed spacer (ITS) regions are among the most widely used molecular markers in phylogenetic analyses of angiosperms. However, according to the previous phylogenetic analyses of ITS sequences, most of the mulberry accessions collected in China were grouped into the largest clade lacking for phylogenetic resolution. Compared with functional ITS sequences, ITS pseudogenes show higher sequence diversity, so they can provide useful phylogenetic information. Methods We sequenced the ITS regions and the chloroplast DNA regions TrnL-TrnF and TrnT-TrnL from 33 mulberry accessions, and performed phylogenetic analyses to explore the evolution of mulberry. Results We found ITS pseudogenes in 11 mulberry accessions. In the phylogenetic tree constructed from ITS sequences, clade B was separated into short-type sequence clades (clades 1 and 2), and a long-type sequence clade (clade 3). Pseudogene sequences were separately clustered into two pseudogroups, designated as pseudogroup 1 and pseudogroup 2. The phylogenetic tree generated from cpDNA sequences also separated clade B into two clades. Conclusions Two species were separated in clade B. The existence of three connection patterns and incongruent distribution patterns between the phylogenetic trees generated from cpDNA and ITS sequences suggested that the ITS pseudogene sequences connect with genetic information from the female progenitor. Hybridization has played important roles in the evolution of mulberry, resulting in low resolution of the phylogenetic analysis based on ITS sequences. An evolutionary pattern illustrating the evolution history of mulberry is proposed. These findings have significance for the conservation of local mulberry resources. Polyploidy, hybridization, and concerted evolution have all played the roles in the evolution of ITS sequences in mulberry. This study will expand our understanding of mulberry evolution.
Collapse
Affiliation(s)
- Yahui Xuan
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Yue Wu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Peng Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Ruiling Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Yiwei Luo
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Jianglian Yuan
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Zhonghuai Xiang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Ningjia He
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| |
Collapse
|
17
|
Moreira-Hernández JI, Muchhala N. Importance of Pollinator-Mediated Interspecific Pollen Transfer for Angiosperm Evolution. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2019. [DOI: 10.1146/annurev-ecolsys-110218-024804] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Understanding how pollen moves between species is critical to understanding speciation, diversification, and evolution of flowering plants. For co-flowering species that share pollinators, competition through interspecific pollen transfer (IPT) can profoundly impact floral evolution, decreasing female fitness via heterospecific pollen deposition on stigmas and male fitness via pollen misplacement during visits to heterospecific flowers. The pollination literature demonstrates that such reproductive interference frequently selects for reproductive character displacement in floral traits linked to pollinator attraction, pollen placement, and mating systems and has also revealed that IPT between given pairs of species is typically asymmetric. More recent work is starting to elucidate its importance to the speciation process, clarifying the link between IPT and current and historical patterns of hybridization, the evolution of phenotypic novelty through adaptive introgression, and the rise of reproductive isolation. Our review aims to stimulate further research on IPT as a ubiquitous mechanism that plays a central role in angiosperm diversification.
Collapse
Affiliation(s)
- Juan Isaac Moreira-Hernández
- Department of Biology and Whitney R. Harris World Ecology Center, University of Missouri–St. Louis, St. Louis, Missouri 63121, USA;,
| | - Nathan Muchhala
- Department of Biology and Whitney R. Harris World Ecology Center, University of Missouri–St. Louis, St. Louis, Missouri 63121, USA;,
| |
Collapse
|
18
|
Takemori A, Naiki A, Takakura KI, Kanaoka MM, Nishida S. Comparison of mechanisms of reproductive interference in Taraxacum. ANNALS OF BOTANY 2019; 123:1017-1027. [PMID: 30715137 PMCID: PMC6589510 DOI: 10.1093/aob/mcz007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 01/07/2019] [Indexed: 05/30/2023]
Abstract
BACKGROUND AND AIMS Reproductive interference may reduce fitness of either of the involved species, with potentially important ecological and evolutionary consequences. Except for the effect of shared pollinators on reproductive success, however, mechanisms underlying reproductive interference have been little studied, even though the severity of its impact may depend on the specific mechanism. The aim of this study was therefore to explore the mechanisms of reproductive interference between Taraxacum japonicum (native to Japan) and Taraxacum officinale (alien). METHODS In a field survey, the association between alien species density and seed set in T. japonicum, and whether pollinator behaviour indicated a preference for the alien, were examined. Effects of heterospecific pollen deposition were measured in a series of hand pollination experiments, including mixed pollination experiments in which the order of application of conspecific and heterospecific pollen was varied. Finally, to investigate hybridization frequency, the parentage of seedlings produced following natural, mixed or heterospecific pollination was compared. KEY RESULTS Alien species density did not negatively affect native seed set, nor did pollinators appear to have a preference for alien flowers. The hand pollination experiments showed that heterospecific pollen deposition adversely affected native seed set, especially when alien pollen was applied before conspecific pollen. No viable hybrids were found following natural pollination, which suggests that hybridization might be a rare event. CONCLUSION Among the examined mechanisms, heterospecific pollen deposition might have the largest deleterious effect on the native species. This effect is frequency dependent; thus, a positive feedback loop may cause the effect on the population dynamics to increase over time, with the result that the alien might eventually displace the native in a population. Effects of the examined mechanisms on population dynamics should be investigated further to improve understanding of the impact of reproductive interference on the structure of plant communities.
Collapse
Affiliation(s)
- Akane Takemori
- Graduate School of Education, Okayama University, Kita-ku, Okayama City, Japan
| | - Akiyo Naiki
- Iriomote Station, Tropical Biosphere Research Center, University of the Ryukyus, Yaeyama-gun, Japan
| | - Ko-Ichi Takakura
- School of Environmental Science, The University of Shiga Prefecture, Hikone, Japan
| | - Masahiro M Kanaoka
- Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya, Japan
| | | |
Collapse
|
19
|
Bunge A, Diemont SAW, Bunge JA, Harris S. Urban foraging for food security and sovereignty: quantifying edible forest yield in Syracuse, New York using four common fruit- and nut-producing street tree species. JOURNAL OF URBAN ECOLOGY 2019. [DOI: 10.1093/jue/juy028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Avalon Bunge
- Education Department, The Maritime Aquarium at Norwalk, Norwalk, CT 06854, USA
| | - Stewart A W Diemont
- Department of Environmental and Forest Biology, College of Environmental Science and Forestry, State University of New York, Syracuse, NY 13210, USA
| | - John A Bunge
- Department of Statistical Sciences, Cornell University, Ithaca, NY 14850, USA
| | - Stephen Harris
- Syracuse City Arborist’s Office, Syracuse, NY 13210, USA
| |
Collapse
|
20
|
Yan LJ, Burgess KS, Milne R, Fu CN, Li DZ, Gao LM. Asymmetrical natural hybridization varies among hybrid swarms between two diploid Rhododendron species. ANNALS OF BOTANY 2017; 120:51-61. [PMID: 28444136 PMCID: PMC5737508 DOI: 10.1093/aob/mcx039] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 03/14/2017] [Indexed: 05/23/2023]
Abstract
Background and Aims The extent to which hybridization leads to gene flow between plant species depends on the structure of hybrid populations. However, if this varies between locations, species barriers might prove permeable in some locations but not in others. To assess possible variation in hybrid population structure, the magnitude and direction of natural hybridization between two Chinese endemic species, Rhododendron spiciferum and Rhododendron spinuliferum , were evaluated. Methods Thirteen nuclear microsatellite markers were employed to characterize 566 individuals collected from 15 non-allopatric populations and nine allopatric parental populations. Chloroplast DNA (cpDNA) sequences were obtained from a subset of samples. Genetic structure and direction of gene flow was determined using a combination of STRUCTURE and NEWHYBRIDS analysis. Key Results Nuclear analysis revealed that parental taxa formed two genetically distinct clusters and hybrids shared the genetic background of both parents and did not form a separate genetic lineage. Overall, hybrid swarms were dominated by early- and later-generation hybrids, with a significantly higher proportion of hybrids (59·6 %) possessing >50 % R. spiciferum-like nuclear germplasm. The cpDNA analysis further indicated that a significantly greater proportion of hybrids (61·1 %) possessed the R. spiciferum cpDNA haplotype. Conclusions Gene flow between R. spiciferum and R. spinuliferum was found to be bidirectional in 14 of the 15 hybrid swarms and asymmetrical in six hybrid swarms. Asymmetrical gene flow was evident for only nuclear DNA (nDNA) in two populations, for only cpDNA in three populations, and for both nDNA and cpDNA in one population. Collectively, the variation in genetic structure found among the 15 hybrid swarms suggests that introgression rather than hybrid speciation is a more likely outcome of hybridization between these hybridizing taxa.
Collapse
Affiliation(s)
- Li-Jun Yan
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
- Germplasm Bank of Wild Species in Southwest China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- College of Vocational and Technical Education, Yunnan Normal University, Kunming 650092, China
| | - Kevin S. Burgess
- Department of Biology, College of Letters & Sciences, Columbus State University, University System of Georgia, 163A LeNoir Hall, Columbus, GA 31907-5645, USA
| | - Richard Milne
- Institute of Molecular Plant Sciences, University of Edinburgh, King’s Buildings, Edinburgh EH9 3JH, UK
| | - Chao-Nan Fu
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - De-Zhu Li
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
- Germplasm Bank of Wild Species in Southwest China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lian-Ming Gao
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| |
Collapse
|
21
|
Nishida S, Hashimoto K, Kanaoka MM, Takakura KI, Nishida T. Variation in the strength of reproductive interference from an alien congener to a native species in Taraxacum. JOURNAL OF PLANT RESEARCH 2017; 130:125-134. [PMID: 27659681 DOI: 10.1007/s10265-016-0865-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 08/08/2016] [Indexed: 06/06/2023]
Abstract
Reproductive interference (RI) may be a contributing factor to the displacement of native species by an alien congener, and RI strength has been shown theoretically to affect distributional relationships between species. Thus, variations in RI strength from alien to native species result in different consequences of invasions and efforts to conserve native species, but the variations have seldom been examined empirically. We therefore investigated RI strength variations from the alien species Taraxacum officinale and its hybrids to eight populations of native dandelions, four T. japonicum populations and two populations each of two subspecies of T. platycarpum. We examined the association between alien relative abundance and native seed set in field surveys, and we also performed hand-pollination experiments to investigate directly the sensitivity of native flowers to alien pollen. We found that the effect of alien relative abundance on native seed set of even the same native species could differ greatly in different regions, and that the sensitivity of native flowers to alien pollen was also dependent on region. Our results, together with those of previous studies, show that RI from the alien to the native species is strong in regions where the alien species outnumbers the native species and marginal where it does not; this result suggests that alien RI can critically affect distributional relationships between native and alien species. Our study highlights the importance of performing additional empirical investigations of RI strength variation and of giving due attention to alien RI in efforts to conserve regional native biodiversity.
Collapse
Affiliation(s)
- Sachiko Nishida
- Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
- Nagoya University Museum, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
| | - Keisuke Hashimoto
- Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Masahiro M Kanaoka
- Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Ko-Ichi Takakura
- School of Environmental Science, The University of Shiga Prefecture, Yasaka-cho, Hikone, 552-0057, Japan
| | - Takayoshi Nishida
- School of Environmental Science, The University of Shiga Prefecture, Yasaka-cho, Hikone, 552-0057, Japan
| |
Collapse
|
22
|
Hersh E, Grimm J, Whitton J. Attack of the clones: reproductive interference between sexuals and asexuals in the Crepis agamic complex. Ecol Evol 2016; 6:6473-6483. [PMID: 27777723 PMCID: PMC5058521 DOI: 10.1002/ece3.2353] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 06/30/2016] [Accepted: 07/04/2016] [Indexed: 02/02/2023] Open
Abstract
Negative reproductive interactions are likely to be strongest between close relatives and may be important in limiting local coexistence. In plants, interspecific pollen flow is common between co-occurring close relatives and may serve as the key mechanism of reproductive interference. Agamic complexes, systems in which some populations reproduce through asexual seeds (apomixis), while others reproduce sexually, provide an opportunity to examine effects of reproductive interference in limiting coexistence. Apomictic populations experience little or no reproductive interference, because apomictic ovules cannot receive pollen from nearby sexuals. Oppositely, apomicts produce some viable pollen and can exert reproductive interference on sexuals by siring hybrids. In the Crepis agamic complex, sexuals co-occur less often with other members of the complex, but apomicts appear to freely co-occur with one another. We identified a mixed population and conducted a crossing experiment between sexual diploid C. atribarba and apomictic polyploid C. barbigera using pollen from sexual diploids and apomictic polyploids. Seed set was high for all treatments, and as predicted, diploid-diploid crosses produced all diploid offspring. Diploid-polyploid crosses, however, produced mainly polyploidy offspring, suggesting that non-diploid hybrids can be formed when the two taxa meet. Furthermore, a small proportion of seeds produced in open-pollinated flowers was also polyploid, indicating that polyploid hybrids are produced under natural conditions. Our results provide evidence for asymmetric reproductive interference, with pollen from polyploid apomicts contributing to reduce the recruitment of sexual diploids in subsequent generations. Existing models suggest that these mixed sexual-asexual populations are likely to be transient, eventually leading to eradication of sexual individuals from the population.
Collapse
Affiliation(s)
- Evan Hersh
- Department of Botany and Biodiversity Research CentreThe University of British Columbia6270 University BoulevardVancouverBritish ColumbiaCanadaV6T 1Z4
| | - Jaime Grimm
- Department of Botany and Biodiversity Research CentreThe University of British Columbia6270 University BoulevardVancouverBritish ColumbiaCanadaV6T 1Z4
- Present address: Department of BiologyMcGill University1205 Dr. Penfield AvenueMontrealQuébecCanadaH3A 1B1
| | - Jeannette Whitton
- Department of Botany and Biodiversity Research CentreThe University of British Columbia6270 University BoulevardVancouverBritish ColumbiaCanadaV6T 1Z4
| |
Collapse
|
23
|
Briggs HM, Anderson LM, Atalla LM, Delva AM, Dobbs EK, Brosi BJ. Heterospecific pollen deposition in Delphinium barbeyi: linking stigmatic pollen loads to reproductive output in the field. ANNALS OF BOTANY 2016; 117:341-7. [PMID: 26658101 PMCID: PMC4724048 DOI: 10.1093/aob/mcv175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 08/01/2015] [Accepted: 09/30/2015] [Indexed: 05/22/2023]
Abstract
BACKGROUND AND AIMS Most pollinators are generalists and therefore are likely to transfer heterospecific pollen among co-flowering plants. Most work on the impacts of heterospecific pollen deposition on plant fecundity has utilized hand-pollination experiments in greenhouse settings, and we continue to know very little about the reproductive effects of heterospecific pollen in field settings. METHODS We explored how patterns of naturally deposited heterospecific pollen relate to the reproductive output of Delphinium barbeyi, a common subalpine perennial herb in the Rocky Mountains (USA). We assessed a wide range of naturally occurring heterospecific pollen proportions and pollen load sizes, and linked stigmatic pollen deposition directly to seed set in individual carpels in the field. KEY RESULTS We found that heterospecific pollen deposition in D. barbeyi is common, but typically found at low levels across stigmas collected in our sites. Neither conspecific nor heterospecific pollen deposition was related to carpel abortion. By contrast, we saw a significant positive relationship between conspecific pollen amount and viable seed production, as well as a significant negative interaction between the effects of conspecific pollen and heterospecific pollen amount, whereby the effect of conspecific pollen on viable seed production became weaker with greater heterospecific deposition on stigmas. CONCLUSIONS To our knowledge, this is the first demonstration of a relationship between heterospecific pollen and seed production in a field setting. In addition, it is the first report of an interaction between conspecific and heterospecific pollen quantities on seed production. These findings, taken with the results from other studies, suggest that greenhouse hand-pollination studies and field studies should be more tightly integrated in future work to better understand how heterospecific pollen transfer can be detrimental for plant reproduction.
Collapse
Affiliation(s)
- Heather M Briggs
- Department of Environmental Studies, University of California, Santa Cruz, CA 95064, USA, Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA and
| | - Lucy M Anderson
- Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA and Department of Environmental Sciences, Emory University, Atlanta, GA 30322, USA
| | - Laila M Atalla
- Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA and Department of Environmental Sciences, Emory University, Atlanta, GA 30322, USA
| | - André M Delva
- Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA and Department of Environmental Sciences, Emory University, Atlanta, GA 30322, USA
| | - Emily K Dobbs
- Department of Environmental Sciences, Emory University, Atlanta, GA 30322, USA
| | - Berry J Brosi
- Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA and Department of Environmental Sciences, Emory University, Atlanta, GA 30322, USA
| |
Collapse
|
24
|
Genetic characterization of hybridization between native and invasive bittersweet vines (Celastrus spp.). Biol Invasions 2015. [DOI: 10.1007/s10530-015-0926-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
25
|
Balao F, Casimiro-Soriguer R, García-Castaño JL, Terrab A, Talavera S. Big thistle eats the little thistle: does unidirectional introgressive hybridization endanger the conservation of Onopordum hinojense? THE NEW PHYTOLOGIST 2015; 206:448-458. [PMID: 25401776 DOI: 10.1111/nph.13156] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/28/2014] [Indexed: 06/04/2023]
Abstract
Hybridization is known to have a creative role in plant evolution. However, it can also have negative effects on parental species. Onopordum is a large genus whose species frequently hybridize. In the Southwest Iberian Peninsula, the rare O. hinojense co-occurs with the widely distributed O. nervosum, and hybrids between these two taxa have been described as O. × onubense. In this study we determine the extinction risk in a hybrid zone, both for hybrids and parentals, using analyses of morphological and cytogenetic traits as well as genetic markers and demographic models. To investigate the introgression process we used amplified fragment length polymorphism (AFLP) markers, Bayesian analyses and genome scan methods. Morphology, genome size and molecular markers confirmed homoploid hybridization and also indicated unidirectional backcrossing of F₁ hybrids with O. nervosum, which is likely to swamp O. hinojense, the parental with lower pollen size and a very low fruit set (8%). Genome scan methods revealed several loci significantly deviating from neutrality. Finally, our demographic modeling indicated that the higher fitness of O. nervosum threats the survival of O. hinojense by demographic swamping. Our study provides strong new evidence for a scenario of rapid extinction by unidirectional introgression and demographic swamping. The multifaceted approach used here sheds new light on the role of introgression in plant extinctions.
Collapse
Affiliation(s)
- Francisco Balao
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, 41080, Sevilla, Spain
- Department of Systematic and Evolutionary Botany, University of Vienna, Rennweg 14, 1030, Austria
| | - Ramón Casimiro-Soriguer
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, 41080, Sevilla, Spain
- Departmento de Biología, CASEM, Universidad de Cádiz, Campus Río San Pedro, E-11510, Puerto Real, Spain
| | - Juan Luis García-Castaño
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, 41080, Sevilla, Spain
| | - Anass Terrab
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, 41080, Sevilla, Spain
- Department of Systematic and Evolutionary Botany, University of Vienna, Rennweg 14, 1030, Austria
| | - Salvador Talavera
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, 41080, Sevilla, Spain
| |
Collapse
|
26
|
Invasive conifers reduce seed set of a native Andean cedar through heterospecific pollination competition. Biol Invasions 2014. [DOI: 10.1007/s10530-014-0775-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
27
|
Muchhala N, Johnsen S, Smith SD. Competition for hummingbird pollination shapes flower color variation in Andean solanaceae. Evolution 2014; 68:2275-86. [PMID: 24766107 DOI: 10.1111/evo.12441] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Accepted: 04/14/2014] [Indexed: 11/30/2022]
Abstract
One classic explanation for the remarkable diversity of flower colors across angiosperms involves evolutionary shifts among different types of pollinators with different color preferences. However, the pollinator shift model fails to account for the many examples of color variation within clades that share the same pollination system. An alternate explanation is the competition model, which suggests that color divergence evolves in response to interspecific competition for pollinators, as a means to decrease interspecific pollinator movements. This model predicts color overdispersion within communities relative to null assemblages. Here, we combine morphometric analyses, field surveys, and models of pollinator vision with a species-level phylogeny to test the competition model in the primarily hummingbird-pollinated clade Iochrominae (Solanaceae). Results show that flower color as perceived by pollinators is significantly overdispersed within sites. This pattern is not simply due to phylogenetic history: phylogenetic community structure does not deviate from random expectations, and flower color lacks phylogenetic signal. Moreover, taxa that occur in sympatry occupy a significantly larger volume of color space than those in allopatry, supporting the hypothesis that competition in sympatry drove the evolution of novel colors. We suggest that competition among close relatives may commonly underlie floral divergence, especially in species-rich habitats where congeners frequently co-occur.
Collapse
Affiliation(s)
- Nathan Muchhala
- School of Biological Sciences, University of Nebraska, Lincoln, Nebraska, 68588; Current Address: Department of Biology, University of Missouri - St. Louis, St. Louis, Missouri, 63121.
| | | | | |
Collapse
|
28
|
Weller SG, Sakai AK, Culley TM, Duong L, Danielson RE. Segregation of male-sterility alleles across a species boundary. J Evol Biol 2014; 27:429-36. [PMID: 24417506 DOI: 10.1111/jeb.12312] [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: 09/05/2013] [Accepted: 11/26/2013] [Indexed: 11/29/2022]
Abstract
Hybrid zones may serve as bridges permitting gene flow between species, including alleles influencing the evolution of breeding systems. Using greenhouse crosses, we assessed the likelihood that a hybrid zone could serve as a conduit for transfer of nuclear male-sterility alleles between a gynodioecious species and a hermaphroditic species with very rare females in some populations. Segregation patterns in progeny of crosses between rare females of hermaphroditic Schiedea menziesii and hermaphroditic plants of gynodioecious Schiedea salicaria heterozygous at the male-sterility locus, and between female S. salicaria and hermaphroditic plants from the hybrid zone, were used to determine whether male-sterility was controlled at the same locus in the parental species and the hybrid zone. Segregations of females and hermaphrodites in approximately equal ratios from many of the crosses indicate that the same nuclear male-sterility allele occurs in the parent species and the hybrid zone. These rare male-sterility alleles in S. menziesii may result from gene flow from S. salicaria through the hybrid zone, presumably facilitated by wind pollination in S. salicaria. Alternatively, rare male-sterility alleles might result from a reversal from gynodioecy to hermaphroditism in S. menziesii, or possibly de novo evolution of male sterility. Phylogenetic analysis indicates that some species of Schiedea have probably evolved separate sexes independently, but not in the lineage containing S. salicaria and S. menziesii. High levels of selfing and expression of strong inbreeding depression in S. menziesii, which together should favour females in populations, argue against a reversal from gynodioecy to hermaphroditism in S. menziesii.
Collapse
Affiliation(s)
- S G Weller
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, USA
| | | | | | | | | |
Collapse
|
29
|
Nishida S, Kanaoka MM, Hashimoto K, Takakura KI, Nishida T. Pollen-pistil interactions in reproductive interference: comparisons of heterospecific pollen tube growth from alien species between two nativeTaraxacumspecies. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12165] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Keisuke Hashimoto
- Graduate School of Environmental Studies; Nagoya University; Nagoya 464-8601 Japan
| | - Koh-Ichi Takakura
- Osaka City Institute of Public Health and Environmental Science; Tennoji-ku Osaka 543-0026 Japan
| | - Takayoshi Nishida
- School of Environmental Science; The University of Shiga Prefecture; Hikone 522-0057 Japan
| |
Collapse
|
30
|
Liao K, Gituru RW, Guo YH, Wang QF. The presence of co-flowering species facilitates reproductive success of Pedicularis monbeigiana (Orobanchaceae) through variation in bumble-bee foraging behaviour. ANNALS OF BOTANY 2011; 108:877-84. [PMID: 21831855 PMCID: PMC3177687 DOI: 10.1093/aob/mcr216] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 06/24/2011] [Indexed: 05/20/2023]
Abstract
Background and Aims The presence of co-flowering species can alter pollinator foraging behaviour and, in turn, positively or negatively affect the reproductive success of the focal species. Such interactions were investigated between a focal species, Pedicularis monbeigiana, and a co-flowering species, Vicia dichroantha, which was mediated by behaviour alteration of the shared bumble-bee pollinator. Methods Floral display size and floral colour change of P. monbeigiana were compared between pure (P. monbeigiana only) and mixed (P. monbeigiana and V. dichroantha) plots in two populations. Pollinator visitation rates, interspecific floral switching and successive within-plant pollinator visits were recorded. In addition, supplemental pollination at plant level was performed, and the fruit set and seed set were analysed in pure and mixed plots with different densities of P. monbeigiana. Key Results Pollinator visitation rates were dramatically higher in mixed plots than in pure plots. The higher pollinator visitation rates were recorded in both low- and high-density plots. In particular, successive flower visits within an individual plant were significantly lower in mixed plots. Supplemental pollination significantly increased fruit set and seed set of individuals in pure plots, while it only marginally increased seed set per fruit of plants in mixed plots. Conclusions The presence of V. dichroantha can facilitate pollination and increase female reproductive success of P. monbeigiana via both quantity (mitigating pollinator limitation) and quality (reducing geitonogamy) effects. This study suggests that successive pollinator movements among flowers within a plant, as well as pollinator visitation rates and interspecific flower switching, may be important determinants of the direction and mechanisms of interaction between species.
Collapse
Affiliation(s)
- Kuo Liao
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Robert W. Gituru
- Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, 430074, China
| | - You-Hao Guo
- Laboratory of Plant Systematics and Evolutionary Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China
- For correspondence. E-mail or
| | - Qing-Feng Wang
- Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, 430074, China
- For correspondence. E-mail or
| |
Collapse
|
31
|
Martinell MC, López-Pujol J, Bosch M, Blanché C. Low genetic variability in the rare, recently differentiated Aquilegia paui (Ranunculaceae). BIOCHEM SYST ECOL 2010. [DOI: 10.1016/j.bse.2010.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
32
|
Brown GP, Shine R. Beyond size-number trade-offs: clutch size as a maternal effect. Philos Trans R Soc Lond B Biol Sci 2009; 364:1097-106. [PMID: 19324614 PMCID: PMC2666681 DOI: 10.1098/rstb.2008.0247] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Traditionally, research on life-history traits has viewed the link between clutch size and offspring size as a straightforward linear trade-off; the product of these two components is taken as a measure of maternal reproductive output. Investing more per egg results in fewer but larger eggs and, hence, offspring. This simple size-number trade-off has proved attractive to modellers, but our experimental studies on keelback snakes (Tropidonophis mairii, Colubridae) reveal a more complex relationship between clutch size and offspring size. At constant water availability, the amount of water taken up by a snake egg depends upon the number of adjacent eggs. In turn, water uptake affects hatchling size, and therefore an increase in clutch size directly increases offspring size (and thus fitness under field conditions). This allometric advantage may influence the evolution of reproductive traits such as growth versus reproductive effort, optimal age at female maturation, the body-reserve threshold required to initiate reproduction and nest-site selection (e.g. communal oviposition). The published literature suggests that similar kinds of complex effects of clutch size on offspring viability are widespread in both vertebrates and invertebrates. Our results also challenge conventional experimental methodologies such as split-clutch designs for laboratory incubation studies: by separating an egg from its siblings, we may directly affect offspring size and thus viability.
Collapse
Affiliation(s)
- Gregory P Brown
- School of Biological Sciences A08, University of Sydney, Sydney, New South Wales 2006, Australia
| | | |
Collapse
|