Several viroids in the genus Pospiviroid can infect tomato(Solanum lycopersicum)and cause severe diseases,posing a serious threat to tomato production.For simultaneous detection of six tomato-infecting pospiviroids-co...Several viroids in the genus Pospiviroid can infect tomato(Solanum lycopersicum)and cause severe diseases,posing a serious threat to tomato production.For simultaneous detection of six tomato-infecting pospiviroids-columnea latent viroid(CLVd),pepper chat fruit viroid(PCFVd),potato spindle tuber viroid(PSTVd),tomato apical stunt viroid(TASVd),tomato chlorotic dwarf viroid(TCDVd),and tomato planta macho viroid(TPMVd),we developed a universal probe based on a highly conserved 61 nt long sequence shared among them.Compared with their specific probes,the universal probe has a similar,though slightly reduced,detection sensitivity and has the advantages of simple and cost-effective preparation and simultaneous detection of the six pospiviroids.In addition,the universal probe was used in dot-blot hybridization assays for a large-scale survey of viroid(s)in tomato plantings in China.Only PSTVd was detected in a few greenhouse-planted tomato plants.Sequence analysis revealed that these tomato PSTVd isolates may have been introduced from tomato seeds imported from abroad.展开更多
Citrus viroids are the small but economically important RNA pathogens. For investigating their occurrence and distribution in China, 65 viroid samples collected from 8 major citrus cultivated regions were evaluated us...Citrus viroids are the small but economically important RNA pathogens. For investigating their occurrence and distribution in China, 65 viroid samples collected from 8 major citrus cultivated regions were evaluated using one-step or multiplex onestep RT-PCR and biological indexing for specifically detection of Citrus exocortis viroid （CEVd）, Citrus bent leaf viroid （CBLVd）, Hop stunt viroid （HSVd）, Citrus viroid-Ⅲ （CVd-Ⅲ） and Citrus viroid-Ⅳ （CVd-Ⅳ）. The results showed that there were at least 4 kinds of citrus viroids （CEVd, CBLVd, HSVd, and CVd-Ⅲ） on citrus trees in China. Most of the infected citrus plants harbored more than one viroid species, and two plants were infected with up to 4 citrus viroids. Sweet orange was more frequently infected by viroids than other citrus varieties. It is the preliminary report on the species and distribution of citrus viroids in China.展开更多
China is the largest potato producing country worldwide,with this crop representing the fourth largest staple food crop in China.However,the steady presence of Potato spindle tuber viroid（PSTVd） over the past five d...China is the largest potato producing country worldwide,with this crop representing the fourth largest staple food crop in China.However,the steady presence of Potato spindle tuber viroid（PSTVd） over the past five decades has a significant economic impact on potato production.To determine why PSTVd control measures have been ineffective in China,more than 1 000 seed potatoes collected between 2009 and 2014 were subjected to PSTVd detection at the Supervision and Testing Center for Virus-free Seed Potatoes Quality,Ministry of Agriculture,China.A high PSTVd infection rate（6.5%） was detected among these commercial seed potatoes.Some breeding lines of potato collected from 2012 to 2015 were also tested for PSTVd infection,revealing a high rate of PSTVd contamination in these potato propagation materials.Furthermore,comparison of the full-length sequences of 71 different Chinese PSTVd isolates revealed a total of 74 predominant PSTVd variants,which represented 42 different sequence variants of PSTVd.Comparative sequence analysis revealed 30 novel PSTVd sequence variants specific to China.Comprehensive phylogenetic analysis uncovered a close relationship between the Chinese PSTVd sequence variants and those isolated from Russia.It is worth noting that three intermediate strains and six mild strains were identified among these variants.These results have important implications for explaining the ineffective control of PSTVd in China and thus could serve as a basic reference for designing more effective measures to eliminate PSTVd from China in the future.展开更多
Total RNA was isolated from the phloem of young shoots and retro-transcripted to cDNA by reverse transcriptasepolymerase chain reaction （RT-PCR） with specific primers; the amplified cDNA fragments were sequenced for...Total RNA was isolated from the phloem of young shoots and retro-transcripted to cDNA by reverse transcriptasepolymerase chain reaction （RT-PCR） with specific primers; the amplified cDNA fragments were sequenced for identification of subtypes. In this study, an effective RT-PCR technique was established for detecting citrus viroids, and three citrus viroids were recognized, namely, CEVd, CVd-II, and CVd-III. The latter two were identified for the first time in China. The sequences of CVd-Ⅱ were different from all the three subtypes reported in the GenBank and seemed to be a new subtype. CVd-Ⅲb detected in the present study could be further developed as a dwarfing agent.展开更多
Potato spindle tuber viroid(PSTVd)disease is one of the major diseases that threatens potato production.Therefore,an advanced,rapid and sensitive detection technology is needed to detect the disease for better control...Potato spindle tuber viroid(PSTVd)disease is one of the major diseases that threatens potato production.Therefore,an advanced,rapid and sensitive detection technology is needed to detect the disease for better control.In order to establish an easier nucleic acid spot hybridization(NASH)method,some studies were tried as the followings:(1)the pre-hybridization step of nucleic acid spot hybridization(NASH)was omitted compared with ordinary way;(2)RNA extraction(phenol extraction and Ames buffer extraction)methods were compared;(3)fixed RNA by UV lamp and oven compared with UV cross-linker;(4)hybridized the RNA in shaking incubator and so on.The results showed that RNA extracted by Ames buffer was more effective than by the phenol extraction method.Besides,the result of hybridization without pre-hybridization step was better than that with 1.5 h of pre-hybridization.The more important discovery was that the shaking incubator could replace the hybridization oven and the ordinary UV lamp could replace the UV cross-linker.After a long term repeated research and testing,a new hybridization system that could rapidly detect the PSTVd by improved NASH technique merely using common instruments and equipment was established.展开更多
The viability of most tomato varieties cultivated in Libya have been tested to infect with potato spindle tuber viroid/potatoes （PSTVd） and its impact on growth and production of some of these varieties, which were ...The viability of most tomato varieties cultivated in Libya have been tested to infect with potato spindle tuber viroid/potatoes （PSTVd） and its impact on growth and production of some of these varieties, which were mechanically inoculated with Libyan isolate of viroid PSTVd as follows： Vlkato, Sankarh, Lebda, Jasmine, Kenza and Hana. The percent of incidence were 95.95%, 90%, 90.80%, 80% and 20%, respectively. The following varieties have been contagious mechanically with viroid of PSTVd： Vlkato, zahra, Toria, Lebda, Hoda, Farwa, Alkaraz, Naziha, Rim Star and Kartika. The percent of incidence were 95.95%, 85%, 85.80%, 80%, 70.40%, 0.0%, 0.0%, respectively. The varied symptoms of wrinkle, twist, warp, swell the veins of the leaves, dark brown spots formation and a large yellow spots turned into white patches. Also the effect of the Egyptian isolate viroid PSTVd in the growth and production of varieties Jasmine, Lebda, Soberhalim, and treasure No. 185 had been studied, as the average rates of decline in the production of the fruits tomatoes/tomato 43.4% and 17% length of plants, and in the fresh weight and dry root of the sum of 35% and 37% respictively.展开更多
Citrus viroids are small non-coding RNA pathogens that pose a significant threat to global citrus production by reducing fruit yield,quality,and tree longevity.Several viroids,including Citrus exocortis viroid(CEVd),H...Citrus viroids are small non-coding RNA pathogens that pose a significant threat to global citrus production by reducing fruit yield,quality,and tree longevity.Several viroids,including Citrus exocortis viroid(CEVd),Hop stunt viroid(HSVd),Citrus bent leaf viroid(CBLVd),and newly identified members such as Citrus Viroid VI(CVd-VI)and Citrus Viroid VII(CVd-VII)have been reported from diverse citrus-growing regions.These pathogens are transmitted mainly through vegetative propagation,contaminated tools,and occasionally via seed or pollen,making their management complex.This review synthesizes current knowledge on the biology,structural diversity,transmission,symptomatology,detection,and economic impact of citrus viroids.In addition to compiling existing findings,it emphasizes critical challenges such as understanding host–pathogen molecular interactions,the implications of viroid infections under climate change,and the limited availability of resistant rootstocks.Recent advances in diagnostic tools,including Reverse Transcription Polymerase Chain Reaction(RT-PCR),Quantitative Polymerase Chain Reaction(qPCR),High-throughput sequencing(HTS),and in silico approaches,are evaluated alongside practical constraints in low-resource settings.Furthermore,the review highlights management strategies focused on certified planting material,sanitation,resistant genotypes,and integration into global citrus certification programs.By consolidating existing information while outlining key knowledge gaps and future directions,this work provides a foundation for developing sustainable strategies to mitigate the impact of viroids on the citrus industry.展开更多
Wu M,Li W,Hu N,Liu C,Li J,Li Y,et al.Discovery of a Novel Viroid-Like Circular RNA in Colorectal Cancer.Cancer Commun.2025;45(1):46-50.doi:10.1002/cac2.12626.This Expression of Concern is for the above article,publish...Wu M,Li W,Hu N,Liu C,Li J,Li Y,et al.Discovery of a Novel Viroid-Like Circular RNA in Colorectal Cancer.Cancer Commun.2025;45(1):46-50.doi:10.1002/cac2.12626.This Expression of Concern is for the above article,published online on 09November 2024 in WileyOnline Library(wileyonlinelibrary.com),and has been issued by agreement between the journal Editor-in-Chief,Rui-Hua Xu;Sun Yat-sen University Cancer Center;and JohnWiley&Sons Australia.The Expression of Concern has been agreed upon following information provided by a third party regarding the identification of the CRC-associated viroid.The authors reported this viroid-like circRNA as absent from the human genome based on the hg38 reference.However,the sequence is present at chromosome13:96543662-96543775 in the more complete T2T human genome reference,indicating it is not an exogenous RNA element.The authors have acknowledged the need for further investigation,particularly in light of the discrepancies from the difference between the hg38 and T2T human genomes.The editors have decided to issue this Expression of Concern to alert readers as further investigations proceed.展开更多
基金funded by the National Natural Science Foundation of China(31670149)。
文摘Several viroids in the genus Pospiviroid can infect tomato(Solanum lycopersicum)and cause severe diseases,posing a serious threat to tomato production.For simultaneous detection of six tomato-infecting pospiviroids-columnea latent viroid(CLVd),pepper chat fruit viroid(PCFVd),potato spindle tuber viroid(PSTVd),tomato apical stunt viroid(TASVd),tomato chlorotic dwarf viroid(TCDVd),and tomato planta macho viroid(TPMVd),we developed a universal probe based on a highly conserved 61 nt long sequence shared among them.Compared with their specific probes,the universal probe has a similar,though slightly reduced,detection sensitivity and has the advantages of simple and cost-effective preparation and simultaneous detection of the six pospiviroids.In addition,the universal probe was used in dot-blot hybridization assays for a large-scale survey of viroid(s)in tomato plantings in China.Only PSTVd was detected in a few greenhouse-planted tomato plants.Sequence analysis revealed that these tomato PSTVd isolates may have been introduced from tomato seeds imported from abroad.
基金the National Key Technology R&D Program of China (2007BAD61B04)the National Natural Science Foundation of CQ CSTC, China (2006BB1351)
文摘Citrus viroids are the small but economically important RNA pathogens. For investigating their occurrence and distribution in China, 65 viroid samples collected from 8 major citrus cultivated regions were evaluated using one-step or multiplex onestep RT-PCR and biological indexing for specifically detection of Citrus exocortis viroid （CEVd）, Citrus bent leaf viroid （CBLVd）, Hop stunt viroid （HSVd）, Citrus viroid-Ⅲ （CVd-Ⅲ） and Citrus viroid-Ⅳ （CVd-Ⅳ）. The results showed that there were at least 4 kinds of citrus viroids （CEVd, CBLVd, HSVd, and CVd-Ⅲ） on citrus trees in China. Most of the infected citrus plants harbored more than one viroid species, and two plants were infected with up to 4 citrus viroids. Sweet orange was more frequently infected by viroids than other citrus varieties. It is the preliminary report on the species and distribution of citrus viroids in China.
基金supported by the China Agriculture Research System(CARS-10-P14)the National Science Foundation for Post-doctoral Scientists of China(20110491125)+2 种基金the Heilongjiang Funds for Distinguished Young Scientist,China (JC 201018)the Harbin Application Technology Research and Development Projects,China(2013AE6AW059)the Young Scientists Science Foundation of Heilongjiang Province,China(QC2015026)
文摘China is the largest potato producing country worldwide,with this crop representing the fourth largest staple food crop in China.However,the steady presence of Potato spindle tuber viroid（PSTVd） over the past five decades has a significant economic impact on potato production.To determine why PSTVd control measures have been ineffective in China,more than 1 000 seed potatoes collected between 2009 and 2014 were subjected to PSTVd detection at the Supervision and Testing Center for Virus-free Seed Potatoes Quality,Ministry of Agriculture,China.A high PSTVd infection rate（6.5%） was detected among these commercial seed potatoes.Some breeding lines of potato collected from 2012 to 2015 were also tested for PSTVd infection,revealing a high rate of PSTVd contamination in these potato propagation materials.Furthermore,comparison of the full-length sequences of 71 different Chinese PSTVd isolates revealed a total of 74 predominant PSTVd variants,which represented 42 different sequence variants of PSTVd.Comparative sequence analysis revealed 30 novel PSTVd sequence variants specific to China.Comprehensive phylogenetic analysis uncovered a close relationship between the Chinese PSTVd sequence variants and those isolated from Russia.It is worth noting that three intermediate strains and six mild strains were identified among these variants.These results have important implications for explaining the ineffective control of PSTVd in China and thus could serve as a basic reference for designing more effective measures to eliminate PSTVd from China in the future.
基金supported by the Major Scientific and Technical Project in Hunan Province, China(04NK1005)
文摘Total RNA was isolated from the phloem of young shoots and retro-transcripted to cDNA by reverse transcriptasepolymerase chain reaction （RT-PCR） with specific primers; the amplified cDNA fragments were sequenced for identification of subtypes. In this study, an effective RT-PCR technique was established for detecting citrus viroids, and three citrus viroids were recognized, namely, CEVd, CVd-II, and CVd-III. The latter two were identified for the first time in China. The sequences of CVd-Ⅱ were different from all the three subtypes reported in the GenBank and seemed to be a new subtype. CVd-Ⅲb detected in the present study could be further developed as a dwarfing agent.
基金Supported by Doctoral Research Startup Project of Zhaotong University。
文摘Potato spindle tuber viroid(PSTVd)disease is one of the major diseases that threatens potato production.Therefore,an advanced,rapid and sensitive detection technology is needed to detect the disease for better control.In order to establish an easier nucleic acid spot hybridization(NASH)method,some studies were tried as the followings:(1)the pre-hybridization step of nucleic acid spot hybridization(NASH)was omitted compared with ordinary way;(2)RNA extraction(phenol extraction and Ames buffer extraction)methods were compared;(3)fixed RNA by UV lamp and oven compared with UV cross-linker;(4)hybridized the RNA in shaking incubator and so on.The results showed that RNA extracted by Ames buffer was more effective than by the phenol extraction method.Besides,the result of hybridization without pre-hybridization step was better than that with 1.5 h of pre-hybridization.The more important discovery was that the shaking incubator could replace the hybridization oven and the ordinary UV lamp could replace the UV cross-linker.After a long term repeated research and testing,a new hybridization system that could rapidly detect the PSTVd by improved NASH technique merely using common instruments and equipment was established.
文摘The viability of most tomato varieties cultivated in Libya have been tested to infect with potato spindle tuber viroid/potatoes （PSTVd） and its impact on growth and production of some of these varieties, which were mechanically inoculated with Libyan isolate of viroid PSTVd as follows： Vlkato, Sankarh, Lebda, Jasmine, Kenza and Hana. The percent of incidence were 95.95%, 90%, 90.80%, 80% and 20%, respectively. The following varieties have been contagious mechanically with viroid of PSTVd： Vlkato, zahra, Toria, Lebda, Hoda, Farwa, Alkaraz, Naziha, Rim Star and Kartika. The percent of incidence were 95.95%, 85%, 85.80%, 80%, 70.40%, 0.0%, 0.0%, respectively. The varied symptoms of wrinkle, twist, warp, swell the veins of the leaves, dark brown spots formation and a large yellow spots turned into white patches. Also the effect of the Egyptian isolate viroid PSTVd in the growth and production of varieties Jasmine, Lebda, Soberhalim, and treasure No. 185 had been studied, as the average rates of decline in the production of the fruits tomatoes/tomato 43.4% and 17% length of plants, and in the fresh weight and dry root of the sum of 35% and 37% respictively.
文摘Citrus viroids are small non-coding RNA pathogens that pose a significant threat to global citrus production by reducing fruit yield,quality,and tree longevity.Several viroids,including Citrus exocortis viroid(CEVd),Hop stunt viroid(HSVd),Citrus bent leaf viroid(CBLVd),and newly identified members such as Citrus Viroid VI(CVd-VI)and Citrus Viroid VII(CVd-VII)have been reported from diverse citrus-growing regions.These pathogens are transmitted mainly through vegetative propagation,contaminated tools,and occasionally via seed or pollen,making their management complex.This review synthesizes current knowledge on the biology,structural diversity,transmission,symptomatology,detection,and economic impact of citrus viroids.In addition to compiling existing findings,it emphasizes critical challenges such as understanding host–pathogen molecular interactions,the implications of viroid infections under climate change,and the limited availability of resistant rootstocks.Recent advances in diagnostic tools,including Reverse Transcription Polymerase Chain Reaction(RT-PCR),Quantitative Polymerase Chain Reaction(qPCR),High-throughput sequencing(HTS),and in silico approaches,are evaluated alongside practical constraints in low-resource settings.Furthermore,the review highlights management strategies focused on certified planting material,sanitation,resistant genotypes,and integration into global citrus certification programs.By consolidating existing information while outlining key knowledge gaps and future directions,this work provides a foundation for developing sustainable strategies to mitigate the impact of viroids on the citrus industry.
文摘Wu M,Li W,Hu N,Liu C,Li J,Li Y,et al.Discovery of a Novel Viroid-Like Circular RNA in Colorectal Cancer.Cancer Commun.2025;45(1):46-50.doi:10.1002/cac2.12626.This Expression of Concern is for the above article,published online on 09November 2024 in WileyOnline Library(wileyonlinelibrary.com),and has been issued by agreement between the journal Editor-in-Chief,Rui-Hua Xu;Sun Yat-sen University Cancer Center;and JohnWiley&Sons Australia.The Expression of Concern has been agreed upon following information provided by a third party regarding the identification of the CRC-associated viroid.The authors reported this viroid-like circRNA as absent from the human genome based on the hg38 reference.However,the sequence is present at chromosome13:96543662-96543775 in the more complete T2T human genome reference,indicating it is not an exogenous RNA element.The authors have acknowledged the need for further investigation,particularly in light of the discrepancies from the difference between the hg38 and T2T human genomes.The editors have decided to issue this Expression of Concern to alert readers as further investigations proceed.
