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Li C, Long Y, Lu M, Zhou J, Wang S, Xu Y, Tan X. Gene coexpression analysis reveals key pathways and hub genes related to late-acting self-incompatibility in Camellia oleifera. FRONTIERS IN PLANT SCIENCE 2023; 13:1065872. [PMID: 36762174 PMCID: PMC9902722 DOI: 10.3389/fpls.2022.1065872] [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: 10/10/2022] [Accepted: 12/29/2022] [Indexed: 06/18/2023]
Abstract
INTRODUCTION Self-incompatibility (SI) is an important strategy for plants to maintain abundant variation to enhance their adaptability to the environment. Camellia oleifera is one of the most important woody oil plants and is widely cultivated in China. Late acting self-incompatibility (LSI) in C. oleifera results in a relatively poor fruit yield in the natural state, and understanding of the LSI mechanism remains limited. METHODS To better understand the molecular expression and gene coexpression network in the LSI reaction in C. oleifera, we conducted self- and cross-pollination experiments at two different flower bud developmental stages (3-4 d before flowering and 1 d before flowering), and cytological observation, fruit setting rate (FSR) investigation and RNA-Seq analysis were performed to investigate the mechanism of the male -female interaction and identify hub genes responsible for the LSI in C. oleifera. RESULTS Based on the 21 ovary transcriptomes, a total of 7669 DEGs were identified after filtering out low-expression genes. Weighted gene coexpression network analysis (WGCNA) divided the DEGs into 15 modules. Genes in the blue module (1163 genes) were positively correlated with FSR, and genes in the pink module (339 genes) were negatively correlated with FSR. KEGG analysis indicated that flavonoid biosynthesis, plant MAPK signaling pathways, ubiquitin-mediated proteolysis, and plant-pathogen interaction were the crucial pathways for the LSI reaction. Fifty four transcription factors (TFs) were obtained in the two key modules, and WRKY and MYB were potentially involved in the LSI reaction in C. oleifera. Network establishment indicated that genes encoding G-type lectin S-receptor-like serine (lecRLK), isoflavone 3'-hydroxylase-like (CYP81Q32), cytochrome P450 87A3-like (CYP87A3), and probable calcium-binding protein (CML41) were the hub genes that positively responded to the LSI reaction. The other DEGs inside the two modules, including protein RALF-like 10 (RALF), F-box and pectin acetylesterase (MTERF5), might also play vital roles in the LSI reaction in C. oleifera. DISCUSSION Overall, our study provides a meaningful resource for gene network studies of the LSI reaction process and subsequent analyses of pollen-pistil interactions and TF roles in the LSI reaction, and it also provides new insights for exploring the mechanisms of the LSI response.
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Affiliation(s)
- Chang Li
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Academy of Camellia Oil Tree, Central South University of Forestry and Technology, Changsha, China
| | - Yi Long
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Academy of Camellia Oil Tree, Central South University of Forestry and Technology, Changsha, China
| | - Mengqi Lu
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Academy of Camellia Oil Tree, Central South University of Forestry and Technology, Changsha, China
| | - Junqin Zhou
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Academy of Camellia Oil Tree, Central South University of Forestry and Technology, Changsha, China
| | - Sen Wang
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- The Belt and Road International Union Research Center for Tropical Arid Non-wood Forest in Hunan Province, Changsha, China
| | - Yan Xu
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Academy of Camellia Oil Tree, Central South University of Forestry and Technology, Changsha, China
| | - Xiaofeng Tan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Academy of Camellia Oil Tree, Central South University of Forestry and Technology, Changsha, China
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Lubini G, Ferreira PB, Quiapim AC, Brito MS, Cossalter V, Pranchevicius MCS, Goldman MHS. Silencing of a Pectin Acetylesterase (PAE) Gene Highly Expressed in Tobacco Pistils Negatively Affects Pollen Tube Growth. PLANTS (BASEL, SWITZERLAND) 2023; 12:329. [PMID: 36679042 PMCID: PMC9864977 DOI: 10.3390/plants12020329] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/06/2023] [Accepted: 01/07/2023] [Indexed: 06/17/2023]
Abstract
Successful plant reproduction and fruit formation depend on adequate pollen and pistil development, and pollen-pistil interactions. In Nicotiana tabacum, pollen tubes grow through the intercellular spaces of pistil-specialized tissues, stigmatic secretory zone, and stylar transmitting tissue (STT). These intercellular spaces are supposed to be formed by the modulation of cell wall pectin esterification. Previously we have identified a gene preferentially expressed in pistils encoding a putative pectin acetylesterase (PAE), named NtPAE1. Here, we characterized the NtPAE1 gene and performed genome-wide and phylogenetic analyses of PAEs. We identified 30 PAE sequences in the N. tabacum genome, distributed in four clades. The expression of NtPAE1 was assessed by RT-qPCR and in situ hybridization. We confirmed NtPAE1 preferential expression in stigmas/styles and ovaries and demonstrated its high expression in the STT. Structural predictions and comparisons between NtPAE1 and functional enzymes validated its identity as a PAE. Transgenic plants were produced, overexpressing and silencing the NtPAE1 gene. Overexpressed plants displayed smaller flowers while silencing plants exhibited collapsed pollen grains, which hardly germinate. NtPAE1 silencing plants do not produce fruits, due to impaired pollen tube growth in their STTs. Thus, NtPAE1 is an essential enzyme regulating pectin modifications in flowers and, ultimately, in plant reproduction.
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Affiliation(s)
- Greice Lubini
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
| | - Pedro Boscariol Ferreira
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
- PPG-Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14049-900, SP, Brazil
| | - Andréa Carla Quiapim
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
| | - Michael Santos Brito
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
| | - Viviane Cossalter
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
| | | | - Maria Helena S. Goldman
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
- PPG-Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14049-900, SP, Brazil
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Mayer JLS, Scopece G, Barone Lumaga MR, Coiro M, Pinheiro F, Cozzolino S. Ecological and phylogenetic constraints determine the stage of anthetic ovule development in orchids. AMERICAN JOURNAL OF BOTANY 2021; 108:2405-2415. [PMID: 34622937 DOI: 10.1002/ajb2.1770] [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: 01/03/2021] [Revised: 09/06/2021] [Accepted: 09/07/2021] [Indexed: 06/13/2023]
Abstract
PREMISE Unlike most flowering plants, orchid flowers have under-developed ovules that complete development only after pollination. Classical studies reported variation in the stage in which ovule development is arrested, but the extent of this variation and its evolutionary and ecological significance are unclear. METHODS Here, we used light microscopy to observe ovule development at anthesis for 39 species not previously studied and surveyed the literature gaining information on 94 orchid species. Tropical and temperate members of all five orchid subfamilies as well as species with contrasting pollination strategies (rewarding versus deceptive) and life forms (epiphytic versus terrestrial) were represented. We analyzed the data using statistical comparisons and a phylogenetic generalized least square (PGLS) analysis. RESULTS Apostasioideae, the sister to the rest of the orchids, have mature ovules similar to other Asparagales, while under-differentiated ovules are present in the other subfamilies. Ovule developmental stages showed high variation even among closely related groups. Ovules were more developed in terrestrial than in epiphytic, in temperate than in tropical, and in rewarding than in deceptive pollination orchid species. This latter comparison was also significant in the PGLS analysis. CONCLUSIONS These results suggest that ovule developmental stage in orchids can be shaped by ecological factors, such as seasonality and pollination strategy, and can be selected for optimizing female reproductive investment.
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Affiliation(s)
- Juliana Lischka Sampaio Mayer
- Department of Plant Biology, Institute of Biology, State University of Campinas - UNICAMP - 13083-862, Campinas, SP, Brazil
| | - Giovanni Scopece
- Department of Biology, University of Naples Federico II, Naples, Italy
| | | | - Mario Coiro
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Fabio Pinheiro
- Department of Plant Biology, Institute of Biology, State University of Campinas - UNICAMP - 13083-862, Campinas, SP, Brazil
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Barone Lumaga MR, Scopece G, Cozzolino S. The effect of seasonality on developmental stages of anthetic ovule integuments in Mediterranean orchids. PROTOPLASMA 2020; 257:613-618. [PMID: 31832777 DOI: 10.1007/s00709-019-01464-1] [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: 09/13/2019] [Accepted: 11/22/2019] [Indexed: 06/10/2023]
Abstract
Orchids, differently from most flowering plants, have under-differentiated ovules at anthesis that require pollination to complete differentiation. This ovule developmental stage has been often observed in tropical species in which the absence of an evident seasonality may allow plants to extend their phenology beneficiating of a long time for post-pollination events. Here, we used scanning electron microscopy (SEM) to detect ovule integument developmental stages in 21 species of Mediterranean Orchidoideae and Epidendroideae and in 11 tropical Epidendroideae with the aim of understanding whether species with a seasonal constraint and shorter time for post-pollination ovule maturation are characterized by different stages of ovule development at anthesis. We found that Mediterranean orchids (both Orchidoideae and Epidendroideae) have more developed ovule integuments than tropical orchids. Most species show partially to fully developed ovules at anthesis with the exception of Cephalanthera where ovules are arrested in a very early developmental stage. Despite the phylogenetic signal, anthetic ovule integument development differs between related species (with different pollination strategies or blooming times), suggesting the presence of some ecological constraints. The synchronization between ovule integuments and megagametophyte development, as found in tropical orchids, is also confirmed in Mediterranean orchids. Our data show that Mediterranean and tropical orchids clearly differ in anthetic ovule developmental stages, likely depending on seasonality.
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Affiliation(s)
- Maria Rosaria Barone Lumaga
- Department of Biology, Complesso Universitario MSA, University of Naples Federico II, via Cinthia, I-80126, Naples, Italy
| | - Giovanni Scopece
- Department of Biology, Complesso Universitario MSA, University of Naples Federico II, via Cinthia, I-80126, Naples, Italy.
| | - Salvatore Cozzolino
- Department of Biology, Complesso Universitario MSA, University of Naples Federico II, via Cinthia, I-80126, Naples, Italy
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Joly V, Tebbji F, Nantel A, Matton DP. Pollination Type Recognition from a Distance by the Ovary Is Revealed Through a Global Transcriptomic Analysis. PLANTS (BASEL, SWITZERLAND) 2019; 8:E185. [PMID: 31238522 PMCID: PMC6630372 DOI: 10.3390/plants8060185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/09/2019] [Accepted: 06/12/2019] [Indexed: 02/06/2023]
Abstract
Sexual reproduction in flowering plants involves intimate contact and continuous interactions between the growing pollen tube and the female reproductive structures. These interactions can trigger responses in distal regions of the flower well ahead of fertilization. While pollination-induced petal senescence has been studied extensively, less is known about how pollination is perceived at a distance in the ovary, and how specific this response is to various pollen genotypes. To address this question, we performed a global transcriptomic analysis in the ovary of a wild potato species, Solanum chacoense, at various time points following compatible, incompatible, and heterospecific pollinations. In all cases, pollen tube penetration in the stigma was initially perceived as a wounding aggression. Then, as the pollen tubes grew in the style, a growing number of genes became specific to each pollen genotype. Functional classification analyses revealed sharp differences in the response to compatible and heterospecific pollinations. For instance, the former induced reactive oxygen species (ROS)-related genes while the latter affected genes associated to ethylene signaling. In contrast, incompatible pollination remained more akin to a wound response. Our analysis reveals that every pollination type produces a specific molecular signature generating diversified and specific responses at a distance in the ovary in preparation for fertilization.
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Affiliation(s)
- Valentin Joly
- Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, QC H1X 2B2, Canada.
| | - Faïza Tebbji
- CRCHU de Québec, Université Laval, Québec, QC G1V 4G2, Canada.
| | - André Nantel
- National Research Council Canada, Montréal, QC H4P 2R2, Canada.
| | - Daniel P Matton
- Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, QC H1X 2B2, Canada.
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Abbas HMK, Xiang J, Ahmad Z, Wang L, Dong W. Enhanced Nicotiana benthamiana immune responses caused by heterologous plant genes from Pinellia ternata. BMC PLANT BIOLOGY 2018; 18:357. [PMID: 30558544 PMCID: PMC6296014 DOI: 10.1186/s12870-018-1598-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 12/10/2018] [Indexed: 05/03/2023]
Abstract
BACKGROUND Pinellia ternata is a Chinese traditional medicinal herb, used to cure diseases including insomnia, eclampsia and cervical carcinoma, for hundreds of years. Non-self-recognition in multicellular organisms can initiate the innate immunity to avoid the invasion of pathogens. A design for pathogen independent, heterosis based, fresh resistance can be generated in F1 hybrid was proposed. RESULTS By library functional screening, we found that P. ternata genes, named as ptHR375 and ptHR941, were identified with the potential to trigger a hypersensitive response in Nicotiana benthamiana. Significant induction of ROS and Callose deposition in N. benthamiana leaves along with activation of pathogenesis-related genes viz.; PR-1a, PR-5, PDF1.2, NPR1, PAL, RBOHB and ERF1 and antioxidant enzymes was observed. After transformation into N. benthamiana, expression of pathogenesis related genes was significantly up-regulated to generate high level of resistance against Phytophthora capsici without affecting the normal seed germination and morphological characters of the transformed N. benthamiana. UPLC-QTOF-MS analysis of ptHR375 transformed N. benthamiana revealed the induction of Oxytetracycline, Cuelure, Allantoin, Diethylstilbestrol and 1,2-Benzisothiazol-3(2H)-one as bioactive compounds. Here we also proved that F1 hybrids, produced by crossing of the ptHR375 and ptHR941 transformed and non-transformed N. benthamiana, show significant high levels of PR-gene expressions and pathogen resistance. CONCLUSIONS Heterologous plant genes can activate disease resistance in another plant species and furthermore, by generating F1 hybrids, fresh pathogen independent plant immunity can be obtained. It is also concluded that ptHR375 and ptHR941 play their role in SA and JA/ET defense pathways to activate the resistance against invading pathogens.
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Affiliation(s)
- Hafiz Muhammad Khalid Abbas
- Department of Plant Pathology, College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Jingshu Xiang
- Department of Plant Pathology, College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Zahoor Ahmad
- Department of Plant Pathology, College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Lilin Wang
- Department of Plant Pathology, College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Wubei Dong
- Department of Plant Pathology, College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China.
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Brito MS, DePaoli HC, Cossalter V, Avanci NC, Ferreira PB, Azevedo MS, Strini EJ, Quiapim AC, Goldman GH, Peres LEP, Goldman MHS. A novel cysteine-rich peptide regulates cell expansion in the tobacco pistil and influences its final size. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 277:55-67. [PMID: 30466601 DOI: 10.1016/j.plantsci.2018.09.002] [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: 07/14/2018] [Revised: 09/01/2018] [Accepted: 09/04/2018] [Indexed: 06/09/2023]
Abstract
Plant morphogenesis is dependent on cell proliferation and cell expansion, which are responsible for establishing final organ size and shape during development. Several genes have been described as encoding components of the plant cell development machinery, among which are the plant peptides. Here we describe a novel cysteine-rich plant peptide (68 amino acids), encoded by a small open reading frame gene (sORF). It is specifically expressed in the reproductive organs of Nicotiana tabacum and is developmentally regulated. N- and C-terminal translational fusions with GFP in protoplasts have demonstrated that the peptide is not secreted. Knockdown transgenic plants produced by RNAi exhibited enlarged pistils due to cell expansion and the gene was named Small Peptide Inhibitor of Cell Expansion (SPICE). Estimation of nuclear DNA content using flow cytometry has shown that cell expansion in pistils was not correlated with endoreduplication. Decreased SPICE expression also affected anther growth and pollen formation, resulting in male sterility in at least one transgenic plant. Our results revealed that SPICE is a novel reproductive organ specific gene that controls cell expansion, probably as a component of a signal transduction pathway.
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Affiliation(s)
- Michael S Brito
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil; PPG - Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900, Brazil.
| | - Henrique C DePaoli
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil; PPG - Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900, Brazil
| | - Viviani Cossalter
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil; PPG - Biologia Comparada, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil
| | - Nilton C Avanci
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil; PPG - Biologia Comparada, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil
| | - Pedro B Ferreira
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil; PPG - Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900, Brazil
| | | | - Edward J Strini
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil; PPG - Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900, Brazil
| | - Andréa C Quiapim
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil
| | - Gustavo H Goldman
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, 14040-903, Brazil
| | - Lázaro E P Peres
- Departamento de Ciências Biológicas, Escola Superior de Agricultura Luiz de Queiroz Universidade de São Paulo, 13418-900, Brazil
| | - Maria Helena S Goldman
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Brazil.
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Yardeni G, Tessler N, Imbert E, Sapir Y. Reproductive isolation between populations of Iris atropurpurea is associated with ecological differentiation. ANNALS OF BOTANY 2016; 118:971-982. [PMID: 27436798 PMCID: PMC5055820 DOI: 10.1093/aob/mcw139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 05/13/2016] [Accepted: 05/23/2016] [Indexed: 05/28/2023]
Abstract
Background and Aims Speciation is often described as a continuous dynamic process, expressed by different magnitudes of reproductive isolation (RI) among groups in different levels of divergence. Studying intraspecific partial RI can shed light on mechanisms underlying processes of population divergence. Intraspecific divergence can be driven by spatially stochastic accumulation of genetic differences following reduced gene flow, resulting in increased RI with increased geographical distance, or by local adaptation, resulting in increased RI with environmental difference. Methods We tested for RI as a function of both geographical distance and ecological differentiation in Iris atropurpurea, an endemic Israeli coastal plant. We crossed plants in the Netanya Iris Reserve population with plants from 14 populations across the species' full distribution, and calculated RI and reproductive success based on fruit set, seed set and fraction of seed viability. Key Results We found that total RI was not significantly associated with geographical distance, but significantly increased with ecological distance. Similarly, reproductive success of the crosses, estimated while controlling for the dependency of each component on the previous stage, significantly reduced with increased ecological distance. Conclusions Our results indicate that the rise of post-pollination reproductive barriers in I. atropurpurea is more affected by ecological differentiation between populations than by geographical distance, supporting the hypothesis that ecological differentiation is predominant over isolation by distance and by reduced gene flow in this species. These findings also affect conservation management, such as genetic rescue, in the highly fragmented and endangered I. atropurpurea.
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Affiliation(s)
- Gil Yardeni
- The Botanical Garden, Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
| | - Naama Tessler
- Department of Biology, University of Haifa, Oranim, Tivon, Israel
| | - Eric Imbert
- Institut des Sciences de l’Evolution CNRS, IRD, University Montpellier 2, Montpellier, France
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