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Wang Y, Guo Y, Guo S, Qi L, Li B, Jiang L, Xu C, An M, Wu Y. RNA interference-based exogenous double-stranded RNAs confer resistance to Rhizoctonia solani AG-3 on Nicotiana tabacum. PEST MANAGEMENT SCIENCE 2024; 80:2170-2178. [PMID: 38284497 DOI: 10.1002/ps.7962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 12/22/2023] [Accepted: 12/26/2023] [Indexed: 01/30/2024]
Abstract
BACKGROUND Rhizoctonia solani Kühn is a pathogenic fungus causing tobacco target spot disease, and leads to great losses worldwide. At present, resistant varieties and effective control strategy on tobacco target spot disease are very limited. Host-induced gene silencing (HIGS) as well as the exogenous dsRNA can be used to suppress disease progression, and reveal the function of crucial genes involved in the growth and pathogenesis of the fungus. RESULTS The silencing of endoPGs or RPMK1 in host plants by TRV-based HIGS resulted in a significant reduction in disease development in Nicotiana benthamiana. In vitro analysis validated that red fluorescence signals were consistently observed in the hyphae treated with Cy3-fluorescein-labeled dsRNA at 12, 24, 48 and 72 h postinoculation (hpi). Additionally, application of dsRNA-endoPGs, dsRNA-RPMK1 and dsRNA-PGMK (fusion of partial endoPGs and RPMK1 sequences) effectively inhibited the hyphal growth of R. solani YC-9 in vitro and suppressed disease progression in the leaves, and quantitative real-time PCR confirmed that the application of dsRNAs significantly reduced the expression levels of endoPGs and RPMK1. CONCLUSION These results provide theoretical basis and new direction for RNAi approaches on the prevention and control of disease caused by R. solani. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Yan Wang
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Yi Guo
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Shiping Guo
- Sichuan Province Tobacco Company, Chengdu, China
| | - Lin Qi
- Sichuan Province Tobacco Company, Chengdu, China
| | - Bin Li
- Sichuan Province Tobacco Company, Chengdu, China
| | - Lianqiang Jiang
- Liangshanzhou Branch of Sichuan Province Tobacco Company, Xichang, China
| | - Chuantao Xu
- Luzhou Branch of Sichuan Province Tobacco Company, Luzhou, China
| | - Mengnan An
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Yuanhua Wu
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
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Zhang D, Lin R, Yamamoto N, Wang Z, Lin H, Okada K, Liu Y, Xiang X, Zheng T, Zheng H, Yi X, Noutoshi Y, Zheng A. Mitochondrial-targeting effector RsIA_CtaG/Cox11 in Rhizoctonia solani AG-1 IA has two functions: plant immunity suppression and cell death induction mediated by a rice cytochrome c oxidase subunit. MOLECULAR PLANT PATHOLOGY 2024; 25:e13397. [PMID: 37902589 PMCID: PMC10799210 DOI: 10.1111/mpp.13397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 09/24/2023] [Accepted: 09/29/2023] [Indexed: 10/31/2023]
Abstract
Rhizoctonia solani AG-1 IA causes a necrotrophic rice disease and is a serious threat to rice production. To date, only a few effectors have been characterized in AG-1 IA. We previously identified RsIA_CtaG/Cox11 and showed that infiltration of the recombinant protein into rice leaves caused disease-like symptoms. In the present study, we further characterized the functionality of RsIA_CtaG/Cox11. RsIA_CtaG/Cox11 is an alternative transcript of cytochrome c oxidase copper chaperone Cox11 that starts from the second AUG codon, but contains a functional secretion signal peptide. RNA interference with RsIA_CtaG/Cox11 reduced the pathogenicity of AG-1 IA towards rice and Nicotiana benthamiana without affecting its fitness or mycelial morphology. Transient expression of the RsIA_CtaG/Cox11-GFP fusion protein demonstrated the localization of RsIA_CtaG/Cox11 to mitochondria. Agro-infiltration of RsIA_CtaG/Cox11 into N. benthamiana leaves inhibited cell death by BAX and INF1. In contrast to rice, agro-infiltration of RsIA_CtaG/Cox11 did not induce cell death in N. benthamiana. However, cell death was observed when it was coinfiltrated with Os_CoxVIIa, which encodes a subunit of cytochrome c oxidase. Os_CoxVIIa appeared to interact with RsIA_CtaG/Cox11. The cell death triggered by coexpression of RsIA_CtaG/Cox11 and Os_CoxVIIa is independent of the leucine-rich repeat receptor kinases BAK1/SOBIR1 and enhanced the susceptibility of N. benthamiana to AG-1 IA. Two of the three evolutionarily conserved cysteine residues at positions 25 and 126 of RsIA_CtaG/Cox11 were essential for its immunosuppressive activity, but not for cell death induction. This report suggests that RsIA_CtaG/Cox11 appears to have a dual role in immunosuppression and cell death induction during pathogenesis.
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Affiliation(s)
- Danhua Zhang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest ChinaChengduChina
- School of AgronomySichuan Agricultural UniversityChengduChina
| | - Runmao Lin
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests Ministry of EducationHainan UniversityHaikouChina
| | - Naoki Yamamoto
- School of AgronomySichuan Agricultural UniversityChengduChina
| | - Zhaoyilin Wang
- Rice Research InstituteSichuan Agricultural UniversityChengduChina
| | - Hui Lin
- School of AgronomySichuan Agricultural UniversityChengduChina
| | - Kazunori Okada
- Agro‐Biotechnology Research CenterThe University of TokyoTokyoJapan
| | - Yao Liu
- Key Laboratory of Sichuan Province, Crop Research InstituteSichuan Academy of Agricultural SciencesChengduChina
| | - Xing Xiang
- School of AgronomySichuan Agricultural UniversityChengduChina
| | - Tengda Zheng
- School of AgronomySichuan Agricultural UniversityChengduChina
| | | | - Xiaoqun Yi
- School of AgronomySichuan Agricultural UniversityChengduChina
| | - Yoshiteru Noutoshi
- Graduate School of Environmental, Life, and Natural Science and TechnologyOkayama UniversityOkayamaJapan
| | - Aiping Zheng
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest ChinaChengduChina
- School of AgronomySichuan Agricultural UniversityChengduChina
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Zhang YQ, Song XY, Liu F. XanFur, a novel Fur protein induced by H 2O 2, positively regulated by the global transcriptional regulator Clp and required for the full virulence of Xanthomonas oryzae pv. oryzae in rice. Microbiol Spectr 2023; 11:e0118723. [PMID: 37831462 PMCID: PMC10714925 DOI: 10.1128/spectrum.01187-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 08/07/2023] [Indexed: 10/14/2023] Open
Abstract
IMPORTANCE Although Xanthomonas oryzae pv. oryzae (Xoo) has been found to be a bacterial pathogen causing bacterial leaf blight in rice for many years, the molecular mechanisms of the rice-Xoo interaction has not been fully understood. In this study, we found that XanFur of Xoo is a novel ferric uptake regulator (Fur) protein conserved among major pathogenic Xanthomonas species. XanFur is required for the virulence of Xoo in rice, and likely involved in regulating the virulence determinants of Xoo. The expression of xanfur is induced by H2O2, and positively regulated by the global transcriptional regulator Clp. Our results reveal the function and regulation of the novel virulence-related Fur protein XanFur in Xoo, providing new insights into the interaction mechanisms of rice-Xoo.
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Affiliation(s)
- Yu-Qiang Zhang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu, China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, China
| | - Xiao-Yan Song
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, China
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu, China
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McLaughlin MS, Roy M, Abbasi PA, Carisse O, Yurgel SN, Ali S. Why Do We Need Alternative Methods for Fungal Disease Management in Plants? PLANTS (BASEL, SWITZERLAND) 2023; 12:3822. [PMID: 38005718 PMCID: PMC10675458 DOI: 10.3390/plants12223822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/03/2023] [Accepted: 11/07/2023] [Indexed: 11/26/2023]
Abstract
Fungal pathogens pose a major threat to food production worldwide. Traditionally, chemical fungicides have been the primary means of controlling these pathogens, but many of these fungicides have recently come under increased scrutiny due to their negative effects on the health of humans, animals, and the environment. Furthermore, the use of chemical fungicides can result in the development of resistance in populations of phytopathogenic fungi. Therefore, new environmentally friendly alternatives that provide adequate levels of disease control are needed to replace chemical fungicides-if not completely, then at least partially. A number of alternatives to conventional chemical fungicides have been developed, including plant defence elicitors (PDEs); biological control agents (fungi, bacteria, and mycoviruses), either alone or as consortia; biochemical fungicides; natural products; RNA interference (RNAi) methods; and resistance breeding. This article reviews the conventional and alternative methods available to manage fungal pathogens, discusses their strengths and weaknesses, and identifies potential areas for future research.
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Affiliation(s)
- Michael S. McLaughlin
- Agriculture and Agri-Food Canada, Kentville Research and Development Centre, Kentville, NS B4N 1J5, Canada; (M.S.M.); (M.R.); (P.A.A.)
- Department of Plant, Food and Environmental Sciences, Faculty of Agriculture, Dalhousie University, Truro, NS B2N 4H5, Canada
| | - Maria Roy
- Agriculture and Agri-Food Canada, Kentville Research and Development Centre, Kentville, NS B4N 1J5, Canada; (M.S.M.); (M.R.); (P.A.A.)
- Department of Biology, Acadia University, Wolfville, NS B4P 2R6, Canada
| | - Pervaiz A. Abbasi
- Agriculture and Agri-Food Canada, Kentville Research and Development Centre, Kentville, NS B4N 1J5, Canada; (M.S.M.); (M.R.); (P.A.A.)
| | - Odile Carisse
- Saint-Jean-sur-Richelieu Research Development Centre, Science and Technology Branch, Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu, QC J3B 7B5, Canada;
| | - Svetlana N. Yurgel
- United States Department of Agriculture (USDA), Agricultural Research Service, Grain Legume Genetics and Physiology Research Unit, Prosser, WA 99350, USA;
| | - Shawkat Ali
- Agriculture and Agri-Food Canada, Kentville Research and Development Centre, Kentville, NS B4N 1J5, Canada; (M.S.M.); (M.R.); (P.A.A.)
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Qin L, Nong J, Cui K, Tang X, Gong X, Xia Y, Xu Y, Qiu Y, Li X, Xia S. SsCak1 Regulates Growth and Pathogenicity in Sclerotinia sclerotiorum. Int J Mol Sci 2023; 24:12610. [PMID: 37628791 PMCID: PMC10454577 DOI: 10.3390/ijms241612610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/07/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Sclerotinia sclerotiorum is a devastating fungal pathogen that causes severe crop losses worldwide. It is of vital importance to understand its pathogenic mechanism for disease control. Through a forward genetic screen combined with next-generation sequencing, a putative protein kinase, SsCak1, was found to be involved in the growth and pathogenicity of S. sclerotiorum. Knockout and complementation experiments confirmed that deletions in SsCak1 caused defects in mycelium and sclerotia development, as well as appressoria formation and host penetration, leading to complete loss of virulence. These findings suggest that SsCak1 is essential for the growth, development, and pathogenicity of S. sclerotiorum. Therefore, SsCak1 could serve as a potential target for the control of S. sclerotiorum infection through host-induced gene silencing (HIGS), which could increase crop resistance to the pathogen.
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Affiliation(s)
- Lei Qin
- Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha 410128, China; (L.Q.); (J.N.); (X.T.); (X.G.); (Y.X.)
| | - Jieying Nong
- Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha 410128, China; (L.Q.); (J.N.); (X.T.); (X.G.); (Y.X.)
| | - Kan Cui
- Institute of Plant Protection, Hunan Academy of Agricultural Sciences, Changsha 410125, China;
| | - Xianyu Tang
- Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha 410128, China; (L.Q.); (J.N.); (X.T.); (X.G.); (Y.X.)
| | - Xin Gong
- Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha 410128, China; (L.Q.); (J.N.); (X.T.); (X.G.); (Y.X.)
| | - Yunong Xia
- Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha 410128, China; (L.Q.); (J.N.); (X.T.); (X.G.); (Y.X.)
| | - Yan Xu
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada;
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Yilan Qiu
- Department of Life Science, Hunan Normal University, Changsha 410081, China;
| | - Xin Li
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada;
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Shitou Xia
- Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha 410128, China; (L.Q.); (J.N.); (X.T.); (X.G.); (Y.X.)
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Nanosheet-Facilitated Spray Delivery of dsRNAs Represents a Potential Tool to Control Rhizoctonia solani Infection. Int J Mol Sci 2022; 23:ijms232112922. [DOI: 10.3390/ijms232112922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 10/18/2022] [Accepted: 10/21/2022] [Indexed: 11/16/2022] Open
Abstract
Rhizoctonia solani is one of the important pathogenic fungi causing several serious crop diseases, such as maize and rice sheath blight. Current methods used to control the disease mainly depend on spraying fungicides because there is no immunity or high resistance available in crops. Spraying double-strand RNA (dsRNA) for induced-gene silencing (SIGS) is a new potentially sustainable and environmentally friendly tool to control plant diseases. Here, we found that fluorescein-labelled EGFP-dsRNA could be absorbed by R. solani in co-incubation. Furthermore, three dsRNAs, each targeting one of pathogenicity-related genes, RsPG1, RsCATA, and RsCRZ1, significantly downregulated the transcript levels of the target genes after co-incubation, leading to a significant reduction in the pathogenicity of the fungus. Only the spray of RsCRZ1 dsRNA, but not RsPG1 or RsCATA dsRNA, affected fungal sclerotium formation. dsRNA stability on leaf surfaces and its efficiency in entering leaf cells were significantly improved when dsRNAs were loaded on layered double hydroxide (LDH) nanosheets. Notably, the RsCRZ1-dsRNA-LDH approach showed stronger and more lasting effects than using RsCRZ1-dsRNA alone in controlling pathogen development. Together, this study provides a new potential method to control crop diseases caused by R. solani.
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Lu S, Zhang H, Guo F, Yang Y, Shen X, Chen B. SsUbc2, a determinant of pathogenicity, functions as a key coordinator controlling global transcriptomic reprogramming during mating in sugarcane smut fungus. Front Microbiol 2022; 13:954767. [PMID: 36204604 PMCID: PMC9530204 DOI: 10.3389/fmicb.2022.954767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
The basidiomycete fungus Sporisorium scitamineum is the causative agent of sugarcane smut disease. Mating between two strains of the opposite mating type is essential for filamentous growth and infection in sugarcane plants. However, the mechanisms underlying mating and pathogenicity are still not well understood. In this work we used gene disruption to investigate the role of Ssubc2, the gene encoding a kinase regulator in S. scitamineum. Deletion of Ssubc2 did not alter the haploid cell morphology or growth rate in vitro or tolerance to stress, but mutants with both alleles deleted lost mating ability and infectivity. Deletion of one Ssubc2 allele in a pair with a wild-type strain resulted in impaired mating and reduced virulence. Transcriptome profiling revealed that about a third of genes underwent reprogramming in the wild types during mating. Although gene expression reprogramming occurred in the pairing of Ssubc2-null mutants, their transcriptomic profile differed significantly from that of the wild types, in which 625 genes differed from those present in the wild types that seemed to be among the required genes for a successful mating. These genes include those known to regulate mating and pathogenicity, such as components of the MAPK pathway and hgl1. Additionally, a total of 908 genes were differentially expressed in an out-of-control manner in the mutants. We conclude that SsUbc2 functions as a key factor to coordinate the reprogramming of gene expression at the global level and is essential for the transition from monokaryotic basidial growth to dikaryotic hyphal growth through mating.
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Affiliation(s)
- Shan Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Ministry and Province Co-sponsored Collaborative Innovation Center for Sugarcane and Sugar Industry, Nanning, China
- Guangxi Key Laboratory of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning, China
| | - Haoyang Zhang
- Guangxi Key Laboratory of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning, China
| | - Feng Guo
- College of Life Science and Technology, Guangxi University, Nanning, China
| | - Yanfang Yang
- Guangxi Key Laboratory of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning, China
| | - Xiaorui Shen
- College of Life Science and Technology, Guangxi University, Nanning, China
| | - Baoshan Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Ministry and Province Co-sponsored Collaborative Innovation Center for Sugarcane and Sugar Industry, Nanning, China
- Guangxi Key Laboratory of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning, China
- *Correspondence: Baoshan Chen,
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Ray P, Sahu D, Aminedi R, Chandran D. Concepts and considerations for enhancing RNAi efficiency in phytopathogenic fungi for RNAi-based crop protection using nanocarrier-mediated dsRNA delivery systems. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:977502. [PMID: 37746174 PMCID: PMC10512274 DOI: 10.3389/ffunb.2022.977502] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/19/2022] [Indexed: 09/26/2023]
Abstract
Existing, emerging, and reemerging strains of phytopathogenic fungi pose a significant threat to agricultural productivity globally. This risk is further exacerbated by the lack of resistance source(s) in plants or a breakdown of resistance by pathogens through co-evolution. In recent years, attenuation of essential pathogen gene(s) via double-stranded (ds) RNA-mediated RNA interference (RNAi) in host plants, a phenomenon known as host-induced gene silencing, has gained significant attention as a way to combat pathogen attack. Yet, due to biosafety concerns regarding transgenics, country-specific GMO legislation has limited the practical application of desirable attributes in plants. The topical application of dsRNA/siRNA targeting essential fungal gene(s) through spray-induced gene silencing (SIGS) on host plants has opened up a transgene-free avenue for crop protection. However, several factors influence the outcome of RNAi, including but not limited to RNAi mechanism in plant/fungi, dsRNA/siRNA uptake efficiency, dsRNA/siRNA design parameters, dsRNA stability and delivery strategy, off-target effects, etc. This review emphasizes the significance of these factors and suggests appropriate measures to consider while designing in silico and in vitro experiments for successful RNAi in open-field conditions. We also highlight prospective nanoparticles as smart delivery vehicles for deploying RNAi molecules in plant systems for long-term crop protection and ecosystem compatibility. Lastly, we provide specific directions for future investigations that focus on blending nanotechnology and RNAi-based fungal control for practical applications.
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Affiliation(s)
- Poonam Ray
- Laboratory of Plant-Microbe Interactions, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India
| | - Debashish Sahu
- Laboratory of Plant-Microbe Interactions, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India
| | - Raghavendra Aminedi
- Division of Genomic Resources, ICAR-National Bureau of Plant Genetic Resources, New Delhi, India
| | - Divya Chandran
- Laboratory of Plant-Microbe Interactions, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India
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Wang M, Dean RA. Host induced gene silencing of Magnaporthe oryzae by targeting pathogenicity and development genes to control rice blast disease. FRONTIERS IN PLANT SCIENCE 2022; 13:959641. [PMID: 36035704 PMCID: PMC9403838 DOI: 10.3389/fpls.2022.959641] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Rice blast disease caused by the hemi-biotrophic fungus Magnaporthe oryzae is the most destructive disease of rice world-wide. Traditional disease resistance strategies for the control of rice blast disease have not proved durable. HIGS (host induced gene silencing) is being developed as an alternative strategy. Six genes (CRZ1, PMC1, MAGB, LHS1, CYP51A, CYP51B) that play important roles in pathogenicity and development of M. oryzae were chosen for HIGS. HIGS vectors were transformed into rice calli through Agrobacterium-mediated transformation and T0, T1 and T2 generations of transgenic rice plants were generated. Except for PMC1 and LHS1, HIGS transgenic rice plants challenged with M. oryzae showed significantly reduced disease compared with non-silenced control plants. Following infection with M. oryzae of HIGS transgenic plants, expression levels of target genes were reduced as demonstrated by Quantitative RT-PCR. In addition, treating M. oryzae with small RNA derived from the target genes inhibited fungal growth. These findings suggest RNA silencing signals can be transferred from host to an invasive fungus and that HIGS has potential to generate resistant rice against M. oryzae.
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