大豆病毒病的类型及其病原鉴定

东北地区发生的大豆病毒病,其症状主要为黄斑花叶、顶枯、皱缩花叶及卷叶等类型。根据对50个毒株测定的结果,这些病害的病原均属于大豆花叶病毒(SMV),但由于它们所引起的症状不同,可认为是三个不同的株系,即黄斑株系(SMV—Y,引起黄斑花叶和皱缩)、顶枯株系(SMV—T,引起顶枯)和卷叶株系(SMV—C,引起卷叶)。三个株系都由种子带毒传病,田间可由大豆蚜传染,属口针带毒型,只能系统侵染大豆及秣食豆,在菜豆品种家雀蛋上形成局部斑,不能侵染豇豆、眉豆、豌豆、普通烟、苋色藜等,在多种其他菜豆品种上无症。SMV—Y 的稳定性较低,失毒温度为50°～55℃,稀释限点为10~(-2),体外保毒期为12小时至两天,病毒粒体为线状。     

低浓度Cu和Cd复合污染对小白菜生理生化特性的影响

采用盆栽试验,研究了不同质量浓度Cu(0,25,50,100,200 mg/kg)和Cd(0,1.0,10.0 mg/kg)及其复合污染对小白菜生理生化指标的影响。以不添加Cu和Cd为对照组。结果表明,小白菜外观正常,没有出现Cd中毒症状,但是Cd-Cu复合处理组小白菜的生物量、叶绿素a、叶绿素总量、叶绿素a/b值都低于对照及单一处理组,Cu、Cd复合处理对叶绿素a的影响程度大于叶绿素b;复合处理组的细胞膜透性明显低于单一处理组,硝酸还原酶(NR)活性显著高于对照及单一处理组,过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性高于相同浓度Cd单一处理组。     

甘草不同来源愈伤组织过氧化物酶分析

采用聚丙烯酰胺凝胶电泳法和分光光度法,对乌拉尔甘草的根状茎、芽、叶诱导的愈伤组织中过氧化物同功酶进行电泳和活性分析。结果得出:不同来源的愈伤组织中过氧化物酶酶谱分为A、B、C三个区域,其中活性最强的是A区和C区,所有供试样品出现3种酶谱谱型,6种酶谱谱带;在进行酶活性测定时,叶的愈伤组织中过氧化物酶活性最高,芽的次之,根状茎的最低,过氧化物酶活性过高不利于愈伤组织生长。确立的2种特征酶谱带(P2和P6),4种差异酶谱谱带(P1、P3、P4和P5),为乌拉尔甘草种的鉴别及脱分化与再分化的细胞生物学机制研究提供了一定的参考依据。     

水稻抗瘟性与过氧化物酶同工酶的初步研究

本研究采用垂直板聚丙烯酰胺凝胶电泳的方法,测定了11个稻瘟菌小种接种的18个水稻品种(品系)的过氧化物酶同工酶。结果表明,受侵染植株与对照间的同工酶谱带数目及其相对迁移率(Rf)无明显差异、无新谱带出现。说明受侵染植株与对照间过氧化物酶同工酶的代谢途径没有变化;但过氧化物酶同工酶的活性与水稻抗瘟性有密切关系。接种7天后植株体内该酶的活性非亲和组合显著大于亲和组合。     

白菜孤丁病毒一个枯纹株系的鉴定

1962年春开始,对本所試驗地大白菜采种株上呈現花叶并有枯紋症状的病株毒原(62—4号)进行鑑定研究。 1.寄主反应及症状:人工接种7科14属25种和品种的植物。結果可侵染十字花科、茄科、菊科、藜科及莧科19种和品种的植物,并表現不同的症状反应: (1)花叶症及枯紋:接种大白菜后十天左右,在接种叶上呈現不甚明显的褪綠暈斑,随后新生幼叶皺縮,明脉及褪綠花叶。在中外层較老的病叶上常呈現淡黄色綫条状或折綫形枯紋,或多角形、不規則形的枯斑。在蘿卜、油青菜、花椰菜及芥菜上也产生相似的褪綠花叶症、枯紋或枯斑。 (2)花叶症:接种甘蓝后不久,开始叶脉变黄,叶片呈褪綠黄点状花叶,后变成黄綠色斑块。叶脉縮短,叶片皺縮。症状較孤丁1号严     

恶苗病菌对不同水稻品种过氧化物酶同工酶影响的初步研究

用垂直板状聚丙烯酰胺凝胶电泳方法,对抗、感水稻恶苗病不同类型的6个水稻品种的过氧化物酶同工酶进行了研究。提出了水稻芽期过氧化物酶同工酶基本谱型,模式酶带共7条。抗感程度不同的品种接种后过氧化物酶同工酶酶谱存在着明显差异,主要出现在C区谱带上。     

云南西部烟区一种新的烟草病害——烟草丛枝症病害

近年来在云南大理、保山等西部烟区暴发流行一种新的烟草病害 ,暂称为烟草丛枝症病害。该病在大田烤烟上的主要症状为 :叶片先出现淡褐色蚀点斑并发展成坏死斑 ,随后新生叶坏死症状减轻 ,叶片逐渐变小变圆并褪绿或黄化。在发生褪绿的叶片脉间组织颜色较淡 (灰色或浅白色 ) ,隐约可见斑驳 ;有时可见叶面皱缩 ,产生疱斑 ,叶缘向背后翻卷 ,顶端优势丧失 ,腋芽比健株提早萌发 ,节间缩短 ,植株矮缩 ,生长缓慢。病株为密生小叶、小枝的丛枝状塔型 (封面彩图 )。苗期感病的烟株严重矮缩且不开花 ,由于为整株性感病 ,病株无任何经济价值。团棵期和旺…     

过氧化物酶及其同工酶与小麦抗赤霉病性的关系

 本文报道了对赤霉病抗性不同的五个小麦品种的过氧化物酶比活力及其同工酶的差异。种子过氧化物酶比活力的大小及其pI10.3酶带颜色的深浅与品种的抗病性呈正相关。各品种的叶片过氧化物酶比活力及其同工酶谱的差异与品种的抗病性无明显相关。各品种的接种穗与其对照穗比较,抗病品种接种穗的过氧化物酶比活力持续上升,感病品种的酶比活力先上升后下降。抗病品种接种穗的过氧化物酶同工酶PI6.3、9.5和10.3三条酶带的颜色比对照深,感病品种的浅或消失,与品种的抗病性呈正相关。     

在叶锈菌侵染过程中小麦过氧化物酶同工酶的变化

本文研究了抗叶锈性不同的小麦品种和毒力不同的叶锈菌小种相互作用过程中过氧化物酶(POD)同工酶谱的变化。结果表明:(1)不亲和组合在接种后48小时出现新酶带3,酶带4活性明显增强,120小时后又出现新酶带9。但亲和组合没有新酶带出现,而在接种后96小时酶带4活性也明显增强;(2)慢锈品种在接种后120小时以前,酶带4活性稍有增强,在120小时后其活性骤然增强。这可能是慢锈品种的特点。如果这些特点在更多的品种上得到验证,则POD同工酶谱分析有可能作为鉴定品种抗叶锈性和区分感病或慢锈品种的一种生理生化指标。     

TMV侵染不同抗性番茄品种之后引起的过氧化物酶活性及同工酶的变化

 本文论述了不同抗性番茄品种在接种了TMV之后体内过氧化物酶及其同工酶的变化趋势。不同品种番茄幼苗接种TMV之后30天内病毒含量、过氧化物酶活性及其同工酶的测定结果表明:所有接种的番茄幼苗与健株对照相比均表现酶活性的增强及酶带数目的增多;但不同抗性品种,酶活性交化曲线及同工酶谱带的变化趋势有所不同:感性品种北京早红(+/+)及耐病品种强力米寿接种TMV之后,病毒含量迅速上升,在第15天达到最高峰,同时植株开始显症,其酶活性曲线呈现出1个增值高峰,即酶活性只在显症之后迅速上升于第24天达到最高峰,病株在症状发展过程中产生2条健株所没有的具高迁移率的同工酶谱带A与B。抗性品种Tm-2(Tm-2/+)抑制TMV在体内的增殖,在接种之后30天内植株不表现典型外部症状,其酶活性曲线具有2个增酶高峰,即在接种后第12天达到最高峰,并在第21天有1个新的高峰;在酶活性高峰期,接种植株也产生同工酶谱A与B,与感性品种不同的是谱带A与B形成较早,同时,抗性品种还产生感病品种所没有的1条同工酶谱带F。上述过氧化物酶活性及同工酶的变化趋势可以成为鉴定品种抗性一个有价值的生化指标。     

Breakdown of potato virus X resistance gene NX: selection of a group four strain from strain group three

Isolate DX of potato virus X (PVX) caused the typical reactions of a group three strain, systemic top necrosis in presence of potato hypersensitivity gene Nx and mosaic with gene Nb. When tubers harvested from DX-infected plants of the Nx: Nb cultivars Maris Piper and Pentland Dell were, grown on, most progeny plants were healthy, but some had systemic top necrosis caused by DX while others had mosaic symptoms in upper leaves and severe necrosis in lower ones. Infective sap from the plants with mosaic and necrosis always caused similar symptoms when inoculated to Pentland Dell. Only group four PVX strains can cause systemic infection without top necrosis in Nx:Nb cultivars, so the affected plants all contained a group four strain. That the severe necrosis of their lower leaves resulted from a shock reaction rather than from isolate DX also being present was indicated because the plants partially recovered, inoculations from near to the dilution end-point failed to demonstrate any separation of strains and behaviour on back-testing to Pentland Dell was unchanged after passage twice through tubers of this cultivar. Also, although DX caused severe necrotic symptoms in tubers of both Nx: Nb cultivars, these symptoms did not develop in tubers of plants with mosaic and necrosis. When cultured serially in Nicotiana glutinosa , the group four strain eventually reverted to group three.     

番木瓜花斑叶病对叶子光合作用和蒸腾作用的影响

 番木瓜叶子罹致花斑叶病,其分离叶绿体的二阶导数吸收光谱的较长波长吸收峰687、698、702毫微米和叶绿素b的85毫微米吸收峰显著消减。表明花斑叶病的侵染引起叶绿素库色素成分的变化。在相同的叶绿素含量基础上,罹病叶子所分离叶绿体的光系统Ⅱ荧光发射强度较健康叶子的低10.6%。花斑叶病的侵染降低叶绿素所吸收光的激发能的传递和利用效率。罹病叶子的光合速率为8.96微克分子·米^-2·秒^-1,仅相当于健康叶子的56.2%;叶子的CO₂传导率为健康叶子的39.5%;细胞间的CO₂浓度较健康叶子低15%。罹病叶子的蒸腾作用的速率和水分传导率较健康叶子的低。叶子罹致花斑叶病引起叶子物理特性的变化。     

Virus-induced changes in the response of faba bean to infection by Botrytis

Prior infection of faba bean with the viruses bean yellow mosaic and bean leaf roll increased host susceptibility to subsequent infection by Botrytis fabae and B. cinerea. Cell necrosis beneath inoculum droplets, rate and extent of lesion spread and sporulation of B. fabae were all increased on detached leaves from virus-infected compared with healthy plants. Changes were most marked in young leaves showing conspicuous symptoms of systemic virus infection and in plants virus-infected for at least 2-4 weeks. Localized lesions produced by B. cinerea or a low concentration of B. fabae conidia (10³ spores/ ml) showed increased cell necrosis but were not transformed into aggressive, spreading lesions on virus-infected leaves.     

西瓜花叶病毒(WMV-2)两株系寄主的病生理研究

 以沈阳农大植保系植物病毒研究室提供的WMV-2两株系WMV-2(1)和WMV-2(2)为试材,它们除寄主范围及在某示植物上有症状反应的差异外,亦导致其寄主的病生理反应不同。如接种到西葫芦叶片后,株系的强弱差别亦能反应到叶片叶绿素含量多少。光合作用强度、电导率及过氧化物同工酶活性等指标上,试验初步观察到WMV-2的两个株系其寄主病生理上,存在某些可以分辨的差异,WMV-2(1)对西葫芦叶片内叶绿素的破坏程度、降低光合强度以及过氧化物酶活性升高的程度等均大于WMV-2(2)。由此,作者等初步认为这些病生理指标可作为区分西瓜花叶病毒株系较好的辅助手段。     

Testing of Imported Potato Genotypes for Potato Spindle Tuber Viroid with a Tomato-intermediate /Electrophoresis Combined Method

The polyacrylamide gel electrophoresis (PAGE) test of Morris & Smith (1977) was evaluated for detection of potato spindle tuber viroid (PSTV) in breeding material. Number, density and mobility of nucleic acid bands in the electropherograms were influenced by genotype and growing temperature. So direct testing of genotypes was not reliable. After an intermediate viroid multiplication in tomato host plants at about 30oC and high irradiance, PSTV was reliably detectable with PAGE in inocula of potato samples of diverse origin. A 4-week incubation period proved to be suitable for inocula with low and high concentrations of a mild strain of PSTV (m-PSTV) as well as a severe strain of PSTV (s-PSTV). If incidence of PSTV is expected to be low, testing can be speeded up by bulking samples. With the combined tomato-intermediate/ PAGE assay, one m-PSTV or one s-PSTV infected leaf disk in 200 healthy ones was consistently detectable. Occasionally gels with a nucleic acid band of about the same relative mobility as the viroid band were found. Evidence that these bands were not caused by viroid is presented. A procedure to resolve such questionable test results is described. Infectivity of s-PSTV was higher than that of m-PSTV. Concentration of viroids in the inoculum influenced appearance of mild or severe symptoms and the rate of symptom production.     

木麻黄丛枝病过氧化物酶同工酶的初步研究

 利用聚丙烯酰胺凝胶电泳研究了木麻黄丛枝病健、病株以及各病级间过氧化物酶同工酶的变化.测定的结果,健株的过氧化物酶同工酶的活性比病株的要强;酶带数多2-6条.病级间过氧化物酶同工酶的变化与植株外部表现的症状相反,即病情越重,酶活性和带数则越小.因此植株的同工酶变化可看作植株内部的"生化症状",并可用作木麻黄丛枝病、健以及发病程度的简单而有效的鉴定方法.     

卫星RNA作为黄瓜花叶病毒的生防因子——Ⅲ.含有卫星RNA的黄瓜花叶病毒S51的某些生物学特性的研究

 1982~1983年比较了含有卫星RNA的黄瓜花叶病毒(CMV)S51和CMV分离物的寄主范围、症状反应和蚜虫传染的特性。对属于8科25种以蔬菜为主的植物的接种和回接实验证明:S51比CMV的寄主范围窄得多,只侵染茄科、葫芦科和藜科中的10种植物,CMV侵染6科的20种植物。S51除在西葫芦的部分植株上有花叶症状外,均无症状;而CMV能引起重花叶、畸形和坏死等症状。桃蚜对S51的传染效率比CMV低,潜育期延长2~6天。     

感染花生条纹病毒(PStV)后花生生理生化性状变化的研究

 研究表明,花生接种条纹病毒发病后叶片的光合强度、叶绿素含量及超氧化物歧化酶(SOD)活性明显下降,而过氧化物酶(POD)活性却显著提高。高感花生品种白沙1016上述指标的变化幅度较大,发病植株叶片中POD同功酶出现了4条健株中没有的新带,迁移率分别为0.67、0.73、0.80和0.89,而原有的迁移率为0.38的1条谱带变弱消失,发病后SOD同功酶谱带数没有显著变化。     

香蕉束顶病毒(BBTV)侵染对寄主内源激素的影响

 本试验用ELISA方法测定了香蕉感染束顶病毒(BBTV)后植株体内的3种内源激素,赤霉素(GA₃)、玉米素类(iPAs)和脱落酸(ABA)的变化。结果表明,感株的GA₃水平在侵染过程中虽有微弱增加,但含量和增长速度显著低于健株对照;iPAs在接种BBTV第14天后明显下降,并维持较低水平;ABA在BBTV侵染后被大量诱导增加并不断积累,在接种后第35天测定含量最高,为对照的3.34倍。试验还同时检测了BBTV在侵染过程中的运转。用间接ELISA测定的接种叶和顶叶的BBTV含量显示:接种21天后BBTV在接种叶和顶叶中还大量增殖,呈系统性分布。但寄主的症状在接种35天后才逐渐在顶叶表现。以上结果表明:香蕉束顶病的症状表现似乎主要与病株中的内源激素的失调有关,而与BBTV在体内的运转并不直接相关     

Involvement of Beet western yellows virus, Cauliflower mosaic virus, and Turnip mosaic virus in Internal Disorders of Stored White Cabbage

ABSTRACT Experiments over two growing seasons clearly showed that Turnip mosaic virus (TuMV) infection was associated with internal necrosis (sunken necrotic spots 5 to 10 mm in diameter) and Beet western yellows virus (BWYV) infection was associated with collapse of leaf tissue at the margins (tipburn) in heads of stored white cabbage (Brassica oleracea var. capitata). Virtually no tipburn was seen in cv. Polinius, whereas cv. Impala was affected severely. Internal necrotic spots were seen in both cultivars. BWYV appeared to interact with TuMV. Plants infected with both viruses showed a lower incidence of external symptoms and had less internal necrosis than plants infected with TuMV alone. Cauliflower mosaic virus (CaMV) did not induce significant amounts of internal necrosis or tipburn, but did, in most cases, exacerbate symptoms caused by TuMV and BWYV. BWYV-induced tipburn worsened significantly during storage. Post-transplanting inoculation with TuMV induced more internal necrosis than pre-transplant inoculation. There was a significant association between detection of TuMV just prior to harvest and subsequent development of internal necrotic spots. Individually, all three viruses significantly reduced the yield of cv. Polinius, whereas only BWYV and CaMV treatments reduced the yield of cv. Impala.