[Objectives]This study was conducted to develop a rapid identification method for citrus germline materials resistant to Huanglongbing disease and lay a basis for accelerating citrus breeding for resistance to Huanglo...[Objectives]This study was conducted to develop a rapid identification method for citrus germline materials resistant to Huanglongbing disease and lay a basis for accelerating citrus breeding for resistance to Huanglongbing and increasing the breeding efficiency.[Methods]Thirty-six citrus germplasms suspected to be resistant to citrus Huanglongbing disease were collected.The method of direct high grafting to citrus trees infected with Huanglongbing pathogen was adopted.The resistance of the test materials was identified and evaluated by field symptoms combined with quantitative PCR.It was defined as the top grafting identification method.[Results]The test materials that were grafted in spring started to germinate after one month,and three months late(June 5,2018)typical mottled yellowing on leaves was observed on KH-14 for the first time.After four months(July 5,2018)of top grafting,typical mottled yellowing occurred on 23 materials,and 11 materials showed no such symptom.After six months(September 4,2018)of top grafting,although the growth of KH-18,KH-12,KHY-4,KHY-5 and KHY-6 were normal,yellowing was observed on their leaves.Only KH-21 grew well,and showed no yellow shoots and yellowing leaves.It was identified as the material with resistance to Huanglongbing disease.Quantitative PCR tests on the above six materials showed that KH-21 was negative and other five were positive.Real-time fluorescence quantitative PCR test indicated that the average Huanglongbing bacteria amount in KH-21 was 1870.0 cell/μg DNA,and the average Huanglongbing bacteria amount in the control material was 372285.5 cell/μg DNA,indicating KH-21 was resistant to Huanglongbing bacteria.[Conclusions]The method for infecting bacteria by top grafting takes six months,can detect large amount of seedlings,and is time-saving,efficient,cost-saving and accurate.This method can quickly identify the resistance of citrus varieties to citrus Huanglongbing disease,and can be popularized and used in the identification of citrus Huanglongbing disease resistance.展开更多
In order to further promote the prevention and control research of Panonychus citri and improve its control effect,this paper summarizes the main influencing factors of the outbreak,main control technology and drug re...In order to further promote the prevention and control research of Panonychus citri and improve its control effect,this paper summarizes the main influencing factors of the outbreak,main control technology and drug resistance of P.citri,and puts forward the research focus and control strategy.展开更多
Tetranychus urticae Koch;Insecticide resistance;Chemical control This paper elaborates the occurrence factors and damage characteristics of Tetranychus urticae Koch in China,and emphatically summarizes three main cont...Tetranychus urticae Koch;Insecticide resistance;Chemical control This paper elaborates the occurrence factors and damage characteristics of Tetranychus urticae Koch in China,and emphatically summarizes three main control strategies of T.urticae,namely agricultural control,chemical control and biological control,as well as research progress in its resistance mechanisms.The problems existing in controlling T.urticae and its resistance management strategies are put forward,to provide a theoretical basis for the resistance management and comprehensive control of T.urticae.展开更多
The 40S ribosomal protein SA(RPSA)functions as an important regulatory factor in plant resistance to abiotic stresses.However,the role of RPSA in response to plant virus infection is poorly understood.Citrus yellow ve...The 40S ribosomal protein SA(RPSA)functions as an important regulatory factor in plant resistance to abiotic stresses.However,the role of RPSA in response to plant virus infection is poorly understood.Citrus yellow vein clearing virus(CYVCV)has a significantly negative impact on citrus production,and its coat protein(CP)is involved in viral pathogenicity.In this study,we revealed the interaction of CP with Eureka lemon 40S RPSA(ClRPSA-2)in the nucleus,membrane,and endoplasmic reticulum of Nicotiana benthamiana.Further experiments demonstrated that the ClRPSA-2 N-terminal conserved region(amino acids 22—122)was involved in the interaction with CP,and the ClRPSA-2 expression in young Eureka lemon leaves significantly reduced.Transient expression of ClRPSA-2 triggered the expression of jasmonic acid(JA),photosynthetic pathway-and resistance-related genes,as well as increased the JA content and maximum photochemical efficiency(Fv/Fm)in lemon.Furthermore,ClRPSA-2 negatively regulated CYVCV resistance in plants,which induced resistance to other citrus viruses.These findings enhance our understanding of the interaction between CYVCV and citrus plants and provide a basis for future research on resistance breeding of citrus.展开更多
Citrus Huanglongbing(HLB)is one of the most devastating diseases in the citrus industry and is caused primarily by‘Candidatus Liberibacter asiaticus’(CLas),a phloem-restricted gram-negative bacterium transmitted via...Citrus Huanglongbing(HLB)is one of the most devastating diseases in the citrus industry and is caused primarily by‘Candidatus Liberibacter asiaticus’(CLas),a phloem-restricted gram-negative bacterium transmitted via citrus psyllids in the field.Precise CLas detection is crucial for HLB control,particularly during extensive surveys in new emerging regions.Unfortunately,the lack of a practical on-site detection method for CLas due to the limited specificity of immunostrips and the costive non-user friendliness approaches prevent the effective disease control.In this study,a probe-based recombinase polymerase amplification(RPA)targeting the CLas five-copy nrdB gene(β-subunit of ribonucleotide reductase,RNR)was developed and evaluated for its specificity,sensitivity,and reliability.To enhance user-friendliness and facilitate widely use,an All-in-one kit was premade as freeze-dried pellets in individual tubes,containing all necessary components except DNA template.The applicability of the All-in-one kit for CLas detection was confirmed using plant or psyllid crude DNA extracts.Collectively,the All-in-one kit offers a specific,sensitive,rapid,cost-effective,and practical alternative for diagnosing CLas in field conditions when coupled with simplified crude DNA extraction method,providing an alternative approach for on-site CLas detection in the context of HLB.展开更多
基金Guangxi Science and Technology Major Project(GK AA18118046-6GK AA18118046-4)+2 种基金National Key R&D Program of China(2019YFD1001402-HX01)Guangxi Science and Technology Base and Talent Project(GK AD16380046)Guangxi Innovation Team Citrus Chief Expert Post Project of National Modern Agriculture Industrial Technology System(nycytxgxcxtd-05-01)。
文摘[Objectives]This study was conducted to develop a rapid identification method for citrus germline materials resistant to Huanglongbing disease and lay a basis for accelerating citrus breeding for resistance to Huanglongbing and increasing the breeding efficiency.[Methods]Thirty-six citrus germplasms suspected to be resistant to citrus Huanglongbing disease were collected.The method of direct high grafting to citrus trees infected with Huanglongbing pathogen was adopted.The resistance of the test materials was identified and evaluated by field symptoms combined with quantitative PCR.It was defined as the top grafting identification method.[Results]The test materials that were grafted in spring started to germinate after one month,and three months late(June 5,2018)typical mottled yellowing on leaves was observed on KH-14 for the first time.After four months(July 5,2018)of top grafting,typical mottled yellowing occurred on 23 materials,and 11 materials showed no such symptom.After six months(September 4,2018)of top grafting,although the growth of KH-18,KH-12,KHY-4,KHY-5 and KHY-6 were normal,yellowing was observed on their leaves.Only KH-21 grew well,and showed no yellow shoots and yellowing leaves.It was identified as the material with resistance to Huanglongbing disease.Quantitative PCR tests on the above six materials showed that KH-21 was negative and other five were positive.Real-time fluorescence quantitative PCR test indicated that the average Huanglongbing bacteria amount in KH-21 was 1870.0 cell/μg DNA,and the average Huanglongbing bacteria amount in the control material was 372285.5 cell/μg DNA,indicating KH-21 was resistant to Huanglongbing bacteria.[Conclusions]The method for infecting bacteria by top grafting takes six months,can detect large amount of seedlings,and is time-saving,efficient,cost-saving and accurate.This method can quickly identify the resistance of citrus varieties to citrus Huanglongbing disease,and can be popularized and used in the identification of citrus Huanglongbing disease resistance.
基金Supported by Guangxi Agricultural Science and Technology Self-financing Project(Z2022128)Fund Project of Guangxi Citrus Breeding and Cultivation Engineering Technology Research Center(2023A001).
文摘In order to further promote the prevention and control research of Panonychus citri and improve its control effect,this paper summarizes the main influencing factors of the outbreak,main control technology and drug resistance of P.citri,and puts forward the research focus and control strategy.
基金Supported by Guangxi Agricultural Science and Technology Self-financing Project(Z2022128)Fund Project of Guangxi Citrus Breeding and Cultivation Engineering Technology Research Center(2023A001).
文摘Tetranychus urticae Koch;Insecticide resistance;Chemical control This paper elaborates the occurrence factors and damage characteristics of Tetranychus urticae Koch in China,and emphatically summarizes three main control strategies of T.urticae,namely agricultural control,chemical control and biological control,as well as research progress in its resistance mechanisms.The problems existing in controlling T.urticae and its resistance management strategies are put forward,to provide a theoretical basis for the resistance management and comprehensive control of T.urticae.
基金supported by Natural Science Foundation of Chongqing(CSTB2024NSCQ-MSX0311)Agricultural Technology Research and Development Service Program of Wanzhou District,and the Opening Project of Guangxi Key Laboratory of Germplasm Innovation and Utilization of Specialty Commercial Crops in North Guangxi(GASCKF202404).
文摘The 40S ribosomal protein SA(RPSA)functions as an important regulatory factor in plant resistance to abiotic stresses.However,the role of RPSA in response to plant virus infection is poorly understood.Citrus yellow vein clearing virus(CYVCV)has a significantly negative impact on citrus production,and its coat protein(CP)is involved in viral pathogenicity.In this study,we revealed the interaction of CP with Eureka lemon 40S RPSA(ClRPSA-2)in the nucleus,membrane,and endoplasmic reticulum of Nicotiana benthamiana.Further experiments demonstrated that the ClRPSA-2 N-terminal conserved region(amino acids 22—122)was involved in the interaction with CP,and the ClRPSA-2 expression in young Eureka lemon leaves significantly reduced.Transient expression of ClRPSA-2 triggered the expression of jasmonic acid(JA),photosynthetic pathway-and resistance-related genes,as well as increased the JA content and maximum photochemical efficiency(Fv/Fm)in lemon.Furthermore,ClRPSA-2 negatively regulated CYVCV resistance in plants,which induced resistance to other citrus viruses.These findings enhance our understanding of the interaction between CYVCV and citrus plants and provide a basis for future research on resistance breeding of citrus.
基金supported by the National Key R&D Program of China(2021YFD1400800)the Innovation Research 2035 Pilot Plan of Southwest University(SWU-XDZD22002)+2 种基金the Special Fund for Youth Team of Southwest University(SWU-XJLJ202310)the Natural Sciences Foundation of Chongqing,China(CSTB2024 NSCQ-MSX1133)the Southwest University Introduction of Talents Program(SWU120023).
文摘Citrus Huanglongbing(HLB)is one of the most devastating diseases in the citrus industry and is caused primarily by‘Candidatus Liberibacter asiaticus’(CLas),a phloem-restricted gram-negative bacterium transmitted via citrus psyllids in the field.Precise CLas detection is crucial for HLB control,particularly during extensive surveys in new emerging regions.Unfortunately,the lack of a practical on-site detection method for CLas due to the limited specificity of immunostrips and the costive non-user friendliness approaches prevent the effective disease control.In this study,a probe-based recombinase polymerase amplification(RPA)targeting the CLas five-copy nrdB gene(β-subunit of ribonucleotide reductase,RNR)was developed and evaluated for its specificity,sensitivity,and reliability.To enhance user-friendliness and facilitate widely use,an All-in-one kit was premade as freeze-dried pellets in individual tubes,containing all necessary components except DNA template.The applicability of the All-in-one kit for CLas detection was confirmed using plant or psyllid crude DNA extracts.Collectively,the All-in-one kit offers a specific,sensitive,rapid,cost-effective,and practical alternative for diagnosing CLas in field conditions when coupled with simplified crude DNA extraction method,providing an alternative approach for on-site CLas detection in the context of HLB.
