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Krishna GV, Kumar VM, Varma PK, Bhavani B, Kumar GV. Detection of Sugarcane bacilliform virus in diseased sugarcane plants in Andhra Pradesh, India by serological and molecular methods. Braz J Microbiol 2023; 54:1399-1409. [PMID: 37580513 PMCID: PMC10485194 DOI: 10.1007/s42770-023-01094-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 08/03/2023] [Indexed: 08/16/2023] Open
Abstract
Sugarcane leaf fleck incited by Sugarcane bacilliform virus is emerging as a major disease and affecting exchange of sugarcane germplasm and cultivation worldwide. Roving surveys conducted in 162 fields belonging to 81 villages spread over 14 sugarcane growing districts of Andhra Pradesh during 2021-2022 revealed 8 to 44% incidence of the disease. Mean maximum fleck disease incidence was reported in Anakapalli district (33.00%) followed by Srikakulam district (22.66%), whereas least incidence was observed in Alluri Sitharamaraju district (9.33%). The early and sensitive detection of pathogens is vital and necessary to reduce the danger of introducing new diseases or pathogen strains into sugarcane growing regions. Both serological and molecular methods were used in proposed investigation to identify the virus at the protein and nucleic acid levels. DAS-ELISA results were positive for 50 suspected SCBV infected sugarcane leaf samples out of 81, with mean absorbance (A405) values ranging from 0.50 to 2.20. Further PCR assays were performed using SCBV-specific primers targeting RT/RNase H coding region which is frequently employed as a taxonomic marker for species delineation in Badnaviruses. Out of 81 symptomatic samples collected, 61 samples gave positive results, and no amplification was observed in healthy control and negative control. Results made it evident that PCR was more sensitive than DAS-ELISA. Low virus concentration or variation in virus strains may be the reason for the low detection rate in DAS-ELISA in the current study. Extensive roving surveys conducted for the incidence of leaf fleck disease for the first time in the state of Andhra Pradesh revealed severe occurrence of leaf fleck disease under field conditions.
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Affiliation(s)
- G Vamsi Krishna
- Department of Plant Pathology, Agricultural College, Bapatla, Acharya N.G Ranga Agricultural University, Guntur, Andhra Pradesh, India.
| | - V Manoj Kumar
- Department of Plant Pathology, Agricultural College, Bapatla, Acharya N.G Ranga Agricultural University, Guntur, Andhra Pradesh, India
| | - P Kishore Varma
- Department of Plant Pathology, Regional Agricultural Research Station, Lam, Guntur, Andhra Pradesh, India
| | - B Bhavani
- Department of Entomology, DAATT Centre, Amalapuram, Acharya N.G Ranga Agricultural University, Guntur, Andhra Pradesh, India
| | - G Vijaya Kumar
- Department of Crop Physiology, Agricultural College, Bapatla, Acharya N.G Ranga Agricultural University, Guntur, Andhra Pradesh, India
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Ishwara Bhat A, Selvarajan R, Balasubramanian V. Emerging and Re-Emerging Diseases Caused by Badnaviruses. Pathogens 2023; 12:pathogens12020245. [PMID: 36839517 PMCID: PMC9963457 DOI: 10.3390/pathogens12020245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/27/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
New and emerging plant diseases are caused by different pathogens including viruses that often cause significant crop losses. Badnaviruses are pararetroviruses that contain a single molecule of ds DNA genome of 7 to 9 kb in size and infect a large number of economically important crops such as banana and plantains, black pepper, cacao, citrus, grapevine, pineapple, sugarcane, sweet potato, taro, and yam, causing significant yield losses. Many of the species in the genus have a restricted host range and several of them are known to infect a single crop. Combined infections of different virus species and strains offer conditions that favor the development of new strains via recombination, especially in vegetatively propagated crops. The primary spread of badnaviruses is through vegetative propagating materials while for the secondary spread, they depend on insects such as mealybugs and aphids. Disease emerges as a consequence of the interactions between host and pathogens under favorable environmental conditions. The viral genome of the pararetroviruses is known to be integrated into the chromosome of the host and a few plants with integrants when subjected to different kinds of abiotic stress will give rise to episomal forms of the virus and cause disease. Attempts have been made to develop management strategies for badnaviruses both conventionally and using precision breeding techniques such as genome editing. Until 2016 only 32 badnavirus species infecting different crops were known, but in a span of six years, this number has gone up to 68. The current review highlights the emerging disease problems and management options for badnaviruses infecting economically important crops.
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Affiliation(s)
- Alangar Ishwara Bhat
- Division of Crop Protection, ICAR-Indian Institute of Spices Research, Kozhikode 673012, Kerala, India
| | - Ramasamy Selvarajan
- Division of Crop Protection, ICAR-National Research Centre for Banana, Trichy 620102, Tamil Nadu, India
| | - Velusamy Balasubramanian
- Division of Crop Protection, ICAR-National Research Centre for Banana, Trichy 620102, Tamil Nadu, India
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Janiga PK, Nithya K, Viswanathan R. Dynamics of Genetic Diversity Among Indian Sugarcane Bacilliform Virus Species and Implications of Associated Recombination Events in the Virus. SUGAR TECH 2022. [DOI: 10.1007/s12355-022-01224-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Ashraf MA, Feng X, Hu X, Ashraf F, Shen L, Iqbal MS, Zhang S. In silico identification of sugarcane (Saccharum officinarum L.) genome encoded microRNAs targeting sugarcane bacilliform virus. PLoS One 2022; 17:e0261807. [PMID: 35051194 PMCID: PMC8775236 DOI: 10.1371/journal.pone.0261807] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 12/10/2021] [Indexed: 12/12/2022] Open
Abstract
Sugarcane bacilliform virus (SCBV) is considered one of the most economically damaging pathogens for sugarcane production worldwide. Three open reading frames (ORFs) are characterized in the circular, ds-DNA genome of the SCBV; these encode for a hypothetical protein (ORF1), a DNA binding protein (ORF2), and a polyprotein (ORF3). A comprehensive evaluation of sugarcane (Saccharum officinarum L.) miRNAs for the silencing of the SCBV genome using in silico algorithms were carried out in the present study using mature sugarcane miRNAs. miRNAs of sugarcane are retrieved from the miRBase database and assessed in terms of hybridization with the SCBV genome. A total of 14 potential candidate miRNAs from sugarcane were screened out by all used algorithms used for the silencing of SCBV. The consensus of three algorithms predicted the hybridization site of sof-miR159e at common locus 5534. miRNA-mRNA interactions were estimated by computing the free-energy of the miRNA-mRNA duplex using the RNAcofold algorithm. A regulatory network of predicted candidate miRNAs of sugarcane with SCBV-ORFs, generated using Circos-is used to identify novel targets. The predicted data provide useful information for the development of SCBV-resistant sugarcane plants.
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Affiliation(s)
- Muhammad Aleem Ashraf
- Institute of Tropical Bioscience and Biotechnology, Sugarcane Research Centre of Chinese Academy of Tropical Agricultural Sciences, Haikou, China
- Department of Bioscience and Technology, Khwaja Fareed University of Engineering and Information Technology, Rahim Yar Khan, Pakistan
- * E-mail: (MAA); (SZ)
| | - Xiaoyan Feng
- Institute of Tropical Bioscience and Biotechnology, Sugarcane Research Centre of Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Xiaowen Hu
- Zhanjiang Experimental Station, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, China
| | - Fakiha Ashraf
- Institute of Tropical Bioscience and Biotechnology, Sugarcane Research Centre of Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Linbo Shen
- Institute of Tropical Bioscience and Biotechnology, Sugarcane Research Centre of Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | | | - Shuzhen Zhang
- Institute of Tropical Bioscience and Biotechnology, Sugarcane Research Centre of Chinese Academy of Tropical Agricultural Sciences, Haikou, China
- * E-mail: (MAA); (SZ)
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Parameswari B, Nithya K, Kumar S, Holkar SK, Chabbra ML, Kumar P, Viswanathan R. Genome wide association studies in sugarcane host pathogen system for disease resistance: an update on the current status of research. INDIAN PHYTOPATHOLOGY 2021. [DOI: 10.1007/s42360-021-00323-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Petersen SM, Keith C, Austin K, Howard S, Su L, Qiu W. A Natural Reservoir and Transmission Vector of Grapevine Vein Clearing Virus. PLANT DISEASE 2019; 103:571-577. [PMID: 30484754 DOI: 10.1094/pdis-06-18-1073-re] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Grapevine vein clearing virus (GVCV) is associated with a vein-clearing and vine-decline disease. In this study, we surveyed wild Ampelopsis cordata from the Vitaceae family and found that 31% (35 of 113) of native A. cordata plants are infected with GVCV. The full-length genome sequence of one GVCV isolate from A. cordata shared 99.8% identical nucleotides with an isolate from a nearby cultivated 'Chardonel' grapevine, suggesting the occurrence of an insect vector. To identify a vector, we collected Aphis illinoisensis (common name: grape aphids) from wild A. cordata plants and detected GVCV in the aphid populations. We found that A. illinoisensis is capable of transmitting GVCV from infected A. cordata to Chardonel grapevines in the greenhouse. Upon transmission, GVCV caused severe symptoms on the infected Chardonel 45 days post transmission. We conclude that wild GVCV isolates from A. cordata are capable of inducing a severe disease on cultivated grapevines once they spread from native A. cordata to vineyards via grape aphids. The discovery of a natural reservoir and an insect vector of GVCV provides timely knowledge for disease management in vineyards and critical clues on viral evolution and epidemiology.
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Affiliation(s)
- Sylvia M Petersen
- Center for Grapevine Biotechnology, William H. Darr College of Agriculture, Missouri State University, Mountain Grove, MO 65711
| | - Cory Keith
- Center for Grapevine Biotechnology, William H. Darr College of Agriculture, Missouri State University, Mountain Grove, MO 65711
| | - Kaylie Austin
- Center for Grapevine Biotechnology, William H. Darr College of Agriculture, Missouri State University, Mountain Grove, MO 65711
| | - Susanne Howard
- Center for Grapevine Biotechnology, William H. Darr College of Agriculture, Missouri State University, Mountain Grove, MO 65711
| | - Li Su
- Center for Grapevine Biotechnology, William H. Darr College of Agriculture, Missouri State University, Mountain Grove, MO 65711
| | - Wenping Qiu
- Center for Grapevine Biotechnology, William H. Darr College of Agriculture, Missouri State University, Mountain Grove, MO 65711
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Ahmad K, Sun SR, Chen JL, Huang MT, Fu HY, Gao SJ. Presence of Diverse Sugarcane Bacilliform Viruses Infecting Sugarcane in China Revealed by Pairwise Sequence Comparisons and Phylogenetic Analysis. THE PLANT PATHOLOGY JOURNAL 2019; 35:41-50. [PMID: 30828278 PMCID: PMC6385652 DOI: 10.5423/ppj.oa.08.2018.0156] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 09/16/2018] [Accepted: 10/04/2018] [Indexed: 06/09/2023]
Abstract
Sugarcane bacilliform viruses (SCBV), which belong to the genus Badnavirus, family Caulimoviridae, are an important DNA virus complex that infects sugarcane. To explore the genetic diversity of the sugarcane-infecting badnavirus complex in China, we tested 392 sugarcane leaf samples collected from Fujian, Yunnan, and Hainan provinces for the occurrence of SCBV by polymerase chain reaction (PCR) assays using published primers SCBV-F and SCBV-R that target the reverse transcriptase/ribonuclease H (RT/RNase H) regions of the viral genome. A total of 111 PCR-amplified fragments (726 bp) from 63 SCBV-positive samples were cloned and sequenced. A neighbor-joining phylogenetic tree was constructed based on the SCBV sequences from this study and 34 published sequences representing 18 different phylogroups or genotypes (SCBV-A to -R). All SCBV-tested isolates could be classified into 20 SCBV phylogenetic groups from SCBV-A to -T. Of nine SCBV phylogroups reported in this study, two novel phylogroups, SCBV-S and SCBV-T, that share 90.0-93.2% sequence identity and show 0.07-0.11 genetic distance with each other in the RT/ RNase H region, are proposed. SCBV-S had 57.6-92.2% sequence identity and 0.09-0.66 genetic distance, while SCBV-T had 58.4-90.0% sequence identity and 0.11-0.63 genetic distance compared with the published SCBV phylogroups. Additionally, two other Badnavirus species, Sugarcane bacilliform MO virus (SCBMOV) and Sugarcane bacilliform IM virus (SCBIMV), which originally clustered in phylogenetic groups SCBV-E and SCBV-F, respectively, are first reported in China. Our findings will help to understand the level of genetic heterogeneity present in the complex of Badnavirus species that infect sugarcane.
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Affiliation(s)
- Kashif Ahmad
- National Engineering Research Center of Sugarcane, Fujian Agricultural and Forestry University, Fuzhou 350002,
China
| | - Sheng-Ren Sun
- National Engineering Research Center of Sugarcane, Fujian Agricultural and Forestry University, Fuzhou 350002,
China
| | - Jun-Lü Chen
- Guangzhou Sugarcane Industry Research Institute, Guangzhou 510316, Guangdong,
China
| | - Mei-Ting Huang
- National Engineering Research Center of Sugarcane, Fujian Agricultural and Forestry University, Fuzhou 350002,
China
| | - Hua-Ying Fu
- National Engineering Research Center of Sugarcane, Fujian Agricultural and Forestry University, Fuzhou 350002,
China
| | - San-Ji Gao
- National Engineering Research Center of Sugarcane, Fujian Agricultural and Forestry University, Fuzhou 350002,
China
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Development of Quantitative Real-Time PCR Assays for Rapid and Sensitive Detection of Two Badnavirus Species in Sugarcane. BIOMED RESEARCH INTERNATIONAL 2018; 2018:8678242. [PMID: 30175148 PMCID: PMC6106854 DOI: 10.1155/2018/8678242] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 07/11/2018] [Accepted: 07/15/2018] [Indexed: 11/30/2022]
Abstract
Sugarcane-infecting badnaviruses (sugarcane bacilliform viruses, SCBVs) represent a genetically heterogeneous species complex, posing a serious threat to the yield and quality of sugarcane in all major producing regions. SCBVs are commonly transmitted across regions by the exchange of sugarcane germplasm. In this study, we develop two quick, sensitive, and reliable protocols for real-time quantitative PCR (qPCR) of Sugarcane bacilliform MO virus (SCBMOV) and Sugarcane bacilliform IM virus (SCBIMV) using two sets of TaqMan probes and primers targeting the reverse transcriptase/ribonuclease H (RT/RNase H) region. The two assays had a detection limit of 100 copies of plasmid DNA and were 100 times more sensitive than conventional PCR. High specificity of the two assays was observed with respect to SCBIMV and SCBMOV. A total of 176 sugarcane leaf tissue samples from Fujian and Yunnan provinces were collected and analyzed in parallel by conventional PCR, SCBIMV-qPCR, and SCBMOV-qPCR. The SCBIMV-qPCR and SCBMOV-qPCR assays indicated that 50% (88/176) and 47% (83/176) samples tested positive, respectively, whereas only 29% (51/176) tested positive with conventional PCR with the primer pairs SCBV-F and SCBV-R. We demonstrate for the first time that SCBIMV and SCBMOV occur in China and reveal coinfection of both Badnavirus species in 29% (51/176) of tested leaf samples. Our findings supply sensitive and reliable qPCR assays for the detection and quantitation of SCBV in sugarcane quarantine programs.
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Gao SJ, Damaj MB, Park JW, Wu XB, Sun SR, Chen RK, Mirkov TE. A novel Sugarcane bacilliform virus promoter confers gene expression preferentially in the vascular bundle and storage parenchyma of the sugarcane culm. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:172. [PMID: 28680479 PMCID: PMC5496340 DOI: 10.1186/s13068-017-0850-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 06/16/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Saccharum species such as sugarcane and energy cane are key players in the expanding bioeconomy for sugars, bioenergy, and production of high-value proteins. Genomic tools such as culm-regulated promoters would be of great value in terms of improving biomass characteristics through enhanced carbon metabolism for sugar accumulation and/or fiber content for biofuel feedstock. Unlike the situation in dicots, monocot promoters currently used are limited and mostly derived from highly expressed constitutive plant genes and viruses. In this study, a novel promoter region of Sugarcane bacilliform virus (SCBV; genus Badnavirus, family Caulimoviridae), SCBV21 was cloned and mapped by deletion analysis and functionally characterized transiently in monocot and dicot species and stably in sugarcane. RESULTS In silico analysis of SCBV21 [1816 base pair (bp)] identified two putative promoter regions (PPR1 and PPR2) with transcription start sites (TSS1 and TSS2) and two TATA-boxes (TATAAAT and ATATAA), and several vascular-specific and regulatory elements. Deletion analysis revealed that the 710 bp region spanning PPR2 (with TSS2 and ATATAA) at the 3' end of SCBV21 retained the full promoter activity in both dicots and monocots, as shown by transient expression of the enhanced yellow fluorescent protein (EYFP) gene. In sugarcane young leaf segments, SCBV21 directed a 1.8- and 2.4-fold higher transient EYFP expression than the common maize ubiquitin 1 (Ubi1) and Cauliflower mosaic virus 35S promoters, respectively. In transgenic sugarcane, SCBV21 conferred a preferential expression of the β-glucuronidase (GUS) gene in leaves and culms and specifically in the culm storage parenchyma surrounding the vascular bundle and in vascular phloem cells. Among the transgenic events and tissues characterized in this study, the SCBV21 promoter frequently produced higher GUS activity than the Ubi1 or 35S promoters in a manner that was not obviously correlated with the transgene copy number. CONCLUSIONS The newly developed plant viral SCBV21 promoter is distinct from the few existing SCBV promoters in its sequence and expression pattern. The potential of SCBV21 as a tissue-regulated promoter with a strong activity in the culm vascular bundle and its storage parenchyma makes it useful in sugarcane engineering for improved carbon metabolism, increased bioenergy production, and enhanced stress tolerance.
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Affiliation(s)
- San-Ji Gao
- National Engineering Research Center for Sugarcane, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian China
| | | | | | - Xiao-Bin Wu
- Guangdong Key Lab of Sugarcane Improvement & Biorefinery, Guangzhou Sugarcane Industry Research Institute, Guangzhou, 510316 Guangdong China
| | - Sheng-Ren Sun
- National Engineering Research Center for Sugarcane, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian China
| | - Ru-Kai Chen
- National Engineering Research Center for Sugarcane, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian China
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Bhat AI, Hohn T, Selvarajan R. Badnaviruses: The Current Global Scenario. Viruses 2016; 8:E177. [PMID: 27338451 PMCID: PMC4926197 DOI: 10.3390/v8060177] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 05/18/2016] [Accepted: 05/25/2016] [Indexed: 12/16/2022] Open
Abstract
Badnaviruses (Family: Caulimoviridae; Genus: Badnavirus) are non-enveloped bacilliform DNA viruses with a monopartite genome containing about 7.2 to 9.2 kb of dsDNA with three to seven open reading frames. They are transmitted by mealybugs and a few species by aphids in a semi-persistent manner. They are one of the most important plant virus groups and have emerged as serious pathogens affecting the cultivation of several horticultural crops in the tropics, especially banana, black pepper, cocoa, citrus, sugarcane, taro, and yam. Some badnaviruses are also known as endogenous viruses integrated into their host genomes and a few such endogenous viruses can be awakened, e.g., through abiotic stress, giving rise to infective episomal forms. The presence of endogenous badnaviruses poses a new challenge for the fool-proof diagnosis, taxonomy, and management of the diseases. The present review aims to highlight emerging disease problems, virus characteristics, transmission, and diagnosis of badnaviruses.
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Affiliation(s)
| | - Thomas Hohn
- UNIBAS, Botanical Institute, 4056 Basel, Switzerland.
| | - Ramasamy Selvarajan
- ICAR-National Research Centre for Banana, Tiruchirapalli 620102, Tamil Nadu, India.
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Molecular Diagnostics and Application of DNA Markers in the Management of Major Diseases of Sugarcane. Fungal Biol 2016. [DOI: 10.1007/978-3-319-27312-9_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Sharma SK, Vignesh Kumar P, Geetanjali AS, Pun KB, Baranwal VK. Subpopulation level variation of banana streak viruses in India and common evolution of banana and sugarcane badnaviruses. Virus Genes 2015; 50:450-65. [PMID: 25672291 DOI: 10.1007/s11262-015-1179-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Accepted: 01/31/2015] [Indexed: 01/21/2023]
Abstract
Genome sequences of three episomal Banana streak MY virus (BSMYV) isolates sampled from triploid banana hybrids (Chini Champa: AAB; Malbhog: AAB and Monthan: ABB), grown in North-East and South India are reported in this study by sequence-independent improved rolling circle amplification (RCA). RCA coupled with restriction fragment length polymorphism revealed diverse restriction profiles of five BSMYV isolates. Nucleotide substitution rates of BSMYV subpopulation and Banana streak OL virus subpopulation was 7.13 × 10(-3) to 1.59 × 10(-2) and 2.65 × 10(-3) to 5.49 × 10(-3), respectively, for the different coding regions. Analysis of the genetic diversity of banana and sugarcane badnaviruses revealed a total of 32 unique recombination events among banana and sugarcane badnaviruses (inter BSV-SCBV), in addition to the extensive recombination with in banana streak viruses and sugarcane bacilliform viruses (intra-BSV and intra-SCBV). Many unique fragments were shown to contain similar ruminant sequence fragments which indicated the possibility that the two groups of badnaviruses or their ancestors to colonise same host before making the host shift. The distribution of recombination events, hot-spots (intergenic region and C-terminal of ORF3) as well as cold-spots (distributed in ORF3) displayed the mirroring of recombination traces in both group of badnaviruses. These results support the hypothesis of relatedness of banana and sugarcane badnaviruses and the host and geographical shifts that followed the fixation of the species complex appear to be a recent event.
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Affiliation(s)
- Susheel Kumar Sharma
- Advanced Centre for Plant Virology, Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
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