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Travers SE, Bishop DB, Sagers CL. Persistence of genetically engineered canola populations in the U.S. and the adventitious presence of transgenes in the environment. PLoS One 2024; 19:e0295489. [PMID: 38776262 PMCID: PMC11111013 DOI: 10.1371/journal.pone.0295489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 04/17/2024] [Indexed: 05/24/2024] Open
Abstract
Feralization of genetically engineered (GE) crops increases the risk that transgenes will become integrated into natural and naturalizing plant populations. A key assumption of the management of GE crops is that populations of escaped plants are short-lived and therefore the risks they pose are limited. However, few populations of escaped crop plants have been tracked over the long term so our understanding of their persistence in ruderal or natural landscapes is limited. We repeated a large-scale road survey of feral GE canola populations in North Dakota, USA, initially conducted in 2010. Our objectives in 2021 were to determine the current distribution of feral canola populations, and to establish the relative frequency of GE and non-GE phenotypes in populations of canola throughout North Dakota. Our results indicate that, although the incidence of feral canola was less in 2021 than 2010, escaped canola populations remain common throughout the state. The prevalence of alternate forms of GE herbicide resistance changed between surveys, and we found an overabundance of non-GE plants compared to the frequency of non-transgenic forms in cultivation. Indirect evidence of persistence includes sampling plants with multiple transgenic traits, and finding populations far from transportation routes. We conclude that feral canola populations expressing transgenic herbicide resistance are established outside of cultivation, that they may be under selection for loss of the transgene, but that they nonetheless pose long-term risks by harboring transgenes in the unmanaged landscape.
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Affiliation(s)
- Steven E. Travers
- Department of Biological Sciences, North Dakota State University, Fargo, North Dakota, United States of America
| | - D. Bryan Bishop
- Department of Biology, Concordia College, Morehead, Minnesota, United States of America
| | - Cynthia L. Sagers
- College of Integrated Sciences and Arts, Arizona State University, Tempe, Arizona, United States of America
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2
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Hernández F, Palmieri L, Brunet J. Introgression and persistence of cultivar alleles in wild carrot (Daucus carota) populations in the United States. AMERICAN JOURNAL OF BOTANY 2023; 110:e16242. [PMID: 37681637 DOI: 10.1002/ajb2.16242] [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: 05/01/2023] [Revised: 09/06/2023] [Accepted: 09/06/2023] [Indexed: 09/09/2023]
Abstract
PREMISE Cultivated species and their wild relatives often hybridize in the wild, and the hybrids can survive and reproduce in some environments. However, it is unclear whether cultivar alleles are permanently incorporated into the wild genomes or whether they are purged by natural selection. This question is key to accurately assessing the risk of escape and spread of cultivar genes into wild populations. METHODS We used genomic data and population genomic methods to study hybridization and introgression between cultivated and wild carrot (Daucus carota) in the United States. We used single nucleotide polymorphisms (SNPs) obtained via genotyping by sequencing for 450 wild individuals from 29 wild georeferenced populations in seven states and 144 cultivars from the United States, Europe, and Asia. RESULTS Cultivated and wild carrot formed two genetically differentiated groups, and evidence of crop-wild admixture was detected in several but not all wild carrot populations in the United States. Two regions were identified where cultivar alleles were present in wild carrots: California and Nantucket Island (Massachusetts). Surprisingly, there was no evidence of introgression in some populations with a long-known history of sympatry with the crop, suggesting that post-hybridization barriers might prevent introgression in some areas. CONCLUSIONS Our results provide support for the introgression and long-term persistence of cultivar alleles in wild carrots populations. We thus anticipate that the release of genetically engineered (GE) cultivars would lead to the introduction and spread of GE alleles in wild carrot populations.
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Affiliation(s)
- Fernando Hernández
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés 800, 8000, Bahía Blanca, Argentina
- CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Camino La Carrindanga Km 7, 8000, Bahía Blanca, Argentina
- Department of Botany and Biodiversity Research Centre, University of British Columbia, 2212 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Luciano Palmieri
- Agricultural Research Service Research Participation Program, Oak Ridge Institute for Science and Education (ORISE), Madison, WI, USA
| | - Johanne Brunet
- Vegetable Crops Research Unit, USDA-ARS, Madison, WI, USA
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3
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Vercellino RB, Hernández F, Presotto A. The role of intraspecific crop-weed hybridization in the evolution of weediness and invasiveness: Cultivated and weedy radish (Raphanus sativus) as a case study. AMERICAN JOURNAL OF BOTANY 2023; 110:e16217. [PMID: 37659092 DOI: 10.1002/ajb2.16217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/26/2023] [Accepted: 05/30/2023] [Indexed: 09/04/2023]
Abstract
PREMISE The phenotype of hybrids between a crop and its wild or weed counterpart is usually intermediate and maladapted compared to that of their parents; however, hybridization has sometimes been associated with increased fitness, potentially leading to enhanced weediness and invasiveness. Since the ecological context and maternal genetic effects may affect hybrid fitness, they could influence the evolutionary outcomes of hybridization. Here, we evaluated the performance of first-generation crop-weed hybrids of Raphanus sativus and their parents in two contrasting ecological conditions. METHODS Using experimental hybridization and outdoor common garden experiments, we assessed differences in time to flowering, survival to maturity, plant biomass, and reproductive components between bidirectional crop-weed hybrids and their parents in agrestal (wheat cultivation, fertilization, weeding) and ruderal (human-disturbed, uncultivated area) conditions over 2 years. RESULTS Crop, weeds, and bidirectional hybrids overlapped at least partially during the flowering period, indicating a high probability of gene flow. Hybrids survived to maturity at rates at least as successful as their parents and had higher plant biomass and fecundity, which resulted in higher fitness compared to their parents in both environments, without any differences associated with the direction of the hybridization. CONCLUSIONS Intraspecific crop-weed hybridization, regardless of the cross direction, has the potential to promote weediness in weedy R. sativus in agrestal and ruderal environments, increasing the chances for introgression of crop alleles into weed populations. This is the first report of intraspecific crop-weed hybridization in R. sativus.
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Affiliation(s)
- Román B Vercellino
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, San Andrés 800, Bahía Blanca, 8000, Argentina
| | - Fernando Hernández
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, San Andrés 800, Bahía Blanca, 8000, Argentina
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alejandro Presotto
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, San Andrés 800, Bahía Blanca, 8000, Argentina
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Dominguez-Valenzuela JA, Palma-Bautista C, Vazquez-Garcia JG, Yanniccari M, Gigón R, Alcántara-de la Cruz R, De Prado R, Portugal J. Convergent Adaptation of Multiple Herbicide Resistance to Auxin Mimics and ALS- and EPSPS-Inhibitors in Brassica rapa from North and South America. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12112119. [PMID: 37299097 DOI: 10.3390/plants12112119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/23/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023]
Abstract
Herbicide-resistant weeds have been identified and recorded on every continent where croplands are available. Despite the diversity of weed communities, it is of interest how selection has led to the same consequences in distant regions. Brassica rapa is a widespread naturalized weed that is found throughout temperate North and South America, and it is a frequent weed among winter cereal crops in Argentina and in Mexico. Broadleaf weed control is based on glyphosate that is used prior to sowing and sulfonylureas or mimic auxin herbicides that are used once the weeds have already emerged. This study was aimed at determining whether a convergent phenotypic adaptation to multiple herbicides had occurred in B. rapa populations from Mexico and Argentina by comparing the herbicide sensitivity to inhibitors of the acetolactate synthase (ALS), 5-enolpyruvylshikimate-3-phosphate (EPSPS), and auxin mimics. Five B. rapa populations were analyzed from seeds collected in wheat fields in Argentina (Ar1 and Ar2) and barley fields in Mexico (Mx1, Mx2 and MxS). Mx1, Mx2, and Ar1 populations presented multiple resistance to ALS- and EPSPS-inhibitors and to auxin mimics (2,4-D, MCPA, and fluroxypyr), while the Ar2 population showed resistance only to ALS-inhibitors and glyphosate. Resistance factors ranged from 947 to 4069 for tribenuron-methyl, from 1.5 to 9.4 for 2,4-D, and from 2.7 to 42 for glyphosate. These were consistent with ALS activity, ethylene production, and shikimate accumulation analyses in response to tribenuron-methyl, 2,4-D, and glyphosate, respectively. These results fully support the evolution of the multiple- and cross-herbicide resistance to glyphosate, ALS-inhibitors, and auxinic herbicides in B. rapa populations from Mexico and Argentina.
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Affiliation(s)
| | - Candelario Palma-Bautista
- Department Agroforestry, Biochemistry and Molecular Biology, University of Cordoba, 14014 Cordoba, Spain
| | - José G Vazquez-Garcia
- Department Agroforestry, Biochemistry and Molecular Biology, University of Cordoba, 14014 Cordoba, Spain
| | - Marcos Yanniccari
- Chacra Experimental Integrada Barrow (MDA-INTA), National Scientific and Technical Research Council (CONICET), Faculty of Agronomy, National University of La Pampa, Santa Rosa L6300, Argentina
| | - Ramón Gigón
- Private Consultant in Weed Control, Buenos Aires C1033, Argentina
| | | | - Rafael De Prado
- Department Agroforestry, Biochemistry and Molecular Biology, University of Cordoba, 14014 Cordoba, Spain
| | - João Portugal
- Biosciences Department, Polytechnic Institute of Beja, 7800-000 Beja, Portugal
- VALORIZA-Research Centre for Endogenous Resource Valorization, Polytechnic Institute of Portalegre, 7300-555 Portalegre, Portugal
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Cai XX, Wang Z, Yuan Y, Pang LH, Wang Y, Lu BR. Crop-Weed Introgression Plays Critical Roles in Genetic Differentiation and Diversity of Weedy Rice: A Case Study of Human-Influenced Weed Evolution. BIOLOGY 2023; 12:biology12050744. [PMID: 37237556 DOI: 10.3390/biology12050744] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023]
Abstract
As an important driving force, introgression plays an essential role in shaping the evolution of plant species. However, knowledge concerning how introgression affects plant evolution in agroecosystems with strong human influences is still limited. To generate such knowledge, we used InDel (insertion/deletion) molecular fingerprints to determine the level of introgression from japonica rice cultivars into the indica type of weedy rice. We also analyzed the impact of crop-to-weed introgression on the genetic differentiation and diversity of weedy rice, using InDel (insertion/deletion) and SSR (simple sequence repeat) molecular fingerprints. Results based on the STRUCTURE analysis indicated an evident admixture of some weedy rice samples with indica and japonica components, suggesting different levels of introgression from japonica rice cultivars to the indica type of weedy rice. The principal coordinate analyses indicated indica-japonica genetic differentiation among weedy rice samples, which was positively correlated with the introgression of japonica-specific alleles from the rice cultivars. In addition, increased crop-to-weed introgression formed a parabola pattern of dynamic genetic diversity in weedy rice. Our findings based on this case study provide evidence that human activities, such as the frequent change in crop varieties, can strongly influence weed evolution by altering genetic differentiation and genetic diversity through crop-weed introgression in agroecosystems.
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Affiliation(s)
- Xing-Xing Cai
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Zhi Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Ye Yuan
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Li-Hao Pang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Ying Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Bao-Rong Lu
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
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Vercellino RB, Hernández F, Pandolfo C, Ureta S, Presotto A. Agricultural weeds: the contribution of domesticated species to the origin and evolution of feral weeds. PEST MANAGEMENT SCIENCE 2023; 79:922-934. [PMID: 36507604 DOI: 10.1002/ps.7321] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/04/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Agricultural weeds descended from domesticated ancestors, directly from crops (endoferality) and/or from crop-wild hybridization (exoferality), may have evolutionary advantages by rapidly acquiring traits pre-adapted to agricultural habitats. Understanding the role of crops on the origin and evolution of agricultural weeds is essential to develop more effective weed management programs, minimize crop losses due to weeds, and accurately assess the risks of cultivated genes escaping. In this review, we first describe relevant traits of weediness: shattering, seed dormancy, branching, early flowering and rapid growth, and their role in the feralization process. Furthermore, we discuss how the design of "super-crops" can affect weed evolution. We then searched for literature documenting cases of agricultural weeds descended from well-domesticated crops, and describe six case studies of feral weeds evolved from major crops: maize, radish, rapeseed, rice, sorghum, and sunflower. Further studies on the origin and evolution of feral weeds can improve our understanding of the physiological and genetic mechanisms underpinning the adaptation to agricultural habitats and may help to develop more effective weed-control practices and breeding better crops. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Román B Vercellino
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Fernando Hernández
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Claudio Pandolfo
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Soledad Ureta
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Alejandro Presotto
- Departamento de Agronomía, CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
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7
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Reducing Seed Shattering in Weedy Rice by Editing SH4 and qSH1 Genes: Implications in Environmental Biosafety and Weed Control through Transgene Mitigation. BIOLOGY 2022; 11:biology11121823. [PMID: 36552332 PMCID: PMC9776087 DOI: 10.3390/biology11121823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/11/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022]
Abstract
Mitigating the function of acquired transgenes in crop wild/weedy relatives can provide an ideal strategy to reduce the possible undesired environmental impacts of pollen-mediated transgene flow from genetically engineered (GE) crops. To explore a transgene mitigation system in rice, we edited the seed-shattering genes, SH4 and qSH1, using a weedy rice line ("C9") that originally had strong seed shattering. We also analyzed seed size-related traits, the total genomic transcriptomic data, and RT-qPCR expression of the SH4 or qSH1 gene-edited and SH4/qSH1 gene-edited weedy rice lines. Substantially reduced seed shattering was observed in all gene-edited weedy rice lines. The single gene-edited weedy rice lines, either the SH4 or qSH1 gene, did not show a consistent reduction in their seed size-related traits. In addition, reduced seed shattering was closely linked with the weakness and absence of abscission layers and reduced abscisic acid (ABA). Additionally, the genes closely associated with ABA biosynthesis and signaling transduction, as well as cell-wall hydrolysis, were downregulated in all gene-edited weedy rice lines. These findings facilitate our deep insights into the underlying mechanisms of reduced seed shattering in plants in the rice genus Oryza. In addition, such a mitigating technology also has practical applications for reducing the potential adverse environmental impacts caused by transgene flow and for managing the infestation of weedy rice by acquiring the mitigator from GE rice cultivars through natural gene flow.
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8
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Laforest M, Martin S, Soufiane B, Bisaillon K, Maheux L, Fortin S, James T, Miville D, Marcoux A, Simard MJ. Distribution and genetic characterization of bird rape mustard (Brassica rapa) populations and analysis of glyphosate resistance introgression. PEST MANAGEMENT SCIENCE 2022; 78:5471-5478. [PMID: 36067042 DOI: 10.1002/ps.7170] [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: 07/20/2022] [Revised: 09/01/2022] [Accepted: 09/06/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND The introgression of a transgene conferring glyphosate resistance from Brassica napus (rapeseed, canola) to Brassica rapa weeds (bird rape) was documented at a single location in 2007. In 2015, several cases of glyphosate resistant mustard were reported by growers in areas where rapeseed was seldom grown. RESULTS Survey result indicated glyphosate resistant bird rape mustard is present in areas where glyphosate tolerant corn and soybean are often grown in rotation. Genetic analyses reveal that hybridization followed by introgression and progressive loss of chromosome is the likely mechanism for the horizontal gene transfer (HGT) of glyphosate resistance. CONCLUSION Introgression of the glyphosate-resistance conferring transgene in the populations studied appears to have occurred several times, consistent with the ease for B. rapa to form hybrids with B. napus. The introduction of a transgene into a crop should therefore take into account the weediness of the species that share a common genome and their ability to form hybrids. We provide here such an example between B. napus and B. rapa, and potentially between B. napus and Raphanistrum raphanistrum. © 2022 Her Majesty the Queen in Right of Canada. Pest Management Science © 2022 Society of Chemical Industry. Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada.
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Affiliation(s)
- Martin Laforest
- Agriculture and Agri-Food Canada (AAFC), Saint-Jean-sur-Richelieu Research and Development Centre, St-Jean-sur-Richelieu, Canada
| | - Sara Martin
- Agriculture and Agri-Food Canada (AAFC), Ottawa Research and Development Centre, Ottawa, Canada
| | - Brahim Soufiane
- Agriculture and Agri-Food Canada (AAFC), Saint-Jean-sur-Richelieu Research and Development Centre, St-Jean-sur-Richelieu, Canada
| | - Katherine Bisaillon
- Royal Canadian Mounted Police, National Forensic Laboratory Services, Surrey, Canada
| | - Lydia Maheux
- Agriculture and Agri-Food Canada (AAFC), Saint-Jean-sur-Richelieu Research and Development Centre, St-Jean-sur-Richelieu, Canada
| | - Sylvain Fortin
- Agriculture and Agri-Food Canada (AAFC), Saint-Jean-sur-Richelieu Research and Development Centre, St-Jean-sur-Richelieu, Canada
| | - Tracey James
- Agriculture and Agri-Food Canada (AAFC), Ottawa Research and Development Centre, Ottawa, Canada
| | - David Miville
- Ministère de l'Agriculture et de l'Alimentation du Québec, Laboratoire d'expertise et de diagnostic en phytoprotection, Québec, Canada
| | - Annie Marcoux
- Ministère de l'Agriculture et de l'Alimentation du Québec, Laboratoire d'expertise et de diagnostic en phytoprotection, Québec, Canada
| | - Marie-Josée Simard
- Agriculture and Agri-Food Canada (AAFC), Saint-Jean-sur-Richelieu Research and Development Centre, St-Jean-sur-Richelieu, Canada
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9
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Hernández F, Vercellino RB, Pandolfo C, Mandel JR, Presotto A. Rapid evolution of seed dormancy during sunflower de-domestication. J Hered 2022; 113:288-297. [PMID: 35192723 DOI: 10.1093/jhered/esac009] [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: 08/27/2021] [Accepted: 02/21/2022] [Indexed: 11/14/2022] Open
Abstract
Hybridization between crops and their wild relatives may promote the evolution of de-domesticated (feral) weeds. Wild sunflower (Helianthus annuus L.) is typically found in ruderal environments, but crop-wild hybridization may facilitate the evolution of weedy populations. Using one crop-specific mitochondrial marker (CMS-PET1) and 14 nuclear SSR markers, we studied the origin and genetic diversity of a recently discovered weedy population of sunflower (named BRW). Then, using a resurrection approach, we tested for rapid evolution of weedy traits (seed dormancy, herbicide resistance, and competitive ability) by sampling weedy and wild populations 10 years apart (2007 and 2017). All the weedy plants present the CMS-PET1 cytotype, confirming their feral origin. At the nuclear markers, BRW showed higher genetic diversity than the cultivated lines and low differentiation with one wild population, suggesting that wild hybridization increased their genetic diversity. We found support for rapid evolution towards higher seed dormancy, but not for higher competitive ability or herbicide resistance. Our results highlight the importance of seed dormancy during the earliest stages of adaptation and show that crop-wild hybrids can evolve quickly in agricultural environments.
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Affiliation(s)
- Fernando Hernández
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés, Bahía Blanca, Argentina.,CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Camino La Carrindanga, Bahía Blanca, Argentina
| | - Roman B Vercellino
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés, Bahía Blanca, Argentina.,CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Camino La Carrindanga, Bahía Blanca, Argentina
| | - Claudio Pandolfo
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés, Bahía Blanca, Argentina.,CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Camino La Carrindanga, Bahía Blanca, Argentina
| | - Jennifer R Mandel
- Department of Biological Sciences, Center for Biodiversity Research, University of Memphis, Memphis, TN
| | - Alejandro Presotto
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés, Bahía Blanca, Argentina.,CERZOS, Universidad Nacional del Sur (UNS)-CONICET, Camino La Carrindanga, Bahía Blanca, Argentina
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10
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Liu L, Zhang L, Fu J, Shen W, Fang Z, Dai Y, Jia R, Liu B, Liang J. Fitness and Ecological Risk of Hybrid Progenies of Wild and Herbicide-Tolerant Soybeans With EPSPS Gene. FRONTIERS IN PLANT SCIENCE 2022; 13:922215. [PMID: 35755711 PMCID: PMC9224928 DOI: 10.3389/fpls.2022.922215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 05/24/2022] [Indexed: 05/11/2023]
Abstract
Exogenous genes of transgenic crops are usually transferred to their wild-type relatives through pollen-mediated gene flow, which may change the ecological fitness and ability to invade wild populations, resulting in the weeding of wild plants and other unpredictable environmental impacts. In this study, the F1 generation of herbicide-resistant soybeans and wild soybeans was obtained by artificial pollination, F2 generation seeds were obtained by self-crossing, and the fitness of the parents and their F1 and F2 generations were tested. The foreign protein EPSPS was expressed normally in the hybrid between transgenic and wild soybeans; however, the protein expression was significantly lower than that in transgenic soybeans. The fitness of the F1 hybrid between transgenic and wild soybeans was significantly lower than that of its parent. Compared with those of the wild soybeans, the F2 generation soybeans improved in some fitness indices, while the emergence rate, pollen germination rate, and number of full seeds per pod, pods per plant, and full seeds per plant did not significantly differ. The aboveground biomass and 100-seed weight of the F2 generation were higher than those of wild soybeans. Fitness among the F2-negative plants, homozygous, and heterozygous positive plants did not significantly vary. Improved fitness and presence of foreign genes in the F2 soybean were not significantly correlated. As the F2 generation of transgenic and wild soybeans had no fitness cost and the flowering stage were overlapped, the foreign gene might still spread in the wild soybean population.
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Affiliation(s)
- Laipan Liu
- Key Laboratory on Biosafety of Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
- State Environmental Protection Scientific Observation and Research Station for Ecology and Environment of Wuyi Mountains, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
| | - Li Zhang
- Key Laboratory on Biosafety of Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
| | - Jianmei Fu
- Key Laboratory on Biosafety of Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
| | - Wenjing Shen
- Key Laboratory on Biosafety of Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
| | - Zhixiang Fang
- Key Laboratory on Biosafety of Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
| | - Ying Dai
- Key Laboratory on Biosafety of Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
| | - Ruizong Jia
- Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off-Season Reproduction Regions, Sanya, China
| | - Biao Liu
- Key Laboratory on Biosafety of Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
- State Environmental Protection Scientific Observation and Research Station for Ecology and Environment of Wuyi Mountains, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing, China
- *Correspondence: Biao Liu,
| | - Jingang Liang
- Development Center of Science and Technology, Ministry of Agriculture and Rural Affairs, Beijing, China
- Jingang Liang,
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11
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Increased Longevity and Dormancy of Soil-Buried Seeds from Advanced Crop–Wild Rice Hybrids Overexpressing the EPSPS Transgene. BIOLOGY 2021; 10:biology10060562. [PMID: 34203092 PMCID: PMC8234842 DOI: 10.3390/biology10060562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 06/06/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022]
Abstract
Simple Summary Estimating the survival and reproductive ability caused by a transgene moved from a genetically engineered (GE) crop to its wild relative populations through gene flow plays an important role in assessing the potential environmental risks of the GE crop. Such estimation has essentially focused on the survival and reproduction-related characteristics above the ground, but with little attention to the GE seeds shattered in the soil seed banks. We demonstrated that the herbicide-resistant transgene overexpressing the rice endogenous EPSP enzyme increased the survival and longevity of the GE crop–wild (Oryza rufipogon) hybrid seeds in soil seed banks. In addition, enhanced survival and longevity of the GE hybrid seeds are likely associated with increases in seed dormancy and a growth hormone (auxin) via overexpressing the EPSPS transgene. Therefore, the EPSPS transgene can persist in the soil seed banks and spread in the environment, causing unwanted environmental impacts. Abstract Estimating the fitness effect conferred by a transgene introgressed into populations of wild relative species from a genetically engineered (GE) crop plays an important role in assessing the potential environmental risks caused by transgene flow. Such estimation has essentially focused on the survival and fecundity-related characteristics measured above the ground, but with little attention to the fate of GE seeds shattered in the soil seed banks after maturation. To explore the survival and longevity of GE seeds in soil, we examined the germination behaviors of crop–wild hybrid seeds (F4–F6) from the lineages of a GE herbicide-tolerant rice (Oryzasativa) line that contains an endogenous EPSPS transgene hybridized with two wild O. rufipogon populations after the seeds were buried in soil. The results showed significantly increased germination of the GE crop–wild hybrid seeds after soil burial, compared with that of the non-GE hybrid seeds. Additionally, the proportion of dormant seeds and the content of the growth hormone auxin (indole-3-acetic acid, IAA) in the GE crop–wild hybrid seeds significantly increased. Evidently, the EPSPS transgene enhances the survival and longevity of GE crop–wild rice seeds in the soil seed banks. The enhanced survival and longevity of the GE hybrid seeds is likely associated with the increases in seed dormancy and auxin (IAA) by overexpressing the rice endogenous EPSPS transgene. Thus, the fate of GE seeds in the soil seed banks should be earnestly considered when assessing the environmental risks caused by transgene flow.
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Baek Y, Bobadilla LK, Giacomini DA, Montgomery JS, Murphy BP, Tranel PJ. Evolution of Glyphosate-Resistant Weeds. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 255:93-128. [PMID: 33932185 DOI: 10.1007/398_2020_55] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Widespread adoption of glyphosate-resistant crops and concomitant reliance on glyphosate for weed control set an unprecedented stage for the evolution of herbicide-resistant weeds. There are now 48 weed species that have evolved glyphosate resistance. Diverse glyphosate-resistance mechanisms have evolved, including single, double, and triple amino acid substitutions in the target-site gene, duplication of the gene encoding the target site, and others that are rare or nonexistent for evolved resistance to other herbicides. This review summarizes these resistance mechanisms, discusses what is known about their evolution, and concludes with some of the impacts glyphosate-resistant weeds have had on weed management.
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Affiliation(s)
- Yousoon Baek
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA
| | - Lucas K Bobadilla
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA
| | - Darci A Giacomini
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA
| | | | - Brent P Murphy
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA
| | - Patrick J Tranel
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA.
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Quilodrán CS, Montoya-Burgos JI, Currat M. Harmonizing hybridization dissonance in conservation. Commun Biol 2020; 3:391. [PMID: 32694629 PMCID: PMC7374702 DOI: 10.1038/s42003-020-1116-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 06/25/2020] [Indexed: 12/24/2022] Open
Abstract
A dramatic increase in the hybridization between historically allopatric species has been induced by human activities. However, the notion of hybridization seems to lack consistency in two respects. On the one hand, it is inconsistent with the biological species concept, which does not allow for interbreeding between species, and on the other hand, it is considered either as an evolutionary process leading to the emergence of new biodiversity or as a cause of biodiversity loss, with conservation implications. In the first case, we argue that conservation biology should avoid the discussion around the species concept and delimit priorities of conservation units based on the impact on biodiversity if taxa are lost. In the second case, we show that this is not a paradox but an intrinsic property of hybridization, which should be considered in conservation programmes. We propose a novel view of conservation guidelines, in which human-induced hybridization may also be a tool to enhance the likelihood of adaptation to changing environmental conditions or to increase the genetic diversity of taxa affected by inbreeding depression. The conservation guidelines presented here represent a guide for the development of programmes aimed at protecting biodiversity as a dynamic evolutionary system.
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Affiliation(s)
- Claudio S Quilodrán
- Department of Zoology, University of Oxford, Oxford, United Kingdom.
- Laboratory of Anthropology, Genetics and Peopling History, Anthropology Unit, Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland.
| | - Juan I Montoya-Burgos
- Laboratory of Vertebrate Evolution, Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland
- Institute of Genetics and Genomics in Geneva (IGE3), Geneva, Switzerland
| | - Mathias Currat
- Laboratory of Anthropology, Genetics and Peopling History, Anthropology Unit, Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland
- Institute of Genetics and Genomics in Geneva (IGE3), Geneva, Switzerland
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Chen R, Shimono A, Aono M, Nakajima N, Ohsawa R, Yoshioka Y. Genetic diversity and population structure of feral rapeseed (Brassica napus L.) in Japan. PLoS One 2020; 15:e0227990. [PMID: 31945118 PMCID: PMC6964882 DOI: 10.1371/journal.pone.0227990] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 01/03/2020] [Indexed: 11/22/2022] Open
Abstract
Rapeseed (Brassica napus L.) is one of the most economically important oilseed crops worldwide. In Japan, it has been cultivated for more than a century and has formed many feral populations. The aim of this study was to elucidate the genetic diversity of feral rapeseeds by genotyping 537 individuals (among which 130 were determined to be genetically modified) sampled from various regions in Japan. Analysis of 30 microsatellite markers amplified 334 alleles and indicated moderate genetic diversity and high inbreeding (expected heterozygosity, 0.50; observed heterozygosity, 0.16; inbreeding coefficient within individuals, 0.68) within the feral populations. The Mantel test showed only an insignificant weak positive correlation between geographic distance and genetic distance. Analysis of molecular variance showed a greater genetic diversity among individuals than between populations. These results are in accordance with population structure assessed by using principal coordinate analysis and the program STRUCTURE, which showed that the 537 individuals could be assigned to 8 genetic clusters with very large genetic differences among individuals within the same geographic population, and that among feral individuals, many are closely related to rapeseed accessions in the NARO Genebank but some have unknown origins. These unique feral rapeseeds are likely to be affected by strong selection pressure. The results for genetically modified individuals also suggest that they have two different sources and have a considerable degree of diversity, which might be explained by hybridization with nearby individuals and separation of hybrid cultivars. The information obtained in this study could help improve the management of feral rapeseed plants in Japan.
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Affiliation(s)
- Ruikun Chen
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Ayako Shimono
- Faculty of Science, Toho University, Funabashi, Chiba, Japan
| | - Mitsuko Aono
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
| | - Nobuyoshi Nakajima
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
| | - Ryo Ohsawa
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yosuke Yoshioka
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
- * E-mail:
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Hernández F, Presotto A, Poverene M, Mandel JR. Genetic Diversity and Population Structure of Wild Sunflower (Helianthus annuus L.) in Argentina: Reconstructing Its Invasion History. J Hered 2019; 110:746-759. [PMID: 31353398 DOI: 10.1093/jhered/esz047] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 07/27/2019] [Indexed: 11/13/2022] Open
Abstract
Studying the levels and patterns of genetic diversity of invasive populations is important to understand the evolutionary and ecological factors promoting invasions and for better designing preventive and control strategies. Wild sunflower (Helianthus annuus L.) is native to North America and was introduced, and has become invasive, in several countries, including Argentina (ARG). Here, using classical population genetic analyses and approximate Bayesian computation (ABC) modeling, we studied the invasion history of wild sunflower in ARG. We analyzed 115 individuals belonging to 15 populations from ARG (invasive range) and United States (US, native range) at 14 nuclear and 3 chloroplast simple sequence repeat markers along with 23 phenotypic variables. Populations from ARG showed similar levels of nuclear genetic diversity to US populations and higher genetic diversity in the chloroplast genome, indicating no severe genetic bottlenecks during the invasion process. Bayesian clustering analysis, based on nuclear markers, suggests the presence of 3 genetic clusters, all present in both US and ARG. Discriminant analysis of principal components (DAPC) detected an overall low population structure between central US and ARG populations but separated 2 invasive populations from the rest. ABC modeling supports multiple introductions but also a southward dispersal within ARG. Genetic and phenotypic data support the central US as a source of introduction while the source of secondary introductions could not be resolved. Finally, using genetic markers from the chloroplast genome, we found lower population structure in ARG when compared with US populations, suggesting a role for seed-mediated gene flow in Argentina.
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Affiliation(s)
- Fernando Hernández
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés 800, Bahía Blanca, Argentina.,Centro de Recursos Naturales Renovables de la Zona Semiárida (CERZOS), CONICET-Bahía Blanca, Bahía Blanca, Argentina
| | - Alejandro Presotto
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés 800, Bahía Blanca, Argentina.,Centro de Recursos Naturales Renovables de la Zona Semiárida (CERZOS), CONICET-Bahía Blanca, Bahía Blanca, Argentina
| | - Mónica Poverene
- Departamento de Agronomía, Universidad Nacional del Sur (UNS), San Andrés 800, Bahía Blanca, Argentina.,Centro de Recursos Naturales Renovables de la Zona Semiárida (CERZOS), CONICET-Bahía Blanca, Bahía Blanca, Argentina
| | - Jennifer R Mandel
- Department of Biological Sciences, University of Memphis, Memphis, TN
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Grantina-Ievina L, Ievina B, Evelone V, Berga S, Kovalcuka L, Bergspica I, Jakovele A, Malisevs A, Valcina O, Rodze I, Rostoks N. Potential risk evaluation for unintended entry of genetically modified plant Propagating material in Europe through import of seeds and animal feed - the experience of Latvia. GM CROPS & FOOD 2019; 10:159-169. [PMID: 31272330 PMCID: PMC6748357 DOI: 10.1080/21645698.2019.1638721] [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: 03/05/2019] [Revised: 06/21/2019] [Accepted: 06/26/2019] [Indexed: 10/26/2022]
Abstract
Significant attention has been drawn to the adventitious and technically unavoidable presence of genetically modified (GM) organisms in the food and feed imported into the European Union (EU), while the potential presence of GM seeds in material for cultivation is less studied. Here we report a study from an EU member state, Latvia, during years 2017-2018 regarding monitoring for the presence of GM seeds in certified seed and animal feed material. Eighty-two and 28 samples of seeds intended for cultivation were analyzed in 2017 and 2018, respectively. One soybean sample contained MON40-3-2 soybean seeds (0.09 ± 0.01%) and one maize sample contained MON810 maize seeds (0.08 ± 0.01%). In addition, 102 samples of feed imported from outside of the EU or produced locally were also analyzed for the presence of genetically modified organisms (GMOs) and viability of grains. One oilseed rape cake sample contained GT73 (1.04 ± 0.01%) and one soybean cake sample contained MON40-3-2 (<0.045%). One sample of declared MON40-3-2 GM soybean cake was confirmed to be positive, with MON40-3-2 content of 94.78 ± 10.01%. One soybean sample submitted by feed producer and originating from Argentina contained 54.9 ± 1.1% of MON40-3-2 and one rapeseed sample originating from Ukraine contained 5.30 ± 3.95% of GT73. Although only two seed samples contained low levels of GMOs authorized in the EU for food and feed uses, this study reinforced the need to maintain regular monitoring programs that assist farmers in their efforts to comply with the current EU GMO legislation.
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Affiliation(s)
| | - Baiba Ievina
- Department of Plant quarantine, State Plant Protection Service, Riga, Latvia
| | - Velta Evelone
- Seed Control Department, State Plant Protection Service, Riga, Latvia
| | - Solvita Berga
- Seed Control Department, State Plant Protection Service, Riga, Latvia
| | - Lilija Kovalcuka
- Institute of Food Safety, Animal Health and Environment “BIOR”, Riga, Latvia
| | - Ieva Bergspica
- Institute of Food Safety, Animal Health and Environment “BIOR”, Riga, Latvia
| | - Alise Jakovele
- Institute of Food Safety, Animal Health and Environment “BIOR”, Riga, Latvia
| | - Artjoms Malisevs
- Institute of Food Safety, Animal Health and Environment “BIOR”, Riga, Latvia
| | - Olga Valcina
- Institute of Food Safety, Animal Health and Environment “BIOR”, Riga, Latvia
| | - Ieva Rodze
- Institute of Food Safety, Animal Health and Environment “BIOR”, Riga, Latvia
| | - Nils Rostoks
- Faculty of Biology, University of Latvia, Riga, Latvia
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Re-establishment of latitudinal clines and local adaptation within the invaded area suggest rapid evolution of seed traits in Argentinean sunflower (Helianthus annuus L.). Biol Invasions 2019. [DOI: 10.1007/s10530-019-01998-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Mikhaylova EV, Kuluev BR. Potential for gene flow from genetically modified Brassica napus on the territory of Russia. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:557. [PMID: 30159768 DOI: 10.1007/s10661-018-6946-2] [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: 03/24/2018] [Accepted: 08/22/2018] [Indexed: 06/08/2023]
Abstract
Gene flow from genetically modified crops has been studied for more than 20 years, but public concern still remains. A lot of data on this matter is obtained on the territory of EU and the USA, but in the majority of countries, such experiments were never carried out. Here, we present the first study of interspecific and intraspecific hybridization of transgenic Brassica napus on the territory of Russia. The experiment was conducted using two different models of coexistence. Cross-pollination with related species was more frequent in mixed than that in separated populations. We observed maximum 4.1% of transgenic seeds in the progeny of Brassica rapa and 0.6% in the progeny of Brassica juncea. The highest intraspecific hybridization rate of 0.67% was observed in separated populations. DNA fragments, typical to both parents, were present in the genome of the hybrids. The risk of gene flow in Russia is relatively low, but it will be problematic to do environmental monitoring on such a big territory. However, instead of banning the cultivation of genetically modified crops, some new varieties with visually detectable selective traits could be designed and approved for cultivation.
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Affiliation(s)
- Elena V Mikhaylova
- Laboratory of Bioengineering of plants and microorganisms, Institute of Biochemistry and Genetics UFRC RAS, Prospekt Oktabrya, 71, Ufa, Russian Federation, 450054.
| | - Bulat R Kuluev
- Laboratory of Bioengineering of plants and microorganisms, Institute of Biochemistry and Genetics UFRC RAS, Prospekt Oktabrya, 71, Ufa, Russian Federation, 450054
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Ellstrand NC. "Born to Run"? Not Necessarily: Species and Trait Bias in Persistent Free-Living Transgenic Plants. Front Bioeng Biotechnol 2018; 6:88. [PMID: 30018952 PMCID: PMC6037855 DOI: 10.3389/fbioe.2018.00088] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/12/2018] [Indexed: 12/02/2022] Open
Abstract
The possibility of transgenes from engineered plants ending up in unmanaged populations with undesirable consequences has been a long-term biosafety concern. Experience with traditionally improved plants reveals that most cases of such gene escape have been of little consequence, but on occasion they have led to the evolution of problematic plants or have resulted in an increased extinction risk for wild taxa. Three decades have passed since the first environmental release of transgenic plants, and more than two decades since their first commercialization. Examples of transgenes gone astray are increasingly commonplace. Transgenic individuals have been identified in more than a thousand free-living plant populations. Here I review 14 well-documented consolidated “cases” in which transgenes have found their way into free-living plant populations. Some as transient volunteers; others appear to be persistent transgenic populations. The species involved in the latter are not representative of the current commercialized transgenic crops as whole. They tend to share certain traits that are absent or rare in the transgenic crops that do not exist as persistent populations. The traits commonly occurring in species with persistent transgenic free-living populations are the following, in descending order of importance: (1) a history of occurring as non-transgenic free-living plants, (2) fruits fully or partially shattering prior to harvest, (3) have small or otherwise easily dispersed seeds, either spontaneously or by seed spillage along the supply chain from harvest to consumer, (4) ability to disperse viable pollen, especially to a kilometer or more, (5) perennial habit, and (6) the transgene's fitness effects in the recipient environment are beneficial or neutral. Based on these observations, a thought experiment posits which species might be the next to be reported to occur as free-living transgenic populations.
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Affiliation(s)
- Norman C Ellstrand
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA, United States
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