Tomato brown rugose fruit virus(ToBRFV) is a novel tobamovirus firstly reported in 2015 and poses a severe threat to the tomato industry. So far, it has spread to 10 countries in America, Asia, and Europe. In 2019, To...Tomato brown rugose fruit virus(ToBRFV) is a novel tobamovirus firstly reported in 2015 and poses a severe threat to the tomato industry. So far, it has spread to 10 countries in America, Asia, and Europe. In 2019, ToBRFV was identified in Shandong Province(ToBRFV-SD), China. In this study, it was shown that ToBRFV-SD induced mild to severe mosaic and blistering on leaves, necrosis on sepals and pedicles, and deformation, yellow spots, and brown rugose necrotic lesions on fruits. ToBRFV-SD induced distinct symptoms on plants of tomato, Capsicum annumm, and Nicotiana benthamiana, and caused latent infection on plants of Solanum tuberosum, Solanum melongena, and N. tabacum cv. Zhongyan 102. All the 50 tomato cultivars tested were highly sensitive to ToBRFV-SD. The complete genomic sequence of ToBRFV-SD shared the highest nucleotide and amino acid identities with isolate IL from Israel. In the phylogenetic tree constructed with the complete genomic sequence, all the ToBRFV isolates were clustered together and formed a sister branch with tobacco mosaic virus(TMV). Furthermore, a quadruplex RT-PCR system was developed that could differentiate ToBRFV from other economically important viruses affecting tomatoes, such as TMV, tomato mosaic virus, and tomato spotted wilt virus. The findings of this study enhance our understanding of the biological and molecular characteristics of ToBRFV and provide an efficient and effective detection method for multiple infections, which is helpful in the management of ToBRFV.展开更多
The taxonomy of the genus Colletotrichum has undergone tremendous changes over the last decade,with over 200 species being currently recognised and species complexes being informally used to cluster those species.Many...The taxonomy of the genus Colletotrichum has undergone tremendous changes over the last decade,with over 200 species being currently recognised and species complexes being informally used to cluster those species.Many of these species are important plant pathogens,some rather polyphagous and others host-specific,but several occur seldomly and some may in fact be ecologically endangered.Based mainly on literature from the past decade,in this work we review the occurrence,geographic distribution and host spectrum of currently recognised Colletotrichum species under phylogenetic,pathologi-cal/agronomic and ecological perspectives,providing a list arranged by Colletotrichum species and species complexes.A total of 257 species are listed and grouped into 15 species complexes.In this work we have recorded 1353 unique host species-Colletotrichum species association records from 720 hosts,with the Fabaceae as the family with higher number of hosts(52 host species)but with the Rosaceae as the family with the highest number of host species-Colletotrichum species association records(118 association records).According to occurrence data,88 species are common in nature,128 were considered as data deficient and 41 are threatened,some of which are likely extinct from nature and preserved only in cul-ture collections.Several species are relevant plant pathogens,in some cases geographically confined and thus of potential quarantine relevance.Based on the major changes that occurred on Colletotrichum taxonomy over the last decade,this work provides a comprehensive overview of occurrence data of Colletotrichum species,compiling host range and geographical distribution,with relevance for plant pathology and conservation mycology.The current taxonomic framework in Colle-totrichum is revealing numerous species but poses challenges to the employment of standard criteria for the evaluation of biological conservation of these fungi.We advocate that conservation mycology and taxonomy should find common routes simultaneously enabling the correct delimitation of species of Colletotrichum and the implementation of feasible criteria for the evaluation of conservation.The employment of new technologies,such whole genome sequencing(WGS),will help and support the description of new species and to gain a better understanding of the genetic bases of speciation processes.展开更多
Tomato mottle mosaic virus(ToMMV), an economically important species of the genus Tobamovirus, causes significant loss in yield and quality of tomato fruits. Here, we identified the Shandong isolate of ToMMV(ToMMV-SD)...Tomato mottle mosaic virus(ToMMV), an economically important species of the genus Tobamovirus, causes significant loss in yield and quality of tomato fruits. Here, we identified the Shandong isolate of ToMMV(ToMMV-SD) collected from symptomatic tomato fruits in Weifang, Shandong Province of China. ToMMV-SD caused symptoms such as severe mosaic, mottling, and necrosis of tomato leaves, yellow spot and necrotic lesions on tomato fruits. The obtained full genome of ToMMV-SD was 6 399 nucleotides(accession number MW373515) and had the highest identity of 99.5% with that of isolate SC13-051 from the United States of America at the genomic level. The infectious clone of ToMMV-SD was constructed and induced clear mosaic and necrotic symptoms onto Nicotiana benthamiana leaves. Several commercial tomato cultivars, harboring Tm-2~2 resistance gene, and pepper cultivars, containing L resistance gene, were susceptible to ToMMV-SD. Plants of Solanum melongena(eggplant) and Brassica pekinensis(napa cabbage) showed mottling symptoms, while N. tabacum cv. Zhongyan 100 displayed latent infection. ToMMV-SD did not infect plants of N. tabacum cv. Xanthi NN, Brassica rapa ssp. chinensis(bok choy), Raphanus sativus(radish), Vigna unguiculata cv. Yuanzhong 28-2(cowpea), or Tm-2~2 transgenic N. benthamiana. A quintuplex RT-PCR system differentiated ToMMV from tomato mosaic virus, tomato brown rugose fruit virus, tobacco mosaic virus, and tomato spotted wilt virus, with the threshold amount of 0.02 pg. These results highlight the threat posed by ToMMV to tomato and pepper cultivation and offer an efficient detection system for the simultaneous detection of four tobamoviruses and tomato spotted wilt virus infecting tomato plants in the field.展开更多
Tristeza is a devastating viral disease in all the citrus growing countries throughout the world and has killed millions of citrus trees in severely affected orchards.The citrus species grafted on sour orange rootstoc...Tristeza is a devastating viral disease in all the citrus growing countries throughout the world and has killed millions of citrus trees in severely affected orchards.The citrus species grafted on sour orange rootstock are affected by this disease.Predominantly,the sweet orange,grapefruit and lime trees grafted on sour orange exhibit severe symptoms like quick decline,vein clearing,pin holing,bark scaling and degeneration leading to variable symptoms.Symptomatic expression of Citrus tristeza virus(CTV)in different hosts has been attributed to virus isolates which are from severe to mild.Different serological and molecular assays have been deployed to differentiate the strains of CTV.Citrus tristeza virus is diversified towards its strains on the basis of biological,serological and molecular characterization.Phenotypic expression is due to genetic alteration and different molecular basis have now been adopted for strain differentiation.This review will give a brief idea about the different CTV isolates,their characterization based on nucleic acid and serological assays.Different methods along with salient features for strain characterization has also been reviewed.This review will also open the new aspects towards formulation of management strategies through different detection techniques.展开更多
The present opinion article, while dealing with the debated origin of “Severe Acute Respiratory Syndrome-Coronavirus-2” (SARS-CoV-2), the betacoronavirus responsible for “Corona Virus Disease-2019” (COVID-19), pro...The present opinion article, while dealing with the debated origin of “Severe Acute Respiratory Syndrome-Coronavirus-2” (SARS-CoV-2), the betacoronavirus responsible for “Corona Virus Disease-2019” (COVID-19), provides a speculative insight into the so-called “gain of function” (GOF), a process resulting in the acquirement of new phenotypic features on behalf of the viral pathogen. More in detail, a GOF-related phenomenon leading to increased SARS-CoV-2 virulence and/or transmissibility—as clearly exemplified by the “delta” and the “omicron” as well as by other “variants of concern”—would not necessarily imply that viral genetic manipulations made in the laboratory are its exclusive drivers, provided that GOF may also occur as a consequence of a natural selection process. In order to gain a better understanding of SARS-CoV-2 GOF and GOF-associated phenomena, an in-depth knowledge of the complex viral-host interaction dynamics is absolutely needed, while also paying special attention to the human-animal-viral ecological interfaces within an “ad hoc” multidisciplinary, “holistic”, scientific evidence-based and “One Health”-based approach.展开更多
Watermelon mosaic virus(WMV) is one of the major viruses infecting cucurbit crops worldwide. Although WMV is very common worldwide,little is known about the biological traits of WMV isolates from China. Hence, this st...Watermelon mosaic virus(WMV) is one of the major viruses infecting cucurbit crops worldwide. Although WMV is very common worldwide,little is known about the biological traits of WMV isolates from China. Hence, this study aimed to characterize 11 WMV isolates infecting melon from different geographical origins in Xinjiang based on experimental hosts. Sap inoculation of the 11 WMV isolates onto a range of 13 plant species revealed some differences compared to the WMV isolates collected from other countries. Our results showed that, overall, there were no obvious correlations of host responses to inoculation with WMV isolates from different geographical origins. However, isolate JS-1 caused mild mosaic on Cucurbita moschata, whereas the remaining 10 isolates were asymptomatic on this plant species. Moreover, in Datura stramonium, isolate TYG-1 induced mosaic, whereas the remaining 10 isolates did not infect this species. All isolates infected systemically Cucurbita pepo and Cucumis melo plants, causing severe symptoms. All isolates did not induce any symptoms on Cucumis sativus, but the virus could be detected using RT-PCR. Additionally, all isolates infected systemically Nicotiana tabacum plants, causing mild mosaics. Chenopodium amaranticolor and Chenopodium quinoa reacted to all isolates by chlorotic local lesions in the inoculated leaves, and the virus was detected in the inoculated leaves using RT-PCR. In addition, the attempts to transmit the isolates to Luffa cylindrica, Vicia faba, Phaseolus vulgaris, Vigna unguiculata or Pisum sativum failed as confirmed by negative RT-PCR. Our results would be useful for understanding the biological variability of WMV.展开更多
The persistent epidemic of human mpox, caused by mpox virus (MPXV), raises concerns about the future spread ofMPXV and other poxviruses. MPXV is a typical zoonotic virus which can infect human and cause smallpox-likes...The persistent epidemic of human mpox, caused by mpox virus (MPXV), raises concerns about the future spread ofMPXV and other poxviruses. MPXV is a typical zoonotic virus which can infect human and cause smallpox-likesymptoms. MPXV belongs to the Poxviridae family, which has a relatively broad host range from arthropods tovertebrates. Cross-species transmission of poxviruses among different hosts has been frequently reported andresulted in numerous epidemics. Poxviruses have a complex linear double-strand DNA genome that encodeshundreds of proteins. Genes related to the host range of poxvirus are called host range genes (HRGs). This reviewbriefly introduces the taxonomy, phylogeny and hosts of poxviruses, and then comprehensively summarizes thecurrent knowledge about the cross-species transmission of poxviruses. In particular, the HRGs of poxvirus aredescribed and their impacts on viral host range are discussed in depth. We hope that this review will provide acomprehensive perspective about the current progress of researches on cross-species transmission and HRGvariation of poxviruses, serving as a valuable reference for academic studies and disease control in the future.展开更多
The activated sludge process is characterized by high microbial density and diversity,both of which facilitate antibiotic resistance gene transfer.Many studies have suggested that antibiotic and non-antibiotic drugs a...The activated sludge process is characterized by high microbial density and diversity,both of which facilitate antibiotic resistance gene transfer.Many studies have suggested that antibiotic and non-antibiotic drugs at sub-inhibitory concentrations are major inducers of conjugative gene transfer.The self-transmissible plasmid pND6-2 is one of the endogenous plasmids harbored in Pseudomonas putida ND6,which can trigger the transfer of another co-occurring naphthalene-degrading plasmid pND6-1.Therefore,to illustrate the potential influence of stimulants on conjugative transfer of pND6-2,we evaluated the effects of four antibiotics (ampicillin,gentamycin,kanamycin,and tetracycline) and naphthalene,on the conjugal transfer efficiency of pND6-2 by filter-mating experiment.Our findings demonstrated that all stimulants within an optimal dose promoted conjugative transfer of pND6-2from Pseudomonas putida GKND6 to P.putida KT2440,with tetracycline being the most effective (100μg/L and 10μg/L),as it enhanced pND6-2-mediated intra-genera transfer by approximately one hundred-fold.Subsequently,seven AS reactors were constructed with the addition of donors and different stimulants to further elucidate the conjugative behavior of pND6-2 in natural environment.The stimulants positively affected the conjugal process of pND6-2,while donors reshaped the host abundance in the sludge.This was likely because stimulant addition enhanced the expression levels of conjugation transfer-related genes.Furthermore,Blastocatella and Chitinimonas were identified as the potential receptors of plasmid pND6-2,which was not affected by donor types.These findings demonstrate the positive role of sub-inhibitory stimulant treatment on pND6-2 conjugal transfer and the function of donors in re-shaping the host spectrum of pND6-2.展开更多
基金supported by the grants from the National Natural Science Foundation of China (31720103912 and 31801704)the ’Taishan Scholar’ Construction Project, China (TS201712023)。
文摘Tomato brown rugose fruit virus(ToBRFV) is a novel tobamovirus firstly reported in 2015 and poses a severe threat to the tomato industry. So far, it has spread to 10 countries in America, Asia, and Europe. In 2019, ToBRFV was identified in Shandong Province(ToBRFV-SD), China. In this study, it was shown that ToBRFV-SD induced mild to severe mosaic and blistering on leaves, necrosis on sepals and pedicles, and deformation, yellow spots, and brown rugose necrotic lesions on fruits. ToBRFV-SD induced distinct symptoms on plants of tomato, Capsicum annumm, and Nicotiana benthamiana, and caused latent infection on plants of Solanum tuberosum, Solanum melongena, and N. tabacum cv. Zhongyan 102. All the 50 tomato cultivars tested were highly sensitive to ToBRFV-SD. The complete genomic sequence of ToBRFV-SD shared the highest nucleotide and amino acid identities with isolate IL from Israel. In the phylogenetic tree constructed with the complete genomic sequence, all the ToBRFV isolates were clustered together and formed a sister branch with tobacco mosaic virus(TMV). Furthermore, a quadruplex RT-PCR system was developed that could differentiate ToBRFV from other economically important viruses affecting tomatoes, such as TMV, tomato mosaic virus, and tomato spotted wilt virus. The findings of this study enhance our understanding of the biological and molecular characteristics of ToBRFV and provide an efficient and effective detection method for multiple infections, which is helpful in the management of ToBRFV.
文摘The taxonomy of the genus Colletotrichum has undergone tremendous changes over the last decade,with over 200 species being currently recognised and species complexes being informally used to cluster those species.Many of these species are important plant pathogens,some rather polyphagous and others host-specific,but several occur seldomly and some may in fact be ecologically endangered.Based mainly on literature from the past decade,in this work we review the occurrence,geographic distribution and host spectrum of currently recognised Colletotrichum species under phylogenetic,pathologi-cal/agronomic and ecological perspectives,providing a list arranged by Colletotrichum species and species complexes.A total of 257 species are listed and grouped into 15 species complexes.In this work we have recorded 1353 unique host species-Colletotrichum species association records from 720 hosts,with the Fabaceae as the family with higher number of hosts(52 host species)but with the Rosaceae as the family with the highest number of host species-Colletotrichum species association records(118 association records).According to occurrence data,88 species are common in nature,128 were considered as data deficient and 41 are threatened,some of which are likely extinct from nature and preserved only in cul-ture collections.Several species are relevant plant pathogens,in some cases geographically confined and thus of potential quarantine relevance.Based on the major changes that occurred on Colletotrichum taxonomy over the last decade,this work provides a comprehensive overview of occurrence data of Colletotrichum species,compiling host range and geographical distribution,with relevance for plant pathology and conservation mycology.The current taxonomic framework in Colle-totrichum is revealing numerous species but poses challenges to the employment of standard criteria for the evaluation of biological conservation of these fungi.We advocate that conservation mycology and taxonomy should find common routes simultaneously enabling the correct delimitation of species of Colletotrichum and the implementation of feasible criteria for the evaluation of conservation.The employment of new technologies,such whole genome sequencing(WGS),will help and support the description of new species and to gain a better understanding of the genetic bases of speciation processes.
基金supported by the grants from the National Natural Science Foundation of China(32072387)the‘Taishan Scholar’Construction Project,China(TS201712023)。
文摘Tomato mottle mosaic virus(ToMMV), an economically important species of the genus Tobamovirus, causes significant loss in yield and quality of tomato fruits. Here, we identified the Shandong isolate of ToMMV(ToMMV-SD) collected from symptomatic tomato fruits in Weifang, Shandong Province of China. ToMMV-SD caused symptoms such as severe mosaic, mottling, and necrosis of tomato leaves, yellow spot and necrotic lesions on tomato fruits. The obtained full genome of ToMMV-SD was 6 399 nucleotides(accession number MW373515) and had the highest identity of 99.5% with that of isolate SC13-051 from the United States of America at the genomic level. The infectious clone of ToMMV-SD was constructed and induced clear mosaic and necrotic symptoms onto Nicotiana benthamiana leaves. Several commercial tomato cultivars, harboring Tm-2~2 resistance gene, and pepper cultivars, containing L resistance gene, were susceptible to ToMMV-SD. Plants of Solanum melongena(eggplant) and Brassica pekinensis(napa cabbage) showed mottling symptoms, while N. tabacum cv. Zhongyan 100 displayed latent infection. ToMMV-SD did not infect plants of N. tabacum cv. Xanthi NN, Brassica rapa ssp. chinensis(bok choy), Raphanus sativus(radish), Vigna unguiculata cv. Yuanzhong 28-2(cowpea), or Tm-2~2 transgenic N. benthamiana. A quintuplex RT-PCR system differentiated ToMMV from tomato mosaic virus, tomato brown rugose fruit virus, tobacco mosaic virus, and tomato spotted wilt virus, with the threshold amount of 0.02 pg. These results highlight the threat posed by ToMMV to tomato and pepper cultivation and offer an efficient detection system for the simultaneous detection of four tobamoviruses and tomato spotted wilt virus infecting tomato plants in the field.
文摘Tristeza is a devastating viral disease in all the citrus growing countries throughout the world and has killed millions of citrus trees in severely affected orchards.The citrus species grafted on sour orange rootstock are affected by this disease.Predominantly,the sweet orange,grapefruit and lime trees grafted on sour orange exhibit severe symptoms like quick decline,vein clearing,pin holing,bark scaling and degeneration leading to variable symptoms.Symptomatic expression of Citrus tristeza virus(CTV)in different hosts has been attributed to virus isolates which are from severe to mild.Different serological and molecular assays have been deployed to differentiate the strains of CTV.Citrus tristeza virus is diversified towards its strains on the basis of biological,serological and molecular characterization.Phenotypic expression is due to genetic alteration and different molecular basis have now been adopted for strain differentiation.This review will give a brief idea about the different CTV isolates,their characterization based on nucleic acid and serological assays.Different methods along with salient features for strain characterization has also been reviewed.This review will also open the new aspects towards formulation of management strategies through different detection techniques.
文摘The present opinion article, while dealing with the debated origin of “Severe Acute Respiratory Syndrome-Coronavirus-2” (SARS-CoV-2), the betacoronavirus responsible for “Corona Virus Disease-2019” (COVID-19), provides a speculative insight into the so-called “gain of function” (GOF), a process resulting in the acquirement of new phenotypic features on behalf of the viral pathogen. More in detail, a GOF-related phenomenon leading to increased SARS-CoV-2 virulence and/or transmissibility—as clearly exemplified by the “delta” and the “omicron” as well as by other “variants of concern”—would not necessarily imply that viral genetic manipulations made in the laboratory are its exclusive drivers, provided that GOF may also occur as a consequence of a natural selection process. In order to gain a better understanding of SARS-CoV-2 GOF and GOF-associated phenomena, an in-depth knowledge of the complex viral-host interaction dynamics is absolutely needed, while also paying special attention to the human-animal-viral ecological interfaces within an “ad hoc” multidisciplinary, “holistic”, scientific evidence-based and “One Health”-based approach.
基金supported by the National Natural Science Foundation of China (Grant No. 31260258)the Innovative Project of Xinjiang University, China (Grant No. XJUBSCX-2012025)
文摘Watermelon mosaic virus(WMV) is one of the major viruses infecting cucurbit crops worldwide. Although WMV is very common worldwide,little is known about the biological traits of WMV isolates from China. Hence, this study aimed to characterize 11 WMV isolates infecting melon from different geographical origins in Xinjiang based on experimental hosts. Sap inoculation of the 11 WMV isolates onto a range of 13 plant species revealed some differences compared to the WMV isolates collected from other countries. Our results showed that, overall, there were no obvious correlations of host responses to inoculation with WMV isolates from different geographical origins. However, isolate JS-1 caused mild mosaic on Cucurbita moschata, whereas the remaining 10 isolates were asymptomatic on this plant species. Moreover, in Datura stramonium, isolate TYG-1 induced mosaic, whereas the remaining 10 isolates did not infect this species. All isolates infected systemically Cucurbita pepo and Cucumis melo plants, causing severe symptoms. All isolates did not induce any symptoms on Cucumis sativus, but the virus could be detected using RT-PCR. Additionally, all isolates infected systemically Nicotiana tabacum plants, causing mild mosaics. Chenopodium amaranticolor and Chenopodium quinoa reacted to all isolates by chlorotic local lesions in the inoculated leaves, and the virus was detected in the inoculated leaves using RT-PCR. In addition, the attempts to transmit the isolates to Luffa cylindrica, Vicia faba, Phaseolus vulgaris, Vigna unguiculata or Pisum sativum failed as confirmed by negative RT-PCR. Our results would be useful for understanding the biological variability of WMV.
基金funded by the National Natural Science Foundation of China(U2002218)the Hunan University Fund(521119400156).
文摘The persistent epidemic of human mpox, caused by mpox virus (MPXV), raises concerns about the future spread ofMPXV and other poxviruses. MPXV is a typical zoonotic virus which can infect human and cause smallpox-likesymptoms. MPXV belongs to the Poxviridae family, which has a relatively broad host range from arthropods tovertebrates. Cross-species transmission of poxviruses among different hosts has been frequently reported andresulted in numerous epidemics. Poxviruses have a complex linear double-strand DNA genome that encodeshundreds of proteins. Genes related to the host range of poxvirus are called host range genes (HRGs). This reviewbriefly introduces the taxonomy, phylogeny and hosts of poxviruses, and then comprehensively summarizes thecurrent knowledge about the cross-species transmission of poxviruses. In particular, the HRGs of poxvirus aredescribed and their impacts on viral host range are discussed in depth. We hope that this review will provide acomprehensive perspective about the current progress of researches on cross-species transmission and HRGvariation of poxviruses, serving as a valuable reference for academic studies and disease control in the future.
基金supported by the National Natural Science Foundation of China(No. 31670512)Natural Science Basic Research Plan in Shaanxi Province of China(No. 2018JM3039)。
文摘The activated sludge process is characterized by high microbial density and diversity,both of which facilitate antibiotic resistance gene transfer.Many studies have suggested that antibiotic and non-antibiotic drugs at sub-inhibitory concentrations are major inducers of conjugative gene transfer.The self-transmissible plasmid pND6-2 is one of the endogenous plasmids harbored in Pseudomonas putida ND6,which can trigger the transfer of another co-occurring naphthalene-degrading plasmid pND6-1.Therefore,to illustrate the potential influence of stimulants on conjugative transfer of pND6-2,we evaluated the effects of four antibiotics (ampicillin,gentamycin,kanamycin,and tetracycline) and naphthalene,on the conjugal transfer efficiency of pND6-2 by filter-mating experiment.Our findings demonstrated that all stimulants within an optimal dose promoted conjugative transfer of pND6-2from Pseudomonas putida GKND6 to P.putida KT2440,with tetracycline being the most effective (100μg/L and 10μg/L),as it enhanced pND6-2-mediated intra-genera transfer by approximately one hundred-fold.Subsequently,seven AS reactors were constructed with the addition of donors and different stimulants to further elucidate the conjugative behavior of pND6-2 in natural environment.The stimulants positively affected the conjugal process of pND6-2,while donors reshaped the host abundance in the sludge.This was likely because stimulant addition enhanced the expression levels of conjugation transfer-related genes.Furthermore,Blastocatella and Chitinimonas were identified as the potential receptors of plasmid pND6-2,which was not affected by donor types.These findings demonstrate the positive role of sub-inhibitory stimulant treatment on pND6-2 conjugal transfer and the function of donors in re-shaping the host spectrum of pND6-2.
