Apple leaf spot,caused by the Alternaria alternata apple pathotype(AAAP),is an important fungal disease of apple.To understand the molecular basis of resistance and pathogenesis in apple leaf spot,the transcriptomes o...Apple leaf spot,caused by the Alternaria alternata apple pathotype(AAAP),is an important fungal disease of apple.To understand the molecular basis of resistance and pathogenesis in apple leaf spot,the transcriptomes of two apple cultivars‘Hanfu'(HF)(resistant)and‘Golden Delicious'(GD)(susceptible)were analyzed at 0,6,18,24 and 48 h after AAAP inoculation by RNA-Seq.At each time point,a large number of significantly differentially expressed genes(DEGs)were screened between AAAP-inoculated and uninoculated apple leaves.Analysis of the common DEGs at four time points revealed significant differences in the resistance of‘HF'and‘GD'apple to AAAP infection.RLP,RNL,and JA signal-related genes were upregulated in both cultivars to restrict AAAP development.However,genes encoding CNLs,TNLs,WRKYs,and AP2s were only activated in‘HF'as part of the resistance response,of which,some play major roles in the regulation of ET and SA signal transduction.Further analysis showed that many DEGs with opposite expression trends in the two hosts may play important regulatory roles in response to AAAP infection.Transient expression of one such gene MdERF110 in‘GD'apple leaves improved AAAP resistance.Collectively,this study highlights the reasons for differential resistance to AAAP infection between‘HF'and‘GD'apples which can theoretically assist the molecular breeding of disease-resistant apple crops.展开更多
In recent years,the strong virulence pathotype Ⅴ of rice bacterial blight grew up quickly in Southern China,which has become a major population and spread to the rice regions of Jiangsu and Zhejiang provinces in Sout...In recent years,the strong virulence pathotype Ⅴ of rice bacterial blight grew up quickly in Southern China,which has become a major population and spread to the rice regions of Jiangsu and Zhejiang provinces in Southern China.Since pathotype Ⅴ caused serious bacterial blight disease in rice production regions,it is urgent to breed and promote resistant varieties against pathotype Ⅴ.The most economic and effective measure to control rice bacterial blight is to breed resistant cultivars for widely planting using resistance genes.The Institute of Plant Protection,Guangdong Academy of Agricultural Sciences,and Agricultural Science Research Institute of Panyu District of Guangzhou used IRBB5 carrying the recessive xa5 gene from IRRI that is resistant to pathotype Ⅴ to breed resistant varieties with rice blast resistance source,through hybridization,multiple cross,pedigree selection and synchronous resistance evaluation.We successfully bred series of new resistant rice varieties such as Baijiangzhan,Baijingzhan and Baisizhan,which showed resistance to strong virulence pathotype Ⅴ(grade 1-3)of bacterial blight and rice blast(mediate to high resistance),good grain quality(level 3 of rice quality of Guangdong),and yield equivalent to major cultivars(compared with region trial control cultivars of Guangdong).These new resistant varieties were promoted and planted in the strong virulence pathotype Ⅴ region along the west coast of Guangdong,which showed favorable superiority and wide application prospect in controlling rice bacterial blight with resistance varieties.展开更多
Diarrhea is among the leading causes of morbidity and mortality in children aged Escherichia coli (DEC) accounts for 30% - 40% of childhood diarrhea cases. To identify the pathotypes involved in diarrheal outbreaks in...Diarrhea is among the leading causes of morbidity and mortality in children aged Escherichia coli (DEC) accounts for 30% - 40% of childhood diarrhea cases. To identify the pathotypes involved in diarrheal outbreaks in Kenya, we analyzed archived E. coli isolates from children E. coli confirmation and antimicrobial susceptibility testing were done using the VITEK<sup>®</sup>2 instrument. Pathotype identification was performed via conventional polymerase chain reaction. Of 175 E. coli isolates, 48 (27%) were DEC pathotypes, with enteroaggregative E. coli (EAEC) predominating (71%, 34/48). Enterohemorrhagic (EHEC) and enteropathogenic E. coli (EPEC) represented 19% and 10% of isolates, respectively. Enteroinvasive and enterotoxigenic pathotypes were not identified. All DEC isolates were susceptible to amikacin, ertapenem, imipenem, meropenem and tigecycline. Conversely, most (>80%) isolates were resistant to ampicillin, ampicillin-sulbactam and sulfamethoxazole-trimethoprim. Half of all EAEC and EPEC strains were resistant to cefazolin while half of EHEC isolates were resistant to ciprofloxacin and moxifloxacin. In total, 18 resistance phenotypes were identified with “ampicillin-cefazolin-ampicillin/ sulbactam-sulfamethoxazole/trimethoprim” predominating (33%, 16/48). The majority (81%) of DEC isolates were multidrug-resistant, with extended-spectrum beta-lactamase production identified in 8% of these isolates. This study highlights the predominance of Enteroaggregative E. coli and multidrug resistance of DEC pathotypes. Studying the epidemiology of diarrheal disease and antimicrobial resistance surveillance, will aid in identifying dominant etiological agents of diarrhea and newly emerging resistant strains in informal settlements.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.32202463)China Agriculture Research System(Grant No.CARS-27)the Agricultural Science and Technology Innovation Program(Grant No.CAAS-ASTIP-2021-RIP-02)。
文摘Apple leaf spot,caused by the Alternaria alternata apple pathotype(AAAP),is an important fungal disease of apple.To understand the molecular basis of resistance and pathogenesis in apple leaf spot,the transcriptomes of two apple cultivars‘Hanfu'(HF)(resistant)and‘Golden Delicious'(GD)(susceptible)were analyzed at 0,6,18,24 and 48 h after AAAP inoculation by RNA-Seq.At each time point,a large number of significantly differentially expressed genes(DEGs)were screened between AAAP-inoculated and uninoculated apple leaves.Analysis of the common DEGs at four time points revealed significant differences in the resistance of‘HF'and‘GD'apple to AAAP infection.RLP,RNL,and JA signal-related genes were upregulated in both cultivars to restrict AAAP development.However,genes encoding CNLs,TNLs,WRKYs,and AP2s were only activated in‘HF'as part of the resistance response,of which,some play major roles in the regulation of ET and SA signal transduction.Further analysis showed that many DEGs with opposite expression trends in the two hosts may play important regulatory roles in response to AAAP infection.Transient expression of one such gene MdERF110 in‘GD'apple leaves improved AAAP resistance.Collectively,this study highlights the reasons for differential resistance to AAAP infection between‘HF'and‘GD'apples which can theoretically assist the molecular breeding of disease-resistant apple crops.
基金Special Fund of Agro-scientific Research in Public Interest(201303015)Earmarked Fund for China Agriculture Research System(CARS-01-24,2019KJ105)+1 种基金Science and Technology Planning Project of Guangdong Province(2015A020210081)Special Fund for Science and Technology Innovation Strategy of Guangdong Academy of Agricultural Sciences(R2016PY-JX005,R2016PY-QY009)。
文摘In recent years,the strong virulence pathotype Ⅴ of rice bacterial blight grew up quickly in Southern China,which has become a major population and spread to the rice regions of Jiangsu and Zhejiang provinces in Southern China.Since pathotype Ⅴ caused serious bacterial blight disease in rice production regions,it is urgent to breed and promote resistant varieties against pathotype Ⅴ.The most economic and effective measure to control rice bacterial blight is to breed resistant cultivars for widely planting using resistance genes.The Institute of Plant Protection,Guangdong Academy of Agricultural Sciences,and Agricultural Science Research Institute of Panyu District of Guangzhou used IRBB5 carrying the recessive xa5 gene from IRRI that is resistant to pathotype Ⅴ to breed resistant varieties with rice blast resistance source,through hybridization,multiple cross,pedigree selection and synchronous resistance evaluation.We successfully bred series of new resistant rice varieties such as Baijiangzhan,Baijingzhan and Baisizhan,which showed resistance to strong virulence pathotype Ⅴ(grade 1-3)of bacterial blight and rice blast(mediate to high resistance),good grain quality(level 3 of rice quality of Guangdong),and yield equivalent to major cultivars(compared with region trial control cultivars of Guangdong).These new resistant varieties were promoted and planted in the strong virulence pathotype Ⅴ region along the west coast of Guangdong,which showed favorable superiority and wide application prospect in controlling rice bacterial blight with resistance varieties.
文摘Diarrhea is among the leading causes of morbidity and mortality in children aged Escherichia coli (DEC) accounts for 30% - 40% of childhood diarrhea cases. To identify the pathotypes involved in diarrheal outbreaks in Kenya, we analyzed archived E. coli isolates from children E. coli confirmation and antimicrobial susceptibility testing were done using the VITEK<sup>®</sup>2 instrument. Pathotype identification was performed via conventional polymerase chain reaction. Of 175 E. coli isolates, 48 (27%) were DEC pathotypes, with enteroaggregative E. coli (EAEC) predominating (71%, 34/48). Enterohemorrhagic (EHEC) and enteropathogenic E. coli (EPEC) represented 19% and 10% of isolates, respectively. Enteroinvasive and enterotoxigenic pathotypes were not identified. All DEC isolates were susceptible to amikacin, ertapenem, imipenem, meropenem and tigecycline. Conversely, most (>80%) isolates were resistant to ampicillin, ampicillin-sulbactam and sulfamethoxazole-trimethoprim. Half of all EAEC and EPEC strains were resistant to cefazolin while half of EHEC isolates were resistant to ciprofloxacin and moxifloxacin. In total, 18 resistance phenotypes were identified with “ampicillin-cefazolin-ampicillin/ sulbactam-sulfamethoxazole/trimethoprim” predominating (33%, 16/48). The majority (81%) of DEC isolates were multidrug-resistant, with extended-spectrum beta-lactamase production identified in 8% of these isolates. This study highlights the predominance of Enteroaggregative E. coli and multidrug resistance of DEC pathotypes. Studying the epidemiology of diarrheal disease and antimicrobial resistance surveillance, will aid in identifying dominant etiological agents of diarrhea and newly emerging resistant strains in informal settlements.
