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Elkins BH, Portilla M, Allen KC, Little NS, Mullen RM, Paulk RT, Read QD. Sublethal effects of a commercial Bt product and Bt cotton flowers on the bollworm (Helicoverpa zea) with impacts to predation from a lady beetle (Hippodamia convergens). PLoS One 2024; 19:e0302941. [PMID: 38709777 PMCID: PMC11073675 DOI: 10.1371/journal.pone.0302941] [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: 10/26/2023] [Accepted: 04/15/2024] [Indexed: 05/08/2024] Open
Abstract
Insecticidal Bacillus thuringiensis Berliner (Bt) toxins produced by transgenic cotton (Gossypium hirsutum L.) plants have become an essential component of cotton pest management. Bt toxins are the primary management tool in transgenic cotton for lepidopteran pests, the most important of which is the bollworm (Helicoverpa zea Boddie) (Lepidoptera: Noctuidae) in the United States (U.S.). However, bollworm larvae that survive after consuming Bt toxins may experience sublethal effects, which could alter interactions with other organisms, such as natural enemies. Experiments were conducted to evaluate how sublethal effects of a commercial Bt product (Dipel) incorporated into artificial diet and from Bt cotton flowers impact predation from the convergent lady beetle (Hippodamia convergens Guérin-Méneville) (Coleoptera: Coccinellidae), common in cotton fields of the mid-southern U.S. Sublethal effects were detected through reduced weight and slower development in bollworm larvae which fed on Dipel incorporated into artificial diet, Bollgard II, and Bollgard 3 cotton flowers. Sublethal effects from proteins incorporated into artificial diet were found to significantly alter predation from third instar lady beetle larvae. Predation of bollworm larvae also increased significantly after feeding for three days on a diet incorporated with Bt proteins. These results suggest that the changes in larval weight and development induced by Bt can be used to help predict consumption of bollworm larvae by the convergent lady beetle. These findings are essential to understanding the potential level of biological control in Bt cotton where lepidopteran larvae experience sublethal effects.
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Affiliation(s)
- Blake H. Elkins
- Southern Insect Management Research Unit, USDA-ARS, Stoneville, MS, United States of America
| | - Maribel Portilla
- Southern Insect Management Research Unit, USDA-ARS, Stoneville, MS, United States of America
| | - Kerry Clint Allen
- Southern Insect Management Research Unit, USDA-ARS, Stoneville, MS, United States of America
| | - Nathan S. Little
- Southern Insect Management Research Unit, USDA-ARS, Stoneville, MS, United States of America
| | - Regina M. Mullen
- Southern Insect Management Research Unit, USDA-ARS, Stoneville, MS, United States of America
| | - Ryan T. Paulk
- Southern Insect Management Research Unit, USDA-ARS, Stoneville, MS, United States of America
| | - Quentin D. Read
- Southeast Area, USDA-ARS, Raleigh, NC, United States of America
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2
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Cai L, Liu X, Tian Z, Michaud JP, Shen Z, Li Z, Zhang S, Liu X. Safety of Bacillus thuringiensis Cry1Ah and Vip3Aa toxins for the predatory stink bug Arma custos (Hemiptera: Pentatomidae). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158120. [PMID: 35987246 DOI: 10.1016/j.scitotenv.2022.158120] [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: 05/13/2022] [Revised: 08/05/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
The widespread adoption of Bt crops expressing insecticidal proteins derived from Bacillus thuringiensis has created a need to assess the potential effects of these toxins on non-target organisms, especially species such as Arma custos, a generalist predator that provides important biological control services in many field crops in Asia. Direct dietary exposure of A. custos to Cry1Ah and Vip3Aa proteins produced no adverse effects on life history traits, despite continuous exposure throughout development and early adult life to concentrations significantly higher than the Bt protein concentration likely encountered by A.custos in the field, even when feeding directly on Bt plants. Enzyme-linked immunosorbent assay confirmed the presence of Bt proteins in A. custos midguts, but quantitative real-time PCR analysis of 12 genes associated with detoxification, antioxidative responses, immune responses, and metabolism revealed no significant changes in expression in adult bugs. Indirect exposure to these toxins via consumption of intoxicated prey, larvae of Helicoverpa armigera (Hübner), likewise produced no negative impacts on survival, development, adult weight, or female fecundity in either the F0 (exposed) or F1 (unexposed) generation, but female fresh weight was reduced in the F0 generation by the Cry1Ah (50 μg/g) treatment. Finally, a competitive binding assay with labelled protein and a ligand blotting assay both demonstrated that the Cry1Ah protein could not bind to receptors on the midgut brush border membrane vesicles (BBMVs) of A. custos adults. Therefore, we conclude that Cry1Ah and Vip3Aa proteins are unlikely to have significant negative effects on A. custos populations if employed as plant-incorporated protectants in field crops.
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Affiliation(s)
- Limei Cai
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193 Beijing, China
| | - Xiaoming Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193 Beijing, China
| | - Zhiqiang Tian
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193 Beijing, China
| | - J P Michaud
- Department of Entomology, Kansas State University, Agricultural Research Station-Hays, Hays, KS 67601, USA
| | - Zhongjian Shen
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193 Beijing, China
| | - Zhen Li
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193 Beijing, China
| | - Songdou Zhang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193 Beijing, China
| | - Xiaoxia Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193 Beijing, China.
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3
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Antonelli P, Duval P, Luis P, Minard G, Valiente Moro C. Reciprocal interactions between anthropogenic stressors and insect microbiota. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:64469-64488. [PMID: 35864395 DOI: 10.1007/s11356-022-21857-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
Insects play many important roles in nature due to their diversity, ecological role, and impact on agriculture or human health. They are directly influenced by environmental changes and in particular anthropic activities that constitute an important driver of change in the environmental characteristics. Insects face numerous anthropogenic stressors and have evolved various detoxication mechanisms to survive and/or resist to these compounds. Recent studies highligted the pressure exerted by xenobiotics on insect life-cycle and the important role of insect-associated bacterial microbiota in the insect responses to environmental changes. Stressor exposure can have various impacts on the composition and structure of insect microbiota that in turn may influence insect biology. Moreover, bacterial communities associated with insects can be directly or indirectly involved in detoxification processes with the selection of certain microorganisms capable of degrading xenobiotics. Further studies are needed to assess the role of insect-associated microbiota as key contributor to the xenobiotic metabolism and thus as a driver for insect adaptation to polluted habitats.
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Affiliation(s)
- Pierre Antonelli
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, 69622, Villeurbanne, France
| | - Pénélope Duval
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, 69622, Villeurbanne, France
| | - Patricia Luis
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, 69622, Villeurbanne, France
| | - Guillaume Minard
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, 69622, Villeurbanne, France
| | - Claire Valiente Moro
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, 69622, Villeurbanne, France.
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4
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Yin Y, Xu Y, Cao K, Zhao X, Cao C, Dong X, Liang J, Shi W. Effect of genetically modified maize expressing the Cry1Ab and EPSPS proteins on growth, development, and gut bacterial diversity of the non-target arthropod Locusta migratoria. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:63837-63845. [PMID: 35467188 DOI: 10.1007/s11356-022-20147-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
The widespread cultivation of genetically modified (GM) crops has raised concerns for their safety. Here, we evaluated the effects of a GM maize variety expressing the Cry1Ab (14.76 ± 0.87 μg/g FW) and EPSPS proteins (191.55 ± 15.69 μg/g FW) on the life-history traits and gut bacterial community of a non-target arthropod, Locusta migratoria, in the laboratory. We found that GM maize had no significant effect on the survival or body weight of different development stages of L. migratoria. The midgut and hindgut bacterial diversities and compositions were determined using high-throughput sequencing targeting the V3-V4 regions of the 16S rRNA. No significant changes were found in the species diversity or abundance between insects in the GM-fed treatment and the non-GM control. Furthermore, the concentration of Cry1Ab and EPSPS in the gut was determined after digestion of GM maize. Results showed that the contents of Cry1Ab/EPSPS rapidly decreased and were hard to detect after 72 h. Based on the parameters assessed, we can conclude that the GM maize variety examined has no significant adverse effect on L. migratoria.
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Affiliation(s)
- Yue Yin
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing, 100094, China
| | - Yudi Xu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing, 100094, China
| | - Kaili Cao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing, 100094, China
| | - Xinxin Zhao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing, 100094, China
| | - Chuan Cao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing, 100094, China
| | - Xuehui Dong
- Department of Agriculture Science, China Agricultural University, Beijing, 100094, China
| | - Jingang Liang
- Development Center of Science and Technology, Ministry of Agriculture and Rural Affairs, Beijing, 100176, China
| | - Wangpeng Shi
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, China Agricultural University, Beijing, 100094, China.
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Marques LH, Lepping M, Castro BA, Santos AC, Rossetto J, Nunes MZ, Silva OABN, Moscardini VF, de Sá VGM, Nowatzki T, Dahmer ML, Gontijo PC. Field efficacy of Bt cotton containing events DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 against lepidopteran pests and impact on the non-target arthropod community in Brazil. PLoS One 2021; 16:e0251134. [PMID: 33945577 PMCID: PMC8096009 DOI: 10.1371/journal.pone.0251134] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 04/21/2021] [Indexed: 11/19/2022] Open
Abstract
The efficacy and non-target arthropod effects of transgenic DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 Bt cotton, expressing proteins Cry1Ac, Cry1F and Vip3Aa19, was examined through field trials in Brazil. Fifteen field efficacy experiments were conducted from 2014 through the 2020 growing season across six different states in Brazil to evaluate performance against key lepidopteran pests through artificial infestations of Chrysodeixis includens (Walker), Spodoptera frugiperda (J.E. Smith,1797), Spodoptera cosmioides (Walker, 1858) and Chloridea virescens (F., 1781), and natural infestations of Alabama argillacea (Hübner) and S. frugiperda. The impact of this Bt cotton technology on the non-target arthropod community in Brazilian cotton production systems was also assessed in a multi-site experiment. DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 cotton significantly reduced the feeding damage caused by S. frugiperda, S. cosmioides, C. includens, C. virescens and A. argillacea, causing high levels of mortality (greater than 99%) to all target lepidopteran pests evaluated during vegetative and/or reproductive stages of crop development. Non-target arthropod community-level analyses confirmed no unintended effects on the arthropod groups monitored. These results demonstrate the value of transgenic Bt cotton containing event DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 for consideration as part of an integrated approach for managing key lepidopteran pests in Brazilian cotton production systems.
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Affiliation(s)
| | - Miles Lepping
- Corteva Agriscience, Indianapolis, Indiana, United States of America
| | - Boris A. Castro
- Corteva Agriscience, Indianapolis, Indiana, United States of America
| | | | | | | | | | | | | | | | - Mark L. Dahmer
- Corteva Agriscience, Johnston, Iowa, United States of America
| | - Pablo C. Gontijo
- Instituto Federal Goiano, Campus Rio Verde, Rio Verde, Goiás, Brazil
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Kanagasubbulakshmi S, Kadirvelu K. Paper-Based Simplified Visual Detection of Cry2Ab Insecticide from Transgenic Cottonseed Samples Using Integrated Quantum Dots-IgY Antibodies. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:4074-4080. [PMID: 33789050 DOI: 10.1021/acs.jafc.0c07180] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In the present study, an easy to use field-deployable methodology was developed for onsite detection of pesticidal crystal protein Cry2Ab from transgenic cotton crops to reduce seed adulteration. Anti Cry2Ab IgG and IgY antibodies were developed against recombinant Cry2Ab protein in New Zealand white rabbits and in white leg horn chickens, respectively. Carboxyl-functionalized CdTe quantum dots (QDs) were used as revealing probes, and nitrocellulose paper was used as an assay matrix. Recombinant Cry2Ab was generated in the lab and used for immunization of chicken and rabbits. After successful immunization and attaining the desired titer values (1:32 000 for IgY and 1:64 000 for IgG), eggs and hyperimmune sera were collected. Anti Cry2Ab IgY was purified as per the standardized protocols, and anti Cry2Ab IgG was purified using protein A affinity chromatography. Sensitivity of the generated antibodies was examined using indirect ELISA methods against recombinant Cr2Ab protein. Specificity evaluation was carried out against other Cry proteins including Cry2Ab, Cry4b, Cry4a, Cry1Ec, and Cry1Ac. Functionalized CdTe QDs were characterized for structure and shape as well as fluorescence properties using standard laboratory techniques. A field-deployable paper-based detection methodology was developed where IgG acted as the capturing antibody and IgY-linked CdTe QDs were used as revealing probes. The limit of detection (LOD) and quantification (LOQ) were found to be 2.91 ng/mL and 9.71 ng/mL, respectively. The effect of matrix interference was assessed on the different plant crude extracts of cottonseed materials.
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Affiliation(s)
- S Kanagasubbulakshmi
- DRDO-BU Center for Life Sciences, Bharathiar University Campus, Coimbatore-641046, Tamilnadu, India
| | - K Kadirvelu
- DRDO-BU Center for Life Sciences, Bharathiar University Campus, Coimbatore-641046, Tamilnadu, India
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7
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Pan H, Yang X, Romeis J, Siegfried BD, Zhou X. Dietary RNAi toxicity assay exhibits differential responses to ingested dsRNAs among lady beetles. PEST MANAGEMENT SCIENCE 2020; 76:3606-3614. [PMID: 32400940 DOI: 10.1002/ps.5894] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/21/2020] [Accepted: 05/13/2020] [Indexed: 05/23/2023]
Abstract
BACKGROUND Most recently, major federal regulatory agencies deregulated an in planta RNA interference (RNAi) trait against a devastating corn pest, the western corn rootworm Diabrotica virgifera virgifera, in the United States and Canada. The impact of double-stranded RNA (dsRNA) plant-incorporated protectants (PIPs) and dietary RNAi to non-target organisms, however, still needs further investigation. In this study, we assessed the potential risks of a Diabrotica virgifera virgifera active dsRNA to a group of predatory biological control agents, including Hippodamia convergens, Harmonia axyridis, Coleomegilla maculata, and Coccinella septempunctata. The overarching hypothesis is that the insecticidal dsRNA targeting Diabrotica virgifera virgifera has no or negligible adverse effect on lady beetles. RESULTS A 400-bp fragment with the highest sequence similarity between target and tested species was selected as the template for dsRNA synthesis. For the dietary RNAi toxicity assay, newly hatched first instar larvae were administered with v-ATPase A dsRNAs designed from Diabrotica virgifera virgifera and the four lady beetles, respectively. A dsRNA from β-glucuronidase (GUS), a plant gene, and H2 O were served as the negative controls. The endpoint included both sub-organismal (gene expression), and organismal (survival rate, development time, pupa and adult weight) measurements. The results from dietary RNAi toxicity assay demonstrate significantly impacts of Diabrotica virgifera virgifera-active dsRNAs on lady beetles under the worst-case scenario at both transcriptional and phenotypic level. Interestingly, substantial differences among the four lady beetle species were observed toward the ingested exogenous dsRNAs. CONCLUSION Such differential response to dietary RNAi may shed light on the mechanisms underlying the mode-of-action of RNAi-based biopesticides. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Huipeng Pan
- Key Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, South China Agricultural University, Guangzhou, China
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | - Xiaowei Yang
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | - Jörg Romeis
- Agroscope, Research Division Agroecology and Environment, Zurich, Switzerland
| | - Blair D Siegfried
- Department of Entomology and Nematology, University of Florida, Gainesville, FL, USA
| | - Xuguo Zhou
- Department of Entomology, University of Kentucky, Lexington, KY, USA
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Azizoglu U, Jouzani GS, Yilmaz N, Baz E, Ozkok D. Genetically modified entomopathogenic bacteria, recent developments, benefits and impacts: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 734:139169. [PMID: 32460068 DOI: 10.1016/j.scitotenv.2020.139169] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/10/2020] [Accepted: 04/30/2020] [Indexed: 06/11/2023]
Abstract
Entomopathogenic bacteria (EPBs), insect pathogens that produce pest-specific toxins, are environmentally-friendly alternatives to chemical insecticides. However, the most important problem with EPBs application is their limited field stability. Moreover, environmental factors such as solar radiation, leaf temperature, and vapor pressure can affect the pathogenicity of these pathogens and their toxins. Scientists have conducted intensive research to overcome such problems. Genetic engineering has great potential for the development of new engineered entomopathogens with more resistance to adverse environmental factors. Genetically modified entomopathogenic bacteria (GM-EPBs) have many advantages over wild EPBs, such as higher pathogenicity, lower spraying requirements and longer-term persistence. Genetic manipulations have been mostly applied to members of the bacterial genera Bacillus, Lysinibacillus, Pseudomonas, Serratia, Photorhabdus and Xenorhabdus. Although many researchers have found that GM-EPBs can be used safely as plant protection bioproducts, limited attention has been paid to their potential ecological impacts. The main concerns about GM-EPBs and their products are their potential unintended effects on beneficial insects (predators, parasitoids, pollinators, etc.) and rhizospheric bacteria. This review address recent update on the significant role of GM-EPBs in biological control, examining them through different perspectives in an attempt to generate critical discussion and aid in the understanding of their potential ecological impacts.
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Affiliation(s)
- Ugur Azizoglu
- Department of Crop and Animal Production, Safiye Cikrikcioglu Vocational College, Kayseri University, Kayseri, Turkey.
| | - Gholamreza Salehi Jouzani
- Microbial Biotechnology Department, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - Nihat Yilmaz
- Department of Crop and Animal Production, Safiye Cikrikcioglu Vocational College, Kayseri University, Kayseri, Turkey
| | - Ethem Baz
- Laboratory and Veterinary Health Department, Safiye Cikrikcioglu Vocational College, Kayseri University, Kayseri, Turkey
| | - Duran Ozkok
- Department of Crop and Animal Production, Safiye Cikrikcioglu Vocational College, Kayseri University, Kayseri, Turkey
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Zhao C, Wu L, Luo J, Niu L, Wang C, Zhu X, Wang L, Zhao P, Zhang S, Cui J. Bt, Not a Threat to Propylea japonica. Front Physiol 2020; 11:758. [PMID: 32903558 PMCID: PMC7438476 DOI: 10.3389/fphys.2020.00758] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 06/11/2020] [Indexed: 11/14/2022] Open
Abstract
Given the ever-increasing commercial planting of transgenic plants across the world, an evaluation of their impacts on non-target organisms is as an important part of the risk assessment process. Propylea japonica is a dominant non-target predator and pollen feeder insect that is prevalent in Bt cotton fields, and it is thus in direct contact with Bt proteins. However, the effect of Bt proteins on P. japonica has not received much attention. In this study, the effects of Cry1Ac and/or Cry2Ab proteins on P. japonica were investigated from three aspects. First, no significant differences in the diversity of the microbiota nor change in species composition and community structure were observed among Cry protein treatments. Firmicutes are the most abundant bacterial phylum present in P. japonica, followed by Proteobacteria and Actinobacteria. The most abundant genus was Staphylococcus. Second, the expression levels of the detoxification and digestion-related genes did not change significantly in any Cry protein treatment. Third, none of the Cry proteins affected the population fitness of P. japonica. These results indicated that P. japonica was not sensitive to Bt proteins, suggesting that growing Bt cotton expressing Cry1Ac and/or Cry2Ab will pose negligible risks to P. japonica.
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Affiliation(s)
- Chenchen Zhao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China.,Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Linke Wu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Junyu Luo
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Lin Niu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China.,Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China
| | - Chuanpeng Wang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Xiangzhen Zhu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Li Wang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Peng Zhao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Shuai Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China.,College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China
| | - Jinjie Cui
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China.,Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China
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10
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Tang Q, Yang Z, Han R, Zhang Y, Shen C, Wang J. No Effect of Bt-transgenic Rice on the Tritrophic Interaction of the Stored Rice, the Maize Weevil Sitophilus Zeamais and the Parasitoid Wasp Theocolax elegans. Sci Rep 2019; 9:4306. [PMID: 30867515 PMCID: PMC6416355 DOI: 10.1038/s41598-019-40836-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 02/19/2019] [Indexed: 12/19/2022] Open
Abstract
During Bt transgenic rice storage, Bt Cry1Ab/Cry1Ac fused protein is exposed to the maize weevil Sitophilus zeamais and the parasitoid wasp Theocolax elegans. We have carried out a long-term risk assessment for Bt rice to these non-target organisms in the storehouse. Effects of Bt rice on S. zeamais and T. elegans have been carefully detected in a laboratory experiment of over 5 years. The survival, development, fecundity, and longevity of the maize weevil were compared between Bt rice and non-Bt rice treatments for every 5 generations from generation 1 to 25. Moreover, the development, adult body size and sex ratio of T. elegans were compared between them parasitizing S. zeamais feeding on Bt rice or non-Bt rice. We found that although Bt Cry1Ab/Cry1Ac fused protein exists in the Bt rice grains and S. zeamais digestive tracts, Bt rice is not harmful to the maize weevil S. zeamais and its parasitoid T. elegans.
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Affiliation(s)
- Qingfeng Tang
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China
| | - Zhipeng Yang
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China
| | - Rongrong Han
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China
| | - Ying Zhang
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China
| | - Chen Shen
- Department of Entomology, College of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China
| | - Jian Wang
- Department of Entomology, University of Maryland, College Park, MD, 20742, USA.
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11
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Meissle M, Romeis J. Transfer of Cry1Ac and Cry2Ab proteins from genetically engineered Bt cotton to herbivores and predators. INSECT SCIENCE 2018; 25:823-832. [PMID: 28374515 DOI: 10.1111/1744-7917.12468] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/09/2017] [Accepted: 03/06/2017] [Indexed: 06/07/2023]
Abstract
With the cultivation of Bt cotton, the produced insecticidal Cry proteins are ingested by herbivores and potentially transferred along the food chain to natural enemies, such as predators. In laboratory experiments with Bollgard II cotton, concentrations of Cry1Ac and Cry2Ab were measured in Lepidoptera larvae (Spodoptera littoralis, Heliothis virescens), plant bugs (Euschistus heros), aphids (Aphis gossypii), whiteflies (Bemisia tabaci), thrips (Thrips tabaci, Frankliniella occidentalis), and spider mites (Tetranychus urticae). Tritrophic experiments were conducted with caterpillars of S. littoralis as prey and larvae of ladybird beetles (Harmonia axyridis, Adalia bipunctata) and lacewings (Chrysoperla carnea) as predators. Immunological measurements (ELISA) indicated that herbivores feeding on Bt cotton contained 5%-50% of the Bt protein concentrations in leaves except whiteflies and aphids, which contained no or only traces of Bt protein, and spider mites, which contained 7 times more Cry1Ac than leaves. Similarly, predators contained 1%-30% of the Cry protein concentration in prey. For the nontarget risk assessment, this indicates that Bt protein concentrations decrease considerably from one trophic level to the next in the food web, except for spider mites that contain Bt protein concentrations higher than those measured in the leaves. Exposure of phloem sucking hemipterans is negligible.
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Affiliation(s)
- Michael Meissle
- Agroscope Research Division Agroecology and Environment, Zürich, Switzerland
| | - Jörg Romeis
- Agroscope Research Division Agroecology and Environment, Zürich, Switzerland
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Wang Y, Li D, Zhou H, Liu H, Niu L, Wang L, Ma W. Evaluation of Cry1Ac and Cry2Aa Toxin Binding to Two Important Beneficial Cotton Field Insects, Harmonia axyridis and Orius similis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:8698-8702. [PMID: 30059215 DOI: 10.1021/acs.jafc.8b02634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Transgenic crops expressing Cry toxins are effective and considered environmentally friendly alternatives to synthetic pesticides, but assessment of environmental risks of their application on nontarget organisms is ongoing. The main risk is the transfer of Cry toxins to natural enemies through the food chain. There is reported evidence supporting that Cry toxins can be detected in the body and gut of some natural enemy insects. Considering that binding of Cry toxins to insect proteins is an essential step in the intoxication process, this work was conducted to evaluate interactions between Cry1Ac and Cry2Aa toxins with proteins from larvae/nymphs and adults of two important predatory natural enemies in cotton fields, Harmonia axyridis and Orius similis. Results support the absence of Cry1Ac or Cry2Aa binding proteins in immature stages of H. axyridis and O. similis, as well as in imaginal stage of H. axyridis. One same binding band about 70 kDa was found in imaginal total protein of O. similis when probed with the two Cry proteins, with the best match to Hsc70 of O. sauteri in the Uniprot database. However, nonspecific binding was verified by following competitive binding assays between the two Cry proteins and imaginal total protein of O. similis. From these results, we may infer that Cry1Ac and Cry2Aa have no likely detrimental effects on H. axyridis and O. similis.
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Affiliation(s)
- Yong Wang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory , Huazhong Agricultural University , Wuhan 430070 , China
- Hubei Key Laboratory of Quality Control of Characteristic Fruits and Vegetables , Hubei Engineering University , Xiaogan 432000 , China
| | - Dabo Li
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory , Huazhong Agricultural University , Wuhan 430070 , China
- Yichang Institute of Termite Control , Yichang 443000 , China
| | - Hao Zhou
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory , Huazhong Agricultural University , Wuhan 430070 , China
| | - Hui Liu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory , Huazhong Agricultural University , Wuhan 430070 , China
| | - Lin Niu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory , Huazhong Agricultural University , Wuhan 430070 , China
| | - Lihua Wang
- Hubei Key Laboratory of Quality Control of Characteristic Fruits and Vegetables , Hubei Engineering University , Xiaogan 432000 , China
| | - Weihua Ma
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory , Huazhong Agricultural University , Wuhan 430070 , China
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Marques LH, Santos AC, Castro BA, Storer NP, Babcock JM, Lepping MD, Sa V, Moscardini VF, Rule DM, Fernandes OA. Impact of transgenic soybean expressing Cry1Ac and Cry1F proteins on the non-target arthropod community associated with soybean in Brazil. PLoS One 2018; 13:e0191567. [PMID: 29394266 PMCID: PMC5796694 DOI: 10.1371/journal.pone.0191567] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 01/08/2018] [Indexed: 11/20/2022] Open
Abstract
Field-scale studies that examine the potential for adverse effects of Bt crop technology on non-target arthropods may supplement data from laboratory studies to support an environmental risk assessment. A three year field study was conducted in Brazil to evaluate potential for adverse effects of cultivating soybean event DAS-81419-2 that produces the Cry1Ac and Cry1F proteins. To do so, we examined the diversity and abundance of non-target arthropods (NTAs) in Bt soybean in comparison with its non-Bt near isoline, with and without conventional insecticide applications, in three Brazilian soybean producing regions. Non-target arthropod abundance was surveyed using Moericke traps (yellow pan) and pitfall trapping. Total abundance (N), richness (S), Shannon-Wiener (H'), Simpson's (D) and Pielou's evenness (J) values for arthropod samples were calculated for each treatment and sampling period (soybean growth stages). A faunistic analysis was used to select the most representative NTAs which were used to describe the NTA community structure associated with soybean, and to test for effects due to the treatments effects via application of the Principal Response Curve (PRC) method. Across all years and sites, a total of 254,054 individuals from 190 taxa were collected by Moericke traps, while 29,813 individuals from 100 taxa were collected using pitfall traps. Across sites and sampling dates, the abundance and diversity measurements of representative NTAs were not significantly affected by Bt soybean as compared with non-sprayed non-Bt soybean. Similarly, community analyses and repeated measures ANOVA, when applicable, indicated that neither Bt soybean nor insecticide sprays altered the structure of the NTA communities under study. These results support the conclusion that transgenic soybean event DAS-81419-2 producing Cry1Ac and Cry1F toxins does not adversely affect the NTA community associated with soybean.
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Affiliation(s)
- Luiz H. Marques
- Dow AgroSciences Industrial Ltda, São Paulo, São Paulo, Brazil
| | | | - Boris A. Castro
- Dow AgroSciences LLC, Indianapolis, Indiana, United States of America
| | | | | | - Miles D. Lepping
- Dow AgroSciences LLC, Indianapolis, Indiana, United States of America
| | - Verissimo Sa
- Dow AgroSciences Industrial Ltda, São Paulo, São Paulo, Brazil
| | | | - Dwain M. Rule
- Dow AgroSciences LLC, Indianapolis, Indiana, United States of America
| | - Odair A. Fernandes
- Universidade Estadual Paulista (FCAV/UNESP), Faculdade de Ciências Agrárias e Veterinárias, FCAV/UNESP, Jaboticabal, São Paulo, Brazil
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Bt cotton producing Cry1Ac and Cry2Ab does not harm two parasitoids, Cotesia marginiventris and Copidosoma floridanum. Sci Rep 2018; 8:307. [PMID: 29321488 PMCID: PMC5762887 DOI: 10.1038/s41598-017-18620-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 12/06/2017] [Indexed: 11/29/2022] Open
Abstract
Cabbage looper, Trichoplusia ni (Hübner) is an important lepidopteran pest on many vegetable and greenhouse crops, and some field crops. Although there are no commercial transgenic Bt vegetable or greenhouse crops, T. ni is a target of Bollgard II cotton, which produces Cry1Ac and Cry2Ab. We expand on previous work that examined the effect of Bt crops on parasitoids using Bt-resistant lepidopteran populations as hosts. Cry1Ac/Cry2Ab-resistant T. ni larvae were used to eliminate host quality effects and to evaluate the direct effects of Bt cotton on the parasitoids Copidosoma floridanum (Ashmead) and Cotesia marginiventris (Cresson). These tri-trophic studies confirm that Bt cotton had no significant impact on development, success of parasitism, survival and adult longevity of C. marginiventris when using Bt-resistant T. ni fed on Bt cotton. Similarly, this Bt cotton had no significant impact on the development, mummy weight and the number of progeny produced by C. floridanum. Our studies verified that lyophilized Bt crop tissue maintained its insecticidal bioactivity when incorporated into an artificial diet, demonstrating that hosts and parasitoids were exposed to active Cry proteins. The egg-larval parasitoid C. floridanum, or similar species that consume their entire host, should be considered useful surrogates in risk assessment of Bt crops to non-target arthropods.
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Chang X, Lu Z, Shen Z, Peng Y, Ye G. Bitrophic and Tritrophic Effects of Transgenic cry1Ab/cry2Aj Maize on the Beneficial, Nontarget Harmonia axyridis (Coleoptera: Coccinellidae). ENVIRONMENTAL ENTOMOLOGY 2017; 46:1171-1176. [PMID: 28981636 DOI: 10.1093/ee/nvx113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Indexed: 06/07/2023]
Abstract
Harmonia axyridis (Pallas) is a common and abundant predator in China and may be exposed to Cry toxins that are produced in Bt crops either by feeding on plant parts or by feeding on target or nontarget herbivorous insects. A new Bt maize line, expressing the Cry1Ab/Cry2Aj fused protein, has been developed and should be rigorously assessed for the ecological risks on the natural enemy. Laboratory experiments were carried out to study the effects of this Bt maize on nontarget predator H. axyridis via bitrophic interaction of adult H. axyridis feeding on Bt maize pollen and tritrophic interaction of H. axyridis consuming the lepidopteran prey. Spodoptera exigua (Hübner) neonate larvae were used to transfer Bt protein because they could survive after ingesting transgenic cry1Ab/cry2Aj maize kernels in the previous study. ELISA bioassays confirmed that the Bt protein could be transferred, but diluted through Bt maize-prey-predator. Life history parameters such as survival, development, weight, fecundity, and egg hatching rate were not significantly different when H. axyridis consumed prey that had been reared on Bt maize compared with prey reared on a nontransformed parental control. Furthermore, feeding directly on Bt maize pollen also had no detrimental effects on fitness, survival, and weight of female and male adults. In conclusion, our results indicate that transgenic cry1Ab/cry2Aj maize poses no ecological risks on the nontarget predator H. axyridis.
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Affiliation(s)
- Xue Chang
- State Key Laboratory of Rice Biology & Agricultural Entomology of Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
- Key Laboratory of Integrated Pest Management on Crops in Northeast of Ministry of Agriculture, Institute of Plant Protection, Jilin Academy of Agricultural Sciences, Gongzhuling 136100, China
| | - Zengbin Lu
- Maize Research Institute, Shandong Academy of Agricultural Sciences/National Engineering Laboratory of Wheat and Maize/Key Laboratory of Biology and Genetic Improvement of Maize in Northern Yellow-Huai River Plain, Ministry of Agriculture, Jinan 250100, China
| | - Zhicheng Shen
- State Key Laboratory of Rice Biology & Agricultural Entomology of Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yufa Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Gongyin Ye
- State Key Laboratory of Rice Biology & Agricultural Entomology of Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
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Wang ZX, Li YH, He KL, Bai SX, Zhang TT, Cai WZ, Wang ZY. Does Bt maize expressing Cry1Ac protein have adverse effects on the parasitoid Macrocentrus cingulum (Hymenoptera: Braconidae)? INSECT SCIENCE 2017; 24:599-612. [PMID: 27126195 DOI: 10.1111/1744-7917.12352] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 02/23/2016] [Accepted: 03/06/2016] [Indexed: 06/05/2023]
Abstract
The potential effects of insect-resistant, genetically engineered (GE) crops on non-target organisms, especially on predators and parasitoids, must be evaluated before their commercial cultivation. The effects of GE maize that produces Cry1Ac toxin on the parasitoid Macrocentrus cingulum were assessed by direct bioassay and indirect bioassay. In the indirect bioassay, parasitism rate, cocoon weight and the number of M. cingulum progeny produced per host were significantly reduced when M. cingulum-parasitized Cry1Ac-susceptible Ostrinia furnacalis were fed a diet containing purified Cry1Ac; however, life-table parameters of M. cingulum were not adversely affected when the same assay was performed with Cry1Ac-resistant O. furnacalis. These results indicated that the detrimental effects detected with a Cry1Ac-susceptible host were mediated by poor host quality. In a direct bioassay, no difference in life-table parameters were detected when M. cingulum adults were directly fed a 20% honey solution with or without Cry1Ac; however, survival and longevity were significantly reduced when M. cingulum adults were fed a honey solution containing potassium arsenate, which was used as a positive control. The stability and bioactivity of Cry1Ac toxin in the food sources and Cry1Ac toxin uptake by the host insect and parasitoid were confirmed by enzyme-linked immunosorbent assay and sensitive-insect bioassays. Our results demonstrate that M. cingulum is not sensitive to Cry1Ac toxin at concentrations exceeding those encountered in Bacillus thuringiensis maize fields. This study also demonstrates the power of using resistant hosts when assessing the risk of genetically modified plants on non-target organisms and will be useful for assessing other non-target impacts.
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Affiliation(s)
- Zeng-Xia Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, MOA - CABI Joint Laboratory for Bio-safety, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
- Department of Entomology, China Agriculture University, Beijing, China
| | - Yun-He Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, MOA - CABI Joint Laboratory for Bio-safety, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Kang-Lai He
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, MOA - CABI Joint Laboratory for Bio-safety, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Shu-Xiong Bai
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, MOA - CABI Joint Laboratory for Bio-safety, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Tian-Tao Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, MOA - CABI Joint Laboratory for Bio-safety, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Wan-Zhi Cai
- Department of Entomology, China Agriculture University, Beijing, China
| | - Zhen-Ying Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, MOA - CABI Joint Laboratory for Bio-safety, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
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Yalpani N, Altier D, Barry J, Kassa A, Nowatzki TM, Sethi A, Zhao JZ, Diehn S, Crane V, Sandahl G, Guan R, Poland B, Perez Ortega C, Nelson ME, Xie W, Liu L, Wu G. An Alcaligenes strain emulates Bacillus thuringiensis producing a binary protein that kills corn rootworm through a mechanism similar to Cry34Ab1/Cry35Ab1. Sci Rep 2017; 7:3063. [PMID: 28596570 PMCID: PMC5465095 DOI: 10.1038/s41598-017-03544-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 04/28/2017] [Indexed: 11/15/2022] Open
Abstract
Crops expressing Bacillus thuringiensis (Bt)-derived insecticidal protein genes have been commercially available for over 15 years and are providing significant value to growers. However, there remains the need for alternative insecticidal actives due to emerging insect resistance to certain Bt proteins. A screen of bacterial strains led to the discovery of a two-component insecticidal protein named AfIP-1A/1B from an Alcaligenes faecalis strain. This protein shows selectivity against coleopteran insects including western corn rootworm (WCR). Transgenic maize plants expressing AfIP-1A/1B demonstrate strong protection from rootworm injury. Surprisingly, although little sequence similarity exists to known insecticidal proteins, efficacy tests using WCR populations resistant to two different Cry proteins show that AfIP-1A/1B and mCry3A differ in their mode of action while AfIP-1A/1B and the binary Cry34Ab1/Cry35Ab1 protein share a similar mode. These findings are supported by results of competitive binding assays and the similarity of the x-ray structure of AfIP-1A to Cry34Ab1. Our work indicates that insecticidal proteins obtained from a non-Bt bacterial source can be useful for developing genetically modified crops and can function similarly to familiar proteins from Bt.
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Affiliation(s)
| | - Dan Altier
- DuPont Pioneer, Johnston, IA, 50131, USA
| | | | | | | | - Amit Sethi
- DuPont Pioneer, Johnston, IA, 50131, USA
| | | | | | | | | | - Rongjin Guan
- Nexomics Biosciences, Bordentown, NJ, 08505, USA
| | | | | | | | | | - Lu Liu
- DuPont Pioneer, Hayward, CA, 94545, USA
| | - Gusui Wu
- DuPont Pioneer, Johnston, IA, 50131, USA
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A Comprehensive Assessment of the Effects of Transgenic Cry1Ac/Cry1Ab Rice Huahui 1 on Adult Micraspis discolor (Fabricius) (Coleoptera: Coccinellidae). PLoS One 2016; 11:e0142714. [PMID: 26914608 PMCID: PMC4767879 DOI: 10.1371/journal.pone.0142714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 02/02/2016] [Indexed: 11/19/2022] Open
Abstract
Micraspis discolor (Fabricius) (Coleoptera: Coccinellidae) is a widely distributed coleoptera predator in southern Asia in rice ecosystem, and adult M. discolor feed on both rice pollen and soft-bodied arthropods. Bitrophic bioassay and tritrophic bioassay were conducted to evaluate the potential impact of Cry1Ac/Cry1Ab-expressing rice Huahui 1 and its non-transgenic counterpart Minghui 63 on fitness parameters of adult M. discolor. The results showed that the survival, and fecundity of this beetle’ adults were not different when they fed on Bt rice or non-Bt rice pollen or Nilaparvata lugens (Stål) reared on Bt rice or non-Bt rice. Toxicity assessment to ensure M. discolor adults were not sensitive to Cry1Ab or Cry1Ac protein independent from the pollen background, M. discolor adults were fed with an artificial diet containing Cry1Ac, Cry1Ab or both protein approximately 10 times higher concentration than in Huahui 1 rice pollen. No difference was detected for any of the life-table parameters tested between Cry protein-containing and pure diet. Artificial diet containing E-64 (N-(trans-Epoxysuccinyl)-L-leucine 4-guanidinobutylamide) was included as a positive control. In contrast, the pre-oviposition and fecundity of M. discolor were significantly adversely affected by feeding on E-64-containing diet. In both bioassays, the uptakes of Cry protein by adult M. discolor were tested by ELISA measurements. These results indicated that adults of M. discolor are not affected by Cry1Ab- or Cry1Ac-expressing rice pollen and are not sensitive to Cry protein at concentrations exceeding the levels in rice pollen in Huahui1. This suggests that M. discolor adults would not be harmed by Cry1Ac/Cry1Ab rice if Bt rice Huahui 1 were commercialized.
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Bt proteins Cry1Ah and Cry2Ab do not affect cotton aphid Aphis gossypii and ladybeetle Propylea japonica. Sci Rep 2016; 6:20368. [PMID: 26829252 PMCID: PMC4734323 DOI: 10.1038/srep20368] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 12/31/2015] [Indexed: 01/03/2023] Open
Abstract
Plant varieties expressing the Bt (Bacillus thuringiensis) insecticidal proteins Cry1Ah and Cry2Ab have potential commercialization prospects in China. However, their potential effects on non-target arthropods (NTAs) remain uncharacterized. The cotton aphid Aphis gossypii is a worldwide pest that damages various important crops. The ladybeetle Propylea japonica is a common and abundant natural enemy in many cropping systems in East Asia. In the present study, the effects of Cry1Ah and Cry2Ab proteins on A. gossypii and P. japonica were assessed from three aspects. First, neither of the Cry proteins affected the growth or developmental characteristics of the two test insects. Second, the expression levels of the detoxification-related genes of the two test insects did not change significantly in either Cry protein treatment. Third, neither of the Cry proteins had a favourable effect on the expression of genes associated with the amino acid metabolism of A. gossypii and the nutrition utilization of P. japonica. In conclusion, the Cry1Ah and Cry2Ab proteins do not appear to affect the cotton aphid A. gossypii or the ladybeetle P. japonica.
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Yang C, Pan H, Noland JE, Zhang D, Zhang Z, Liu Y, Zhou X. Selection of reference genes for RT-qPCR analysis in a predatory biological control agent, Coleomegilla maculata (Coleoptera: Coccinellidae). Sci Rep 2015; 5:18201. [PMID: 26656102 PMCID: PMC4674751 DOI: 10.1038/srep18201] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 11/13/2015] [Indexed: 01/11/2023] Open
Abstract
Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable technique for quantifying gene expression across various biological processes, of which requires a set of suited reference genes to normalize the expression data. Coleomegilla maculata (Coleoptera: Coccinellidae), is one of the most extensively used biological control agents in the field to manage arthropod pest species. In this study, expression profiles of 16 housekeeping genes selected from C. maculata were cloned and investigated. The performance of these candidates as endogenous controls under specific experimental conditions was evaluated by dedicated algorithms, including geNorm, Normfinder, BestKeeper, and ΔCt method. In addition, RefFinder, a comprehensive platform integrating all the above-mentioned algorithms, ranked the overall stability of these candidate genes. As a result, various sets of suitable reference genes were recommended specifically for experiments involving different tissues, developmental stages, sex, and C. maculate larvae treated with dietary double stranded RNA. This study represents the critical first step to establish a standardized RT-qPCR protocol for the functional genomics research in a ladybeetle C. maculate. Furthermore, it lays the foundation for conducting ecological risk assessment of RNAi-based gene silencing biotechnologies on non-target organisms; in this case, a key predatory biological control agent.
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Affiliation(s)
- Chunxiao Yang
- Hunan Academy of Agricultural Sciences, Institute of Plant Protection, Hunan, China
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | - Huipeng Pan
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | | | - Deyong Zhang
- Hunan Academy of Agricultural Sciences, Institute of Plant Protection, Hunan, China
| | - Zhanhong Zhang
- Hunan Vegetable Institute, Hunan Academy of Agricultural Sciences, Hunan, China
| | - Yong Liu
- Hunan Academy of Agricultural Sciences, Institute of Plant Protection, Hunan, China
| | - Xuguo Zhou
- Department of Entomology, University of Kentucky, Lexington, KY, USA
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Tay WT, Mahon RJ, Heckel DG, Walsh TK, Downes S, James WJ, Lee SF, Reineke A, Williams AK, Gordon KHJ. Insect Resistance to Bacillus thuringiensis Toxin Cry2Ab Is Conferred by Mutations in an ABC Transporter Subfamily A Protein. PLoS Genet 2015; 11:e1005534. [PMID: 26583651 PMCID: PMC4652872 DOI: 10.1371/journal.pgen.1005534] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 08/25/2015] [Indexed: 12/15/2022] Open
Abstract
The use of conventional chemical insecticides and bacterial toxins to control lepidopteran pests of global agriculture has imposed significant selection pressure leading to the rapid evolution of insecticide resistance. Transgenic crops (e.g., cotton) expressing the Bt Cry toxins are now used world wide to control these pests, including the highly polyphagous and invasive cotton bollworm Helicoverpa armigera. Since 2004, the Cry2Ab toxin has become widely used for controlling H. armigera, often used in combination with Cry1Ac to delay resistance evolution. Isolation of H. armigera and H. punctigera individuals heterozygous for Cry2Ab resistance in 2002 and 2004, respectively, allowed aspects of Cry2Ab resistance (level, fitness costs, genetic dominance, complementation tests) to be characterised in both species. However, the gene identity and genetic changes conferring this resistance were unknown, as was the detailed Cry2Ab mode of action. No cross-resistance to Cry1Ac was observed in mutant lines. Biphasic linkage analysis of a Cry2Ab-resistant H. armigera family followed by exon-primed intron-crossing (EPIC) marker mapping and candidate gene sequencing identified three independent resistance-associated INDEL mutations in an ATP-Binding Cassette (ABC) transporter gene we named HaABCA2. A deletion mutation was also identified in the H. punctigera homolog from the resistant line. All mutations truncate the ABCA2 protein. Isolation of further Cry2Ab resistance alleles in the same gene from field H. armigera populations indicates unequal resistance allele frequencies and the potential for Bt resistance evolution. Identification of the gene involved in resistance as an ABC transporter of the A subfamily adds to the body of evidence on the crucial role this gene family plays in the mode of action of the Bt Cry toxins. The structural differences between the ABCA2, and that of the C subfamily required for Cry1Ac toxicity, indicate differences in the detailed mode-of-action of the two Bt Cry toxins. Transgenic crops expressing the insecticidal protein Cry2Ab from Bacillus thuringiensis (Bt) are used worldwide to suppress damage by lepidopteran pests, often used in combination with Cry1Ac toxin to delay resistance evolution. Until now, the Cry2Ab mode of action and the mechanism of resistance were unknown, with field-isolated Cry2Ab resistant Helicoverpa armigera showing no cross-resistance to Cry1Ac. In this study, biphasic linkage analysis of a Cry2Ab-resistant H. armigera family followed by EPIC marker mapping and candidate gene sequencing identified three independent INDEL mutations in an ATP-Binding Cassette transporter subfamily A gene (ABCA2). A deletion mutation was identified in the same gene of resistant H. punctigera. All four mutations are predicted to truncate the ABCA2 protein. This is the first molecular genetic characterization of insect resistance to the Cry2Ab toxin, and detection of diverse Cry2Ab resistance alleles will contribute to understanding the micro-evolutionary processes that underpinned lepidopteran Bt-resistance.
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Affiliation(s)
- Wee Tek Tay
- CSIRO, Black Mountain Laboratories, Canberra, Australian Capital Territory, Australia
- * E-mail:
| | - Rod J. Mahon
- CSIRO, Black Mountain Laboratories, Canberra, Australian Capital Territory, Australia
| | - David G. Heckel
- Department of Entomology, Max-Planck Institute for Chemical Ecology, Beutenberg Campus, Jena, Germany
| | - Thomas K. Walsh
- CSIRO, Black Mountain Laboratories, Canberra, Australian Capital Territory, Australia
| | - Sharon Downes
- CSIRO, Australian Cotton Research Institute, Narrabri, New South Wales, Australia
| | - William J. James
- CSIRO, Black Mountain Laboratories, Canberra, Australian Capital Territory, Australia
| | - Sui-Fai Lee
- Department of Genetics, University of Melbourne, Parkville, Victoria, Australia
| | - Annette Reineke
- Institute for Phytomedicine, Center of Applied Biology, Geisenheim University, Geiesenheim, Germany
| | - Adam K. Williams
- Department of Genetics, University of Melbourne, Parkville, Victoria, Australia
| | - Karl H. J. Gordon
- CSIRO, Black Mountain Laboratories, Canberra, Australian Capital Territory, Australia
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Bt crops benefit natural enemies to control non-target pests. Sci Rep 2015; 5:16636. [PMID: 26559133 PMCID: PMC4642322 DOI: 10.1038/srep16636] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 10/16/2015] [Indexed: 11/26/2022] Open
Abstract
Crops producing insecticidal crystal (Cry) proteins from Bacillus thuringiensis (Bt) control important lepidopteran pests. However, pests such as aphids not susceptible to Cry proteins may require other integrated pest management (IPM) tactics, including biological control. We fed aphids on Bt and non-Bt plants and analyzed the Bt protein residue in aphids and compared the effects of Bt plants and a pyrethroid, lambda-cyhalothrin, on the performance of three natural enemies (predators: Coleomegilla maculata and Eupeodes americanus; parasitoid Aphidius colemani) of the green peach aphid, Myzus persicae. No Bt protein residues in aphids were detected and no significant differences were recorded in the performance of pyrethroid-resistant aphids that fed on Bt broccoli expressing Cry1Ab or Cry1C, or on non-Bt broccoli plants treated or not treated with the pyrethroid. This indicated the aphids were not affected by the Cry proteins or the pyrethroid, thus removing any effect of prey quality. Tri-trophic experiments demonstrated that no C. maculata and E. americanus survived consumption of pyrethroid-treated aphids and that ovipositional behavior of A. colemani was impaired when provided with pyrethroid-treated aphids. In contrast, natural enemies were not affected when fed aphids reared on Bt broccoli, thus demonstrating the safety of these Bt plants for IPM.
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The interaction of two-spotted spider mites, Tetranychus urticae Koch, with Cry protein production and predation by Amblyseius andersoni (Chant) in Cry1Ac/Cry2Ab cotton and Cry1F maize. Transgenic Res 2015; 25:33-44. [DOI: 10.1007/s11248-015-9917-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 10/31/2015] [Indexed: 11/25/2022]
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Muzaffar A, Kiani S, Khan MAU, Rao AQ, Ali A, Awan MF, Iqbal A, Nasir IA, Shahid AA, Husnain T. Chloroplast localization of Cry1Ac and Cry2A protein--an alternative way of insect control in cotton. Biol Res 2015; 48:14. [PMID: 25889424 PMCID: PMC4389580 DOI: 10.1186/s40659-015-0005-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 02/17/2015] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Insects have developed resistance against Bt-transgenic plants. A multi-barrier defense system to weaken their resistance development is now necessary. One such approach is to use fusion protein genes to increase resistance in plants by introducing more Bt genes in combination. The locating the target protein at the point of insect attack will be more effective. It will not mean that the non-green parts of the plants are free of toxic proteins, but it will inflict more damage on the insects because they are at maximum activity in the green parts of plants. RESULTS Successful cloning was achieved by the amplification of Cry2A, Cry1Ac, and a transit peptide. The appropriate polymerase chain reaction amplification and digested products confirmed that Cry1Ac and Cry2A were successfully cloned in the correct orientation. The appearance of a blue color in sections of infiltrated leaves after 72 hours confirmed the successful expression of the construct in the plant expression system. The overall transformation efficiency was calculated to be 0.7%. The amplification of Cry1Ac-Cry2A and Tp2 showed the successful integration of target genes into the genome of cotton plants. A maximum of 0.673 μg/g tissue of Cry1Ac and 0.568 μg/g tissue of Cry2A was observed in transgenic plants. We obtained 100% mortality in the target insect after 72 hours of feeding the 2nd instar larvae with transgenic plants. The appearance of a yellow color in transgenic cross sections, while absent in the control, through phase contrast microscopy indicated chloroplast localization of the target protein. CONCLUSION Locating the target protein at the point of insect attack increases insect mortality when compared with that of other transgenic plants. The results of this study will also be of great value from a biosafety point of view.
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Affiliation(s)
- Adnan Muzaffar
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
- Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan.
| | - Sarfraz Kiani
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Muhammad Azmat Ullah Khan
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Abdul Qayyum Rao
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Arfan Ali
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Mudassar Fareed Awan
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Adnan Iqbal
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Idrees Ahmad Nasir
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Ahmad Ali Shahid
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
| | - Tayyab Husnain
- National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, 53700, Pakistan.
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Consumption of Bt rice pollen containing Cry1C or Cry2A does not pose a risk to Propylea japonica (Thunberg) (Coleoptera: Coccinellidae). Sci Rep 2015; 5:7679. [PMID: 25567127 PMCID: PMC4286735 DOI: 10.1038/srep07679] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 12/03/2014] [Indexed: 11/16/2022] Open
Abstract
As a pollen feeder, Propylea japonica would be directly exposed to Cry proteins in Bacillus thuringiensis (Bt)-transgenic rice fields. The effect of Cry1C- or Cry2A-containing transgenic rice pollen on the fitness of P. japonica was assessed using two dietary-exposure experiments in the laboratory. In the first experiment, larval developmental time of P. japonica was significantly longer when fed pollen from Bt rice lines rather than control pollen but other life table parameters were not significantly affected. In the second experiment, P. japonica was not affected when fed a rapeseed pollen-based diet containing purified Cry1C or Cry2A at concentrations that were >10-times higher than in pollen, but P. japonica was affected when the diet contained E-64 as a positive control. In both experiments, the stability and bioactivity of the Cry proteins in the food sources and the uptake of the proteins by P. japonica were confirmed. The results show that P. japonica is not sensitive to Cry1C or Cry2A proteins; the effect observed in the first experiment was likely attributable to unknown differences in the nutritional composition of Bt rice pollen. Overall, the data indicate that the growing of Cry1C- or Cry2A-transgenic rice should pose a negligible risk to P. japonica.
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Wang ZX, Lin KJ, Romeis J, Liu YL, Liu ZW, Li YH, Peng YF. Use of a dietary exposure system for screening of insecticidal compounds for their toxicity to the planthopper Laodelphax striatellus. INSECT SCIENCE 2014; 21:667-675. [PMID: 24115524 DOI: 10.1111/1744-7917.12060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/12/2013] [Indexed: 06/02/2023]
Abstract
We developed a dietary exposure assay for screening insecticidal compounds for their toxicity and for assessing the side effects of insecticidal proteins produced by genetically engineered (GE) plants on the planthopper Laodelphax striatellus Fallén. The fitness bioassay confirmed that the diet fulfills the requirements to be used in the dietary exposure system. To validate the efficacy of the dietary exposure system, nymphs of L. striatellus were fed diets treated with different concentrations of an inorganic stomach poison, potassium arsenate (PA), or a cysteine protease inhibitor, E-64. The results showed that with increasing concentrations of E-64, the larval development time was prolonged, the adult weight was reduced and the survival rate of L. striatellus was decreased. Similarly the survival rates of L. striatellus consistently decreased with increasing PA content in the diet. The data indicate that the dietary exposure assay is able to detect the effects of insecticidal compounds on L. striatellus. Subsequently, this assay was successfully used for assessing the potential toxicity of Cry2Aa. The results showed that L. striatellus larvae were not negatively affected when fed the artificial diet containing purified Cry2Aa at 300 μg/g diet. In the assay, the stability and bioactivity of crystal (Cry) proteins in the food sources were confirmed by enzyme-linked immunosorbent assay and sensitive-insect bioassays. These results show that L. striatellus is not sensitive to Cry2Aa. We conclude that the dietary exposure system is valid and useful for assessing the toxicity of insecticidal compounds produced by GE plants on planthoppers.
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Affiliation(s)
- Zeng-Xia Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing; Nanjing Agricultural University, Nanjing, China
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Romeis J, Meissle M, Naranjo SE, Li Y, Bigler F. The end of a myth-Bt (Cry1Ab) maize does not harm green lacewings. FRONTIERS IN PLANT SCIENCE 2014; 5:391. [PMID: 25161661 PMCID: PMC4129496 DOI: 10.3389/fpls.2014.00391] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/22/2014] [Indexed: 06/01/2023]
Abstract
A concern with Bt-transgenic insect-resistant plants is their potential to harm non-target organisms. Early studies reported that Cry1Ab-producing Bt maize and purified Cry1Ab harmed larvae of the green lacewing, Chrysoperla carnea. Although these effects could not be confirmed in subsequent studies, some authors still refer to them as evidence that Bt maize harms beneficial species. We provide a comprehensive review of the studies evaluating the effects of Bt (Cry1Ab) maize on C. carnea. The evidence indicates that this important predator is not affected by Bt maize or by the produced Cry1Ab protein. We discuss how conceptual models can assist environmental risk assessments, and we emphasize the importance of robust and reproducible studies.
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Affiliation(s)
- Jörg Romeis
- Agroscope, Institute for Sustainability Sciences ISSZurich, Switzerland
| | - Michael Meissle
- Agroscope, Institute for Sustainability Sciences ISSZurich, Switzerland
| | | | - Yunhe Li
- Agroscope, Institute for Sustainability Sciences ISSZurich, Switzerland
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural SciencesBeijing, China
| | - Franz Bigler
- Agroscope, Institute for Sustainability Sciences ISSZurich, Switzerland
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Yu H, Romeis J, Li Y, Li X, Wu K. Acquisition of Cry1Ac protein by non-target arthropods in Bt soybean fields. PLoS One 2014; 9:e103973. [PMID: 25110881 PMCID: PMC4128818 DOI: 10.1371/journal.pone.0103973] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Accepted: 07/04/2014] [Indexed: 11/18/2022] Open
Abstract
Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.
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Affiliation(s)
- Huilin Yu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jörg Romeis
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Institute for Sustainability Sciences ISS, Agroscope, Zurich, Switzerland
| | - Yunhe Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiangju Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Kongming Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Wu H, Zhang Y, Liu P, Xie J, He Y, Deng C, De Clercq P, Pang H. Effects of transgenic Cry1Ac + CpTI cotton on non-target mealybug pest Ferrisia virgata and its predator Cryptolaemus montrouzieri. PLoS One 2014; 9:e95537. [PMID: 24751821 PMCID: PMC3994093 DOI: 10.1371/journal.pone.0095537] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 03/28/2014] [Indexed: 11/23/2022] Open
Abstract
Recently, several invasive mealybugs (Hemiptera: Pseudococcidae) have rapidly spread to Asia and have become a serious threat to the production of cotton including transgenic cotton. Thus far, studies have mainly focused on the effects of mealybugs on non-transgenic cotton, without fully considering their effects on transgenic cotton and trophic interactions. Therefore, investigating the potential effects of mealybugs on transgenic cotton and their key natural enemies is vitally important. A first study on the effects of transgenic cotton on a non-target mealybug, Ferrisia virgata (Cockerell) (Hemiptera: Pseudococcidae) was performed by comparing its development, survival and body weight on transgenic cotton leaves expressing Cry1Ac (Bt toxin) + CpTI (Cowpea Trypsin Inhibitor) with those on its near-isogenic non-transgenic line. Furthermore, the development, survival, body weight, fecundity, adult longevity and feeding preference of the mealybug predator Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) was assessed when fed F. virgata maintained on transgenic cotton. In order to investigate potential transfer of Cry1Ac and CpTI proteins via the food chain, protein levels in cotton leaves, mealybugs and ladybirds were quantified. Experimental results showed that F. virgata could infest this bivalent transgenic cotton. No significant differences were observed in the physiological parameters of the predator C. montrouzieri offered F. virgata reared on transgenic cotton or its near-isogenic line. Cry1Ac and CpTI proteins were detected in transgenic cotton leaves, but no detectable levels of both proteins were present in the mealybug or its predator when reared on transgenic cotton leaves. Our bioassays indicated that transgenic cotton poses a negligible risk to the predatory coccinellid C. montrouzieri via its prey, the mealybug F. virgata.
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Affiliation(s)
- Hongsheng Wu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Yuhong Zhang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Ping Liu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jiaqin Xie
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yunyu He
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Congshuang Deng
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Patrick De Clercq
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
- * E-mail: (HP); (PDC)
| | - Hong Pang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- * E-mail: (HP); (PDC)
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Li Y, Peng Y, Hallerman EM, Wu K. Biosafety management and commercial use of genetically modified crops in China. PLANT CELL REPORTS 2014; 33:565-573. [PMID: 24493253 DOI: 10.1007/s00299-014-1567-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Accepted: 01/09/2014] [Indexed: 06/03/2023]
Abstract
As a developing country with relatively limited arable land, China is making great efforts for development and use of genetically modified (GM) crops to boost agricultural productivity. Many GM crop varieties have been developed in China in recent years; in particular, China is playing a leading role in development of insect-resistant GM rice lines. To ensure the safe use of GM crops, biosafety risk assessments are required as an important part of the regulatory oversight of such products. With over 20 years of nationwide promotion of agricultural biotechnology, a relatively well-developed regulatory system for risk assessment and management of GM plants has been developed that establishes a firm basis for safe use of GM crops. So far, a total of seven GM crops involving ten events have been approved for commercial planting, and 5 GM crops with a total of 37 events have been approved for import as processing material in China. However, currently only insect-resistant Bt cotton and disease-resistant papaya have been commercially planted on a large scale. The planting of Bt cotton and disease-resistant papaya have provided efficient protection against cotton bollworms and Papaya ringspot virus (PRSV), respectively. As a consequence, chemical application to these crops has been significantly reduced, enhancing farm income while reducing human and non-target organism exposure to toxic chemicals. This article provides useful information for the colleagues, in particular for them whose mother tongue is not Chinese, to clearly understand the biosafety regulation and commercial use of genetically modified crops in China.
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Affiliation(s)
- Yunhe Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
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Li YH, Romeis J, Wu KM, Peng YF. Tier-1 assays for assessing the toxicity of insecticidal proteins produced by genetically engineered plants to non-target arthropods. INSECT SCIENCE 2014; 21:125-134. [PMID: 23956068 DOI: 10.1111/1744-7917.12044] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/21/2012] [Indexed: 06/02/2023]
Abstract
In assessing an insect-resistant genetically engineered (IRGE) crop before its commercialization, researchers normally use so-called "Tier-1 assays" as the initial step to determine the effects of the crop on non-target organisms. In these tests, the insecticidal proteins (IPs) produced by the IRGEs are added to the diets of test organisms in the laboratory. Test organisms in such assays can be directly exposed to much higher concentrations of the test IPs than they would encounter in the field. The results of Tier-1 assays are thus more conservative than those generated in studies in which the organisms are exposed to the IPs by feeding on IRGE plant tissue or in the case of predators or parasites, by feeding on invertebrate prey or hosts that have fed on IRGE plant tissue. In this report, we consider three important factors that must be considered in Tier-1 assays: (i) methods for delivery of the IP to the test organisms; (ii) the need for and selection of compounds used as positive controls; and (iii) methods for monitoring the concentration, stability and bioactivity of the IP during the assay. We also analyze the existing data from Tier-1 assays regarding the toxicity of Bt Cry proteins to non-target arthropod species. The data indicate that the widely used Bt proteins have no direct toxicity to non-target organisms.
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Affiliation(s)
- Yun-He Li
- State Key Laboratory for Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Tian JC, Long LP, Wang XP, Naranjo SE, Romeis J, Hellmich RL, Wang P, Shelton AM. Using resistant prey demonstrates that Bt plants producing Cry1Ac, Cry2Ab, and Cry1F have no negative effects on Geocoris punctipes and Orius insidiosus. ENVIRONMENTAL ENTOMOLOGY 2014; 43:242-251. [PMID: 24472212 DOI: 10.1603/en13184] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Geocoris punctipes (Say) and Orius insidiosus (Say) are generalist predators found in a wide range of crops, including cotton (Gossypium hirsutum L.) and maize (Zea mays L.), where they provide important biological control services by feeding on an array of pests, including eggs and small larvae of caterpillars. A high percentage of cotton and maize in the United States and several other countries are transgenic cultivars that produce one or more of the insecticidal Cry proteins of Bacillus thuringiensis Berliner (Bt). Here we quantify effects of three Cry proteins on the life history of these predators over two generations when they are exposed to these Cry proteins indirectly through their prey. To eliminate the confounding prey quality effects that can be introduced by Bt-susceptible prey, we used Cry1Ac/Cry2Ab-resistant Trichoplusia ni (Hübner) and Cry1 F-resistant Spodoptera frugiperda (J.E. Smith) in a series of tri-trophic studies. Survival, development, adult mass, fecundity, and fertility were similar when predators consumed larvae feeding on Cry1Ac/Cry2Ab cotton or Cry1 F maize compared with prey feeding on isogenic or near-isogenic cotton or maize. Repeated exposure of the same initial cohort over a second generation also resulted in no differences in life-history traits when feeding on non-Bt- or Bt-fed prey. Enzyme-linked immunosorbent assay showed that predators were exposed to Bt Cry proteins from their prey and that these proteins became increasingly diluted as they moved up the food chain. Results show a clear lack of effect of three common and widespread Cry proteins on these two important predator species. The use of resistant insects to eliminate prey quality effects provides a robust and meaningful assessment of exposure and hazard.
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Affiliation(s)
- Jun-Ce Tian
- Department of Entomology, Cornell University, New York State Agricultural Experiment Station (NYSAES), 630 W. North St., Geneva, NY 14456, USA
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Zhang X, Li Y, Romeis J, Yin X, Wu K, Peng Y. Use of a pollen-based diet to expose the ladybird beetle Propylea japonica to insecticidal proteins. PLoS One 2014; 9:e85395. [PMID: 24409328 PMCID: PMC3883695 DOI: 10.1371/journal.pone.0085395] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Accepted: 12/04/2013] [Indexed: 11/19/2022] Open
Abstract
A rape seed pollen-based diet was developed and found to be suitable for use in a dietary exposure assay for Propylea japonica. Using the diet, we established and validated a dietary exposure assay by using the protease inhibitor E-64 as positive control. Dose-dependent responses were documented for all observed life-table parameters of P. japonica including survival, pupation and eclosion rates, development time and adult weight. Results suggested that the dietary assay can detect the effects of insecticidal compounds on the survival and development of P. japonica. Using the established dietary assay, we subsequently tested the toxicity of Cry1Ab, Cry1Ac and Cry1F proteins that are expressed by transgenic maize, cotton or rice plants to P. japonica larvae. The diet containing E-64 was included as a positive control. Survival and development of P. japonica larvae were not adversely affected when the diet contained purified Cry1Ab, Cry1Ac, or Cry1F at 500 µg/g diet representing a worst-case exposure scenario. In contrast, P. japonica larvae were adversely affected when the diet contained E-64. The bioactivity and stability of the Cry proteins in the diet and Cry protein uptake by the ladybird larvae were confirmed by bioassay with a Cry-sensitive insect species and by ELISA. The current study describes a suitable experimental system for assessing the potential effects of gut-active insecticidal compounds on ladybird beetle larvae. The experiments with the Cry proteins demonstrate that P. japonica larvae are not sensitive to Cry1Ab, Cry1Ac and Cry1F.
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Affiliation(s)
- Xiaojie Zhang
- College of Life Science, Henan Agricultural University, Zhengzhou, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yunhe Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jörg Romeis
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Agroscope, Institute for Sustainability Sciences ISS, Zurich, Switzerland
| | - Xinming Yin
- College of Life Science, Henan Agricultural University, Zhengzhou, China
| | - Kongming Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yufa Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Li Y, Wang Y, Romeis J, Liu Q, Lin K, Chen X, Peng Y. Bt rice expressing Cry2Aa does not cause direct detrimental effects on larvae of Chrysoperla sinica. ECOTOXICOLOGY (LONDON, ENGLAND) 2013; 22:1413-21. [PMID: 24057602 DOI: 10.1007/s10646-013-1127-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/11/2013] [Indexed: 05/16/2023]
Abstract
To assess the potential effects of Cry2Aa-expressing insect-resistant Bt rice on Chrysoperla sinica larvae, we conducted two tritrophic bioassays using a non-target (Laodelphax striatellus) and a target herbivore (Chilo suppressalis) as prey. None of the tested life-table parameters of C. sinica did differ when fed with L. striatellus nymphs reared on either Bt or control rice plants. Similarly, C. sinica larval survival and development were not affected when fed C. suppressalis larvae that were reared on Cry2Aa-contained artificial diet compared to those fed control diet. However, the 7-day larval weight was significantly decreased in the Bt treatment and none of the C. sinica larvae developed to the adult stage. To clarify whether the observed effects were due to the direct toxicity of Cry2Aa or prey-quality mediated, we conducted a dietary exposure assay in which the toxicity of Cry2Aa to C. sinica larvae was tested. Potassium arsenate (PA) was included as a positive control. None of the tested life-table parameters of C. sinica was adversely affected when fed Cry2Aa at 500 μg/ml sucrose solution. In contrast, C. sinica larvae were adversely affected by feeding on sucrose solution containing PA. In the feeding assays, exposure of C. sinica larvae to Cry2Aa was confirmed by ELISA. Our results demonstrate that C. sinica larvae are not sensitive to Cry2Aa at concentrations exceeding the levels that the larvae may encounter in Bt rice fields. Consequently the detrimental effects observed in the tritrophic studies using Bt rice-fed C. suppressalis as prey can be attributed to the decreased prey quality due to the sensitivity of C. suppressalis larvae to Cry2Aa.
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Affiliation(s)
- Yunhe Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China,
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Xie C, Wang C, Wang X, Yang X. Two modified RNA extraction methods compatible with transcript profiling and gene expression analysis for cotton roots. Prep Biochem Biotechnol 2013; 43:500-11. [PMID: 23581784 DOI: 10.1080/10826068.2012.759967] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Efficient isolation of high-quality RNA is of prime importance for optimal transcript profiling results and further gene expression analysis. However, it is difficult for cotton roots because of lower-than-average RNA content and high content of polysaccharides, polyphenols, and other secondary metabolites. To develop simple and reliable protocols for high-quality RNA extraction from cotton roots for transcript profiling and gene expression analysis, some modifications were introduced to a reported plant RNA isolation protocol and a reagent kit method. Using method A, we successfully extracted high-quality RNA for transcript profiling from cotton roots. Gel electrophoresis analysis and polymerase chain reaction (PCR) assay indicated that RNA had good integrity without protein and genomic DNA contamination. Furthermore, the A260/280 (1.9) and A260/230 (1.6) ratios indicated that the isolated RNA was of high purity. Using method B, about 7 µg total RNA of high quality could be obtained from 0.1 g samples from cotton roots, which can be used for reverse-transcription (RT)-PCR and quantitative real-time RT-PCR. The two RNA extraction methods were used to investigate different gene expression of cotton roots (Gossypium hirsutum) infected by weak pathogenic Verticillium dahliae and the results showed they can satisfy the transcript profiling and quantitative real-time RT-PCR requirements for RNA. Supplemental materials are available for this article. Go to the publisher's online edition of Preparative Biochemistry and Biotechnology to view the supplemental file.
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Affiliation(s)
- Chengjian Xie
- College of Life Science, Chongqing Normal University, Chongqing, China
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Tian JC, Wang XP, Long LP, Romeis J, Naranjo SE, Hellmich RL, Wang P, Earle ED, Shelton AM. Bt crops producing Cry1Ac, Cry2Ab and Cry1F do not harm the green lacewing, Chrysoperla rufilabris. PLoS One 2013; 8:e60125. [PMID: 23544126 PMCID: PMC3609736 DOI: 10.1371/journal.pone.0060125] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 02/22/2013] [Indexed: 11/21/2022] Open
Abstract
The biological control function provided by natural enemies is regarded as a protection goal that should not be harmed by the application of any new pest management tool. Plants producing Cry proteins from the bacterium, Bacillus thuringiensis (Bt), have become a major tactic for controlling pest Lepidoptera on cotton and maize and risk assessment studies are needed to ensure they do not harm important natural enemies. However, using Cry protein susceptible hosts as prey often compromises such studies. To avoid this problem we utilized pest Lepidoptera, cabbage looper (Trichoplusia ni) and fall armyworm (Spodoptera frugiperda), that were resistant to Cry1Ac produced in Bt broccoli (T. ni), Cry1Ac/Cry2Ab produced in Bt cotton (T. ni), and Cry1F produced in Bt maize (S. frugiperda). Larvae of these species were fed Bt plants or non-Bt plants and then exposed to predaceous larvae of the green lacewing Chrysoperla rufilabris. Fitness parameters (larval survival, development time, fecundity and egg hatch) of C. rufilabris were assessed over two generations. There were no differences in any of the fitness parameters regardless if C. rufilabris consumed prey (T. ni or S. frugiperda) that had consumed Bt or non-Bt plants. Additional studies confirmed that the prey contained bioactive Cry proteins when they were consumed by the predator. These studies confirm that Cry1Ac, Cry2Ab and Cry1F do not pose a hazard to the important predator C. rufilabris. This study also demonstrates the power of using resistant hosts when assessing the risk of genetically modified plants on non-target organisms.
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Affiliation(s)
- Jun-Ce Tian
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), Geneva, New York, United States of America
- State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Xiang-Ping Wang
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), Geneva, New York, United States of America
- College of Agriculture, Yangtze University, Jingzhou, Hubei, China
| | - Li-Ping Long
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), Geneva, New York, United States of America
- Rice Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Jörg Romeis
- Agroscope Reckenholz-Tänikon Research Station ART, Zürich, Switzerland
| | - Steven E. Naranjo
- USDA-ARS, Arid Land Agricultural Research Center, Maricopa, Arizona, United States of America
| | - Richard L. Hellmich
- USDA–ARS, Corn Insects and Crop Genetics Research Unit and Department of Entomology, Iowa State University, Ames, Iowa, United States of America
| | - Ping Wang
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), Geneva, New York, United States of America
| | - Elizabeth D. Earle
- Department of Plant Breeding and Genetics, Cornell University, Ithaca, New York, United States of America
| | - Anthony M. Shelton
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), Geneva, New York, United States of America
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Tian JC, Collins HL, Romeis J, Naranjo SE, Hellmich RL, Shelton AM. Using field-evolved resistance to Cry1F maize in a lepidopteran pest to demonstrate no adverse effects of Cry1F on one of its major predators. Transgenic Res 2012; 21:1303-10. [PMID: 22373893 PMCID: PMC3505541 DOI: 10.1007/s11248-012-9604-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 02/19/2012] [Indexed: 11/12/2022]
Abstract
Spodoptera frugiperda (JE Smith) represents the first documented case of field-evolved resistance to a genetically engineered crop expressing an insecticidal protein from Bacillus thuringiensis (Bt). In this case it was Cry1F-expressing maize (Mycogen 2A517). The ladybird beetle, Coleomegilla maculata, is a common and abundant predator that suppresses pest populations in maize and many other cropping systems. Its larvae and adults are polyphagous, feeding on aphids, thrips, lepidopteran eggs and larvae, as well as plant tissues. Thus, C. maculata may be exposed to Bt proteins expressed in genetically engineered crops by several pathways. Using Cry1F-resistant S. frugiperda larvae as prey, we evaluated the potential impact of Cry1F-expressing maize on several fitness parameters of C. maculata over two generations. Using Cry1F resistant prey removed any potential prey-mediated effects. Duration of larval and pupal stages, adult weight and female fecundity of C. maculata were not different when they were fed resistant S. frugiperda larvae reared on either Bt or control maize leaves during both generations. ELISA and insect-sensitive bioassays showed C. maculata were exposed to bioactive Cry1F protein. The insecticidal protein had no effect on C. maculata larvae, even though larvae contained 20-32 ng of Cry1F/g by fresh weight. Over all, our results demonstrated that the Cry1F protein did not affect important fitness parameters of one of S. frugiperda's major predators and that Cry1F protein did not accumulate but was strongly diluted when transferred during trophic interactions.
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Affiliation(s)
- Jun-Ce Tian
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), 630 West North Street, Geneva, NY 14456 USA
| | - Hilda L. Collins
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), 630 West North Street, Geneva, NY 14456 USA
| | - Jörg Romeis
- Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstr. 191, 8046 Zurich, Switzerland
| | - Steven E. Naranjo
- USDA-ARS, Arid Land Agricultural Research Center, 21881 North Cardon Lane, Maricopa, AZ 85138 USA
| | - Richard L. Hellmich
- Department of Entomology, USDA–ARS, Corn Insects and Crop Genetics Research Unit, Iowa State University, 110 Genetics Laboratory c/o Insectary, Ames, IA 50011 USA
| | - Anthony M. Shelton
- Department of Entomology, Cornell University/New York State Agricultural Experiment Station (NYSAES), 630 West North Street, Geneva, NY 14456 USA
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Dutra CC, Koch RL, Burkness EC, Meissle M, Romeis J, Hutchison WD, Fernandes MG. Harmonia axyridis (Coleoptera: Coccinellidae) exhibits no preference between Bt and non-Bt maize fed Spodoptera frugiperda (Lepidoptera: Noctuidae). PLoS One 2012; 7:e44867. [PMID: 23024772 PMCID: PMC3443105 DOI: 10.1371/journal.pone.0044867] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/09/2012] [Indexed: 11/18/2022] Open
Abstract
A recent shift in managing insect resistance to genetically engineered (GE) maize consists of mixing non-GE seed with GE seed known as "refuge in a bag", which increases the likelihood of predators encountering both prey fed Bt and prey fed non-Bt maize. We therefore conducted laboratory choice-test feeding studies to determine if a predator, Harmonia axyridis, shows any preference between prey fed Bt and non-Bt maize leaves. The prey species was Spodoptera frugiperda, which were fed Bt maize (MON-810), expressing the single Cry1Ab protein, or non-Bt maize. The predators were third instar larvae and female adults of H. axyridis. Individual predators were offered Bt and non-Bt fed prey larvae that had fed for 24, 48 or 72 h. Ten and 15 larvae of each prey type were offered to third instar and adult predators, respectively. Observations of arenas were conducted at 1, 2, 3, 6, 15 and 24 h after the start of the experiment to determine the number and type of prey eaten by each individual predator. Prey larvae that fed on non-Bt leaves were significantly larger than larvae fed Bt leaves. Both predator stages had eaten nearly all the prey by the end of the experiment. However, in all combinations of predator stage and prey age, the number of each prey type consumed did not differ significantly. ELISA measurements confirmed the presence of Cry1Ab in leaf tissue (23-33 µg/g dry weight) and S. frugiperda (2.1-2.2 µg/g), while mean concentrations in H. axyridis were very low (0.01-0.2 µg/g). These results confirm the predatory status of H. axyridis on S. frugiperda and that both H. axyridis adults and larvae show no preference between prey types. The lack of preference between Bt-fed and non-Bt-fed prey should act in favor of insect resistance management strategies using mixtures of GE and non-GE maize seed.
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Affiliation(s)
- Carla C. Dutra
- Faculdade de Ciências Agrárias, Universidade Federal da Grande Dourados, Dourados, Brazil
| | - Robert L. Koch
- Plant Protection Division, Minnesota Department of Agriculture, Saint Paul, Minnesota, United States of America
| | - Eric C. Burkness
- Department of Entomology, University of Minnesota, St. Paul, Minnesota, United States of America
| | - Michael Meissle
- Agroscope Reckenholz-Tänikon Research Station ART, Zurich, Switzerland
| | - Joerg Romeis
- Agroscope Reckenholz-Tänikon Research Station ART, Zurich, Switzerland
| | - William D. Hutchison
- Department of Entomology, University of Minnesota, St. Paul, Minnesota, United States of America
- * E-mail:
| | - Marcos G. Fernandes
- Faculdade de Ciências Biológicas e Ambientais, Universidade Federal da Grande Dourados, Dourados, Brazil
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Mc Lean M. A review of the environmental safety of the Cry1Ab protein. ENVIRONMENTAL BIOSAFETY RESEARCH 2012; 10:51-71. [PMID: 22541994 DOI: 10.1051/ebr:2012003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Morven Mc Lean
- Center for Environmental Risk Assessment, ILSI Research Foundation
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