Citrus huanglongbing（HLB） has become a major disease and limiting factor of production in citrus areas that have become infected. The destruction to the affected citrus industries has resulted in a tremendous increa...Citrus huanglongbing（HLB） has become a major disease and limiting factor of production in citrus areas that have become infected. The destruction to the affected citrus industries has resulted in a tremendous increase to support research that in return has resulted in significant information on both applied and basic knowledge concerning this important disease to the global citrus industry. Recent research indicates the relationship between citrus and the causal agent of HLB is shaped by multiple elements, in which host defense responses may also play an important role. This review is intended to provide an overview of the importance of HLB to a wider audience of plant biologists. Recent advances on host-pathogen interactions, population genetics and vectoring of the causal agent are discussed.展开更多
Objective To study the chemical constituents from Pericarpium Citri Reticulatae （Citrus reticulata）. Methods The chemical constituents were isolated and purified by silica gel column, Sephadex LH-20, and ODS column ...Objective To study the chemical constituents from Pericarpium Citri Reticulatae （Citrus reticulata）. Methods The chemical constituents were isolated and purified by silica gel column, Sephadex LH-20, and ODS column chromatography. The structures were identified by spectral data. Results Nineteen compounds were isolated and identified as 4＇,5,6,7-tetramethoxyflavone （1）, 3,3＇,4＇,5,6,7,8-heptmethoxyflavone （2）, sinensetin （3）, 5-O-demethylnobiletin （4）, tangeretin （5）, nobiletin （6）, apigenin （7）, 5-O- desmethyltangeretin （8）, 5,7-dihydroxy-3,3＇,4＇,6-tetramethoxyflavone （9）, pachypodol （10）, 4＇,5,6,7-tetramethoxyflavanone （11）, 3＇,4＇,5,7,8-pentamethoxyflavanone （12）, agestricin C （13）, scoparone （14）, isoscopoletin （15）, hesperidin （16）, didymin （17）, methylhesperidine （18）, and naringin （19）. Conclusion Compounds 9-15 are obtained from this plant for the first time.展开更多
Diaporthe species are important pathogens of a wide range of hosts including many economically important crops.Diaporthe citri is generally accepted to cause melanose of Citrus fruits,leaves and shoots;stem-end rot of...Diaporthe species are important pathogens of a wide range of hosts including many economically important crops.Diaporthe citri is generally accepted to cause melanose of Citrus fruits,leaves and shoots;stem-end rot of fruits and gummosis of perennial branches.In this study,147 strains of Diaporthe were isolated from diseased leaves,twigs,fruits and branches of Citrus from Shaanxi,Zhejiang,Guangxi,Fujian,Guangdong,Jiangxi,Hunan,Chongqing and Shanghai and identified by morphology and molecular analysis of nuclear ribosomal internal transcribed spacer(ITS),partial sequences of translation elongation factor 1-α(EF 1-α),tubulin(TUB)and calmodulin(CAL)genes.All strains from Citrus clustered in three clades.Diaporthe citri was the predominant species and is compared with strains from Florida,USA,where this species was first collected and described.Two new taxa differing from D.citri are described as D.citriasiana and D.citrichinensis in this paper.Inoculation tests indicate that all three species are able to cause stem-end rot of fruits,while only D.citri could cause melanose on leaves.展开更多
Amyloid-beta-induced neuronal cell death contributes to cognitive decline in Alzheimer’s disease.Citri Reticulatae Semen has diverse beneficial effects on neurodegenerative diseases,including Parkinson’s and Hunting...Amyloid-beta-induced neuronal cell death contributes to cognitive decline in Alzheimer’s disease.Citri Reticulatae Semen has diverse beneficial effects on neurodegenerative diseases,including Parkinson’s and Huntington’s diseases,however,the effect of Citri Reticulatae Semen on Alzheimer’s disease remains unelucidated.In the current study,the anti-apoptotic and autophagic roles of Citri Reticulatae Semen extract on amyloid-beta-induced apoptosis in PC12 cells were first investigated.Citri Reticulatae Semen extract protected PC12 cells from amyloid-beta-induced apoptosis by attenuating the Bax/Bcl-2 ratio via activation of autophagy.In addition,Citri Reticulatae Semen extract was confirmed to bind amyloid-beta as revealed by biolayer interferometry in vitro,and suppress amyloid-beta-induced pathology such as paralysis,in a transgenic Caenorhabditis elegans in vivo model.Moreover,genetically defective Caenorhabditis elegans further confirmed that the neuroprotective effect of Citri Reticulatae Semen extract was autophagy-dependent.Most importantly,Citri Reticulatae Semen extract was confirmed to improve cognitive impairment,neuronal injury and amyloid-beta burden in 3×Tg Alzheimer’s disease mice.As revealed by both in vitro and in vivo models,these results suggest that Citri Reticulatae Semen extract is a potential natural therapeutic agent for Alzheimer’s disease via its neuroprotective autophagic effects.展开更多
柑橘链格孢褐斑病(Alternaria brown spot,ABS)是新近在我国局部地区新发现的病害,主要为害宽皮柑橘及某些杂交种柑橘,引起落叶、落果和枯梢,不仅影响产量,还影响果实的销售,造成严重损失,并且病害呈逐渐扩散和加重的趋势。药剂防治是...柑橘链格孢褐斑病(Alternaria brown spot,ABS)是新近在我国局部地区新发现的病害,主要为害宽皮柑橘及某些杂交种柑橘,引起落叶、落果和枯梢,不仅影响产量,还影响果实的销售,造成严重损失,并且病害呈逐渐扩散和加重的趋势。药剂防治是目前防治ABS的最有效措施,然而目前尚无药剂被登记用于该病害的防治。本研究以来自我国各褐斑病发生区的54个代表菌株构成一个群体,应用刃天青(resazurin,RZ)显色法测定病菌群体对新烟酰胺类杀菌剂啶酰菌胺、氟酰胺和噻氟酰胺,以及吡啶类杀菌剂氟啶胺的敏感性。结果表明,该病菌种群孢子萌发对啶酰菌胺、氟酰胺、噻氟酰胺和氟啶胺而言都是野生的敏感群体,尚未发现抗药性菌株,平均EC50值分别为0.467 7μg/mL、0.010 3μg/mL、0.061 9μg/mL和0.010 0μg/mL。广东和浙江菌株对啶酰菌胺较不敏感,重庆菌株对噻氟酰胺更敏感,而对氟酰胺和氟啶胺的敏感性则与菌株的地理来源无关。柑橘褐斑病菌种群对这4种杀菌剂敏感性的确定,可为选择药剂防治ABS提供依据,并为这些药剂推广后的抗药性监测提供基础研究。展开更多
[Objectives] This study aimed to establish HPLC fingerprint and conduct cluster analysis and principle component analysis for Citri Reticulatae Pericarpium Viride. [Methods] Using the HPLC method, the determination wa...[Objectives] This study aimed to establish HPLC fingerprint and conduct cluster analysis and principle component analysis for Citri Reticulatae Pericarpium Viride. [Methods] Using the HPLC method, the determination was performed on XSelect~® HSS T3-C_(18) column with mobile phase of acetonitrile-0.5% acetic acid solution(gradient elution) at the flow rate of 1.0 mL/min. The detection wavelength was 360 nm. The column temperature was 25℃. The sample size was 10 μL. With peak of hesperidin as the reference, HPLC fingerprints of 10 batches of Citri Reticulatae Pericarpium Viride were determined. The similarity of the 10 batches of samples was evaluated by Similarity Evaluation System for Chromatographic Fingerprint of TCM(2012 edition) to determine the common peaks. Cluster analysis and principal component analysis were performed by using SPSS 17.0 statistical software. [Results] The HPLC fingerprints of the 10 batches of medicinal materials had total 11 common peaks, and the similarity was 0.919-1.000, indicating that the chemical composition of the 10 batches of medicinal materials was consistent. There were 11 common components in the 10 batches of medicinal materials, but their contents were different. When the Euclidean distance was 20, the 10 batches of samples were divided into two categories, S4 in the first category, and the others in the second one. When the Euclidean distance was 5, the second category could be further divided into two sub-categories, S1 and S10 in one sub-category, and S2, S3, S5, S6, S7, S8 and S9 in the other one. The principle component analysis showed that cumulative contribution rate of the two main component factors was 92.797%, and the comprehensive score of S7 was the highest with the best quality. [Conclusions] The results of HPLC fingerprinting, cluster analysis and principle component analysis can provide reference for the quality control of Citri Reticulatae Pericarpium Viride.展开更多
Insecticide resistance in Panonychus citri is a major obstacle to mite control in citrus orchards.Pyrethroid insecticides are continually used to control mites in China,although resistance to pyrethroids has evolved i...Insecticide resistance in Panonychus citri is a major obstacle to mite control in citrus orchards.Pyrethroid insecticides are continually used to control mites in China,although resistance to pyrethroids has evolved in some populations.Here,the resistance to the pyrethroid fenpropathrin was investigated and 7 out of 8 field-collected populations of P citri exhibited a high level of resistance,ranging from 171-fold to 15391-fold higher than the susceptible(SS)comparison strain.Three voltage-gated sodium channel(VGSC)mutations were identified in the tested populations:L1031V,F1747L,and F17511.Amplicon sequencing was used to evaluate the frequency of these mutations in the 19 field populations.L1031V and F1751I were present in all populations at frequencies of 11.6%-82.1%and 0.5%-31.8%,respectively,whereas the F1747L mutation was only present in 12 populations from Chongqing,Sichuan,Guangxi,and Yunnan provinces.Introduction of these mutations singly or in combination into transgenic flies significantly increased their resistance to fenpropathrin and these flies also exhibited reduced mortality after exposure to the pyrethroids permethrin andβ-cypermethrin.Panonychus citri VGSC homology modeling and ligand docking indicate that F1747 and F1751 form direct binding contacts with pyrethroids,which are lost with mutation,whereas L1031 mutation may diminish pyrethroid effects through an allosteric mechanism.Overall,the results provide molecular markers for monitoring pest resistance to pyrethroids and offer new insights into the basis of pyrethroid actions on sodium channels.展开更多
[Objectives]The paper was to investigate the development of Panonychus citri resistance to commonly used pesticides in major citrus producing areas in China,and to screen out new green and efficient agents for its con...[Objectives]The paper was to investigate the development of Panonychus citri resistance to commonly used pesticides in major citrus producing areas in China,and to screen out new green and efficient agents for its control and prevention.[Methods]The resistance changes of field populations of P.citri to abamectin,pyridaben,and bifenazate in 12 locations across five provinces in China were compared using the leaf disc impregnation method.[Results]P.citri in the tested areas exhibited the most severe resistance to abamectin,with approximately 91.7%of the field populations showing high levels of resistance to abamectin(112.1-560.5 times);50%of P.citri populations exhibited high levels of resistance to pyridaben(123.0-202.7 times),while the remaining populations showed intermediate levels of resistance(25.6-80.3 times);except for the Zhejiang Xiangshan 2019 and Jiangxi Yudu 2019 populations,which exhibited a medium level of resistance to bifenazate,the remaining 10 monitored populations demonstrated a high level of resistance to bifenazate(140.4-686.1 times).[Conclusions]It is advisable to discontinue the use of abamectin and bifenazate due to significant resistance observed in populations of P.citri monitored in 12 locations across 5 provinces.It is recommended to reduce the frequency of pyridaben use and alternate with other acaricides that have different mechanisms of action due to the varying degrees of resistance developed.展开更多
[Objectives]To investigate the mechanisms and pharmacologic effects of Citri Reticulatae Pericarpium against keloids by network pharmacology systematically.[Methods]TCMSP,Uniprot and BATMAN-TCM databases were used to ...[Objectives]To investigate the mechanisms and pharmacologic effects of Citri Reticulatae Pericarpium against keloids by network pharmacology systematically.[Methods]TCMSP,Uniprot and BATMAN-TCM databases were used to obtain the active constituents and targets of Citri Reticulatae Pericarpium."Keloid"was used as key word to search for related therapeutic targets from Drug Bank,OMIM,TTD,and GEO databases.The Chinese medicine compound-target network was constructed by Cytoscape software.Besides,gene ontology(GO)and Kyoto Encyclopedia of genes and genome enrichment analysis were also performed.Afterward,Discovery Studio software was used to assess the interaction of key components and genes.[Results]Five active components of Citri Reticulatae Pericarpium,773 compound targets and 676 keloid treatment targets were obtained in the databases.After the intersection,there are 47 targets of Citri Reticulatae Pericarpium for treating keloids.Hub genes were identified such as MMP9,IL6,TNF,TP53,and VEGFA,which were enriched in tumor necrosis factor-α,nuclear factor kappa-B,and other signaling pathways.The molecular docking stimulation confirmed the interaction between the MMP9 and three components of Citri Reticulatae Pericarpium.[Conclusions]Citri Reticulatae Pericarpium may play an important role in treating keloids through modulating genes and signaling pathways.The present study sheds light on the mechanisms of active compounds of Citri Reticulatae Pericarpium for the treatment of keloids.展开更多
Panonychus citriMcGregor(Acari:Tetranychidae),a destructive citrus pest,causes considerable annual economic losses due to its short lifespan and rapid resistancedevelopment.MicroRNA(miRNA)-induced RNA interference is ...Panonychus citriMcGregor(Acari:Tetranychidae),a destructive citrus pest,causes considerable annual economic losses due to its short lifespan and rapid resistancedevelopment.MicroRNA(miRNA)-induced RNA interference is a promising approachfor pest control because of endogenous regulation of pest growth and development.Tosearch for miRNAs with potential insecticidal activity inP.citri,genome-wide analysis ofmiRNAs at different developmental stages was conducted,resulting in the identificationof 136 miRNAs,including 73 known and 63 novel miRNAs.A total of 17 isomiRNAsand 12 duplicated miRNAs were characterized.MiR-1 and miR-252-5p were identified asreference miRNAs forP.citriandTetranychus urticae.Based on differential expressionanalysis,treatments with miR-let-7a and miR-315 mimics and the miR-let-7a antagomirsignificantly reduced the egg hatch rate and resulted in abnormal egg development.Over-expression or downregulation of miR-34-5p and miR-305-5p through feeding significantlydecreased the adult eclosion rate and caused molting defects.The 4 miRNAs,miR-let-7a,miR-315,miR-34-5p,and miR-305-5p,had important regulatory functions and insectici-dal properties in egg hatching and adult eclosion.In general,these data advance our un-derstanding of miRNAs in mite biology,which can assist future studies on insect-specificmiRNA-based green pest control technology.展开更多
Huanglongbing(HLB) is a devastating disease that has led to an acute crisis for growers of citrus, one of the world's most important fruit crops. The phloem-feeding Asian citrus psyllid(ACP), Diaphorina citri, is ...Huanglongbing(HLB) is a devastating disease that has led to an acute crisis for growers of citrus, one of the world's most important fruit crops. The phloem-feeding Asian citrus psyllid(ACP), Diaphorina citri, is the main pest at the new shoot stage and is the only natural vector of HLB pathogenic bacteria. Little is known about how plants perceive and defend themselves from this destructive pest. Here, we characterized changes in the expression of various genes in citrus plants that were continuously infested by D. citri for different durations(12, 24, and 48 h). A total of 5 219 differentially expressed genes(DEGs) and 643 common DEGs were identified across all time points. Several pathways related to defense were activated, such as peroxisome, alpha-linolenic acid metabolism, and phenylpropanoid and terpenoid biosynthesis, and some pathways related to growth and signal transduction were suppressed in response to D. citri infestation. The expression of genes including kinases(CML44, CIPK6, and XTH6), phytohormones(SAMT, LOX6, and NPR3), transcription factors(bHLH162, WRKY70, and WRKY40), and secondary metabolite synthesis-related genes(PAL, 4CL2, UGT74B1 and CYP82G1) was significantly altered in response to D. citri infestation. The findings of this study greatly enhance our understanding of the mechanisms underlying the defense response of citrus plants to D. citri infestation at the molecular level. Functional characterization of the candidate defense-related genes identified in this study will aid the molecular breeding of insect-resistant citrus varieties.展开更多
The Asian citrus psyllid,Diaphorina citri Kuwayama,is among the most im-portant pests of citrus.It is the main vector of the Huanglongbing(HLB)pathogen Can-didatus Liberibacter asiaticus(CLas),which causes severe loss...The Asian citrus psyllid,Diaphorina citri Kuwayama,is among the most im-portant pests of citrus.It is the main vector of the Huanglongbing(HLB)pathogen Can-didatus Liberibacter asiaticus(CLas),which causes severe losses in citrus crops.Control of D.citri is therefore of paramount importance to reduce the spread of HLB.In this re-gard,using RNA interference(RNAi)to silence target genes is a useful strategy to control psyllids.In this study,using RNAi,we examined the biological functions of the V-ATPase subunit E(V-ATP-E)gene of D.citri,including its effect on acquisition of CLas.The amino acid sequence of V-ATP-E from D.citri had high homology with proteins from other insects.V-ATP-E was expressed at all D.citri life stages analyzed,and the expres-sion level in mature adults was higher than that of teneral adults.Silencing of V-ATP-E resulted in a significant increase in mortality,reduced body weight,and induced cell apop-tosis of the D.citri midgut.The reduced expression of V-ATP-E was indicated to inhibit CLas passing through the midgut and into the hemolymph,leading to a majority of CLas being confined to the midgut.In addition,double-stranded RNA of D.citri V-ATP-E was safe to non-target parasitic wasps.These results suggest that V-ATP-E is an effective RNAi target that can be used in D.citri control to block CLas infection.展开更多
基金the United States citrus industry and various funding agencies for their commitment and continued support for HLB research
文摘Citrus huanglongbing（HLB） has become a major disease and limiting factor of production in citrus areas that have become infected. The destruction to the affected citrus industries has resulted in a tremendous increase to support research that in return has resulted in significant information on both applied and basic knowledge concerning this important disease to the global citrus industry. Recent research indicates the relationship between citrus and the causal agent of HLB is shaped by multiple elements, in which host defense responses may also play an important role. This review is intended to provide an overview of the importance of HLB to a wider audience of plant biologists. Recent advances on host-pathogen interactions, population genetics and vectoring of the causal agent are discussed.
基金Project of Guangdong Natural Science Foundation(No.2015A030310284,No.2015A030312001)Project of Chinese Public Welfare Industry Special(Agriculture)Research(No.201503142-03)Project of Agricultural Research in Guangdong Province(No.2015A020209065)
文摘Objective To study the chemical constituents from Pericarpium Citri Reticulatae （Citrus reticulata）. Methods The chemical constituents were isolated and purified by silica gel column, Sephadex LH-20, and ODS column chromatography. The structures were identified by spectral data. Results Nineteen compounds were isolated and identified as 4＇,5,6,7-tetramethoxyflavone （1）, 3,3＇,4＇,5,6,7,8-heptmethoxyflavone （2）, sinensetin （3）, 5-O-demethylnobiletin （4）, tangeretin （5）, nobiletin （6）, apigenin （7）, 5-O- desmethyltangeretin （8）, 5,7-dihydroxy-3,3＇,4＇,6-tetramethoxyflavone （9）, pachypodol （10）, 4＇,5,6,7-tetramethoxyflavanone （11）, 3＇,4＇,5,7,8-pentamethoxyflavanone （12）, agestricin C （13）, scoparone （14）, isoscopoletin （15）, hesperidin （16）, didymin （17）, methylhesperidine （18）, and naringin （19）. Conclusion Compounds 9-15 are obtained from this plant for the first time.
基金supported by China Agriculture Research System(CARS-27)Research Programs for Nonprofit Technology and Application of Zhejiang Province,China(2009CB119203)。
文摘Diaporthe species are important pathogens of a wide range of hosts including many economically important crops.Diaporthe citri is generally accepted to cause melanose of Citrus fruits,leaves and shoots;stem-end rot of fruits and gummosis of perennial branches.In this study,147 strains of Diaporthe were isolated from diseased leaves,twigs,fruits and branches of Citrus from Shaanxi,Zhejiang,Guangxi,Fujian,Guangdong,Jiangxi,Hunan,Chongqing and Shanghai and identified by morphology and molecular analysis of nuclear ribosomal internal transcribed spacer(ITS),partial sequences of translation elongation factor 1-α(EF 1-α),tubulin(TUB)and calmodulin(CAL)genes.All strains from Citrus clustered in three clades.Diaporthe citri was the predominant species and is compared with strains from Florida,USA,where this species was first collected and described.Two new taxa differing from D.citri are described as D.citriasiana and D.citrichinensis in this paper.Inoculation tests indicate that all three species are able to cause stem-end rot of fruits,while only D.citri could cause melanose on leaves.
基金supported by FDCT grants from the Macao Science and Technology Development Fund,China,No.002/2023/ALC(to BYKL)Foshan Medicine Dengfeng Project of China 2019-2021(to BYKL)+3 种基金the Science and Technology Program of Sichuan Province,Nos.2022YFS0620(to DQ)and MZGC20230041(to XFW)the TCMs Commission of Sichuan Province,No.2021MS469(to YT)the Science and Technology Program of Luzhou,No.2022-WGR-194(to YT)the Southwest Medical University Science and Technology Program,No.2021NJXNYD04(to DQ).
文摘Amyloid-beta-induced neuronal cell death contributes to cognitive decline in Alzheimer’s disease.Citri Reticulatae Semen has diverse beneficial effects on neurodegenerative diseases,including Parkinson’s and Huntington’s diseases,however,the effect of Citri Reticulatae Semen on Alzheimer’s disease remains unelucidated.In the current study,the anti-apoptotic and autophagic roles of Citri Reticulatae Semen extract on amyloid-beta-induced apoptosis in PC12 cells were first investigated.Citri Reticulatae Semen extract protected PC12 cells from amyloid-beta-induced apoptosis by attenuating the Bax/Bcl-2 ratio via activation of autophagy.In addition,Citri Reticulatae Semen extract was confirmed to bind amyloid-beta as revealed by biolayer interferometry in vitro,and suppress amyloid-beta-induced pathology such as paralysis,in a transgenic Caenorhabditis elegans in vivo model.Moreover,genetically defective Caenorhabditis elegans further confirmed that the neuroprotective effect of Citri Reticulatae Semen extract was autophagy-dependent.Most importantly,Citri Reticulatae Semen extract was confirmed to improve cognitive impairment,neuronal injury and amyloid-beta burden in 3×Tg Alzheimer’s disease mice.As revealed by both in vitro and in vivo models,these results suggest that Citri Reticulatae Semen extract is a potential natural therapeutic agent for Alzheimer’s disease via its neuroprotective autophagic effects.
基金Supported by National Natural Science Foundation of China(81603251)Key Research and Development Plan of Shanxi Province(201603D3113021)Project of Collaborative Innovation Center for the Comprehensive Development and Utilization of Medicinal Herbs in Shanxi Province(2017-JYXT-05)
文摘[Objectives] This study aimed to establish HPLC fingerprint and conduct cluster analysis and principle component analysis for Citri Reticulatae Pericarpium Viride. [Methods] Using the HPLC method, the determination was performed on XSelect~® HSS T3-C_(18) column with mobile phase of acetonitrile-0.5% acetic acid solution(gradient elution) at the flow rate of 1.0 mL/min. The detection wavelength was 360 nm. The column temperature was 25℃. The sample size was 10 μL. With peak of hesperidin as the reference, HPLC fingerprints of 10 batches of Citri Reticulatae Pericarpium Viride were determined. The similarity of the 10 batches of samples was evaluated by Similarity Evaluation System for Chromatographic Fingerprint of TCM(2012 edition) to determine the common peaks. Cluster analysis and principal component analysis were performed by using SPSS 17.0 statistical software. [Results] The HPLC fingerprints of the 10 batches of medicinal materials had total 11 common peaks, and the similarity was 0.919-1.000, indicating that the chemical composition of the 10 batches of medicinal materials was consistent. There were 11 common components in the 10 batches of medicinal materials, but their contents were different. When the Euclidean distance was 20, the 10 batches of samples were divided into two categories, S4 in the first category, and the others in the second one. When the Euclidean distance was 5, the second category could be further divided into two sub-categories, S1 and S10 in one sub-category, and S2, S3, S5, S6, S7, S8 and S9 in the other one. The principle component analysis showed that cumulative contribution rate of the two main component factors was 92.797%, and the comprehensive score of S7 was the highest with the best quality. [Conclusions] The results of HPLC fingerprinting, cluster analysis and principle component analysis can provide reference for the quality control of Citri Reticulatae Pericarpium Viride.
基金supported by the Science and Technology Basic Resources Investigation Program of China(2018FY101105)the National Natural Science Foundation of China(31972272,31871969)+1 种基金the Fundamental Research Funds for the Central Universities(SWU-XDPY22001)of Chinathe China Agricultural Research System of MOA and MARA.
文摘Insecticide resistance in Panonychus citri is a major obstacle to mite control in citrus orchards.Pyrethroid insecticides are continually used to control mites in China,although resistance to pyrethroids has evolved in some populations.Here,the resistance to the pyrethroid fenpropathrin was investigated and 7 out of 8 field-collected populations of P citri exhibited a high level of resistance,ranging from 171-fold to 15391-fold higher than the susceptible(SS)comparison strain.Three voltage-gated sodium channel(VGSC)mutations were identified in the tested populations:L1031V,F1747L,and F17511.Amplicon sequencing was used to evaluate the frequency of these mutations in the 19 field populations.L1031V and F1751I were present in all populations at frequencies of 11.6%-82.1%and 0.5%-31.8%,respectively,whereas the F1747L mutation was only present in 12 populations from Chongqing,Sichuan,Guangxi,and Yunnan provinces.Introduction of these mutations singly or in combination into transgenic flies significantly increased their resistance to fenpropathrin and these flies also exhibited reduced mortality after exposure to the pyrethroids permethrin andβ-cypermethrin.Panonychus citri VGSC homology modeling and ligand docking indicate that F1747 and F1751 form direct binding contacts with pyrethroids,which are lost with mutation,whereas L1031 mutation may diminish pyrethroid effects through an allosteric mechanism.Overall,the results provide molecular markers for monitoring pest resistance to pyrethroids and offer new insights into the basis of pyrethroid actions on sodium channels.
基金Guangxi Agricultural Science and Technology Self-financing Project(Z2022128)Fund Project of Guangxi Citrus Breeding and Cultivation Engineering Technology Research Center(2022A003).
文摘[Objectives]The paper was to investigate the development of Panonychus citri resistance to commonly used pesticides in major citrus producing areas in China,and to screen out new green and efficient agents for its control and prevention.[Methods]The resistance changes of field populations of P.citri to abamectin,pyridaben,and bifenazate in 12 locations across five provinces in China were compared using the leaf disc impregnation method.[Results]P.citri in the tested areas exhibited the most severe resistance to abamectin,with approximately 91.7%of the field populations showing high levels of resistance to abamectin(112.1-560.5 times);50%of P.citri populations exhibited high levels of resistance to pyridaben(123.0-202.7 times),while the remaining populations showed intermediate levels of resistance(25.6-80.3 times);except for the Zhejiang Xiangshan 2019 and Jiangxi Yudu 2019 populations,which exhibited a medium level of resistance to bifenazate,the remaining 10 monitored populations demonstrated a high level of resistance to bifenazate(140.4-686.1 times).[Conclusions]It is advisable to discontinue the use of abamectin and bifenazate due to significant resistance observed in populations of P.citri monitored in 12 locations across 5 provinces.It is recommended to reduce the frequency of pyridaben use and alternate with other acaricides that have different mechanisms of action due to the varying degrees of resistance developed.
基金Supported by Central Government Funds of Guiding Local Scientific and Technological Development for Sichuan Province(2021ZYD0057).
文摘[Objectives]To investigate the mechanisms and pharmacologic effects of Citri Reticulatae Pericarpium against keloids by network pharmacology systematically.[Methods]TCMSP,Uniprot and BATMAN-TCM databases were used to obtain the active constituents and targets of Citri Reticulatae Pericarpium."Keloid"was used as key word to search for related therapeutic targets from Drug Bank,OMIM,TTD,and GEO databases.The Chinese medicine compound-target network was constructed by Cytoscape software.Besides,gene ontology(GO)and Kyoto Encyclopedia of genes and genome enrichment analysis were also performed.Afterward,Discovery Studio software was used to assess the interaction of key components and genes.[Results]Five active components of Citri Reticulatae Pericarpium,773 compound targets and 676 keloid treatment targets were obtained in the databases.After the intersection,there are 47 targets of Citri Reticulatae Pericarpium for treating keloids.Hub genes were identified such as MMP9,IL6,TNF,TP53,and VEGFA,which were enriched in tumor necrosis factor-α,nuclear factor kappa-B,and other signaling pathways.The molecular docking stimulation confirmed the interaction between the MMP9 and three components of Citri Reticulatae Pericarpium.[Conclusions]Citri Reticulatae Pericarpium may play an important role in treating keloids through modulating genes and signaling pathways.The present study sheds light on the mechanisms of active compounds of Citri Reticulatae Pericarpium for the treatment of keloids.
基金supported by the National Natural Sci-ence Foundation of China(31972272,31871969)the Fundamental Research Funds for the Central Universi-ties(SWU-XDPY22001)of Chinathe China Agri-cultural Research System of MOA and MARA。
文摘Panonychus citriMcGregor(Acari:Tetranychidae),a destructive citrus pest,causes considerable annual economic losses due to its short lifespan and rapid resistancedevelopment.MicroRNA(miRNA)-induced RNA interference is a promising approachfor pest control because of endogenous regulation of pest growth and development.Tosearch for miRNAs with potential insecticidal activity inP.citri,genome-wide analysis ofmiRNAs at different developmental stages was conducted,resulting in the identificationof 136 miRNAs,including 73 known and 63 novel miRNAs.A total of 17 isomiRNAsand 12 duplicated miRNAs were characterized.MiR-1 and miR-252-5p were identified asreference miRNAs forP.citriandTetranychus urticae.Based on differential expressionanalysis,treatments with miR-let-7a and miR-315 mimics and the miR-let-7a antagomirsignificantly reduced the egg hatch rate and resulted in abnormal egg development.Over-expression or downregulation of miR-34-5p and miR-305-5p through feeding significantlydecreased the adult eclosion rate and caused molting defects.The 4 miRNAs,miR-let-7a,miR-315,miR-34-5p,and miR-305-5p,had important regulatory functions and insectici-dal properties in egg hatching and adult eclosion.In general,these data advance our un-derstanding of miRNAs in mite biology,which can assist future studies on insect-specificmiRNA-based green pest control technology.
基金supported by Key Realm R&D Program of Guangdong Province (Grant No. 2020B0202090005)Special Fund for Scientific Innovation Strategy-construction of High Level Academy of Agriculture Science (Grant No. R2020PY-JG002)the President Foundation of Guangdong Academy of Agricultural Sciences (Grant No. 202030)。
文摘Huanglongbing(HLB) is a devastating disease that has led to an acute crisis for growers of citrus, one of the world's most important fruit crops. The phloem-feeding Asian citrus psyllid(ACP), Diaphorina citri, is the main pest at the new shoot stage and is the only natural vector of HLB pathogenic bacteria. Little is known about how plants perceive and defend themselves from this destructive pest. Here, we characterized changes in the expression of various genes in citrus plants that were continuously infested by D. citri for different durations(12, 24, and 48 h). A total of 5 219 differentially expressed genes(DEGs) and 643 common DEGs were identified across all time points. Several pathways related to defense were activated, such as peroxisome, alpha-linolenic acid metabolism, and phenylpropanoid and terpenoid biosynthesis, and some pathways related to growth and signal transduction were suppressed in response to D. citri infestation. The expression of genes including kinases(CML44, CIPK6, and XTH6), phytohormones(SAMT, LOX6, and NPR3), transcription factors(bHLH162, WRKY70, and WRKY40), and secondary metabolite synthesis-related genes(PAL, 4CL2, UGT74B1 and CYP82G1) was significantly altered in response to D. citri infestation. The findings of this study greatly enhance our understanding of the mechanisms underlying the defense response of citrus plants to D. citri infestation at the molecular level. Functional characterization of the candidate defense-related genes identified in this study will aid the molecular breeding of insect-resistant citrus varieties.
基金supported by the National Joint Fund for Regional Innovation and Development(U22A20481)the Laboratory of Lingnan Modern Agriculture Project(NT2021003)the National High-Level Talent Special Support Plan(2020)to BLQ and China Postdoctoral Science Foundation(No.2022M711208)to CFG。
文摘The Asian citrus psyllid,Diaphorina citri Kuwayama,is among the most im-portant pests of citrus.It is the main vector of the Huanglongbing(HLB)pathogen Can-didatus Liberibacter asiaticus(CLas),which causes severe losses in citrus crops.Control of D.citri is therefore of paramount importance to reduce the spread of HLB.In this re-gard,using RNA interference(RNAi)to silence target genes is a useful strategy to control psyllids.In this study,using RNAi,we examined the biological functions of the V-ATPase subunit E(V-ATP-E)gene of D.citri,including its effect on acquisition of CLas.The amino acid sequence of V-ATP-E from D.citri had high homology with proteins from other insects.V-ATP-E was expressed at all D.citri life stages analyzed,and the expres-sion level in mature adults was higher than that of teneral adults.Silencing of V-ATP-E resulted in a significant increase in mortality,reduced body weight,and induced cell apop-tosis of the D.citri midgut.The reduced expression of V-ATP-E was indicated to inhibit CLas passing through the midgut and into the hemolymph,leading to a majority of CLas being confined to the midgut.In addition,double-stranded RNA of D.citri V-ATP-E was safe to non-target parasitic wasps.These results suggest that V-ATP-E is an effective RNAi target that can be used in D.citri control to block CLas infection.
