The pathogen and characteristics, infection cycle, occurrence regularity and damage symptoms of sweet potato stem nematode disease were introduced in the paper. Moreover, the comprehensive prevention measures were put...The pathogen and characteristics, infection cycle, occurrence regularity and damage symptoms of sweet potato stem nematode disease were introduced in the paper. Moreover, the comprehensive prevention measures were put forward, including plant quarantine, agricultural control and chemical control. The study provided certain basis for reducing damages of sweet potato stem nematode disease and improving yield and quality of sweet potato.展开更多
Trichinella spiralis (T. spiralis), which is a cosmopolitan nematode that infects humans among other species, presents a complex host-parasite relationship that hinders the development of tools to eradicate the parasi...Trichinella spiralis (T. spiralis), which is a cosmopolitan nematode that infects humans among other species, presents a complex host-parasite relationship that hinders the development of tools to eradicate the parasitosis. The aim of this research was to analyze the host response during a primary infection with T. spiralis in five genetically different mouse lines of the CBi-IGE stock. Adult males from the CBi+, CBi−, CBi, CBi/L and CBi/C lines were infected with 1, 2 or 4 L1 larvae per g of body weight. In the chronic stage, the number of parasites per g of tissue (relative larval load, rLL) showed a significant host genotype-dose interaction, since it did not increase in the same way in the five genotypes. At the lowest dose, both CBii−and CBi/L mice were resistant while CBi+, CBi/C, and CBi were susceptible. At the highest dose, only CBi/L remained resistant, and CBi+ was the most susceptible. The reproductive capacity index of adult worms (RCI = rLL/infective dose) evinced only a genotype effect, allowing rating each line as resistant or susceptible regardless of dose. Animals receiving 2 L1 larvae were also sacrificed in the intestinal phase (6 and 13 days p-i) to determine the number of adult parasites (nAP) recovered in a small intestine segment, and female fecundity (Ff). No differences in nAP were observed among genotypes on day 6 p-i. nAP decreased between days 6 and 13 p-i, this reduction being different among genotypes and significant only in CBi/L and CBi/C. Ff decreased in CBi/L and CBi/C on day 13 p-i. At the time of infection, serum cytokine baseline values showed a Th1 orientation for genotype CBi/L (high IFN-γ and IL-2) and a Th2 for CBi+ (high IL-4 and IL-10).The variability in the response observed in this murine model suggests its potential usefulness to gain insight into the mechanisms that regulate host-parasite relationship.展开更多
The present review article demonstrates laboratory and field evaluations of entomopathogenic nematodes(EPNs)against different developmental stages of fruit flies.The virulence of the EPNs differed clearly even on the ...The present review article demonstrates laboratory and field evaluations of entomopathogenic nematodes(EPNs)against different developmental stages of fruit flies.The virulence of the EPNs differed clearly even on the same insect species and/or by the same nematode species.Such differences might be attributed to some reasons such as the method of treatment as well as the concentrations of the tested nematodes.Fruit flies are among the most important insect pests infesting vegetables and fruits causing considerable losses in the yields worldwide.In laboratory studies,the tested nematodes proved to be highly virulent to larvae as percentage of mortality may reach 100%.As for treated pupae,at different ages,the results are variable and controversially;some studies revealed their moderate or high susceptibility to nematode infection and others indicated low susceptibility or resistance to infection.Treated adults,or those emerged from treated larvae or pupae,are also susceptible to infection.In semi-field and field trials,EPNs proved to be successful for reducing the populations of some fruit flies with up to 85%at concentrations not less than 100 infective juveniles(IJs)/cm^2 of soil.However,the field applications of commercial EPNs have been recommended to be 2.5-5 x 10^9 IJs/ha(25-50 IJs/cm^2 of soil).展开更多
The bio-control potential of rhizospere bacteria Pseudomonas fluorescens against plant-parasite nematode had been demonstrated. P. fluorescens had shown the effect to enhance tobacco resistance to root-knot nematode M...The bio-control potential of rhizospere bacteria Pseudomonas fluorescens against plant-parasite nematode had been demonstrated. P. fluorescens had shown the effect to enhance tobacco resistance to root-knot nematode Meloidogyne incognita. Inoculation with P. fluorescens in tobacco could lead to significant reductions in the number of juveniles that penetrated tobacco root and further life stage development of the juveniles. The number of juveniles penetrated into tobacco root in treatment with P. fluorescens is significantly different from CK at 2DAI,6DAI,8DAI and 10 DAI. Significant reduction and delayed development of juveniles that penetrated into tobacco root and treated were observed in treatment at14 DAI,21DAI,28 DAI and 35 DAI. In addition,P. fluorescens treatment leads to a significant reduction in the number of eggs per egg-mass at 35 DAI. The results show P. fluorescens induced a continuously suppression on root-knot nematode M. incognita throughout their entire early infection phase of root penetration,subsequent life stage development and reproduction.展开更多
为明确番茄接种根结线虫后基因种类和表达量在转录水平的变化规律,利用RNA-seq对未接种及接种南方根结线虫2龄幼虫6、12、24和48 h的番茄进行转录组测序,探究番茄响应南方根结线虫侵染相关的关键转录因子,并采用qRT-PCR方法对测序结果...为明确番茄接种根结线虫后基因种类和表达量在转录水平的变化规律,利用RNA-seq对未接种及接种南方根结线虫2龄幼虫6、12、24和48 h的番茄进行转录组测序,探究番茄响应南方根结线虫侵染相关的关键转录因子,并采用qRT-PCR方法对测序结果进行验证。结果显示,接种南方根结线虫后6、12、24和48 h分别有350、390、580、1154个基因差异表达,其中差异表达转录因子分别为11、11、19、50个。这些转录因子属于15个家族,其中数量最多的为MYB家族和bHLH家族(均为20个),其次是ERF家族19个、WRKY家族15个、bZIP家族9个。南方根结线虫侵染过程差异表达最明显的主要为ERF、WRKY、MYB和bHLH家族转录因子,其中Solyc03g005520、Solyc02g094270和Solyc09g066350显著上调,接种后48 h log2FC分别为9.16、6.49和6.33;Solyc02g079280、Solyc12g100140和Solyc04g072460显著下调,接种后48 h log2FC分别为-2.60、-1.72和-1.70。qRT-PCR验证结果显示,6个随机选取基因的表达趋势与测序结果基本一致。以上结果表明,ERF、WRKY、MYB和bHLH家族转录因子可能参与番茄与南方根结线虫互作,在番茄响应南方根结线虫侵染反应中发挥着重要的调控作用。展开更多
为了给炉霍县养牛业健康发展提供寄生虫病防治指导与保障,采用粪便检查法对采集自四川省炉霍县部分地区的725份牛粪便样品进行消化道线虫和球虫感染情况调查。结果显示,牛消化道线虫和球虫的总感染率为23.0%(167/725)。其中,线虫的感染...为了给炉霍县养牛业健康发展提供寄生虫病防治指导与保障,采用粪便检查法对采集自四川省炉霍县部分地区的725份牛粪便样品进行消化道线虫和球虫感染情况调查。结果显示,牛消化道线虫和球虫的总感染率为23.0%(167/725)。其中,线虫的感染率为6.6%(48/725),平均每克粪便虫卵数(eggs per gram of feces,EPG)为129个;球虫感染率为16.4%(119/725),平均每克粪便卵囊数(oocysts per gram of feces,OPG)为244个,且无混合感染现象。在3个品种的牛群中,各个年龄段均存在线虫感染,不同品种牛的易感年龄有显著差异。球虫感染在各个年龄段均有发生,其感染率和感染强度随着年龄的增长呈下降趋势。在不同饲养方式方面,放养和半放养牦牛种群之间线虫的感染率存在极显著差异(P<0.01),而球虫的感染率差异不显著(P>0.05)。此外,线虫和球虫的感染率和感染强度在3个地区有显著差异(P<0.05),这可能与饲养环境有关。调查结果表明,当地牛普遍存在线虫与球虫感染,建议区域内牛场加强肠道寄生虫的监测工作,适时对牛群进行针对性驱虫。展开更多
基金Supported by Jiangsu Agricultural Science and Technology Independent Innovation Fund(CX(12)2030)Special Fund Project for Establishment of Modern Agricultural Industry System (CARS-11-C-03)
文摘The pathogen and characteristics, infection cycle, occurrence regularity and damage symptoms of sweet potato stem nematode disease were introduced in the paper. Moreover, the comprehensive prevention measures were put forward, including plant quarantine, agricultural control and chemical control. The study provided certain basis for reducing damages of sweet potato stem nematode disease and improving yield and quality of sweet potato.
文摘Trichinella spiralis (T. spiralis), which is a cosmopolitan nematode that infects humans among other species, presents a complex host-parasite relationship that hinders the development of tools to eradicate the parasitosis. The aim of this research was to analyze the host response during a primary infection with T. spiralis in five genetically different mouse lines of the CBi-IGE stock. Adult males from the CBi+, CBi−, CBi, CBi/L and CBi/C lines were infected with 1, 2 or 4 L1 larvae per g of body weight. In the chronic stage, the number of parasites per g of tissue (relative larval load, rLL) showed a significant host genotype-dose interaction, since it did not increase in the same way in the five genotypes. At the lowest dose, both CBii−and CBi/L mice were resistant while CBi+, CBi/C, and CBi were susceptible. At the highest dose, only CBi/L remained resistant, and CBi+ was the most susceptible. The reproductive capacity index of adult worms (RCI = rLL/infective dose) evinced only a genotype effect, allowing rating each line as resistant or susceptible regardless of dose. Animals receiving 2 L1 larvae were also sacrificed in the intestinal phase (6 and 13 days p-i) to determine the number of adult parasites (nAP) recovered in a small intestine segment, and female fecundity (Ff). No differences in nAP were observed among genotypes on day 6 p-i. nAP decreased between days 6 and 13 p-i, this reduction being different among genotypes and significant only in CBi/L and CBi/C. Ff decreased in CBi/L and CBi/C on day 13 p-i. At the time of infection, serum cytokine baseline values showed a Th1 orientation for genotype CBi/L (high IFN-γ and IL-2) and a Th2 for CBi+ (high IL-4 and IL-10).The variability in the response observed in this murine model suggests its potential usefulness to gain insight into the mechanisms that regulate host-parasite relationship.
文摘The present review article demonstrates laboratory and field evaluations of entomopathogenic nematodes(EPNs)against different developmental stages of fruit flies.The virulence of the EPNs differed clearly even on the same insect species and/or by the same nematode species.Such differences might be attributed to some reasons such as the method of treatment as well as the concentrations of the tested nematodes.Fruit flies are among the most important insect pests infesting vegetables and fruits causing considerable losses in the yields worldwide.In laboratory studies,the tested nematodes proved to be highly virulent to larvae as percentage of mortality may reach 100%.As for treated pupae,at different ages,the results are variable and controversially;some studies revealed their moderate or high susceptibility to nematode infection and others indicated low susceptibility or resistance to infection.Treated adults,or those emerged from treated larvae or pupae,are also susceptible to infection.In semi-field and field trials,EPNs proved to be successful for reducing the populations of some fruit flies with up to 85%at concentrations not less than 100 infective juveniles(IJs)/cm^2 of soil.However,the field applications of commercial EPNs have been recommended to be 2.5-5 x 10^9 IJs/ha(25-50 IJs/cm^2 of soil).
文摘The bio-control potential of rhizospere bacteria Pseudomonas fluorescens against plant-parasite nematode had been demonstrated. P. fluorescens had shown the effect to enhance tobacco resistance to root-knot nematode Meloidogyne incognita. Inoculation with P. fluorescens in tobacco could lead to significant reductions in the number of juveniles that penetrated tobacco root and further life stage development of the juveniles. The number of juveniles penetrated into tobacco root in treatment with P. fluorescens is significantly different from CK at 2DAI,6DAI,8DAI and 10 DAI. Significant reduction and delayed development of juveniles that penetrated into tobacco root and treated were observed in treatment at14 DAI,21DAI,28 DAI and 35 DAI. In addition,P. fluorescens treatment leads to a significant reduction in the number of eggs per egg-mass at 35 DAI. The results show P. fluorescens induced a continuously suppression on root-knot nematode M. incognita throughout their entire early infection phase of root penetration,subsequent life stage development and reproduction.
文摘为明确番茄接种根结线虫后基因种类和表达量在转录水平的变化规律,利用RNA-seq对未接种及接种南方根结线虫2龄幼虫6、12、24和48 h的番茄进行转录组测序,探究番茄响应南方根结线虫侵染相关的关键转录因子,并采用qRT-PCR方法对测序结果进行验证。结果显示,接种南方根结线虫后6、12、24和48 h分别有350、390、580、1154个基因差异表达,其中差异表达转录因子分别为11、11、19、50个。这些转录因子属于15个家族,其中数量最多的为MYB家族和bHLH家族(均为20个),其次是ERF家族19个、WRKY家族15个、bZIP家族9个。南方根结线虫侵染过程差异表达最明显的主要为ERF、WRKY、MYB和bHLH家族转录因子,其中Solyc03g005520、Solyc02g094270和Solyc09g066350显著上调,接种后48 h log2FC分别为9.16、6.49和6.33;Solyc02g079280、Solyc12g100140和Solyc04g072460显著下调,接种后48 h log2FC分别为-2.60、-1.72和-1.70。qRT-PCR验证结果显示,6个随机选取基因的表达趋势与测序结果基本一致。以上结果表明,ERF、WRKY、MYB和bHLH家族转录因子可能参与番茄与南方根结线虫互作,在番茄响应南方根结线虫侵染反应中发挥着重要的调控作用。
文摘为了给炉霍县养牛业健康发展提供寄生虫病防治指导与保障,采用粪便检查法对采集自四川省炉霍县部分地区的725份牛粪便样品进行消化道线虫和球虫感染情况调查。结果显示,牛消化道线虫和球虫的总感染率为23.0%(167/725)。其中,线虫的感染率为6.6%(48/725),平均每克粪便虫卵数(eggs per gram of feces,EPG)为129个;球虫感染率为16.4%(119/725),平均每克粪便卵囊数(oocysts per gram of feces,OPG)为244个,且无混合感染现象。在3个品种的牛群中,各个年龄段均存在线虫感染,不同品种牛的易感年龄有显著差异。球虫感染在各个年龄段均有发生,其感染率和感染强度随着年龄的增长呈下降趋势。在不同饲养方式方面,放养和半放养牦牛种群之间线虫的感染率存在极显著差异(P<0.01),而球虫的感染率差异不显著(P>0.05)。此外,线虫和球虫的感染率和感染强度在3个地区有显著差异(P<0.05),这可能与饲养环境有关。调查结果表明,当地牛普遍存在线虫与球虫感染,建议区域内牛场加强肠道寄生虫的监测工作,适时对牛群进行针对性驱虫。
