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Zhao Y, Kim JY, Karan R, Jung JH, Pathak B, Williamson B, Kannan B, Wang D, Fan C, Yu W, Dong S, Srivastava V, Altpeter F. Generation of a selectable marker free, highly expressed single copy locus as landing pad for transgene stacking in sugarcane. PLANT MOLECULAR BIOLOGY 2019; 100:247-263. [PMID: 30919152 DOI: 10.1007/s11103-019-00856-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 03/15/2019] [Indexed: 05/23/2023]
Abstract
A selectable marker free, highly expressed single copy locus flanked by insulators was created as landing pad for transgene stacking in sugarcane. These events displayed superior transgene expression compared to single-copy transgenic lines lacking insulators. Excision of the selectable marker gene from transgenic sugarcane lines was supported by FLPe/FRT site-specific recombination. Sugarcane, a tropical C4 grass in the genus Saccharum (Poaceae), accounts for nearly 80% of sugar produced worldwide and is also an important feedstock for biofuel production. Generating transgenic sugarcane with predictable and stable transgene expression is critical for crop improvement. In this study, we generated a highly expressed single copy locus as landing pad for transgene stacking. Transgenic sugarcane lines with stable integration of a single copy nptII expression cassette flanked by insulators supported higher transgene expression along with reduced line to line variation when compared to single copy events without insulators by NPTII ELISA analysis. Subsequently, the nptII selectable marker gene was efficiently excised from the sugarcane genome by the FLPe/FRT site-specific recombination system to create selectable marker free plants. This study provides valuable resources for future gene stacking using site-specific recombination or genome editing tools.
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Affiliation(s)
- Yang Zhao
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
| | - Jae Y Kim
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
- Department of Plant Resources, College of Industrial Science, Kongju National University, Yesan, 32439, Republic of Korea
| | - Ratna Karan
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
| | - Je H Jung
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
- Smart Farm Research Center, Institute of Natural Products, Korea Institute of Science and Technology (KIST), Gangwon-do, 25451, Republic of Korea
| | - Bhuvan Pathak
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
| | - Bruce Williamson
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
| | - Baskaran Kannan
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Florida - IFAS, Gainesville, FL, 32611, USA
| | - Duoduo Wang
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Florida - IFAS, Gainesville, FL, 32611, USA
| | - Chunyang Fan
- Syngenta Crop Protection, LLC, Research Triangle Park, NC, 27709, USA
| | - Wenjin Yu
- Syngenta Crop Protection, LLC, Research Triangle Park, NC, 27709, USA
| | - Shujie Dong
- Syngenta Crop Protection, LLC, Research Triangle Park, NC, 27709, USA
| | - Vibha Srivastava
- Crop, Soil and Environmental Sciences, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Fredy Altpeter
- Agronomy Department, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida - IFAS, Gainesville, FL, 32611, USA.
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Florida - IFAS, Gainesville, FL, 32611, USA.
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Zhou D, Liu X, Gao S, Guo J, Su Y, Ling H, Wang C, Li Z, Xu L, Que Y. Foreign cry1Ac gene integration and endogenous borer stress-related genes synergistically improve insect resistance in sugarcane. BMC PLANT BIOLOGY 2018; 18:342. [PMID: 30526526 PMCID: PMC6288918 DOI: 10.1186/s12870-018-1536-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 11/19/2018] [Indexed: 05/10/2023]
Abstract
BACKGROUND Sugarcane (Saccharum spp. hybrids) is considered the most globally important sugar-producing crop and raw material for biofuel. Insect attack is a major issue in sugarcane cultivation, resulting in yield losses and sucrose content reductions. Stem borer (Diatraea saccharalis F.) causes serious yield losses in sugarcane worldwide. However, insect-resistant germplasms for sugarcane are not available in any collections all over the world, and the molecular mechanism of insect resistance has not been elucidated. In this study, cry1Ac transgenic sugarcane lines were obtained and the biological characteristics and transgene dosage effect were investigated and a global exploration of gene expression by transcriptome analysis was performed. RESULTS The transgene copies of foreign cry1Ac were variable and random. The correlation between the cry1Ac protein and cry1Ac gene copies differed between the transgenic lines from FN15 and ROC22. The medium copy lines from FN15 showed a significant linear relationship, while ROC22 showed no definite dosage effect. The transgenic lines with medium copies of cry1Ac showed an elite phenotype. Transcriptome analysis by RNA sequencing indicated that up/down regulated differentially expressed genes were abundant among the cry1Ac sugarcane lines and the receptor variety. Foreign cry1Ac gene and endogenous borer stress-related genes may have a synergistic effect. Three lines, namely, A1, A5, and A6, were selected for their excellent stem borer resistance and phenotypic traits and are expected to be used directly as cultivars or crossing parents for sugarcane borer resistance breeding. CONCLUSIONS Cry1Ac gene integration dramatically improved sugarcane insect resistance. The elite transgenic offspring contained medium transgene copies. Foreign cry1Ac gene integration and endogenous borer stress-related genes may have a synergistic effect on sugarcane insect resistance improvement.
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Affiliation(s)
- Dinggang Zhou
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
- Key Laboratory of Ecological Remediation and Safe Utilization of Heavy Metal-Polluted Soils, Hunan University of Science and Technology, School of Life Science, Xiangtan, 411201 Hunan China
| | - Xiaolan Liu
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
- Key Laboratory of Ecological Remediation and Safe Utilization of Heavy Metal-Polluted Soils, Hunan University of Science and Technology, School of Life Science, Xiangtan, 411201 Hunan China
| | - Shiwu Gao
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
| | - Jinlong Guo
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
| | - Yachun Su
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
| | - Hui Ling
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
| | - Chunfeng Wang
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
| | - Zhu Li
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
| | - Liping Xu
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
| | - Youxiong Que
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Fujian Agriculture and Forestry University, Ministry of Agriculture, Fuzhou, 350002 Fujian China
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Basso MF, da Cunha BADB, Ribeiro AP, Martins PK, de Souza WR, de Oliveira NG, Nakayama TJ, Augusto das Chagas Noqueli Casari R, Santiago TR, Vinecky F, Cançado LJ, de Sousa CAF, de Oliveira PA, de Souza SACD, Cançado GMDA, Kobayashi AK, Molinari HBC. Improved Genetic Transformation of Sugarcane (Saccharum spp.) Embryogenic Callus Mediated by Agrobacterium tumefaciens. ACTA ACUST UNITED AC 2018; 2:221-239. [PMID: 31725972 DOI: 10.1002/cppb.20055] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sugarcane (Saccharum spp.) is a monocotyledonous semi-perennial C4 grass of the Poaceae family. Its capacity to accumulate high content of sucrose and biomass makes it one of the most important crops for sugar and biofuel production. Conventional methods of sugarcane breeding have shown several limitations due to its complex polyploid and aneuploid genome. However, improvement by biotechnological engineering is currently the most promising alternative to introduce economically important traits. In this work, we present an improved protocol for Agrobacterium tumefaciens-mediated transformation of commercial sugarcane hybrids using immature top stalk-derived embryogenic callus cultures. The callus cultures are transformed with preconditioned A. tumefaciens carrying a binary vector that encodes expression cassettes for a gene of interest and the bialaphos resistance gene (bar confers resistance to glufosinate-ammonium herbicide). This protocol has been used to successfully transform a commercial sugarcane cultivar, SP80-3280, highlighting: (i) reduced recalcitrance and oxidation; (ii) high yield of embryogenic callus; (iii) improved selection; and (iv) shoot regeneration and rooting of the transformed plants. Altogether, these improvements generated a transformation efficiency of 2.2%. This protocol provides a reliable tool for a routine procedure for sugarcane improvement by genetic engineering. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Marcos Fernando Basso
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Bárbara Andrade Dias Brito da Cunha
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Ana Paula Ribeiro
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Polyana Kelly Martins
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Wagner Rodrigo de Souza
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Nelson Geraldo de Oliveira
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Thiago Jonas Nakayama
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Raphael Augusto das Chagas Noqueli Casari
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Thais Ribeiro Santiago
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Felipe Vinecky
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Letícia Jungmann Cançado
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Carlos Antônio Ferreira de Sousa
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Patricia Abrão de Oliveira
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | | | - Geraldo Magela de Almeida Cançado
- The Joint Research Unit for Genomics Applied to Climate Change (UMIP GenClima), National Center for Agricultural Informatics (CNPTIA), Brazilian Agricultural Research Corporation (EMBRAPA), Campinas, São Paulo, Brazil
| | - Adilson Kenji Kobayashi
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
| | - Hugo Bruno Correa Molinari
- Genetics and Biotechnology Laboratory, National Center for Agroenergy Research (CNPAE), Brazilian Agricultural Research Corporation (EMBRAPA), Brasília, Distrito Federal, Brazil
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Bhatia R, Gallagher JA, Gomez LD, Bosch M. Genetic engineering of grass cell wall polysaccharides for biorefining. PLANT BIOTECHNOLOGY JOURNAL 2017; 15:1071-1092. [PMID: 28557198 PMCID: PMC5552484 DOI: 10.1111/pbi.12764] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 05/17/2017] [Accepted: 05/24/2017] [Indexed: 05/10/2023]
Abstract
Grasses represent an abundant and widespread source of lignocellulosic biomass, which has yet to fulfil its potential as a feedstock for biorefining into renewable and sustainable biofuels and commodity chemicals. The inherent recalcitrance of lignocellulosic materials to deconstruction is the most crucial limitation for the commercial viability and economic feasibility of biomass biorefining. Over the last decade, the targeted genetic engineering of grasses has become more proficient, enabling rational approaches to modify lignocellulose with the aim of making it more amenable to bioconversion. In this review, we provide an overview of transgenic strategies and targets to tailor grass cell wall polysaccharides for biorefining applications. The bioengineering efforts and opportunities summarized here rely primarily on (A) reprogramming gene regulatory networks responsible for the biosynthesis of lignocellulose, (B) remodelling the chemical structure and substitution patterns of cell wall polysaccharides and (C) expressing lignocellulose degrading and/or modifying enzymes in planta. It is anticipated that outputs from the rational engineering of grass cell wall polysaccharides by such strategies could help in realizing an economically sustainable, grass-derived lignocellulose processing industry.
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Affiliation(s)
- Rakesh Bhatia
- Institute of Biological, Environmental and Rural Sciences (IBERS)Aberystwyth UniversityAberystwythUK
| | - Joe A. Gallagher
- Institute of Biological, Environmental and Rural Sciences (IBERS)Aberystwyth UniversityAberystwythUK
| | | | - Maurice Bosch
- Institute of Biological, Environmental and Rural Sciences (IBERS)Aberystwyth UniversityAberystwythUK
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Jung JH, Altpeter F. TALEN mediated targeted mutagenesis of the caffeic acid O-methyltransferase in highly polyploid sugarcane improves cell wall composition for production of bioethanol. PLANT MOLECULAR BIOLOGY 2016; 92:131-42. [PMID: 27306903 PMCID: PMC4999463 DOI: 10.1007/s11103-016-0499-y] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 05/30/2016] [Indexed: 05/18/2023]
Abstract
Sugarcane (Saccharum spp. hybrids) is a prime crop for commercial biofuel production. Advanced conversion technology utilizes both, sucrose accumulating in sugarcane stems as well as cell wall bound sugars for commercial ethanol production. Reduction of lignin content significantly improves the conversion of lignocellulosic biomass into ethanol. Conventional mutagenesis is not expected to confer reduction in lignin content in sugarcane due to its high polyploidy (x = 10-13) and functional redundancy among homo(eo)logs. Here we deploy transcription activator-like effector nuclease (TALEN) to induce mutations in a highly conserved region of the caffeic acid O-methyltransferase (COMT) of sugarcane. Capillary electrophoresis (CE) was validated by pyrosequencing as reliable and inexpensive high throughput method for identification and quantitative characterization of TALEN mediated mutations. Targeted COMT mutations were identified by CE in up to 74 % of the lines. In different events 8-99 % of the wild type COMT were converted to mutant COMT as revealed by pyrosequencing. Mutation frequencies among mutant lines were positively correlated to lignin reduction. Events with a mutation frequency of 99 % displayed a 29-32 % reduction of the lignin content compared to non-transgenic controls along with significantly reduced S subunit content and elevated hemicellulose content. CE analysis displayed similar peak patterns between primary COMT mutants and their vegetative progenies suggesting that TALEN mediated mutations were faithfully transmitted to vegetative progenies. This is the first report on genome editing in sugarcane. The findings demonstrate that targeted mutagenesis can improve cell wall characteristics for production of lignocellulosic ethanol in crops with highly complex genomes.
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Affiliation(s)
- Je Hyeong Jung
- Agronomy Department, University of Florida, IFAS, PO Box 110300, Gainesville, FL, 32611, USA
- Institute of Life Science and Natural Resources, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Fredy Altpeter
- Agronomy Department, University of Florida, IFAS, PO Box 110300, Gainesville, FL, 32611, USA.
- Plant Molecular and Cellular Biology Program, University of Florida, IFAS, PO Box 110300, Gainesville, FL, 32611, USA.
- Agronomy Department, University of Florida-IFAS, PO Box 103610, Gainesville, FL, 32611, USA.
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Romão-Dumaresq AS, Dourado MN, Fávaro LCDL, Mendes R, Ferreira A, Araújo WL. Diversity of Cultivated Fungi Associated with Conventional and Transgenic Sugarcane and the Interaction between Endophytic Trichoderma virens and the Host Plant. PLoS One 2016; 11:e0158974. [PMID: 27415014 PMCID: PMC4944904 DOI: 10.1371/journal.pone.0158974] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/24/2016] [Indexed: 12/23/2022] Open
Abstract
Plant-associated fungi are considered a vast source for biotechnological processes whose potential has been poorly explored. The interactions and diversity of sugarcane, one of the most important crops in Brazil, have been rarely studied, mainly concerning fungal communities and their interactions with transgenic plants. Taking this into consideration, the purpose of this study was, based on culture dependent strategy, to determine the structure and diversity of the fungal community (root endophytes and rhizosphere) associated with two varieties of sugarcane, a non-genetically modified (SP80-1842) variety and its genetically modified counterpart (IMI-1, expressing imazapyr herbicide resistance). For this, the sugarcane varieties were evaluated in three sampling times (3, 10 and 17 months after planting) under two crop management (weeding and herbicide treatments). In addition, a strain of Trichoderma virens, an endophyte isolated from sugarcane with great potential as a biological control, growth promotion and enzyme production agent, was selected for the fungal-plant interaction assays. The results of the isolation, characterization and evaluation of fungal community changes showed that the sugarcane fungal community is composed of at least 35 different genera, mostly in the phylum Ascomycota. Many genera are observed at very low frequencies among a few most abundant genera, some of which were isolated from specific plant sites (e.g., the roots or the rhizosphere). An assessment of the possible effects upon the fungal community showed that the plant growth stage was the only factor that significantly affected the community's structure. Moreover, if transgenic effects are present, they may be minor compared to other natural sources of variation. The results of interaction studies using the Green fluorescent protein (GFP)-expressing T. virens strain T.v.223 revealed that this fungus did not promote any phenotypic changes in the host plant and was found mostly in the roots where it formed a dense mycelial cover and was able to penetrate the intercellular spaces of the root epidermis upper layers. The ability of T. virens to colonize plant roots suggests a potential for protecting plant health, inhibiting pathogens or inducing systemic resistance.
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Affiliation(s)
- Aline Silva Romão-Dumaresq
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
| | - Manuella Nóbrega Dourado
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Léia Cecilia de Lima Fávaro
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, Brasília, Distrito Federal, Brazil
| | - Rodrigo Mendes
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Environment, Jaguariuna, São Paulo, Brazil
| | - Anderson Ferreira
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Agrosilvopastoral, Sinop, Mato Grosso, Brazil
| | - Welington Luiz Araújo
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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