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Kotilínek M, Těšitelová T, Košnar J, Fibich P, Hemrová L, Koutecký P, Münzbergová Z, Jersáková J. Seed dispersal and realized gene flow of two forest orchids in a fragmented landscape. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:522-532. [PMID: 32056355 DOI: 10.1111/plb.13099] [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: 11/21/2019] [Accepted: 02/01/2020] [Indexed: 06/10/2023]
Abstract
Species with vast production of dust-like windborne seeds, such as orchids, should not be limited by seed dispersal. This paradigm, however, does not fit recent studies showing that many sites suitable for orchids are unoccupied and most seeds land close to their maternal plant. To explore this issue, we studied seed dispersal and gene flow of two forest orchid species, Epipactis atrorubens and Cephalanthera rubra, growing in a fragmented landscape of forested limestone hills in southwest Bohemia, Czech Republic. We used a combination of seed trapping and plant genotyping methods (microsatellite DNA markers) to quantify short- and long-distance dispersal, respectively. In addition, seed production of both species was estimated. We found that most seeds landed very close to maternal plants (95% of captured seeds were within 7.2 m) in both species, and dispersal distance was influenced by forest type in E. atrorubens. In addition, C. rubra showed clonal reproduction (20% of plants were of clonal origin) and very low fruiting success (only 1.6% of plants were fruiting) in comparison with E. atrorubens (25.7%). Gene flow was frequent up to 2 km in C. rubra and up to 125 km in E. atrorubens, and we detected a relatively high dispersal rate among regions in both species. Although both species occupy similar habitats and have similar seed dispersal abilities, C. rubra is notably rarer in the study area. Considerably low fruiting success in this species likely limits its gene flow to longer distances and designates it more sensitive to habitat loss and fragmentation.
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Affiliation(s)
- M Kotilínek
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - T Těšitelová
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - J Košnar
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - P Fibich
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
- Institute of Botany, Czech Academy of Sciences, Průhonice, Czech Republic
| | - L Hemrová
- Institute of Botany, Czech Academy of Sciences, Průhonice, Czech Republic
| | - P Koutecký
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Z Münzbergová
- Institute of Botany, Czech Academy of Sciences, Průhonice, Czech Republic
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - J Jersáková
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
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da Silva JB, da Silva LB, Albuquerque UP, Castro CC. Bark and latex harvesting short-term impact on native tree species reproduction. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:744. [PMID: 30470920 DOI: 10.1007/s10661-018-7081-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 10/30/2018] [Indexed: 06/09/2023]
Abstract
The bark and the latex of plants constitute non-timber forest products (NTFPs) of medicinal and economic value that are widely harvested throughout the world. Bark and latex harvesting impacts on plant reproduction are controversial in the literature. Some species are negatively impacted, some do not show any response, and others may exhibit higher flower and fruit production after harvesting. In areas of rainforests and cerrado (tropical savanna) in northeastern Brazil, local people intensely remove the bark of Himatanthus drasticus (for latex collection) and Stryphnodendron rotundifolium for medicinal purposes. We aimed to investigate the short-term impact of harvesting upon reproductive effort of tree species, using those species as models. We assumed that bark harvesting negatively interferes in the reproductive capacity of plant species. Individuals of both species were harvested 2 months before blooming (treated) and the production of reproductive structures, physical characteristics of fruits and seeds, and the pre-emergent reproductive success were compared between treated and control (intact) individuals. All parameters of H. drasticus declined after bark removal, except pollen and ovule production. The only reproductive parameters of S. rotundifolium that were negatively affected were pollen and ovule production, and the pre-emergent reproductive success was higher in treatment individuals. We discuss the differences found between the species regarding responses to harvesting. Our results show that harvesting have short-term effects upon reproduction and may impair gene flow by affecting pollination and seed dispersal of tree species.
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Affiliation(s)
- Jacilene Bezerra da Silva
- Laboratório de Ecologia Reprodutiva de Angiospermas, Departamento de Biologia, Universidade Federal Rural de Pernambuco, Recife, Pernambuco State, Brazil
| | - Leonardo Barbosa da Silva
- Laboratório de Ecologia Reprodutiva de Angiospermas, Departamento de Biologia, Universidade Federal Rural de Pernambuco, Recife, Pernambuco State, Brazil
| | - Ulysses Paulino Albuquerque
- Laboratório de Ecologia e Evolução de Sistemas Socioecológicos, Centro de Biociências, Departamento de Botânica, Universidade Federal de Pernambuco, Recife, Pernambuco State, Brazil
| | - Cibele Cardoso Castro
- Laboratório de Ecologia Reprodutiva de Angiospermas, Departamento de Biologia, Universidade Federal Rural de Pernambuco, Recife, Pernambuco State, Brazil.
- Universidade Federal Rural de Pernambuco, Unidade Acadêmica de Garanhuns, Avenida Bom Pastor, s/n, Boa Vista, Garanhuns, Pernambuco State, 55292-272, Brazil.
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Moraes MA, Kubota TYK, Rossini BC, Marino CL, Freitas MLM, Moraes MLT, da Silva AM, Cambuim J, Sebbenn AM. Long-distance pollen and seed dispersal and inbreeding depression in Hymenaea stigonocarpa (Fabaceae: Caesalpinioideae) in the Brazilian savannah. Ecol Evol 2018; 8:7800-7816. [PMID: 30250664 PMCID: PMC6144967 DOI: 10.1002/ece3.4253] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 03/02/2018] [Accepted: 05/14/2018] [Indexed: 02/03/2023] Open
Abstract
Hymenaea stigonocarpa is a neotropical tree that is economically important due to its high-quality wood; however, because it has been exploited extensively, it is currently considered threatened. Microsatellite loci were used to investigate the pollen and seed dispersal, mating patterns, spatial genetic structure (SGS), genetic diversity, and inbreeding depression in H. stigonocarpa adults, juveniles, and open-pollinated seeds, which were sampled from isolated trees in a pasture and trees within a forest fragment in the Brazilian savannah. We found that the species presented a mixed mating system, with population and individual variations in the outcrossing rate (0.53-1.0). The studied populations were not genetically isolated due to pollen and seed flow between the studied populations and between the populations and individuals located outside of the study area. Pollen and seed dispersal occurred over long distances (>8 km); however, the dispersal patterns were isolated by distance, with a high frequency of mating occurring between near-neighbor trees and seeds dispersed near the parent trees. The correlated mating for individual seed trees was higher within than among fruits, indicating that fruits present a high proportion of full-sibs. Genetic diversity and SGS were similar among the populations, but offspring showed evidence of inbreeding, mainly originating from mating among related trees, which suggests inbreeding depression between the seed and adult stages. Selfing resulted in a higher inbreeding depression than mating among relatives, as assessed through survival and height. As the populations are not genetically isolated, both are important targets for in situ conservation to maintain their genetic diversity; for ex situ conservation, seeds can be collected from at least 78 trees in both populations separated by at least 250 m.
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Affiliation(s)
| | | | | | | | | | | | | | - Jose Cambuim
- Faculdade de Engenharia de Ilha Solteira/UNESPIlha SolteiraSPBrazil
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Ramos SLF, Dequigiovanni G, Sebbenn AM, Lopes MTG, Kageyama PY, de Macêdo JLV, Kirst M, Veasey EA. Spatial genetic structure, genetic diversity and pollen dispersal in a harvested population of Astrocaryum aculeatum in the Brazilian Amazon. BMC Genet 2016; 17:63. [PMID: 27108235 PMCID: PMC4842287 DOI: 10.1186/s12863-016-0371-8] [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: 11/26/2015] [Accepted: 04/15/2016] [Indexed: 11/13/2022] Open
Abstract
Background Astrocaryum aculeatum is a palm tree species native to the tropical regions of South America, exploited commercially by local farmers for the pulp extracted from its fruits. The objective of this research was to compare the genetic diversity between adult plants and seedlings from open-pollinated seeds, quantify the pollen flow and dispersal, the spatial genetic structure, and the effective size of a population that has been continuously harvested for its fruits. The study was carried out in a natural population of A. aculeatum distributed over approximately 8 ha in the State of Amazonas (Brazil), separated by 400 m from the closest neighboring population. In total, 112 potential pollen donors, 12 mother plants and 120 offspring were mapped and genotyped. Results Genetic diversity was high for parents and the offspring. The fixation indexes for adults (F = -0.035) and offspring (F = -0.060) were negative and not significant. A significant spatial genetic structure was detected for the adult plants (up to the distance of 45 m) indicating short-distance seed dispersal. Paternity analysis detected 9.2 % of pollen immigration and the average distance of pollination within the population was 81 m. The average effective pollination neighborhood area between plants was 1.51 ha. Conclusions Our results indicate that substantial introduction of new alleles has occurred in the population through pollen immigration, contributing to the maintenance of genetic diversity. Conservation efforts aimed at maintaining the gene pool of the current population or establishing new populations should utilize offspring from mother plants selected to be spaced by at least 50 m to prevent collecting seeds from relatives.
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Affiliation(s)
- Santiago Linorio Ferreyra Ramos
- Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo (ESALQ/USP), Departamento de Genética, C.P. 9, CEP 13418-900, Av. Pádua Dias, 11, Piracicaba, SP, Brazil.
| | - Gabriel Dequigiovanni
- Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo (ESALQ/USP), Departamento de Genética, C.P. 9, CEP 13418-900, Av. Pádua Dias, 11, Piracicaba, SP, Brazil
| | - Alexandre Magno Sebbenn
- Instituto Florestal de São Paulo, Seção de Melhoramento e Conservação Genética Florestal, C.P. 1322, CEP 01059-970, São Paulo, SP, Brazil
| | - Maria Teresa Gomes Lopes
- Faculdade de Ciências Agrárias, Universidade Federal do Amazonas (UFAM), CEP 60077-000, Manaus, AM, Brazil
| | - Paulo Yoshio Kageyama
- ESALQ/USP, Departamento de Ciências Florestais, Av. Pádua Dias, 11, C.P. 9, CEP 13418-900, Piracicaba, SP, Brazil
| | | | - Matias Kirst
- University of Florida, School of Forest Resources & Conservation, PO Box 110410, Gainesville, FL, 32611-0410, USA
| | - Elizabeth Ann Veasey
- Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo (ESALQ/USP), Departamento de Genética, C.P. 9, CEP 13418-900, Av. Pádua Dias, 11, Piracicaba, SP, Brazil.
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Gene flow and fine-scale spatial genetic structure in Cabralea canjerana (Meliaceae), a common tree species from the Brazilian Atlantic forest. JOURNAL OF TROPICAL ECOLOGY 2016. [DOI: 10.1017/s0266467416000067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Abstract:The Atlantic forest is the biome most severely affected by deforestation in Brazil. Cabralea canjerana spp. canjerana is a dioecious tree species with widespread distribution in the Neotropical region. This species is considered a model to ascertain population ecology parameters for endangered plant species from the Atlantic forest. Fine-scale spatial genetic structure and pollen-mediated gene flow are crucial information in landscape genetics and evolutionary ecology. A total of 192 adults and 121 offspring were sampled in seven C. canjerana populations in the Southern Minas Gerais State, Brazil, to assess whether pollen-mediated gene flow is able to prevent spatial genetic structure within and among Atlantic forest fragments. Several molecular ecology parameters were estimated using microsatellite loci. High levels of genetic diversity (HE = 0.732) and moderate population structure (θ = 0.133) were recorded. No significant association between kinship and spatial distance amongst individuals within each population (Sp = 0.000109) was detected. Current pollen-mediated gene flow occurs mainly within forest fragments, probably due to short-distance flights of the pollinator of C. canjerana, and also the forest fragmentation may have restricted flight distance. The high levels of genetic differentiation found amongst the seven sites sampled demonstrated how habitat fragmentation affects the gene flow process in natural areas.
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