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Binder M, Zinger E, Hadany L, Ohad N. Transgenerational effects of stress on reproduction strategy in the mixed mating plant Lamium amplexicaule. BMC PLANT BIOLOGY 2024; 24:794. [PMID: 39169281 PMCID: PMC11340105 DOI: 10.1186/s12870-024-05458-x] [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: 12/31/2023] [Accepted: 07/26/2024] [Indexed: 08/23/2024]
Abstract
BACKGROUND The theory of Condition Dependent Sex predicts that - everything else being equal - less fit individuals would outcross at higher rates compared with fitter ones. Here we used the mixed mating plant Lamium amplexicaule, capable of producing both self-pollinating closed flowers (CL), alongside open flowers (CH) that allow cross pollination to test it. We investigated the effects of abiotic stress - salt solution irrigation - on the flowering patterns of plants and their offspring. We monitored several flowering and vegetative parameters, including the number and distribution of flowers, CH fraction, and plant size. RESULTS We found that stressed plants show an increased tendency for self-pollination and a deficit in floral and vegetative development. However, when parentally primed, stressed plants show a milder response. Un-stressed offspring of stressed parents show reversed responses and exhibit an increased tendency to outcross, and improve floral and vegetative development. CONCLUSIONS In summary, we found that stress affects the reproduction strategy in the plants that experienced the stress and in subsequent offspring through F2 generation. Our results provide experimental evidence supporting a transgenerational extension to the theories of fitness associate sex and dispersal, where an individual's tendency for sex and dispersal may depend on the stress experienced by its parents.
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Affiliation(s)
- Mor Binder
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Eyal Zinger
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Lilach Hadany
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Nir Ohad
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv, 6997801, Israel.
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Stojanova B, Eliášová A, Tureček T. Competition and drought affect cleistogamy in a non-additive way in the annual ruderal Lamium amplexicaule. AOB PLANTS 2024; 16:plae036. [PMID: 38988683 PMCID: PMC11232460 DOI: 10.1093/aobpla/plae036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 06/21/2024] [Indexed: 07/12/2024]
Abstract
Competition affects mixed-mating strategies by limiting available abiotic or biotic resources such as nutrients, water, space, or pollinators. Cleistogamous species produce closed (cleistogamous, CL), obligately selfed, simultaneously with open (chasmogamous, CH), potentially outcrossed flowers. The effects of intraspecific competition on fitness and cleistogamy variation can range from limiting the production of costly CH flowers because of resource limitation, to favouring CH production because of fitness advantages of outcrossed, CH offspring. Moreover, the effects of competition can be altered when it co-occurs with other environmental variations. We grew plants from seven populations of the ruderal Lamium amplexicaule, originating from different climates and habitats, in a common garden experiment combining drought, interspecific competition, and seasonal variation. All these parameters have been shown to influence the degree of cleistogamy in the species on their own. In spring, competition and drought negatively impacted fitness, but the CL proportion only increased when plants were exposed to both treatments combined. We did not observe the same results in autumn, which can be due to non-adaptive phenotypic variation, or to differences in soil compactness between seasons. The observed responses are largely due to phenotypic plasticity, but we also observed phenotypic differentiation between populations for morphological, phenological, and cleistogamy traits, pointing to the existence of different ecotypes. Our data do not support the hypothesis that CL proportion should decrease when resources are scarce, as plants with reduced growth had relatively low CL proportions. We propose that variation in cleistogamy could be an adaptation to pollinator abundance, or to environment-dependent fitness differences between offspring of selfed and outcrossed seeds, two hypotheses worth further investigation. This opens exciting new possibilities for the study of the maintenance of mixed-mating systems using cleistogamous species as models that combine the effects of inbreeding and reproductive costs.
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Affiliation(s)
- Bojana Stojanova
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Chittussiho 10, 71000Czech Republic
- Department of Biology, University Federico II of Naples, Via Vicinale Cupa Cintia, 21, 80126 Naples, Italy
| | - Anežka Eliášová
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Chittussiho 10, 71000Czech Republic
| | - Tomáš Tureček
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Chittussiho 10, 71000Czech Republic
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Falik O, Hoffmann I, Novoplansky A. A novel type of neighbour perception elicits reproductive plasticity in an annual plant with a mixed mating system. PLANT BIOLOGY (STUTTGART, GERMANY) 2024; 26:415-420. [PMID: 38315483 DOI: 10.1111/plb.13624] [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: 11/19/2023] [Accepted: 01/17/2024] [Indexed: 02/07/2024]
Abstract
Plants display various forms of phenotypic plasticity in anticipation of changing conditions, many of which are influenced by information obtained from neighbouring plants. Here, we tested the hypothesis that cleistogamic Lamium amplexicaule plants can adaptively modify production of chasmogamous (CH) and cleistogamous (CL) flowers based on the perception of conspecific neighbours. The production and proportion of CH and CL flowers was examined in individual L. amplexicaule grown at varying densities or treated with root leachates from plants grown at different densities. When growing at high density or treated with root leachates from high-density pots, L. amplexicaule increased production of more expensive, potentially outcrossing CH flowers. In contrast, single plants or plants treated with root leachates from empty pots or single-source plants predominantly developed cheaper, self-pollinated CL flowers. The results demonstrate a novel root-based neighbour-perception modality that enables plants to adaptively adjust production of CH and CL flowers in response to the presence of potential reproductive partners. Further research is needed to explore the broader ecological implications of this novel interplant cueing on reproductive bet-hedging and plasticity in natural settings, as well as to identify the involved cues and their mode of operation.
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Affiliation(s)
- O Falik
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion, Israel
- Achva Academic College, Arugot, Israel
| | - I Hoffmann
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion, Israel
| | - A Novoplansky
- Mitrani Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion, Israel
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Soto TY, Rojas-Gutierrez JD, Oakley CG. Can heterosis and inbreeding depression explain the maintenance of outcrossing in a cleistogamous perennial? AMERICAN JOURNAL OF BOTANY 2023; 110:e16240. [PMID: 37672596 DOI: 10.1002/ajb2.16240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 09/08/2023]
Abstract
PREMISE What maintains mixed mating is an evolutionary enigma. Cleistogamy-the production of both potentially outcrossing chasmogamous and obligately selfing cleistogamous flowers on the same individual plant-is an excellent system to study the costs of selfing. Inbreeding depression can prevent the evolution of greater selfing within populations, and heterosis in crosses between populations may further tip the balance in favor of outcrossing. Few empirical estimates of inbreeding depression and heterosis in the same system exist for cleistogamous species. METHODS We investigate the potential costs of selfing by quantifying inbreeding depression and heterosis in three populations of the cleistogamous perennial Ruellia humilis Nutt (Acanthaceae). We performed three types of hand-pollinations-self, outcross-within, and outcross-between populations-and measured seed number, germination, total flower production, and estimated cumulative fitness for the resulting progeny in a greenhouse experiment. RESULTS We found moderate inbreeding depression for cumulative fitness (<30%) in two populations, but outbreeding depression for crosses within a third population (-26%). For between-population crosses, there was weak to modest heterosis (11-47%) in two of the population combinations, but modest to strong outbreeding depression (-21 to -71%) in the other four combinations. CONCLUSIONS Neither inbreeding depression nor heterosis was of sufficient magnitude to explain the continued production of chasmogamous flowers given the relative energetic advantage of cleistogamous flowers previously estimated for these populations. Outbreeding depression either within or between populations makes the maintenance of chasmogamous flowers even harder to explain. More information is needed on the genetic basis of cleistogamy to resolve this conundrum.
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Affiliation(s)
- Tatyana Y Soto
- Department of Botany and Plant Pathology and the Center for Plant Biology, Purdue University, West Lafayette, IN, USA
| | - Juan Diego Rojas-Gutierrez
- Department of Botany and Plant Pathology and the Center for Plant Biology, Purdue University, West Lafayette, IN, USA
| | - Christopher G Oakley
- Department of Botany and Plant Pathology and the Center for Plant Biology, Purdue University, West Lafayette, IN, USA
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Amer WM, Al Shaye NA, Hassan MO, Khalaf MH. Heteroblastic Inflorescence of Lamium amplexicaule L. in Egyptian Flora. PLANTS (BASEL, SWITZERLAND) 2023; 12:1028. [PMID: 36903891 PMCID: PMC10005391 DOI: 10.3390/plants12051028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 02/16/2023] [Accepted: 02/19/2023] [Indexed: 06/18/2023]
Abstract
Lamium amplexicaule L. (Family: Lamiaceae) is a cosmopolitan weed whose eradication is challenging. The phenoplasticity of this species is related to its heteroblastic inflorescence, which has not received adequate research worldwide in its morphological and genetic aspects. This inflorescence hosts two flower types, a cleistogamous (CL: closed flower) and a chasmogamous (CH: opened flower). This species subjected to detailed investigation is a model species to clarify: (1) the existence of the CL and CH flowers in relation to the time and individual plants. (2) the predominant flower morphs in Egypt. (3) the morphological and genetic variability between these morphs. Among the novel data retrieved from this work is the Presence of this species in three distinct morphs coexisting during winter. These morphs showed remarkable phenoplasticity, particularly in flower organs. Significant differences were observed between the three morphs in pollen fertility, nutlets productivity and sculpture, flowering time, and seed viability. These differences were extended to the genetic profile of these three morphs assessed by the inter simple sequence repeats (ISSRs) and start codon targeted (SCoT). This work highlights the urgent need to study the heteroblastic inflorescence of crop weeds to facilitate its eradication.
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Affiliation(s)
- Wafaa M. Amer
- Department of Botany and Microbiology, Faculty of Science, Cairo University, Giza 12613, Egypt
| | - Najla A. Al Shaye
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Mahmoud O. Hassan
- Department of Botany and Microbiology, Faculty of Science, Beni-Suef University, Beni-Suef 62521, Egypt
| | - Maha H. Khalaf
- Department of Botany and Microbiology, Faculty of Science, Beni-Suef University, Beni-Suef 62521, Egypt
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Li Q, Li K, Zhang Z, Li J, Wang B, Zhang Z, Zhu Y, Pan C, Sun K, He C. Transcriptomic comparison sheds new light on regulatory networks for dimorphic flower development in response to photoperiod in Viola prionantha. BMC PLANT BIOLOGY 2022; 22:336. [PMID: 35820812 PMCID: PMC9277944 DOI: 10.1186/s12870-022-03732-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/04/2022] [Indexed: 05/09/2023]
Abstract
BACKGROUND Chasmogamous (CH)-cleistogamous (CL) dimorphic flowers are developed in Viola prionantha. However, the environmental and genetic factors necessary for the CH-CL transition are unknown. RESULTS In the present work, short-day (SD) conditions induced CH flowers, whereas long days (LDs) triggered CL flowers in V. prionantha. Compared to fully developed CH flowers, CL flowers had less mature stamens, no nectar glands, and immature petals. Comparative transcriptomics revealed differentially expressed genes (DEGs) during CL and CH development. Core genes in the photoperiod pathway, such as V. prionantha orthologs of GIGANTEA (GI), CONSTANS (CO), and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), which promote floral induction, were highly expressed in CL flowers, whereas UNUSUAL FLORAL ORGANS (UFO) and B-class MADS-box genes for floral organ identity and development showed an opposite alteration. Moreover, genes in the glycolytic process, sucrose metabolic process, and fatty acid biosynthetic process were all highly expressed in CH flowers. Interestingly, V. prionantha orthologs of the B-class MADS-box genes APETALA3 (AP3) and PISTILLATA (PI) might relate to these sugar-fatty acid processes and were co-expressed with GAIP-B-like and YABBY5 (YAB5), which regulate the development of the petal, stamen, and nectary. Compared to CH flowers, DEGs and hub genes in the most significantly correlated modules of the gene co-expression network, which are involved in abiotic and biotic responses, were upregulated in CL flowers. CONCLUSIONS We proposed an integrative model for transcription regulation of genes in the photoperiod pathway, floral organ development, stress response, and sugar-fatty acid processes to determine CH-CL flower development in V. prionantha. Particularly, under LDs, activated GI may induce genes involved in the stress-response pathways, and then downregulated AP3 and PI or UFO to inhibit the sugar-fatty acid metabolic processes, together forming CL flowers. In contrast, CH flowers were produced under SDs. This work provides novel insights into the developmental evolution of dimorphic flowers in Viola.
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Affiliation(s)
- Qiaoxia Li
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China.
| | - Kunpeng Li
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhengrong Zhang
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China
| | - Jigang Li
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China
| | - Bo Wang
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China
| | - Zuoming Zhang
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China
| | - Yuanyuan Zhu
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China
| | - Chaochao Pan
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China
| | - Kun Sun
- Life Science College, Northwest Normal University, Anning East Road 967, Anning, Lanzhou, 730070, Gansu, China
| | - Chaoying He
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing, 100093, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China.
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Seguí J, Hervías-Parejo S, Traveset A. Selective forces on the maintenance of outcrossing in an almost exclusively cleistogamous violet species. AMERICAN JOURNAL OF BOTANY 2021; 108:2452-2463. [PMID: 34622956 DOI: 10.1002/ajb2.1768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 09/01/2021] [Indexed: 06/13/2023]
Abstract
PREMISE Cleistogamous species constitute interesting study systems to resolve the longstanding question of how outcrossing is maintained given that seed production is ensured through selfing. In this work, we investigate the selective forces that allow the persistence of producing self-pollinated cleistogamous (CL) and chasmogamous (CH) flowers in Viola jaubertiana Marès & Vigin. METHODS We monitored three populations at different elevation for two years, and studied the flowering phenology and the relative contribution of each flower morph to parental fitness. We tested whether allocation to CH and CL flowers differed across populations and if it covaried with herbivory and water stress conditions. We also performed hand-pollination and bagging experiments in CH flowers to estimate inbreeding depression and heterosis. RESULTS The CH flowers open in winter under unfavorable conditions for pollination, show high pollen limitation and no-delayed selfing, and thus produce a low amount of seeds. Conversely, CL flowers appear in early spring, are physiologically cheaper to produce (i.e., dry weight is 3.4 times lower than that of CH flowers), and yield approximately 100 times more seeds than CH flowers. The CH flowers were favored under water stress and low herbivory. Crosses between populations showed up to 25% greater fitness than those within populations. CONCLUSIONS Despite the great pollen limitation in CH flowers, we suggest that the interaction among different environmental determinants and heterosis are probably sufficient forces to maintain chasmogamy in this long-lived species, reducing deleterious fixed mutations in the selfed lines.
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Affiliation(s)
- Jaume Seguí
- Department of Global Change, Mediterranean Institute for Advanced Studies (CSIC-UIB), C/Miquel Marquès 21, 07190-Esporles, Mallorca, Balearic Islands, Spain
| | - Sandra Hervías-Parejo
- Department of Global Change, Mediterranean Institute for Advanced Studies (CSIC-UIB), C/Miquel Marquès 21, 07190-Esporles, Mallorca, Balearic Islands, Spain
| | - Anna Traveset
- Department of Global Change, Mediterranean Institute for Advanced Studies (CSIC-UIB), C/Miquel Marquès 21, 07190-Esporles, Mallorca, Balearic Islands, Spain
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Stojanova B, Maurice S, Cheptou PO. Season-dependent effect of cleistogamy in Lamium amplexicaule: flower type origin versus inbreeding status. AMERICAN JOURNAL OF BOTANY 2020; 107:155-163. [PMID: 31889300 DOI: 10.1002/ajb2.1410] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 11/14/2019] [Indexed: 06/10/2023]
Abstract
PREMISE Inbreeding depression is traditionally considered a major factor favoring outcrossing in hermaphrodites. Recent experiments have shown that environmental conditions can influence the magnitude of inbreeding depression, but their relevance in natural populations is unclear. To investigate this, we studied the cleistogamous species Lamium amplexicaule, an annual species with individuals experiencing either spring or autumn environmental conditions. In this species, the proportion of cleistogamous/chasmogamous flowers changes according to seasonal cues (e.g., temperature, photoperiod). Our hypothesis was that the plasticity of cleistogamy is an adaptation to seasonal fitness variation in different flower progenies. METHODS To test this hypothesis, we produced the three possible types of progenies through controlled crosses: (1) selfed progeny from cleistogamous flowers; (2) chasmogamous selfed progeny; and (3) chasmogamous outcrossed progeny. Progeny fitness was then measured in a common garden in the two reproduction seasons (autumn and spring). RESULTS The results showed that season had a major impact on fitness. The fitness of the different progeny types changed across seasons, indicating that the effect of cleistogamy on progeny performance is season-dependent, consistent with a previous study in a similar environment. Surprisingly, the flower from which the progeny issued (cleistogamous or chasmogamous) had more impact on fitness than the inbred status of the progeny (selfed versus outcrossed), suggesting a potential role of epigenetic processes. CONCLUSIONS The observed patterns of variation were not consistent either with adaptation to environment-dependent inbreeding depression or to variation in resource availability, but were possibly consistent with adaptation to seasonal pollinator activity.
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Affiliation(s)
- Bojana Stojanova
- Department of Biology and Ecology & Institute of Environmental Technologies, Faculty of Science, University of Ostrava, Chittussiho 10, 71000, Ostrava, Czech Republic
- ISEM, Université de Montpellier, CNRS, IRD, Montpellier, France
- CEFE, UMR 5175, CNRS, Université de Montpellier, Université Paul-Valery, Montpellier, EPHE - 1919 route de Mende, 34293, Montpellier cedex 05, France
| | | | - Pierre-Olivier Cheptou
- CEFE, UMR 5175, CNRS, Université de Montpellier, Université Paul-Valery, Montpellier, EPHE - 1919 route de Mende, 34293, Montpellier cedex 05, France
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Ansaldi BH, Weber JJ, Franks SJ. The role of phenotypic plasticity and pollination environment in the cleistogamous, mixed mating breeding system of Triodanis perfoliata. PLANT BIOLOGY (STUTTGART, GERMANY) 2018; 20:1068-1074. [PMID: 30028066 DOI: 10.1111/plb.12877] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 07/16/2018] [Indexed: 06/08/2023]
Abstract
The role of variable pollination environments in maintaining mixed mating systems is an active area of research. Dimorphic cleistogamy, in which a plant reproduces by both open, facultative outcrossing chasmogamous (CH) flowers and closed, cleistogamous (CL) flowers presents an excellent opportunity to study mixed mating. For example, plastic responses in allocation to an optimal floral type could serve as an adaptive strategy that maintains mixed mating under variable pollination environments. We tested for pollen limitation and plastic responses in allocation to different floral types under manipulated pollination conditions in the dimorphic cleistogamous, mixed mating annual, Triodanis perfoliata. Using a field population, we quantified pollen limitation, auto-fertility and plastic responses in the breeding system by measuring allocation to flower number and seed set of floral types. We found no evidence for pollen limitation for CH flowers, and CH flowers had low efficacy of autonomous selfing. Importantly, we found that T. perfoliata alters floral number following changes in pollination conditions, with pollen-supplemented plants having lower relative CH flower number than non-supplemented plants. Breeding system plasticity may allow for benefits from outcrossing through CH flowers, but also increased overall fitness through relatively cheap CL reproduction. After CH flowers receive pollen, subsequent production of CH flowers was reduced, which may be due to resource limitation. Our findings did not support a theoretical model predicting increased CH flowers with high pollination levels. These results increase our understanding of the role of pollination services and resource allocation in the maintenance of mixed mating systems, which also warrants further investigation.
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Affiliation(s)
- B H Ansaldi
- Department of Biology, Fordham University, Bronx, NY, USA
| | - J J Weber
- Department of Biology, Southeast Missouri State University, Cape Girardeau, NY, USA
| | - S J Franks
- Department of Biology, Fordham University, Bronx, NY, USA
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Anwar N, Ohta M, Yazawa T, Sato Y, Li C, Tagiri A, Sakuma M, Nussbaumer T, Bregitzer P, Pourkheirandish M, Wu J, Komatsuda T. miR172 downregulates the translation of cleistogamy 1 in barley. ANNALS OF BOTANY 2018; 122:251-265. [PMID: 29790929 PMCID: PMC6070043 DOI: 10.1093/aob/mcy058] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 04/30/2018] [Indexed: 05/04/2023]
Abstract
BACKGROUND AND AIMS Floret opening in barley is induced by the swelling of the lodicule, a trait under the control of the cleistogamy1 (cly1) gene. The product of cly1 is a member of the APETALA2 (AP2) transcription factor family, which inhibits lodicule development. A sequence polymorphism at the miR172 target site within cly1 has been associated with variation in lodicule development and hence with the cleistogamous phenotype. It was unclear whether miR172 actually functions in cly1 regulation and, if it does, which miR172 gene contributes to cleistogamy. It was also interesting to explore whether miR172-mediated cly1 regulation occurs at transcriptional level or at translational level. METHODS Deep sequencing of small RNA identified the miR172 sequences expressed in barley immature spikes. miR172 genes were confirmed by computational and expression analysis. miR172 and cly1 expression profiles were determined by in situ hybridization and quantitative expression analysis. Immunoblot analysis provided the CLY1 protein quantifications. Definitive evidence of the role of miR172 in cleistogamy was provided by a transposon Ds-induced mutant of Hv-miR172a. KEY RESULTS A small RNA analysis of the immature barley spike revealed three isomers, miR172a, b and c, of which miR172a was the most abundant. In situ hybridization analysis showed that miR172 and cly1 co-localize in the lodicule primordium, suggesting that these two molecules potentially interact with one another. Immunoblot analysis showed that the sequence polymorphism at the miR172 target site within cly1 reduced the abundance of the CLY1 protein, but not that of its transcript. In a Ds-induced mutant of Hv-miR172a, which generates no mature miR172a, the lodicules fail to grow, resulting in a very small lodicule. CONCLUSIONS Direct evidence is presented to show that miR172a acts to reduce the abundance of the CLY1 protein, which enables open flowering in barley.
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Affiliation(s)
- Nadia Anwar
- National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Masaru Ohta
- National Institute of Agrobiological Sciences, Tsukuba, Japan
- National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Takayuki Yazawa
- National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Yutaka Sato
- National Institute of Agrobiological Sciences, Tsukuba, Japan
- National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Chao Li
- National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Akemi Tagiri
- National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Mari Sakuma
- National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Thomas Nussbaumer
- Munich Information Center for Protein Sequences, Institute of Bioinformatics and Systems Biology, Helmholtz Center Munich, Neuherberg, Germany
- Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Phil Bregitzer
- USDA-ARS, National Small Grains Germplasm Research Facility, Aberdeen, ID, USA
| | - Mohammad Pourkheirandish
- National Institute of Agrobiological Sciences, Tsukuba, Japan
- National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
- The University of Sydney, Faculty of Agriculture and Environment, Plant Breeding Institute, Cobbitty, NSW, Australia
| | - Jianzhong Wu
- National Institute of Agrobiological Sciences, Tsukuba, Japan
- National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Takao Komatsuda
- National Institute of Agrobiological Sciences, Tsukuba, Japan
- National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
- For correspondence. E-mail
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Barnett LL, Troth A, Willis JH. Plastic breeding system response to day length in the California wildflower Mimulus douglasii. AMERICAN JOURNAL OF BOTANY 2018; 105:779-787. [PMID: 29693727 DOI: 10.1002/ajb2.1063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 01/11/2018] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Angiosperms have evolved multiple breeding systems that allow reproductive success under varied conditions. Striking among these are cleistogamous breeding systems, where individuals can produce alternative flower types specialized for distinct mating strategies. Cleistogamy is thought to be environmentally-dependent, but little is known about environmental triggers. If production of alternate flowers is environmentally induced, populations may evolve locally adapted responses. Mimulus douglasii, exhibits a cleistogamous breeding system, and ranges across temperature and day-length gradients, providing an ideal system to investigate environmental parameters that control cleistogamy. METHODS We compared flowering responses across Mimulus douglasii population accessions that produce distinct outcrossing and self-pollinating flower morphs. Under controlled conditions, we determined time to flower, and number and type of flowers produced under different temperatures and day lengths. KEY RESULTS Temperature and day length both affect onset of flowering. Long days shift flower type from predominantly chasmogamous to cleistogamous. The strength of the response to day length varies across accessions whether temperature varies or is held constant. CONCLUSIONS Cleistogamy is an environmentally sensitive polyphenism in Mimulus douglasii, allowing transition from one mating strategy to another. Longer days induce flowering and production of cleistogamous flowers. Shorter days induce chasmogamous flowers. Population origin has a small effect on response to environmental cues.
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Affiliation(s)
- Laryssa L Barnett
- Department of Biology, Duke University, Box 90338, Durham, North Carolina, 27708, USA
| | - Ashley Troth
- Department of Biology, Duke University, Box 90338, Durham, North Carolina, 27708, USA
| | - John H Willis
- Department of Biology, Duke University, Box 90338, Durham, North Carolina, 27708, USA
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