[Objective] The purpose of the study is to breed Micromonospora car- bonacea highly producing antibiotics and then to improve the antibiotic production. [Method] Sodium Nitrite mutagenesis, combined with rifampicin re...[Objective] The purpose of the study is to breed Micromonospora car- bonacea highly producing antibiotics and then to improve the antibiotic production. [Method] Sodium Nitrite mutagenesis, combined with rifampicin resistance screening, was used in mutation breeding of M. carbonacea highly producing antibiotics from the strain of M. carbonacea JXNU-I. [Result] The overproducing strain JXNU-1-16- Y65 was screened with the production of antibiotics 266.05% more than that of the original strain. [Conclusion] The effectiveness of sodium nitrite mutation in breeding microorganisms highly producing antibiotic was proved, and the study may lay the foundation on further development and application of the antibiotic from M. car- bonacea JXNU-1.展开更多
During 1984-1988,2,231 varieties(lines)from International Rice Testing Program(IRTP)were evaluated and screened for resistance to riceblast(Bl),bacterial blight(BB),sheath blight
This study aimed to clarify the pathogen composition,biological characteristics,infection patterns,and effective control agents for panicle blight of rice in Heilongjiang Province.Diseased panicles were collected from...This study aimed to clarify the pathogen composition,biological characteristics,infection patterns,and effective control agents for panicle blight of rice in Heilongjiang Province.Diseased panicles were collected from different rice-growing areas in Heilongjiang Province and subjected to tissue isolation,pathogenicity tests,morphological observation,and molecular identification.The primary pathogens identified were Fusarium graminearum,Alternaria alternata and Nigrospora oryzae.The biological characteristics of these three pathogens were systematically investigated.Pathogenicity assays revealed that F.graminearum exhibited the strongest pathogenicity,followed by A.alternata,while N.oryzae was the weakest.In vitro toxicity tests screened highly effective fungicides:75%trifloxystrobin-tebuconazole showed the best inhibitory effect against F.graminearum(EC50=0.0140μg·mL^(-1));30%tebuconazole-azoxystrobin was the most effective against A.alternata(EC50=0.0060μg·mL^(-1))and N.oryzae(EC50=0.0310μg·mL^(-1)).展开更多
Understanding the performance of new crop genotypes for traits of relevance is important in selecting potential cultivars to satisfy end-users. The objective of this study was to determine the performance of new banan...Understanding the performance of new crop genotypes for traits of relevance is important in selecting potential cultivars to satisfy end-users. The objective of this study was to determine the performance of new banana genotypes for bunch mass (BMS) and BMS-related traits, resistance to black Sigatoka and sensory attributes. Eight cooking banana genotypes consisting of six new hybrid genotypes selected from advanced breeding trials and two control cultivars were evaluated in a randomized complete block design for three crop cycles at three locations in Uganda. Genotype, location, crop cycle and their interaction effects were significantly different for most traits assessed. The overall top two genotypes (“9058K-2” and “8099K-16”) combining high BMS, resistance to black Sigatoka and acceptable sensory attributes were identified. These genotypes are suggested as potential commercial cultivars for release to farmers in Uganda and/or other East African countries with similar environmental conditions to those where the genotypes were tested. It should be noted that high BMS/yield and resistance to diseases are not the only factors to consider when selecting banana genotypes that meet end-user needs. A combination of high BMS/yield, acceptable sensory attributes and resistance to diseases essentially influence the selection process of banana cultivars.展开更多
Started from salicylic acid（SA） and related commercialized plant activators,based on molecular threedimensional shape and pharmacophore similarity comparison（SHAFTS）,a new lead compound benzotriazole was predicted...Started from salicylic acid（SA） and related commercialized plant activators,based on molecular threedimensional shape and pharmacophore similarity comparison（SHAFTS）,a new lead compound benzotriazole was predicted and a series of benzotriazole derivatives were designed and synthesized.The bioassay showed that benzotriazole had high activity against a broad spectrum of diseases including fungi and oomycetes in vivo,but no activity in vitro.And the introduction of proper groups at the1＇-position and 5＇-position was beneficial to the activity.So,they had the potential to be exploited as novel plant activators.展开更多
Background The prevalence of chronic kidney disease （CKD） and prediabetes has increased in China, and at different rates in different locations. Therefore a community-based screening research was conducted in order ...Background The prevalence of chronic kidney disease （CKD） and prediabetes has increased in China, and at different rates in different locations. Therefore a community-based screening research was conducted in order to determine the prevalence of CKD and prediabetes, and to analyze associated risk factors of CKD and prediabetes in a city of Southern China.Methods A total of 7801 community residents aged 18 year and older from 6 communities were screened by a stratified random cluster sampling method. An estimated glomerular filtration rate （eGFR）, albuminuria, fasting plasma glucose （FPG）, and homeostatic model assessment of insulin resistance （HOMA-IR） were measured. Age-standardized prevalence was calculated by the direct method with the use of data on the population distribution in China in 2006. Multivariate logistic analysis was used to analyze the risk factors of CKD and ＂prediabetes, and association of insulin resistance （IR） with CKD and prediabetes was analyzed.Results The age-standardized prevalence of CKD was 12.5%, eGFR 〈60 ml.min^-1.1.73 m2 was 2.7% and ACR （albumin to creatinine ratio） 〉30 mg/g was 10.3%. The age-standardized prevalence of prediabetes was 12.1%. Logistic regression suggests that IR was a common independent risk factor of CKD and prediabetes. Further analysis show that HOMA-IR was increased with the aggravation of kidney injury and FPG. Conclusion CKD and prediabetes have become a major public health problem in Zhuhai, Southern China; insulin resistance may be an important risk factor.展开更多
Background：Screening on multidrug-resistant tuberculosis （MDR-TB） has been limited to the serious TB subpopulations excluding the new TB patients.This study aimed to examine MDR-TB burden among the new TB patients....Background：Screening on multidrug-resistant tuberculosis （MDR-TB） has been limited to the serious TB subpopulations excluding the new TB patients.This study aimed to examine MDR-TB burden among the new TB patients.Methods：We conducted a study in Zhejiang Province during 2009-2013 to screen for MDR-TB patients among the low MDR-TB risk patients and five subpopulations of high MDR-TB risk patients.The number,prevalence,and trend of MDR-TB were compared while the logistic regression model was used to examine risk factors related to MDR-TB.Results：A total of 200 and 791 MDR-TB cases were,respectively,identified from the 9830 new TB cases and 2372 high-risk suspects who took MDR-TB screening from 2009 to 2013.The MDR-TB rates went down in both of the new TB patients and five MDR-TB high-risk groups over the study time,but the percentage of MDR-TB patients identified from the new TB patients in all diagnosed MDR-TB cases kept stable from 28.3% in 2011 to 27.0% in 2012 to 26.0% in 2013.Conclusions：The study indicated that MDR-TB burden among new TB patients was high,thus screening for MDR-TB among the new TB patients should be recommended in China as well as in the similar situation worldwide.展开更多
The pea enation mosaic disease(PEMD)causes significant yield losses worldwide.PEMD is caused by two taxonomically unrelated but symbiotic viruses,pea enation mosaic virus 1(PEMV-1)and pea enation mosaic virus 2(PEMV-2...The pea enation mosaic disease(PEMD)causes significant yield losses worldwide.PEMD is caused by two taxonomically unrelated but symbiotic viruses,pea enation mosaic virus 1(PEMV-1)and pea enation mosaic virus 2(PEMV-2).In this study,the complete genomes of four isolates of PEMV-1 and PEMV-2 from Yunnan Province of China were determined and analyzed.The four isolates of PEMV-1 or PEMV-2 shared≥98.7%nucleotide sequence identities at whole genome level.The four Chinese PEMV-1 isolates were most closely related to PEMV-1-Ramsey-1 with nucleotide sequence identities of 97.8–98.0%,while the four Chinese PEMV-2 isolates were most closely related to PEMV-2-DSMZ PV-0088,with nucleotide sequence identities of 94.3–94.5%.The two full-length infectious cDNA clones of the Yunnan-Dali isolates of the two viruses(PEMV-1-YDL and PEMV-2-YDL)were constructed.Co-inoculation of PEMV-1-YDL and PEMV-2-YDL in pea seedlings caused systemic infection,with typical enation and mosaic symptoms on new leaves after inoculation,while the inoculated Nicotiana benthamiana plants showed curling symptoms.Inoculation of pea seedlings with either PEMV-1-YDL or PEMV-2-YDL did not cause obvious symptoms on the new leaves.It has been known that PEMV-2 helps the systemic infection of PEMV-1.However,our results showed that PEMV-1-YDL alone could cause a systemic infection.The pathogenicity of the two infectious clones was tested on different pea cultivars,and some cultivars were PEMD-tolerant.This is the first report of the infectious clones constructed from the Chinese isolates of PEMV-1 and PEMV-2.The current approach will facilitate determination of the synergistic relationship between PEMV-1 and PEMV-2 and their interactions with the host plant by reverse genetic analysis.展开更多
Rice yellow mottle disease(RYMD)continues to constrain rice production in Africa.Rice yellow mottle virus(RYMV),which belongs to the Sobemovirus genus,is the causal agent of RYMD.In Kenya,previous studies on RYMV most...Rice yellow mottle disease(RYMD)continues to constrain rice production in Africa.Rice yellow mottle virus(RYMV),which belongs to the Sobemovirus genus,is the causal agent of RYMD.In Kenya,previous studies on RYMV mostly focused on western Kenya,ignoring the central and coastal regions,which are also important areas for rice cultivation in the country.This has resulted in incomplete data on RYMD outbreaks.This study aimed to determine the prevalence of RYMD in the farmers’fields,and the genetic diversity of the RYMV based on the coat protein gene.Field surveys were carried out in Kenya’s rice-growing regions between May and July 2023 to determine disease incidences using the IRRI Standard Evaluation Scale(SES)for rice.Symptom observations and serological tests confirmed the presence of RYMV in all surveyed rice cultivation areas.The presence of RYMV was detected in Kirinyaga,Tana River,and Taita Taveta counties of Kenya,representing the field report of its occurrence in these regions.Disease incidence and severity analysis using one-way ANOVA showed no significant difference in RYMD incidence among the rice irrigation schemes(F(6,29)=1.838,P=0.1265).Sequencing results of the coat protein gene(ORF4 region)revealed that the RYMV isolates in this study could be classified as S4ke,S4ug,and S4mg strains in the East Africa lineage.The discovery of the RYMV strain S4mg in Kenya runs counter to the gradual strain of breaking up and moving away that has been established in Africa over the past two centuries.Results showed that RYMV is present in all the rice-growing regions under study and exhibits intra-strain diversity in Kenya.Incorporating resistance genes into extensively grown rice cultivars is crucial for preventing the spread of the rice yellow mottle virus.展开更多
基金Supported by Science and Technology Planning Project of Jiangxi Province of China(20112BBF60026)~~
文摘[Objective] The purpose of the study is to breed Micromonospora car- bonacea highly producing antibiotics and then to improve the antibiotic production. [Method] Sodium Nitrite mutagenesis, combined with rifampicin resistance screening, was used in mutation breeding of M. carbonacea highly producing antibiotics from the strain of M. carbonacea JXNU-I. [Result] The overproducing strain JXNU-1-16- Y65 was screened with the production of antibiotics 266.05% more than that of the original strain. [Conclusion] The effectiveness of sodium nitrite mutation in breeding microorganisms highly producing antibiotic was proved, and the study may lay the foundation on further development and application of the antibiotic from M. car- bonacea JXNU-1.
文摘During 1984-1988,2,231 varieties(lines)from International Rice Testing Program(IRTP)were evaluated and screened for resistance to riceblast(Bl),bacterial blight(BB),sheath blight
基金Supported by the Green Plant Protection Project in Heilongjiang Province(2130108)the Key R&D Program Project of Heilongjiang Province(2023ZX02B0502)the Heilongjiang Province Rice Modern Agriculture Industry Technology Collaborative Innovation System Project(2025)。
文摘This study aimed to clarify the pathogen composition,biological characteristics,infection patterns,and effective control agents for panicle blight of rice in Heilongjiang Province.Diseased panicles were collected from different rice-growing areas in Heilongjiang Province and subjected to tissue isolation,pathogenicity tests,morphological observation,and molecular identification.The primary pathogens identified were Fusarium graminearum,Alternaria alternata and Nigrospora oryzae.The biological characteristics of these three pathogens were systematically investigated.Pathogenicity assays revealed that F.graminearum exhibited the strongest pathogenicity,followed by A.alternata,while N.oryzae was the weakest.In vitro toxicity tests screened highly effective fungicides:75%trifloxystrobin-tebuconazole showed the best inhibitory effect against F.graminearum(EC50=0.0140μg·mL^(-1));30%tebuconazole-azoxystrobin was the most effective against A.alternata(EC50=0.0060μg·mL^(-1))and N.oryzae(EC50=0.0310μg·mL^(-1)).
文摘Understanding the performance of new crop genotypes for traits of relevance is important in selecting potential cultivars to satisfy end-users. The objective of this study was to determine the performance of new banana genotypes for bunch mass (BMS) and BMS-related traits, resistance to black Sigatoka and sensory attributes. Eight cooking banana genotypes consisting of six new hybrid genotypes selected from advanced breeding trials and two control cultivars were evaluated in a randomized complete block design for three crop cycles at three locations in Uganda. Genotype, location, crop cycle and their interaction effects were significantly different for most traits assessed. The overall top two genotypes (“9058K-2” and “8099K-16”) combining high BMS, resistance to black Sigatoka and acceptable sensory attributes were identified. These genotypes are suggested as potential commercial cultivars for release to farmers in Uganda and/or other East African countries with similar environmental conditions to those where the genotypes were tested. It should be noted that high BMS/yield and resistance to diseases are not the only factors to consider when selecting banana genotypes that meet end-user needs. A combination of high BMS/yield, acceptable sensory attributes and resistance to diseases essentially influence the selection process of banana cultivars.
基金financially supported by the National Basic Research Program of China(973 Program,No.2010CB126100)the National High Technology Research and Development Program of China(863 Program,No.2011AA10A207)+1 种基金the Shanghai Leading Academic Discipline Project(B507)the Fundamental Research Funds for the Central Universities
文摘Started from salicylic acid（SA） and related commercialized plant activators,based on molecular threedimensional shape and pharmacophore similarity comparison（SHAFTS）,a new lead compound benzotriazole was predicted and a series of benzotriazole derivatives were designed and synthesized.The bioassay showed that benzotriazole had high activity against a broad spectrum of diseases including fungi and oomycetes in vivo,but no activity in vitro.And the introduction of proper groups at the1＇-position and 5＇-position was beneficial to the activity.So,they had the potential to be exploited as novel plant activators.
文摘Background The prevalence of chronic kidney disease （CKD） and prediabetes has increased in China, and at different rates in different locations. Therefore a community-based screening research was conducted in order to determine the prevalence of CKD and prediabetes, and to analyze associated risk factors of CKD and prediabetes in a city of Southern China.Methods A total of 7801 community residents aged 18 year and older from 6 communities were screened by a stratified random cluster sampling method. An estimated glomerular filtration rate （eGFR）, albuminuria, fasting plasma glucose （FPG）, and homeostatic model assessment of insulin resistance （HOMA-IR） were measured. Age-standardized prevalence was calculated by the direct method with the use of data on the population distribution in China in 2006. Multivariate logistic analysis was used to analyze the risk factors of CKD and ＂prediabetes, and association of insulin resistance （IR） with CKD and prediabetes was analyzed.Results The age-standardized prevalence of CKD was 12.5%, eGFR 〈60 ml.min^-1.1.73 m2 was 2.7% and ACR （albumin to creatinine ratio） 〉30 mg/g was 10.3%. The age-standardized prevalence of prediabetes was 12.1%. Logistic regression suggests that IR was a common independent risk factor of CKD and prediabetes. Further analysis show that HOMA-IR was increased with the aggravation of kidney injury and FPG. Conclusion CKD and prediabetes have become a major public health problem in Zhuhai, Southern China; insulin resistance may be an important risk factor.
文摘Background：Screening on multidrug-resistant tuberculosis （MDR-TB） has been limited to the serious TB subpopulations excluding the new TB patients.This study aimed to examine MDR-TB burden among the new TB patients.Methods：We conducted a study in Zhejiang Province during 2009-2013 to screen for MDR-TB patients among the low MDR-TB risk patients and five subpopulations of high MDR-TB risk patients.The number,prevalence,and trend of MDR-TB were compared while the logistic regression model was used to examine risk factors related to MDR-TB.Results：A total of 200 and 791 MDR-TB cases were,respectively,identified from the 9830 new TB cases and 2372 high-risk suspects who took MDR-TB screening from 2009 to 2013.The MDR-TB rates went down in both of the new TB patients and five MDR-TB high-risk groups over the study time,but the percentage of MDR-TB patients identified from the new TB patients in all diagnosed MDR-TB cases kept stable from 28.3% in 2011 to 27.0% in 2012 to 26.0% in 2013.Conclusions：The study indicated that MDR-TB burden among new TB patients was high,thus screening for MDR-TB among the new TB patients should be recommended in China as well as in the similar situation worldwide.
基金supported by the Science and Technology Project of Yunnan Province,China(202005AF150040).
文摘The pea enation mosaic disease(PEMD)causes significant yield losses worldwide.PEMD is caused by two taxonomically unrelated but symbiotic viruses,pea enation mosaic virus 1(PEMV-1)and pea enation mosaic virus 2(PEMV-2).In this study,the complete genomes of four isolates of PEMV-1 and PEMV-2 from Yunnan Province of China were determined and analyzed.The four isolates of PEMV-1 or PEMV-2 shared≥98.7%nucleotide sequence identities at whole genome level.The four Chinese PEMV-1 isolates were most closely related to PEMV-1-Ramsey-1 with nucleotide sequence identities of 97.8–98.0%,while the four Chinese PEMV-2 isolates were most closely related to PEMV-2-DSMZ PV-0088,with nucleotide sequence identities of 94.3–94.5%.The two full-length infectious cDNA clones of the Yunnan-Dali isolates of the two viruses(PEMV-1-YDL and PEMV-2-YDL)were constructed.Co-inoculation of PEMV-1-YDL and PEMV-2-YDL in pea seedlings caused systemic infection,with typical enation and mosaic symptoms on new leaves after inoculation,while the inoculated Nicotiana benthamiana plants showed curling symptoms.Inoculation of pea seedlings with either PEMV-1-YDL or PEMV-2-YDL did not cause obvious symptoms on the new leaves.It has been known that PEMV-2 helps the systemic infection of PEMV-1.However,our results showed that PEMV-1-YDL alone could cause a systemic infection.The pathogenicity of the two infectious clones was tested on different pea cultivars,and some cultivars were PEMD-tolerant.This is the first report of the infectious clones constructed from the Chinese isolates of PEMV-1 and PEMV-2.The current approach will facilitate determination of the synergistic relationship between PEMV-1 and PEMV-2 and their interactions with the host plant by reverse genetic analysis.
文摘Rice yellow mottle disease(RYMD)continues to constrain rice production in Africa.Rice yellow mottle virus(RYMV),which belongs to the Sobemovirus genus,is the causal agent of RYMD.In Kenya,previous studies on RYMV mostly focused on western Kenya,ignoring the central and coastal regions,which are also important areas for rice cultivation in the country.This has resulted in incomplete data on RYMD outbreaks.This study aimed to determine the prevalence of RYMD in the farmers’fields,and the genetic diversity of the RYMV based on the coat protein gene.Field surveys were carried out in Kenya’s rice-growing regions between May and July 2023 to determine disease incidences using the IRRI Standard Evaluation Scale(SES)for rice.Symptom observations and serological tests confirmed the presence of RYMV in all surveyed rice cultivation areas.The presence of RYMV was detected in Kirinyaga,Tana River,and Taita Taveta counties of Kenya,representing the field report of its occurrence in these regions.Disease incidence and severity analysis using one-way ANOVA showed no significant difference in RYMD incidence among the rice irrigation schemes(F(6,29)=1.838,P=0.1265).Sequencing results of the coat protein gene(ORF4 region)revealed that the RYMV isolates in this study could be classified as S4ke,S4ug,and S4mg strains in the East Africa lineage.The discovery of the RYMV strain S4mg in Kenya runs counter to the gradual strain of breaking up and moving away that has been established in Africa over the past two centuries.Results showed that RYMV is present in all the rice-growing regions under study and exhibits intra-strain diversity in Kenya.Incorporating resistance genes into extensively grown rice cultivars is crucial for preventing the spread of the rice yellow mottle virus.
