Verticillium wilt,caused by the notorious fungal pathogen Verticillium dahliae,is one of the main limiting factors for cotton production.Due to the stable dormant structure microsclerotia,long-term variability and co-...Verticillium wilt,caused by the notorious fungal pathogen Verticillium dahliae,is one of the main limiting factors for cotton production.Due to the stable dormant structure microsclerotia,long-term variability and co-evolution with host plant,its pathogenicity mechanism is very complicated,and the interaction mechanism between pathogen and host plant is also unclear.So identification and functional analysis of the genes involved in the pathogenicity or virulence of this fungus will benefit to uncover the molecular pathogenic mechanism of V.dahliae.In this review,many multifunction genes covering microsclerotia development,pathogen infection,effector proteins,transcription factors,horizontal gene transfer and trans-kingdom RNA silencing have been summarized to provide a theoretical basis to deep understand the molecular pathogenicity mechanism of V.dahliae and promote to effectively control Verticillium wilt.Furtherly,these pathogenicity-related genes may be considered as targets for effective control of Verticillium wilt in cotton.展开更多
Identification of powdery mildew pathogens on melon（Cucumis melo） is important for melon breeding and diseaseresistant germplasm selection. In this study, a powdery mildew pathogen that infected melon plants in Heil...Identification of powdery mildew pathogens on melon（Cucumis melo） is important for melon breeding and diseaseresistant germplasm selection. In this study, a powdery mildew pathogen that infected melon plants in Heilongjiang Province, China, was investigated in terms of host identification, morphological characteristics and phylogenetic relationships. The morphological characteristics of the pathogen were observed at five phases in the life cycle： germinating conidia, primary germ tube, hyphae, conidiophores, and colonization. The conidia were elliptical, colorless, catenulate, and the average length was 29.07 μm and average width was 17.82 μm. One ascus and eight ascospores were produced. DNA was extracted from 0.01 g conidiophores from a strain of powdery mildew pathogen that infected melon. ITS ribosomal DNA region（524 bp） was amplified with the universal ITS1 and ITS4 primers. The nucleotide sequence showed 100% similarity with ITS sequences for three Podosphaera fusca strains obtained from the GenBank database. The identity of the pathogen was confirmed as Sphaerotheca fuliginea. International standard differential hosts were used to identify S. fuliginea strain as 2F race. These results supported the notion that Podosphaera fusca was a synonym of S. fuliginea.展开更多
Cotton diseases represent a major challenge to cotton growth.Cloning of a cotton pathogen response gene and promoter is of great importance to improve disease resistance.In this study,a
In order to determine the effect of foreign genes on a transgenic parasite,the pathogenicity and development in chickens of transgenic E.tenella strain TE1,which expresses yellow fluorescent protein (YFP) and dihydrof...In order to determine the effect of foreign genes on a transgenic parasite,the pathogenicity and development in chickens of transgenic E.tenella strain TE1,which expresses yellow fluorescent protein (YFP) and dihydrofolate reductase thymidylate synthase derived from Toxoplasma gondii(TgDHFR-TS), were compared with that of the parental strain BJ.Results indicated that the fecundity of the transgenic parasite(TE1) was reduced at least 4 times relative to that of the BJ strain.Low dosage of the TE1 strain induced less pathogenesis in chickens than did the BJ strain,but chickens inoculated with a higher dosage of TE1 oocysts displayed severe pathogenicity and mortality as did the BJ strain.In addition,trophozoites, the first generation and the second generation meronts and merozoites,microgamonts and macrogamonts of the transgenic parasite TE1 were seen by fluorescence microscopy.More interestingly,not all four sporonts in the sporulating transgenic oocysts express YFP.These findings suggest that the expression of YFP and TgDHFR-TS genes to some extent reduced pathogenicity and reproductive potential of transgenic E.tenella.Recombination between homologous or non-homologous chromosomes occurred during zygotic meiosis in E.tenella strain TE1.展开更多
[Objectives]Lotus(Nelumbo nucifera Gaertn)is an economically important aquatic plant in China.Fungal disease is a serious problem in lotus cultivation.In this study,the pathogenic fungi on lotus in Nanchang City were ...[Objectives]Lotus(Nelumbo nucifera Gaertn)is an economically important aquatic plant in China.Fungal disease is a serious problem in lotus cultivation.In this study,the pathogenic fungi on lotus in Nanchang City were investigated to lay the foundation for the disease control.[Methods]Lotus leaves and stems in ponds of Nanchang City were collected,the fungi on leave/stem spots were isolated and purified.Colonies morphological characters and ITS sequences were used to identify the strains.[Results]49 strains were isolated and identified to 20 species,belonging to 12 genera.[Discussion]15 species may firstly be reported on lotus in this study,i.e.,Alternaria angustiovoidea,Alternaria compacta,Alternaria ricini,Alternaria tenuissima,Arthrinium arundinis,Botryosphaeria dothidea,Curvularia spicifera,Diaporthe australiana,Diaporthe eres,Diaporthe tectonae,Epicoccum nigrum,Fusarium fujikuroi,Neofusicoccum parvum,Nigrospora sphaerica,and Phomopsis eucommii.展开更多
Yersinia enterocolitica is an important zoonotic pathogen that can induce disease outbreaks in a wide host range. Strain YER6022 was isolated from Pelteobagrus vachelli and identified using bacterial morphology and 16...Yersinia enterocolitica is an important zoonotic pathogen that can induce disease outbreaks in a wide host range. Strain YER6022 was isolated from Pelteobagrus vachelli and identified using bacterial morphology and 16S rDNA sequence analysis. Five virulence factors were detected, then artificial infection experiment and histopathological method were carried out. These results showed that strain YER6022 was one of Y. enterocolitica family members. In addition, ail, ystb, virF, yadA and HPIint were dectected. In artificial infection experiment, with 80% mortality and 100% morbidity, injected Pelteobagrus vachellis showed red swollen of the anus, abdomen swelling and fim bleeding. There existed serious hyperaemia and edema in kidney, spleen, intestine and liver at the light microscope. Ultrastructural observation indicated that mitochondria of the liver, kidney, spleen and intestine swelled and mitochondrial cristae broke. The data had further shed light on its pathogenicity in Pelteobagrus vachelli. It would benefit for further studies on pathogenesis ofPelteobagrus vachelli infected with Y. enterocolitica.展开更多
The disinfected bacteria will be a photoreactivation under the irradiation of the sunlight,and the light intensity plays an important role in the bacteria resurrection.The effect of light intensity on photoreactivatio...The disinfected bacteria will be a photoreactivation under the irradiation of the sunlight,and the light intensity plays an important role in the bacteria resurrection.The effect of light intensity on photoreactivation of Escherichia coli(E.coli) and Enterococcus faecalis(E.faecalis) in secondary effluents which were disinfected respectively by pure UV and UV-TiO_2 was investigated.The results show that the disinfection efficiency of UV-TiO_2 is much higher than that of the pure UV disinfection.The photoreactivation rate of E.coli is much higher in pure UV disinfection than in UV-TiO_2 photocatalytic disinfection.Under high light intensity in UV-TiO_2 disinfection,high resurrection rate can be induced.However,a higher resurrection rate can be introduced even under low light intensity in pure UV disinfection alone.Meanwhile,UV-TiO_2 disinfection has a strong inhibition effect on E.faecalis photoreactivation.When the light intensity is lower than 21 μW/cm^2,nearly no resurrection of E.faecalis occurs after 72 h resurrection irradiation,and a little resurrection rate is observed only under a strong photoreactivating light intensity.展开更多
Identification of plant-pathogenic fungi is time-consuming due to cultivation and microscopic examination and can be influenced by the interpretation of the micro-morphological characters observed.The present investig...Identification of plant-pathogenic fungi is time-consuming due to cultivation and microscopic examination and can be influenced by the interpretation of the micro-morphological characters observed.The present investigation aimed to create a simple but sophisticated method for the identification of plant-pathogenic fungi by Fourier transform infrared(FTIR)spectroscopy.In this study,FTIR-attenuated total reflectance(ATR)spectroscopy was used in combination with chemometric analysis for identification of important pathogenic fungi of horticultural plants.Mixtures of mycelia and spores from 27fungal strains belonging to nine different families were collected from liquid PD or solid PDA media cultures and subjected to FTIR-ATR spectroscopy measurements.The FTIR-ATR spectra ranging from 4 000to 400cm-1 were obtained.To classify the FTIRATR spectra,cluster analysis was compared with canonical vitiate analysis(CVA)in the spectral regions of3 050~2 800and 1 800~900cm-1.Results showed that the identification accuracies achieved 97.53%and99.18%for the cluster analysis and CVA analysis,respectively,demonstrating the high potential of this technique for fungal strain identification.展开更多
目的分析北京地区秋冬季急性呼吸道感染的流行特征,为急性呼吸道感染疾病的防控和诊治提供依据。方法采用便利抽样法,以北京协和医院2023年9月—2024年2月因急性呼吸道感染就诊的患者为研究对象。采集患者鼻咽拭子标本,采用荧光定量PCR...目的分析北京地区秋冬季急性呼吸道感染的流行特征,为急性呼吸道感染疾病的防控和诊治提供依据。方法采用便利抽样法,以北京协和医院2023年9月—2024年2月因急性呼吸道感染就诊的患者为研究对象。采集患者鼻咽拭子标本,采用荧光定量PCR法检测6种常见呼吸道病原体[包括甲型流感病毒(influenza A virus,FluA)、乙型流感病毒(influenza B virus,FluB)、人鼻病毒(human rhinovirus,HRV)、肺炎支原体(Mycoplasma pneumoniae,MP)、呼吸道合胞病毒(respiratory syncytial virus,RSV)、腺病毒(adenovirus,ADV)]和新型冠状病毒感染情况,对病原体感染分布特征进行分析。结果共入选符合标准的患者5556例,6种常见呼吸道病原体总体阳性率为63.7%,单一病原体阳性率为54.0%,2种病原体阳性率为8.9%,3种及以上病原体阳性率为0.7%。整体检出病原体以FluA和RSV为主,阳性率依次为16.1%和15.7%;ADV、MP、HRV和FluB阳性率接近,分别为11.1%、11.1%、10.0%和10.0%。病原体总体阳性率在性别间无显著性差异,但在秋冬季节间(χ^(2)=34.617,P<0.001)以及儿童、中青年和老年患者间(χ^(2)=422.38,P<0.001)存在统计学差异。其中,MP(χ^(2)=8.647,P=0.003)、FluA(χ^(2)=131.932,P<0.001)和HRV(χ^(2)=174.199,P<0.001)在秋季的阳性率显著高于冬季,而FluB在冬季的阳性率显著高于秋季(χ^(2)=287.894,P<0.001);儿童组MP、RSV、HRV和ADV的阳性率均显著高于中青年和老年患者(P均<0.001),而FluB在中青年患者中的阳性率则显著高于儿童和老年患者(P均<0.001)。6种常见呼吸道病原体在新型冠状病毒感染流行时期阳性率明显下降,表现为非同步季节性模式。结论北京地区呼吸道病原体流行情况与年龄、季节有关,需在不同季节、针对不同重点人群开展有针对性的预防措施。展开更多
基金supported by the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural SciencesCentral Publicinterest Scientific Institution Basal Research Fund (No. 1610162021031).
文摘Verticillium wilt,caused by the notorious fungal pathogen Verticillium dahliae,is one of the main limiting factors for cotton production.Due to the stable dormant structure microsclerotia,long-term variability and co-evolution with host plant,its pathogenicity mechanism is very complicated,and the interaction mechanism between pathogen and host plant is also unclear.So identification and functional analysis of the genes involved in the pathogenicity or virulence of this fungus will benefit to uncover the molecular pathogenic mechanism of V.dahliae.In this review,many multifunction genes covering microsclerotia development,pathogen infection,effector proteins,transcription factors,horizontal gene transfer and trans-kingdom RNA silencing have been summarized to provide a theoretical basis to deep understand the molecular pathogenicity mechanism of V.dahliae and promote to effectively control Verticillium wilt.Furtherly,these pathogenicity-related genes may be considered as targets for effective control of Verticillium wilt in cotton.
基金Supported by the Earmarked Fund for Modern Agro-industry Technology Research System(CARS-26-02)the National Natural Science Foundation(31000917)Heilongjiang Excellent Young Funding(JC200712)
文摘Identification of powdery mildew pathogens on melon（Cucumis melo） is important for melon breeding and diseaseresistant germplasm selection. In this study, a powdery mildew pathogen that infected melon plants in Heilongjiang Province, China, was investigated in terms of host identification, morphological characteristics and phylogenetic relationships. The morphological characteristics of the pathogen were observed at five phases in the life cycle： germinating conidia, primary germ tube, hyphae, conidiophores, and colonization. The conidia were elliptical, colorless, catenulate, and the average length was 29.07 μm and average width was 17.82 μm. One ascus and eight ascospores were produced. DNA was extracted from 0.01 g conidiophores from a strain of powdery mildew pathogen that infected melon. ITS ribosomal DNA region（524 bp） was amplified with the universal ITS1 and ITS4 primers. The nucleotide sequence showed 100% similarity with ITS sequences for three Podosphaera fusca strains obtained from the GenBank database. The identity of the pathogen was confirmed as Sphaerotheca fuliginea. International standard differential hosts were used to identify S. fuliginea strain as 2F race. These results supported the notion that Podosphaera fusca was a synonym of S. fuliginea.
文摘Cotton diseases represent a major challenge to cotton growth.Cloning of a cotton pathogen response gene and promoter is of great importance to improve disease resistance.In this study,a
基金supported by the National High Technology Research and Development Program of China(Project No. 2006AA02Z458)the Doctor Startup Foundation of Henan University of Science and Technology(09001350)
文摘In order to determine the effect of foreign genes on a transgenic parasite,the pathogenicity and development in chickens of transgenic E.tenella strain TE1,which expresses yellow fluorescent protein (YFP) and dihydrofolate reductase thymidylate synthase derived from Toxoplasma gondii(TgDHFR-TS), were compared with that of the parental strain BJ.Results indicated that the fecundity of the transgenic parasite(TE1) was reduced at least 4 times relative to that of the BJ strain.Low dosage of the TE1 strain induced less pathogenesis in chickens than did the BJ strain,but chickens inoculated with a higher dosage of TE1 oocysts displayed severe pathogenicity and mortality as did the BJ strain.In addition,trophozoites, the first generation and the second generation meronts and merozoites,microgamonts and macrogamonts of the transgenic parasite TE1 were seen by fluorescence microscopy.More interestingly,not all four sporonts in the sporulating transgenic oocysts express YFP.These findings suggest that the expression of YFP and TgDHFR-TS genes to some extent reduced pathogenicity and reproductive potential of transgenic E.tenella.Recombination between homologous or non-homologous chromosomes occurred during zygotic meiosis in E.tenella strain TE1.
基金Key projects of the Natural Science Foundation of Jiangxi Provincial Department of Education(GJJ190168)Advantages of Technological Innovation Teambuilding Program of Nanchang City,Innovation and Entrepreneurship Training Program of Jiangxi Agricultural University in 2020(No.147)。
文摘[Objectives]Lotus(Nelumbo nucifera Gaertn)is an economically important aquatic plant in China.Fungal disease is a serious problem in lotus cultivation.In this study,the pathogenic fungi on lotus in Nanchang City were investigated to lay the foundation for the disease control.[Methods]Lotus leaves and stems in ponds of Nanchang City were collected,the fungi on leave/stem spots were isolated and purified.Colonies morphological characters and ITS sequences were used to identify the strains.[Results]49 strains were isolated and identified to 20 species,belonging to 12 genera.[Discussion]15 species may firstly be reported on lotus in this study,i.e.,Alternaria angustiovoidea,Alternaria compacta,Alternaria ricini,Alternaria tenuissima,Arthrinium arundinis,Botryosphaeria dothidea,Curvularia spicifera,Diaporthe australiana,Diaporthe eres,Diaporthe tectonae,Epicoccum nigrum,Fusarium fujikuroi,Neofusicoccum parvum,Nigrospora sphaerica,and Phomopsis eucommii.
基金Supported by the Science&Technology Department of Sichuan Province(2013FZ0014)the Construction Project of the Postgraduate Academic Degree in Southwest University for Nationalities(2013XWD-S071007)
文摘Yersinia enterocolitica is an important zoonotic pathogen that can induce disease outbreaks in a wide host range. Strain YER6022 was isolated from Pelteobagrus vachelli and identified using bacterial morphology and 16S rDNA sequence analysis. Five virulence factors were detected, then artificial infection experiment and histopathological method were carried out. These results showed that strain YER6022 was one of Y. enterocolitica family members. In addition, ail, ystb, virF, yadA and HPIint were dectected. In artificial infection experiment, with 80% mortality and 100% morbidity, injected Pelteobagrus vachellis showed red swollen of the anus, abdomen swelling and fim bleeding. There existed serious hyperaemia and edema in kidney, spleen, intestine and liver at the light microscope. Ultrastructural observation indicated that mitochondria of the liver, kidney, spleen and intestine swelled and mitochondrial cristae broke. The data had further shed light on its pathogenicity in Pelteobagrus vachelli. It would benefit for further studies on pathogenesis ofPelteobagrus vachelli infected with Y. enterocolitica.
基金Projects(51174090,51168026)supported by the National Natural Science Foundation of China
文摘The disinfected bacteria will be a photoreactivation under the irradiation of the sunlight,and the light intensity plays an important role in the bacteria resurrection.The effect of light intensity on photoreactivation of Escherichia coli(E.coli) and Enterococcus faecalis(E.faecalis) in secondary effluents which were disinfected respectively by pure UV and UV-TiO_2 was investigated.The results show that the disinfection efficiency of UV-TiO_2 is much higher than that of the pure UV disinfection.The photoreactivation rate of E.coli is much higher in pure UV disinfection than in UV-TiO_2 photocatalytic disinfection.Under high light intensity in UV-TiO_2 disinfection,high resurrection rate can be induced.However,a higher resurrection rate can be introduced even under low light intensity in pure UV disinfection alone.Meanwhile,UV-TiO_2 disinfection has a strong inhibition effect on E.faecalis photoreactivation.When the light intensity is lower than 21 μW/cm^2,nearly no resurrection of E.faecalis occurs after 72 h resurrection irradiation,and a little resurrection rate is observed only under a strong photoreactivating light intensity.
基金the National Natural Science Foundation of China(31201473)the Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-IVFCAAS)funded by the Key Laboratory of Biology and Genetic Improvement of Horticultural Crops,Ministry of Agriculture,P.R.China
文摘Identification of plant-pathogenic fungi is time-consuming due to cultivation and microscopic examination and can be influenced by the interpretation of the micro-morphological characters observed.The present investigation aimed to create a simple but sophisticated method for the identification of plant-pathogenic fungi by Fourier transform infrared(FTIR)spectroscopy.In this study,FTIR-attenuated total reflectance(ATR)spectroscopy was used in combination with chemometric analysis for identification of important pathogenic fungi of horticultural plants.Mixtures of mycelia and spores from 27fungal strains belonging to nine different families were collected from liquid PD or solid PDA media cultures and subjected to FTIR-ATR spectroscopy measurements.The FTIR-ATR spectra ranging from 4 000to 400cm-1 were obtained.To classify the FTIRATR spectra,cluster analysis was compared with canonical vitiate analysis(CVA)in the spectral regions of3 050~2 800and 1 800~900cm-1.Results showed that the identification accuracies achieved 97.53%and99.18%for the cluster analysis and CVA analysis,respectively,demonstrating the high potential of this technique for fungal strain identification.
文摘目的分析北京地区秋冬季急性呼吸道感染的流行特征,为急性呼吸道感染疾病的防控和诊治提供依据。方法采用便利抽样法,以北京协和医院2023年9月—2024年2月因急性呼吸道感染就诊的患者为研究对象。采集患者鼻咽拭子标本,采用荧光定量PCR法检测6种常见呼吸道病原体[包括甲型流感病毒(influenza A virus,FluA)、乙型流感病毒(influenza B virus,FluB)、人鼻病毒(human rhinovirus,HRV)、肺炎支原体(Mycoplasma pneumoniae,MP)、呼吸道合胞病毒(respiratory syncytial virus,RSV)、腺病毒(adenovirus,ADV)]和新型冠状病毒感染情况,对病原体感染分布特征进行分析。结果共入选符合标准的患者5556例,6种常见呼吸道病原体总体阳性率为63.7%,单一病原体阳性率为54.0%,2种病原体阳性率为8.9%,3种及以上病原体阳性率为0.7%。整体检出病原体以FluA和RSV为主,阳性率依次为16.1%和15.7%;ADV、MP、HRV和FluB阳性率接近,分别为11.1%、11.1%、10.0%和10.0%。病原体总体阳性率在性别间无显著性差异,但在秋冬季节间(χ^(2)=34.617,P<0.001)以及儿童、中青年和老年患者间(χ^(2)=422.38,P<0.001)存在统计学差异。其中,MP(χ^(2)=8.647,P=0.003)、FluA(χ^(2)=131.932,P<0.001)和HRV(χ^(2)=174.199,P<0.001)在秋季的阳性率显著高于冬季,而FluB在冬季的阳性率显著高于秋季(χ^(2)=287.894,P<0.001);儿童组MP、RSV、HRV和ADV的阳性率均显著高于中青年和老年患者(P均<0.001),而FluB在中青年患者中的阳性率则显著高于儿童和老年患者(P均<0.001)。6种常见呼吸道病原体在新型冠状病毒感染流行时期阳性率明显下降,表现为非同步季节性模式。结论北京地区呼吸道病原体流行情况与年龄、季节有关,需在不同季节、针对不同重点人群开展有针对性的预防措施。
