Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strateg...Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strategies to control the disease.As a soilborne pathogen,R.solanacearum naturally infects plants via roots.A huge limitation in studying plant-R.solanacearum interactions is the large variation of R.solanacearum infection assay due to the variable soil conditions and uneven inoculum exposure.Here,we developed a robust and reliable Petri-dish inoculation method which allows consistent and stable infection in young plant seedlings.This method is easy to use,takes about only 10 days from seed germination to the completion of inoculation assay,and requires less inoculum of bacteria as well as growth chamber space.We proved the efficacy of the seedling Petri-dish inoculation method by analyzing plant defense primed by molecular patterns,resistance of defense-related plant mutants,and virulence of R.solanacearum mutants.Furthermore,we demonstrated that the seedling Petri-dish inoculation method can be applied to other host plants such as tobacco and has great potential for high-throughput screening of resistant plant germplasms to bacterial wilt in the future.展开更多
To establish a standard system for geneticstudies on sheath blight resistance, a field testwas conducted at the experimental farm ofYangzhou University to compare several pro-cedures for inoculating rice plants with R...To establish a standard system for geneticstudies on sheath blight resistance, a field testwas conducted at the experimental farm ofYangzhou University to compare several pro-cedures for inoculating rice plants with R.solani Kuhn (RH9). The varieties used wereJasmine 85, Teqing (resistant or moderatelyresistant), and Lemont (susceptible). They展开更多
[Objectives]To find out the suitable inoculation method for Fusarium proliferatum.[Methods]Longmu 801 and TG4 were inoculated with rice grain-based inoculum at the bud and seedling stages and with root irrigation at t...[Objectives]To find out the suitable inoculation method for Fusarium proliferatum.[Methods]Longmu 801 and TG4 were inoculated with rice grain-based inoculum at the bud and seedling stages and with root irrigation at the seedling stage,respectively,and then,the plant height,aboveground biomass,underground biomass,incidence rate and disease index of the alfalfa were determined to conduct comprehensive resistance evaluation.[Results]There was obvious difference in disease resistance between the two alfalfa varieties.Among the three inoculation methods,the relative plant height,relative aboveground biomass and relative underground biomass of Longmu 801 differed insignificantly(P>0.05),all around 100.There were significant differences in TG4 among different inoculation methods(P<0.05).The incidence rates and disease indices of Longmu 801 and TG4 inoculated with rice grain-based inoculum at the bud stage were the highest,and their incidence rates and disease indices were 73.3%and 100%,and 40 and 60,respectively,significantly higher than those under the other two inoculation methods.The incidence rates and disease indices of Longmu 801 and TG4 inoculated with rice grain-based inoculum at the seedling stage were the lowest,and their incidence rates and disease indices were 0%and 13.30%,and 0 and 5.33,respectively,significantly lower than those under the other two inoculation methods.[Conclusions]The inoculation time and inoculation method of the pathogen both affect the inoculation effect.Among the three inoculation methods,the inoculation with rice grain-based inoculum at the bud stage is the most pathogenic to alfalfa seedlings,and can be popularized in the resistance evaluation of alfalfa to root diseases.展开更多
To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinc...To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinct inoculation methods（spot, filter paper and standard methods） at seedling, vegetative and reproductive stages. The results revealed that the spot and filter paper inoculation methods were successful in discerning susceptibility to the rice blast disease（P ≤ 0.05）. Disease susceptibility declined significantly from the vegetative to reproductive stages. The standard method was conducted at three different stages for pot plants grown inside the mist house. However, low temperatures did not produce disease symptoms except in a few genotypes. Among the 13 rice genotypes screened, AAT9 expressed a highly resistant response, and AAT4, AAT6, AAT10, AAT11, AAT13, AAT17 and AAT18 expressed resistance at various stages. The results will be useful for selecting elite genotypes for disease tolerance where rice blast is prevalent. In addition, the resistant genotypes can serve as a gene pool used in breeding programmes to develop new resistant genotypes.展开更多
The Agrobacterium-mediated transient expression system with conventional binary vectors is well established in tobacco leaves,while the same system applied to tomato leaflets has relatively low expression efficiency.H...The Agrobacterium-mediated transient expression system with conventional binary vectors is well established in tobacco leaves,while the same system applied to tomato leaflets has relatively low expression efficiency.However,impacts of the leaf age,inoculation method and incubation condition after Agrobacterium infiltration on transient protein expression efficiency are seldom investigated.In this study,we optimize Agrobacterium-mediated transient expression system using conventional binary vectors to achieve the high efficiency of target gene expression in tomato leaflets.We transiently express GFP and a nucleus-localized gene SlUVI4 fused with GFP in detached 10-,20-,and 30-day-old leaflets.The cutting points of leaflets are embedded in MS medium after the Agrobacterium-mediated vacuum infiltration,and all leaflets are kept in the dark before use.The 10-and 30-day-old leaflets have more damage than 20-day-old leaflets after the infiltration.展开更多
In order to establish a fast and effective high-throughput method for identifying maize resistance to Aspergillus flavus infection in the field,5 conidial concentrations and 3 inoculation methods were compared and opt...In order to establish a fast and effective high-throughput method for identifying maize resistance to Aspergillus flavus infection in the field,5 conidial concentrations and 3 inoculation methods were compared and optimized. A correlation model between disease levels and aflatoxin B1 accumulation was established. The results showed that inoculating maize inbred lines with the optimal conidial concentration of 1.0×10^6 c/mL could accurately show the different resistance levels of maize to A.flavus infection,and the spiral quantitative inoculation technique could effectively avoid the defect of calculation error caused by commonly used methods. The positive correlation model of resistance level and aflatoxin B1 accumulation could effectively predict the capability of maize being resistant to A.flavus. 8 resistant and 9 medium resistant maize inbred lines of the RIL population were identified.The spiral quantitative identification method realized the high-throughput identification of maize inbred lines resistant to A.flavus infection in the field,and the results have shown high accuracy,stability and repeatability.展开更多
[Objectives]This study was conducted to establish simple, efficient, stable, standardized and practical identification methods for sugarcane resistance to white leaf disease(SCWL), and promote the breeding for sugarca...[Objectives]This study was conducted to establish simple, efficient, stable, standardized and practical identification methods for sugarcane resistance to white leaf disease(SCWL), and promote the breeding for sugarcane resistance to SCWL. [Methods]The identification technology of sugarcane resistance to SCWL was systematically studied and explored from the aspects of sugarcane material treatment and planting, inoculation liquid preparation, inoculation method, disease investigation, grading standard formulation, etc., and two sets of simple, efficient, stable, standardized and practical accurate identification methods for sugarcane resistance to SCWL were created for the first time, namely, the seed cane coating inoculation method and the stem-cutting inoculation method at the growth stage. The seed cane coating inoculation method includes the steps of directly screening SCWL phytoplasma, extracting juice from cane and adding 10 times of sterile water to prepare an inoculation liquid, spraying seed cane on plastic film to keep moisture, planting the inoculated materials in barrels in an insect-proof greenhouse for cultivation, investigating the incidence rate 30 d after inoculation, and evaluating the disease resistance according to the 1-5 level standard. The method of stem-cutting inoculation includes the steps of directly screening sugarcane stems carrying SCWL phytoplasma and adding 10 times of sterile water to prepare an inoculation liquid, cultivating the identification materials in an insect-proof greenhouse, dropping 100 μl of the inoculation liquid into each root incision with a pipette gun at the age of 6 months, investigating the incidence rate 20 d after planting, and evaluating the disease resistance according to the 1-5 level standard. [Results] The two methods are similar to the natural transmission method. After inoculation, SCML occurred significantly, with high sensitivity and good reproducibility. The results of resistance identification were consistent with those of natural disease in the field. Through the two inoculation methods and field natural disease investigation, the resistance of 10 main cultivars to SCML was identified, which was true and reliable. [Conclusions] This study can provide standard varieties for identification of SCML resistance in the future.展开更多
基金This work was supported by the National Natural Science Foundation of China(32072399 and 32272641)the Fundamental Research Funds for the Central Universities(GK202201017 and GK202207024)the Program of Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests,China(MIMCP-202203).
文摘Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strategies to control the disease.As a soilborne pathogen,R.solanacearum naturally infects plants via roots.A huge limitation in studying plant-R.solanacearum interactions is the large variation of R.solanacearum infection assay due to the variable soil conditions and uneven inoculum exposure.Here,we developed a robust and reliable Petri-dish inoculation method which allows consistent and stable infection in young plant seedlings.This method is easy to use,takes about only 10 days from seed germination to the completion of inoculation assay,and requires less inoculum of bacteria as well as growth chamber space.We proved the efficacy of the seedling Petri-dish inoculation method by analyzing plant defense primed by molecular patterns,resistance of defense-related plant mutants,and virulence of R.solanacearum mutants.Furthermore,we demonstrated that the seedling Petri-dish inoculation method can be applied to other host plants such as tobacco and has great potential for high-throughput screening of resistant plant germplasms to bacterial wilt in the future.
文摘To establish a standard system for geneticstudies on sheath blight resistance, a field testwas conducted at the experimental farm ofYangzhou University to compare several pro-cedures for inoculating rice plants with R.solani Kuhn (RH9). The varieties used wereJasmine 85, Teqing (resistant or moderatelyresistant), and Lemont (susceptible). They
基金National Natural Science Foundation of China(31702169)Innovative Talent Cultivation Project of Heilongjiang Bayi Agricultural University(CXRC2017006)Scientific Research Innovation Fund for Postgraduates of Heilongjiang Bayi Agricultural University(YJSCX2018-Y39)。
文摘[Objectives]To find out the suitable inoculation method for Fusarium proliferatum.[Methods]Longmu 801 and TG4 were inoculated with rice grain-based inoculum at the bud and seedling stages and with root irrigation at the seedling stage,respectively,and then,the plant height,aboveground biomass,underground biomass,incidence rate and disease index of the alfalfa were determined to conduct comprehensive resistance evaluation.[Results]There was obvious difference in disease resistance between the two alfalfa varieties.Among the three inoculation methods,the relative plant height,relative aboveground biomass and relative underground biomass of Longmu 801 differed insignificantly(P>0.05),all around 100.There were significant differences in TG4 among different inoculation methods(P<0.05).The incidence rates and disease indices of Longmu 801 and TG4 inoculated with rice grain-based inoculum at the bud stage were the highest,and their incidence rates and disease indices were 73.3%and 100%,and 40 and 60,respectively,significantly higher than those under the other two inoculation methods.The incidence rates and disease indices of Longmu 801 and TG4 inoculated with rice grain-based inoculum at the seedling stage were the lowest,and their incidence rates and disease indices were 0%and 13.30%,and 0 and 5.33,respectively,significantly lower than those under the other two inoculation methods.[Conclusions]The inoculation time and inoculation method of the pathogen both affect the inoculation effect.Among the three inoculation methods,the inoculation with rice grain-based inoculum at the bud stage is the most pathogenic to alfalfa seedlings,and can be popularized in the resistance evaluation of alfalfa to root diseases.
文摘To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinct inoculation methods（spot, filter paper and standard methods） at seedling, vegetative and reproductive stages. The results revealed that the spot and filter paper inoculation methods were successful in discerning susceptibility to the rice blast disease（P ≤ 0.05）. Disease susceptibility declined significantly from the vegetative to reproductive stages. The standard method was conducted at three different stages for pot plants grown inside the mist house. However, low temperatures did not produce disease symptoms except in a few genotypes. Among the 13 rice genotypes screened, AAT9 expressed a highly resistant response, and AAT4, AAT6, AAT10, AAT11, AAT13, AAT17 and AAT18 expressed resistance at various stages. The results will be useful for selecting elite genotypes for disease tolerance where rice blast is prevalent. In addition, the resistant genotypes can serve as a gene pool used in breeding programmes to develop new resistant genotypes.
基金support of Taishan Scholar Foundation of Shandong Province(tsqn201909073,tsqn201812034)National Natural Science Foundation of China(31872951)。
文摘The Agrobacterium-mediated transient expression system with conventional binary vectors is well established in tobacco leaves,while the same system applied to tomato leaflets has relatively low expression efficiency.However,impacts of the leaf age,inoculation method and incubation condition after Agrobacterium infiltration on transient protein expression efficiency are seldom investigated.In this study,we optimize Agrobacterium-mediated transient expression system using conventional binary vectors to achieve the high efficiency of target gene expression in tomato leaflets.We transiently express GFP and a nucleus-localized gene SlUVI4 fused with GFP in detached 10-,20-,and 30-day-old leaflets.The cutting points of leaflets are embedded in MS medium after the Agrobacterium-mediated vacuum infiltration,and all leaflets are kept in the dark before use.The 10-and 30-day-old leaflets have more damage than 20-day-old leaflets after the infiltration.
文摘In order to establish a fast and effective high-throughput method for identifying maize resistance to Aspergillus flavus infection in the field,5 conidial concentrations and 3 inoculation methods were compared and optimized. A correlation model between disease levels and aflatoxin B1 accumulation was established. The results showed that inoculating maize inbred lines with the optimal conidial concentration of 1.0×10^6 c/mL could accurately show the different resistance levels of maize to A.flavus infection,and the spiral quantitative inoculation technique could effectively avoid the defect of calculation error caused by commonly used methods. The positive correlation model of resistance level and aflatoxin B1 accumulation could effectively predict the capability of maize being resistant to A.flavus. 8 resistant and 9 medium resistant maize inbred lines of the RIL population were identified.The spiral quantitative identification method realized the high-throughput identification of maize inbred lines resistant to A.flavus infection in the field,and the results have shown high accuracy,stability and repeatability.
基金Supported by National Natural Science Foundation of China (31760504)China Agriculture Research System of MOF and MARA(CARS-170303)+1 种基金Yunling Industry and Technology Leading Talent Training Program (2018LJRC56)Special Fund for the Construction of Modern Agricultural Industry Technology System in Yunnan Province。
文摘[Objectives]This study was conducted to establish simple, efficient, stable, standardized and practical identification methods for sugarcane resistance to white leaf disease(SCWL), and promote the breeding for sugarcane resistance to SCWL. [Methods]The identification technology of sugarcane resistance to SCWL was systematically studied and explored from the aspects of sugarcane material treatment and planting, inoculation liquid preparation, inoculation method, disease investigation, grading standard formulation, etc., and two sets of simple, efficient, stable, standardized and practical accurate identification methods for sugarcane resistance to SCWL were created for the first time, namely, the seed cane coating inoculation method and the stem-cutting inoculation method at the growth stage. The seed cane coating inoculation method includes the steps of directly screening SCWL phytoplasma, extracting juice from cane and adding 10 times of sterile water to prepare an inoculation liquid, spraying seed cane on plastic film to keep moisture, planting the inoculated materials in barrels in an insect-proof greenhouse for cultivation, investigating the incidence rate 30 d after inoculation, and evaluating the disease resistance according to the 1-5 level standard. The method of stem-cutting inoculation includes the steps of directly screening sugarcane stems carrying SCWL phytoplasma and adding 10 times of sterile water to prepare an inoculation liquid, cultivating the identification materials in an insect-proof greenhouse, dropping 100 μl of the inoculation liquid into each root incision with a pipette gun at the age of 6 months, investigating the incidence rate 20 d after planting, and evaluating the disease resistance according to the 1-5 level standard. [Results] The two methods are similar to the natural transmission method. After inoculation, SCML occurred significantly, with high sensitivity and good reproducibility. The results of resistance identification were consistent with those of natural disease in the field. Through the two inoculation methods and field natural disease investigation, the resistance of 10 main cultivars to SCML was identified, which was true and reliable. [Conclusions] This study can provide standard varieties for identification of SCML resistance in the future.
