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Yang H, Yu H, Wang S, Bayouli IT, Huang H, Ye D, Zhang X, Liu T, Wang Y, Zheng Z, Meers E, Li T. Root radial apoplastic transport contributes to shoot cadmium accumulation in a high cadmium-accumulating rice line. JOURNAL OF HAZARDOUS MATERIALS 2023; 460:132276. [PMID: 37625294 DOI: 10.1016/j.jhazmat.2023.132276] [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: 05/24/2023] [Revised: 08/01/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023]
Abstract
Radial transport of cadmium (Cd) in roots governs the amount of Cd loaded into xylem vessels, where Cd ions are translocated upward into shoots, while the mechanism of differential Cd radial transport between the high Cd-accumulating rice line Lu527-8 and the normal rice line Lu527-4 remains ambiguous. A higher Cd distribution in cross sections and root apoplast and higher bypass flow of Cd were found in Lu527-8, explaining a greater Cd translocation through the apoplastic pathway. The lower relative area of the epidermis and the constant relative area of the cortex in Lu527-8 opened-up root radial transport for Cd. Deposition of apoplastic barriers (Casparian strips and suberin lamellae) was stimulated by Cd, which effectively prevented Cd from entering the stele through the apoplastic pathway. In Lu527-8, apoplastic barriers were further from the root apex with lower expression of genes responsible for biosynthesis of Casparian strips and suberin lamellae, enhancing radial transport of Cd. Our data revealed that the higher radial apoplastic transport of Cd played an integral role in Cd translocation, contributed to a better understanding of the mechanism involved in high Cd accumulation in Lu527-8 and helped achieve the practical application of phytoextraction.
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Affiliation(s)
- Huan Yang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; Lab for bioresource recovery, Faculty of Bioscience Engineering, Ghent University, Ghent 9000, Belgium
| | - Haiying Yu
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Shengwang Wang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Ines Terwayet Bayouli
- Lab for bioresource recovery, Faculty of Bioscience Engineering, Ghent University, Ghent 9000, Belgium
| | - Huagang Huang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Daihua Ye
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Xizhou Zhang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Tao Liu
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Yongdong Wang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Zicheng Zheng
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China
| | - Erik Meers
- Lab for bioresource recovery, Faculty of Bioscience Engineering, Ghent University, Ghent 9000, Belgium
| | - Tingxuan Li
- College of Resources, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
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Hu X, Wang J, Zhang Y, Wu X, Li R, Li M. Visualization of the entire process of rice spikelet infection by Ustilaginoidea virens through nondestructive inoculation. Front Microbiol 2023; 14:1228597. [PMID: 37637108 PMCID: PMC10450503 DOI: 10.3389/fmicb.2023.1228597] [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: 05/25/2023] [Accepted: 07/25/2023] [Indexed: 08/29/2023] Open
Abstract
Introduction Rice false smut caused by Ustilaginoidea virens, is a destructive fungal disease encountered in many rice-producing areas worldwide. To determine the process by which U. virens infects rice spikelets in the field. Methods The green fluorescent protein-labeled U. virens was used as an inoculum to conduct artificial inoculation on rice at the booting stage via non-destructive panicle sheath instillation inoculation. Results The results showed that the conidia of U. virens germinated on the surface of rice glumes and produced hyphae, which clustered at the mouth of rice glumes and entered the glumes through the gap between the palea and lemma. The conidia of U. virens colonized in rice floral organs, which led to pollen abortion of rice. U. virens wrapped the whole rice floral organ, and the floral organ-hyphae complex gradually expanded to open the glumes to form a rice false smut ball, which was two to three times larger than that observed in normal rice. Discussion Panicle sheath instillation inoculation was shown to be a non-destructive inoculation method that could simulate the natural infection of U. virens in the field. The entire infection process of U. virens was visualized, providing a theoretical reference for formulating strategies to control rice false smut in the field.
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Affiliation(s)
- Xianfeng Hu
- College of Agriculture, Anshun University, Anshun, Guizhou, China
| | - Jian Wang
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou, China
- College of Agriculture, Guizhou University, Guiyang, Guizhou, China
| | - Yubo Zhang
- College of Agriculture, Anshun University, Anshun, Guizhou, China
| | - Xiaomao Wu
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou, China
- College of Agriculture, Guizhou University, Guiyang, Guizhou, China
- Provincial Key Laboratory for Agricultural Pest Management in Mountainous Region, Guizhou University, Guiyang, Guizhou, China
| | - Rongyu Li
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou, China
- College of Agriculture, Guizhou University, Guiyang, Guizhou, China
- Provincial Key Laboratory for Agricultural Pest Management in Mountainous Region, Guizhou University, Guiyang, Guizhou, China
| | - Ming Li
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou, China
- College of Agriculture, Guizhou University, Guiyang, Guizhou, China
- Provincial Key Laboratory for Agricultural Pest Management in Mountainous Region, Guizhou University, Guiyang, Guizhou, China
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3
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Shen E, Wang X, Lu Z, Zhou F, Ma W, Cui Z, Li Z, Li C, Lin Y. Overexpression of a beta-1,6-glucanase gene GluM in transgenic rice confers high resistance to rice blast, sheath blight and false smut. PEST MANAGEMENT SCIENCE 2023; 79:2152-2162. [PMID: 36729081 DOI: 10.1002/ps.7394] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 01/20/2023] [Accepted: 02/02/2023] [Indexed: 05/03/2023]
Abstract
BACKGROUND Frequent fungal diseases tend to lead to severe losses in rice production. As a main component of the fungal cell wall, glucan plays an important role in the growth and development of fungi. Glucanase can inhibit the growth of fungi by breaking glycosidic bonds, and may be a promising target for developing rice varieties with broad-spectrum disease resistance. RESULTS We transferred a codon-optimized β-1,6-glucanase gene (GluM) from myxobacteria into the japonica rice variety Zhonghua11 (ZH11), and obtained a large number of individual transgenic plants with GluM overexpression. Based on molecular analysis, three single-copy homozygous lines with GluM overexpression were selected for assessment of fungal disease resistance at the T3 generation. Compared with that of the recipient cultivar ZH11, the area of rice blast lesion in transgenic rice was reduced by 82.71%; that of sheath blight lesion was decreased by 35.76%-43.67%; the sheath blight resistance in the field was enhanced by an average of 0.75 grade over 3 years; and the incidence of diseased panicles due to rice false smut was decreased by 65.79%. More importantly, there was no obvious loss of yield (without a significant effect on agronomic traits). Furthermore, plants overexpressing a β-1,6-glucanase gene showed higher disease resistance than rice plants overexpressing a β-1,3-glucanase gene derived from tobacco. CONCLUSION The β-1,6-glucanase gene GluM can confer broad-spectrum disease resistance to rice, providing an environmentally friendly alternative way to effectively manage fungal pathogens in rice production. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Enlong Shen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xingchao Wang
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhaoxi Lu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Fei Zhou
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhongli Cui
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Biological Interaction and Crop Health, Nanjing Agricultural University, Nanjing, China
| | - Zhoukun Li
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Changyan Li
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
- Hubei Key Laboratory of Food Crop Germplasm and Genetic Improvement, Food Crops Institute, Hubei Academy of Agricultural Sciences, Wuhan, China
| | - Yongjun Lin
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
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Fu X, Jin Y, Paul MJ, Yuan M, Liang X, Cui R, Huang Y, Peng W, Liang X. Inhibition of rice germination by ustiloxin A involves alteration in carbon metabolism and amino acid utilization. FRONTIERS IN PLANT SCIENCE 2023; 14:1168985. [PMID: 37223794 PMCID: PMC10200953 DOI: 10.3389/fpls.2023.1168985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 04/11/2023] [Indexed: 05/25/2023]
Abstract
Ustiloxins are the main mycotoxin in rice false smut, a devastating disease caused by Ustilaginoidea virens. A typical phytotoxicity of ustiloxins is strong inhibition of seed germination, but the physiological mechanism is not clear. Here, we show that the inhibition of rice germination by ustiloxin A (UA) is dose-dependent. The sugar availability in UA-treated embryo was lower while the starch residue in endosperm was higher. The transcripts and metabolites responsive to typical UA treatment were investigated. The expression of several SWEET genes responsible for sugar transport in embryo was down-regulated by UA. Glycolysis and pentose phosphate processes in embryo were transcriptionally repressed. Most of the amino acids detected in endosperm and embryo were variously decreased. Ribosomal RNAs for growth were inhibited while the secondary metabolite salicylic acid was also decreased under UA. Hence, we propose that the inhibition of seed germination by UA involves the block of sugar transport from endosperm to embryo, leading to altered carbon metabolism and amino acid utilization in rice plants. Our analysis provides a framework for understanding of the molecular mechanisms of ustiloxins on rice growth and in pathogen infection.
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Affiliation(s)
- Xiaoxiang Fu
- The Laboratory for Phytochemistry and Botanical Pesticides, College of Agriculture, Jiangxi Agricultural University, Nanchang, China
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education/Jiangxi Province, Jiangxi Agricultural University, Nanchang, China
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Yu Jin
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education/Jiangxi Province, Jiangxi Agricultural University, Nanchang, China
| | - Matthew J. Paul
- Plant Sciences, Rothamsted Research, Harpenden, United Kingdom
| | - Minxuan Yuan
- The Laboratory for Phytochemistry and Botanical Pesticides, College of Agriculture, Jiangxi Agricultural University, Nanchang, China
| | - Xingwei Liang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education/Jiangxi Province, Jiangxi Agricultural University, Nanchang, China
| | - Ruqiang Cui
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education/Jiangxi Province, Jiangxi Agricultural University, Nanchang, China
| | - Yingjin Huang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education/Jiangxi Province, Jiangxi Agricultural University, Nanchang, China
| | - Wenwen Peng
- The Laboratory for Phytochemistry and Botanical Pesticides, College of Agriculture, Jiangxi Agricultural University, Nanchang, China
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education/Jiangxi Province, Jiangxi Agricultural University, Nanchang, China
| | - Xiaogui Liang
- The Laboratory for Phytochemistry and Botanical Pesticides, College of Agriculture, Jiangxi Agricultural University, Nanchang, China
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education/Jiangxi Province, Jiangxi Agricultural University, Nanchang, China
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
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Jose RC, Kanchal T, Louis B, Talukdar NC, Chowdhury D. Grain Characteristics, Moisture, and Specific Peptides Produced by Ustilaginoidea virens Contribute to False Smut Disease in Rice ( Oryza sativa L.). Biomolecules 2023; 13:biom13040669. [PMID: 37189416 DOI: 10.3390/biom13040669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/20/2023] [Accepted: 02/23/2023] [Indexed: 05/17/2023] Open
Abstract
The fungus Ustilaginoidea virens, the causative agent of false smut in rice (Oryza sativa L.), is responsible for one of the severe grain diseases that lead to significant losses worldwide. In this research, microscopic and proteomic analyses were performed by comparing U. virens infected and non-infected grains of the susceptible and resistant rice varieties to provide insights into the molecular and ultrastructural factors involved in false smut formation. Prominent differentially expressed peptide bands and spots were detected due to false smut formation as revealed by sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimensional gel electrophoresis (2-DE) SDS-PAGE profiles and were identified using liquid chromatography-mass spectrometry (LC-MS/MS). The proteins identified from the resistant grains were involved in diverse biological processes such as cell redox homeostasis, energy, stress tolerance, enzymatic activities, and metabolic pathways. It was found that U. virens produces diverse degrading enzymes such as β-1, 3-endoglucanase, subtilisin-like protease, putative nuclease S1, transaldolase, putative palmitoyl-protein thioesterase, adenosine kinase, and DNase 1 that could discretely alter the host morphophysiology resulting in false smut. The fungus also produced superoxide dismutase, small secreted proteins, and peroxidases during the smut formation. This study revealed that the dimension of rice grain spikes, their elemental composition, moisture content, and the specific peptides produced by the grains and the fungi U. virens play a vital role in the formation of false smut.
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Affiliation(s)
- Robinson C Jose
- Institute of Advanced Study in Science and Technology, Guwahati 781035, India
- Institute of Bioresources and Sustainable Development (IBSD), Imphal 795001, India
| | - Thangjam Kanchal
- Institute of Bioresources and Sustainable Development (IBSD), Imphal 795001, India
| | - Bengyella Louis
- Department of Plant Sciences, University Park, Pennsylvania State University, 101 Tyson Bldg, State College, PA 16802, USA
| | - Narayan C Talukdar
- Institute of Advanced Study in Science and Technology, Guwahati 781035, India
- Faculty of Science, Assam Down Town University, Guwahati 781026, India
| | - Devasish Chowdhury
- Institute of Advanced Study in Science and Technology, Guwahati 781035, India
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Hu X, Wang J, Li R, Wu X, Gao X, Li M. Establishment of an Artificial Inoculation Method of Ustilaginoidea virens Without Damaging the Rice Panicle Sheaths. PLANT DISEASE 2022; 106:289-296. [PMID: 34515502 DOI: 10.1094/pdis-12-20-2746-re] [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: 06/13/2023]
Abstract
Rice false smut (RFS) is a destructive disease of rice worldwide caused by Ustilaginoidea virens. Nevertheless, there is a lack of efficient and stable artificial inoculation method to simulate the natural infection of U. virens, which is an important factor limiting further research on the pathogen. The purpose of this study was to establish an artificial inoculation method, which can simulate the natural infection process of U. virens without destroying the panicle sheath structure of rice. In this research, rice plants were inoculated by soaking roots at the seedling stage, spraying at the tillering stage, injecting at the booting stage, and again spraying at the flowering stage to determine the appropriate artificial inoculation time. Meanwhile, the panicle sheath instillation method and the injection inoculation method were compared. The results show that stages 6 to 8 of young panicle differentiation are an important period for U. virens infection. There were no significant differences in the mean rates of infected panicles, mean rates of infected grains, and maximum infected grains per panicle between the two inoculation methods. However, the frequency of RFS ball occurrence at the upper part of the panicles was significantly higher on the spikelets inoculated by the injection method than that of spikelets inoculated by natural infection and panicle sheath instillation. Therefore, panicle sheath instillation method was more similar to the natural infection of U. virens in the field. This research exhibited an innovative artificial inoculation method for identification of U. virens pathogenicity and evaluation of rice resistance against RFS.
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Affiliation(s)
- Xianfeng Hu
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- College of Agriculture, Guizhou University, Guiyang, Guizhou 550025, P. R. China
| | - Jian Wang
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- College of Agriculture, Guizhou University, Guiyang, Guizhou 550025, P. R. China
| | - Rongyu Li
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- College of Agriculture, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- The Provincial Key Laboratory for Agricultural Pest Management in Mountainous Region, Guizhou University, Guiyang, Guizhou 550025, P. R. China
| | - Xiaomao Wu
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- College of Agriculture, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- The Provincial Key Laboratory for Agricultural Pest Management in Mountainous Region, Guizhou University, Guiyang, Guizhou 550025, P. R. China
| | - Xiubing Gao
- Institute of Crop Protection, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- College of Agriculture, Guizhou University, Guiyang, Guizhou 550025, P. R. China
| | - Ming Li
- College of Agriculture, Guizhou University, Guiyang, Guizhou 550025, P. R. China
- The Provincial Key Laboratory for Agricultural Pest Management in Mountainous Region, Guizhou University, Guiyang, Guizhou 550025, P. R. China
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7
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Song JH, Wang YF, Yin WX, Huang JB, Luo CX. Effect of Chemical Seed Treatment on Rice False Smut Control in Field. PLANT DISEASE 2021; 105:3218-3223. [PMID: 33529066 DOI: 10.1094/pdis-11-19-2411-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Rice false smut, caused by the pathogen Ustilaginoidea virens, is a severe emerging disease in China. It affects not only the quality of rice but also yields of rice production. To make clear the effect of chemical seed treatment on the rice false smut control in fields, during 2014 to 2017, four fungicides with different modes of action were used to treat rice seeds contaminated by false smut balls. In rice-growing seasons, samples of rice tissues were taken for detection of U. virens by using a specific nested PCR method at different rice-growing stages. In addition, the occurrence of rice false smut was investigated at maturation stage. Results showed that U. virens in plant tissues decreased significantly at the seedling stage upon chemical seed treatment. Four chemical treatments decreased the detection rate significantly (P < 0.01) compared with the water treatment, but no significant difference was observed among four chemical treatments. However, the detection rate did not decease significantly at the tillering and booting stages. Similarly, the final occurrence of rice false smut did not show significant difference between each chemical and water treatment. These results suggested that chemical seed treatment had only limited efficacy in preventing occurrence of rice false smut; application of fungicides at the booting stage or integrated use of fungicides and agricultural practices might give a better control for this disease.
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Affiliation(s)
- Jie-Hui Song
- Jiangsu Key Laboratory of Crop Genetics and Physiology and Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
- College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan 430070, China
| | - Yu-Fu Wang
- College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan 430070, China
| | - Wei-Xiao Yin
- College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan 430070, China
| | - Jun-Bin Huang
- College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan 430070, China
| | - Chao-Xi Luo
- College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan 430070, China
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8
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Sun W, Fan J, Fang A, Li Y, Tariqjaveed M, Li D, Hu D, Wang WM. Ustilaginoidea virens: Insights into an Emerging Rice Pathogen. ANNUAL REVIEW OF PHYTOPATHOLOGY 2020; 58:363-385. [PMID: 32364825 DOI: 10.1146/annurev-phyto-010820-012908] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
False smut of rice, caused by Ustilaginoidea virens, has become one of the most important diseases in rice-growing regions worldwide. The disease causes a significant yield loss and imposes health threats to humans and animals by producing mycotoxins. In this review, we update our understanding of the pathogen, including the disease cycle and infection strategies, the decoding of the U. virens genome, comparative/functional genomics, and effector biology. Whereas the decoding of the U. virens genome unveils specific adaptations of the pathogen in successfully occupying rice flowers, progresses in comparative/functional genomics and effector biology have begun to uncover the molecular mechanisms underlying U. virens virulence and pathogenicity. We highlight the identification and characterization of the produced mycotoxins and their biosynthetic pathways in U. virens.The management strategies for this disease are also discussed. The flower-specific infection strategy makes the pathogen a unique tool to unveil novel mechanisms for the interactions between nonobligate biotrophic pathogens and their hosts.
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Affiliation(s)
- Wenxian Sun
- College of Plant Protection, Jilin Agricultural University, Changchun 130118, China;
- College of Plant Protection and the Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, China Agricultural University, Beijing 100193, China
| | - Jing Fan
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China;
| | - Anfei Fang
- College of Plant Protection, Southwest University, Chongqing 400715, China
| | - Yuejiao Li
- College of Plant Protection and the Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, China Agricultural University, Beijing 100193, China
| | - Muhammad Tariqjaveed
- College of Plant Protection and the Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, China Agricultural University, Beijing 100193, China
| | - Dayong Li
- College of Plant Protection, Jilin Agricultural University, Changchun 130118, China;
| | - Dongwei Hu
- State Key Laboratory of Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou 310058, China
| | - Wen-Ming Wang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China;
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9
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Yu J, Yu M, Song T, Cao H, Pan X, Yong M, Qi Z, Du Y, Zhang R, Yin X, Liu Y. A Homeobox Transcription Factor UvHOX2 Regulates Chlamydospore Formation, Conidiogenesis, and Pathogenicity in Ustilaginoidea virens. Front Microbiol 2019; 10:1071. [PMID: 31281290 PMCID: PMC6596325 DOI: 10.3389/fmicb.2019.01071] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 04/29/2019] [Indexed: 12/21/2022] Open
Abstract
Rice false smut fungus (teleomorph: Villosiclava virens; anamorph: Ustilaginoidea virens) can generate chlamydospores and survive winter under field conditions. The chlamydospore is considered as an important infection source of the disease. However, little is known about the regulatory mechanism of the chlamydospore production. In this study, we identified a defective homeobox transcription factor (designated as UvHOX2) gene in a U. virens random insertional mutant B-766 that could not form chlamydospores. To confirm the regulatory function of UvHOX2, an Agrobacterium tumefaciens mediated transformation- and CRISPR/Cas9- based targeted gene replacement method was developed. The UvHox2 deletion mutants completely failed to produce chlamydospores, showed reduced conidia production and decreased virulence, and was hyper-sensitive to oxidative, osmotic, and cell wall stresses. We confirmed that UvHOX2 is located in the nuclei of U. virens, and the expression of UvHox2 was the strongest during the early stage of chlamydospore and conidium formation. Global transcription pattern of UvHOX2 was also determined by RNA-seq in this study, and several genes that might be down-stream of UvHOX2 regulation were identified. The results will better our understanding of the molecular mechanism of chlamydospore formation in U. virens as a model fungus.
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Affiliation(s)
- Junjie Yu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Mina Yu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Tianqiao Song
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Huijuan Cao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Xiayan Pan
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Mingli Yong
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Zhongqiang Qi
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yan Du
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Rongsheng Zhang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Xiaole Yin
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yongfeng Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,School of the Environment and Safety Engineering, Jiangsu University, Zhengjiang, China
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10
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Fang A, Gao H, Zhang N, Zheng X, Qiu S, Li Y, Zhou S, Cui F, Sun W. A Novel Effector Gene SCRE2 Contributes to Full Virulence of Ustilaginoidea virens to Rice. Front Microbiol 2019; 10:845. [PMID: 31105658 PMCID: PMC6492501 DOI: 10.3389/fmicb.2019.00845] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 04/02/2019] [Indexed: 12/13/2022] Open
Abstract
Ustilaginoidea virens, the causal agent of rice false smut (RFS), has become one of the most devastating rice pathogens worldwide. As a group of essential virulence factors, the effectors in the filamentous fungus might play central roles in the interaction between plants and pathogens. However, little is known about the roles of individual effectors in U. virens virulence. In this study, we identified and characterized a small secreted cysteine-rich effector, SCRE2, in U. virens. SCRE2 was first confirmed as an effector through yeast secretion, protein localization and translocation assays, as well as its expression pattern during U. virens infection. Transient expression of SCRE2 in Nicotiana benthamiana suppressed necrosis-like defense symptoms triggered by the mammalian BAX and oomycete elicitin INF1 proteins. The ability of SCRE2 to inhibit immunity-associated responses in N. benthamiana, including elicitor-triggered cell death and oxidative burst, is further defined to a small peptide region SCRE268-85 through expressing a series of truncated proteins. Convincingly, ectopic expression of SCRE2 in the transgenic rice cells significantly inhibited pathogen-associated molecular pattern-triggered immunity including flg22- and chitin-induced defense gene expression and oxidative burst. Furthermore, the scre2 knockout mutant generated by the CRISPR/Cas9 system greatly attenuated in U. virens virulence to rice. Collectively, this study indicates that the effector SCRE2 is able to inhibit plant immunity and is required for full virulence of U. virens.
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Affiliation(s)
- Anfei Fang
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China.,College of Plant Protection, Southwest University, Chongqing, China
| | - Han Gao
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China
| | - Nan Zhang
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China
| | - Xinhang Zheng
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China
| | - Shanshan Qiu
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China
| | - Yuejiao Li
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China
| | - Shuang Zhou
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China
| | - Fuhao Cui
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China
| | - Wenxian Sun
- The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Plant Protection, China Agricultural University, Beijing, China.,College of Plant Protection, Jilin Agricultural University, Changchun, China
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