湖北省主栽甘薯品种病毒种类的血清学检测

对湖北省2个甘薯主产区内3个甘薯主栽品种,共计39份样本甘薯病毒病采用硝酸纤维膜酶联免疫检测法(NCM-ELISA)检测。结果表明,39份测试甘薯样本中,1个样本感染了甘薯退绿病毒(SPCFV),检出率为2.56%;18个样本感染了甘薯羽状斑驳病毒(SPFMV),检出率为46.15%;4个样本感染了甘薯潜隐病毒(SPLV),检出率为10.26%;1个样本感染了甘薯G病毒(SPVG),检出率为2.56%。3个主栽甘薯品种中,鄂薯6号病毒检出率最高,为66.67%;其次为徐薯22,病毒检出率为45.45%;福薯18的病毒检出率为43.75%。不同产地甘薯主栽品种带毒状况调查表明,鄂州主产区病毒病种类最多,病毒检出率最高。在5种受测目标病毒中,SPFMV的发生和危害最为严重,其单个采样点的样本感染率最高为52.12%;其次为SPLV,单个采样点的样本感染率为20.00%。2个主产区检测样品均未检测到甘薯退绿矮化病毒(SPCSV),但并不意味SPCSV在2个主产区没有发生,因此有待进一步大范围调查验证。     

南阳市甘薯病毒病调查与病原血清学鉴定

普查了南阳市 13县 (市、区 )甘薯病毒病的发生情况 ,以甘薯叶片作样本 ,采用NCM -ELISA方法检测病害样品 2 2 14个。结果表明 ,甘薯病毒病病田率达 10 0 % ,品种发病率 10 0 % ,未脱毒甘薯田病株率平均为 75 .9% ,脱毒甘薯田平均病株率 12 .1% ;初步认定南阳市甘薯病毒病病原至少有 6种 ,即SPFMV、SPLV、SPCFV、SPMMV、C - 6、C - 8。以SPFMV和SPLV为主。     

Symptom expression and seed transmission of alfalfa mosaic virus and potato yellowing virus (SB-22) inSolanum brevidens andS. etuberosum

Summary Solanum brevidens showed calico mosaic symptoms in all the leaves, butS. etuberosum yellowing and yellow mosaic only in the top leaves, following graft-inoculation with alfalfa mosaic virus (AMV). The South American potato virus SB-22 infected latentlyS. brevidens following graft-inoculation, whereasS. etuberosum was not infected. AMV was not transmitted to the ovules of AMV-infectedS. brevidens andS. etuberosum. However, AMV was transmitted to the seeds ofS. etuberosum through pollen, resulting in 0.9% infected seeds.S. brevidens infected by SB-22 produced up to 20.2% of virus-infected germinable seed, and in some of the seed lots of infectedS. brevidens the germination rate was as low as 1.0%.     

Assessment of latent infection frequency in progeny tubers of advanced potatoclones resistant to bacterial wilt: A new selection criterion

Summary This paper reports results of a 3-year evaluation of CIP advanced potato clones in a bacterial wilt-infested field (race 3) in Peru. Clones resistant or moderately resistant to wilt were selected and all tubers harvested from each clone were tested for latent infection byRalstonia solanacearum using a sensitive serological technique developed at CIP. A sampling strategy to estimate accurately the frequency of infected tubers in the clones has been evaluated. This method will allow consideration of tuber latent infection as a new selection criterion in breeding for resistance to bacterial wilt. Thirteen clones were found resistant to wilt in all three evaluations (i.e.≤6% wilt), from which five had no wilt in all trials. However, all clones harboured latent infection in tubers averaging 30%. Analysing 30 tubers/clone provides an accurate estimation of the proportion of infected tubers with a high precision level.     

NCM-ELISA检测马铃薯Y病毒(PVY)技术的研究及应用

血清学方法是病毒检测的主要手段。本试验通过对马铃薯Y病毒(PVY)的提纯,免疫家兔制备PVY抗血清,并提取PYV免疫球蛋白IgG作为NCM-ELISA反应为一抗,以市售羊抗兔抗血清为二抗,在硝酸纤维素膜(NCM)上进行NCM-ELISA反应检测PVY,建立PVY NCM-ELISA检测反应体系。试验结果显示,NCM-ELISA具有反应特异性强,灵敏度高的优点,检测植物叶片样品的最高稀释度可达到1:250。通过对田间40份样品的NCM-ELISA和DAS-ELISA检测比较,其检测结果吻合率达到100%。由于NCM-ELISA方法可以将样品点在硝酸纤维素膜上,并且可贮存几个星期或将膜送到其他实验室进行检测,因此具有操作简单,使用方便,检测成本低等优点。     

应用GAR-HRP进行甘薯病毒NCM-ELISA检测试验

分别采用辣根过氧化物酶标记的羊抗兔抗体 (GAR -HRP)和碱性磷酸酯酶标记的羊抗兔抗体(GAR -AP) ,对甘薯羽状斑驳病毒 (SPFMV)、甘薯潜隐病毒 (SPLV)、甘薯轻斑驳病毒 (SPMMV)及甘薯褪绿病毒(SPCFV)进行NCM -ELISA检测 ,结果表明 ,采用GAR -HRP进行NCM -ELISA检测对于SPFMV、SPLV、SPM MV、SPCFV同样有效 ,且特异性高 ,重现性好 ,在某些方面优于GAR -AP。对于国内危害甘薯的SPFMV、SPLV等主要病毒 ,采用GAR -HRP进行ELISA检测更加经济有效 ,是切实可行的     

马铃薯青枯病菌的PE-ELISA检测

PE ELISA (Post EnrichmentEnzyme -linkedImmunosorbentAssay)是一种快速、经济、有效的马铃薯青枯菌检测方法 ,较普通NCM ELISA方法灵敏度提高 10 0万倍 ,与DAS -ELISA、NASH等方法一样灵敏、可靠 ,特别是对处于潜伏期感染而没有表现出症状的马铃薯块茎的检测更为有效     

Optimisation of sample size for the detection of latent infection byRalstonia solanacearum in potato seed tubers in the highlands of Peru

Summary A sampling strategy was evaluated in the Andean highlands of Peru to optimise the detection ofRalstonia solanacearum in seed tubers harvested from symptomless crops. A sensitive and specific serological method developed at CIP was used to detect the pathogen in latently infected tubers. Optimum sample size was evaluated for symptomless crops after analysing various numbers of composite samples and using a binomial distribution model to calculate the detection probabilities.R. solanacearum was detected in all lots from fields with visible symptoms, so validating the detection technique. About half of the seed lots from apparently healthy fields at altitudes of up to 3,100 m were found positive for the pathogen.R. solanacearum was detected with 99% probability in samples of 350 tubers from seed lots from symptomless crops. This number of seed tubers could feasibly be processed in a seed-health test without incurring too high a cost for labour and materials.     

烟粉虱中甘薯褪绿矮化病毒（SPCSV）的快速检测技术

建立了利用NCM-ELISA、RT-PCR和半巢式RT-PCR检测烟粉虱中SPCSV的方法,比较了3种检测方法的灵敏性。结果表明,NCM-ELISA最低能从16头带毒烟粉虱中检测出SPCSV;RT-PCR能稳定地从3头以上带毒烟粉虱中检测出SPCSV;半巢式RT-PCR能稳定地从单头烟粉虱中检测出SPCSV。检测灵敏性研究表明,用体外转录的RNA作为核酸模板,RT-PCR可检测的最低浓度为5.69×104拷贝/μL,半巢式RT-PCR为5.69×101拷贝/μL,说明半巢式RT-PCR检测方法的灵敏性比RT-PCR高1 000倍。     

马铃薯种薯青枯病菌的NCM-ELISA检测

利用NCM-ELISA方法对来自云南省3个县(市)50个样本的马铃薯种薯青枯病菌的带菌量进行检测,检查是否具有青枯病潜在感染。结果表明:寻甸的24个样品中11个带菌;宣威的17个样品中10个带菌;来自昭通的所有样品都不带菌。其中马铃薯主栽地区的主栽品种的青枯病潜在感染量较大。