小麦黄矮病毒(BYDV)主流株系GPV的鉴定及其提纯研究

经测试结果,小麦黄矮病毒(BYDV)主流株系为麦二岔蚜禾谷缢蚜株系(GPV),普遍分布于我国北方中熟冬麦区、晚熟冬麦区和春麦区;以麦二岔蚜的传播能力最强。由麦二岔蚜优势介体所传播的主流株系GPV,曾导致该病多次大面积流行成灾。并对GPV株系毒源进行了提纯;对其提纯方法有所改进和简化。     

Purification, Concentration, and Inactivation of Venezuelan Equine Encephalitis Virus

Venezuelan equine encephalitis (VEE) virus was purified and concentrated by chromatography of tissue culture supernatant fluids on diethylaminoethyl-cellulose columns. Stepwise gradient elution studies indicated a broad elution pattern for the virus, with recovery occurring from 0.05 to 0.7 m NaCl. Optical density, infectivity, hemagglutination (HA), and complement fixation (CF) assays indicated that complete recovery of input virus in highly purified form was possible. Single-step elution with 0.7 m tris(hydroxymethyl)aminomethane-succinate-salt buffer resulted in a virus volume decrease of 85% with a concomitant increase in infectivity and antigenicity. Recoveries consistently equaled or exceeded 100% of the input preparations. Additional purification of column-recovered virus was obtained by sedimentation of pooled virus eluates on 50% sucrose cushions. Exposure of borate saline and 0.5% histidine suspensions of purified VEE virus preparations to 6 x 10(6) r of gamma radiation resulted in a loss of infectivity for tissue culture and a loss of lethality for weanling and suckling mice. Inactivation was an exponential function of the dosage. In contrast to infectivity, antigencity (HA and CF) of both saline and histidine preparations was retained after irradiation with doses as high as 6 x 10(6) r. Purified and irradiated VEE virus preparations have been successfully used for routine serological tests and are being evaluated as vaccines.     

Concentration and Purification of Influenza Virus on Insoluble Polyelectrolytes

A method for rapid concentration and purification of influenza virus by adsorption on and elution from an insoluble polyelectrolyte is described. To accomplish this task, influenza virus had to be rendered stable at pH 4 to 5, since viruses adsorb to the polyelectrolyte more efficiently at this pH range. A precipitate which forms in influenza harvests under acid conditions in the cold can be removed by ammonium sulfate at a concentration which traps the precipitate but not the virus. Thus, ammonium sulfate-treated influenza virus in allantoic fluid could be readily concentrated on the polyelectrolyte. Elution yielded a virus concentrate essentially free of nonviral proteins.     

应用免疫电镜技术快速检测菜豆黄花叶病毒、马铃薯M病毒和燕麦花叶病毒

应用免疫吸附电流技术(ISEM)可有效地检测腐汁液中的菜豆黄花叶病毒(BYMV)、马铃薯M病毒(PVM)和燕麦花叶病毒(OMV)。BYMV,PVM和OMV三种抗血清的适宜工作浓度和对铜网的适宜包被时间均为1000倍和1小时,对同源病毒的适宜捕获时间分别为4℃下2、2和8小时。PVM和OMV的病汁液检测灵敏度均为稀释4000倍,而BYMV病汁液稀释16000倍时还能检测到少量病毒料子。ISEM捕获法和修饰法的结果表明,这三种病毒之间无血清学交叉反应。     

The Effects of a Virus Inhibitor, NS-83, Derived from Plants, on Virus Infection and Multiplication in Tobacco

Abstract The virus inhibitor NS. 83. when spraved onto tobacco seedlings. was ettective against mechanical inoculation of TMV when applied to the inoculated surface and when mixed with the virus before inoculation. When aphids were ased to transmit potato virus before spraving inosulated seedlings immediately after the intection feed decreased the number intecteé with the virus.
Like salicylic acid. when NS-83 was injected into tobacco leaves lesion number, virus concen tration and lesion spread were decreased and pathogenesis related PR la protein associated with resisttance to plant pathogens was induced.
Zusammenfassung Die Einflüsse eines aus Pflanzen gewonnenen Virusinhibitors. NS-83, auf Virusinfektion und -verinehrung in Tabakpflanzen
Nach einer Spritzhehandlung von Tabaksämängen war der Virusinhibitor NS-83 wirksam gegen die schen mecbaniscb mit TMN inokulierte Oberfläche und auch. Wenn des Inhabitor mit dem Virus vor der laokulation gemischt wurde. Bei der Anwendung von Blattlausen. Um das Potato Virus Y zu übertragen, reduzierte eine Spritzbehandlung der Pllanzen mit NS-83 unnittelbar nach der Futteruogsintektion die Anzabl von betallenen ptlanzen.
Älmlich wie Saheylsaure bewirkre NS-83 nach dem Inizieren in Tabakblättern eine Reduzierung der Lästonenzahi der Viruskonzemration sowie der Lastionenausbreitung außerdem wurde eine Induktion des mit der Pathogenese gehoppelten Prla-Proteines, das mit der Resistenz gegeniber Pflanzenpathogenen assozuert ist. hervorgeruten.     

Rhizobium Attachment and Curling in Asparagus, Rice and Oat Plants

Observations by scanning electron microscopy revealed that rhizobiaattach to the surface of rice protoplasts with regenerated cellwalls, isolated mesophyll cells of asparagus, and root hairsof rice and oat seedlings. Those strains of rhizobia, namelyRhizobium leguminosarum biovar trifolii, Bradyrhizobium japonicumand Bradyrhizobium sp., attach to the cells of these monocotsin the same manner as they attach to the host dicots tested.Escherichia coli did not attach. These results suggest thatthe attachment of rhizobia is not a host-specific process. Whenoat seedlings were infected by R. l. trifolii, hair curlingwas observed. The interactions between monocot plants and rhizobiais discussed in this paper. (Received June 12, 1989; Accepted November 9, 1989)     

The Effects of Temperature on the Susceptibility of Potato Plants to Infection and Accumulation of Potato Leafroll Virus

Temperature both before and after aphid inoculation with potato leafroll virus (PLRV) greatly influenced the susceptibility of potato plants to infection and virus accumulation, as evaluated with ELISA using cultivars with different ratings for the resistance to PLRV. Pre-incubation at 15 compared to 27 °C increased the susceptibility of plants to infection and a subsequent PLRV accumulation. The virus was detected by ELISA in a greater proportion of plants and reached a higher concentration, when the plants were kept at 27 than at 15 °C after inoculation. The mean ELISA values obtained with PLRV-infected plants in the 15/27 combination of the pre-/post-inoculation temperatures over the period 1—6 wks after inoculation were significantly higher than those in the 27/27, 15/15 and 27/15 treatments, and the values obtained in the 27/27 treatment were significantly higher than those in the 15/15 and 27/15 ones. A hypersensitive-like intolerance reaction to PLRV occurred in the resistant cv. Irga only in the plants kept at 27 °C after inoculation.     

Effects of a Daily Short-Term Temperature Drop on Chilling-Sensitive and Cold-Resistant Plants

Russian Journal of Plant Physiology - A set of physiological and biochemical parameters (leaf growth rate, plant biomass, chlorophyll content, rates of photosynthesis and transpiration, relative...     

ELISA Detection of Odontoglossum Ringspot Virus in Mature Plants and Protocorms of Cymbidium Orchids: Potential Solutions to Problems of Sample Preparation Time and Low Virus Concentration

The ability to detect Odontoglossum ringspot virus (ORSV) released from the cut surfaces of leaf discs by ELISA was examined. Results indicate that ORSV from leaf discs can be detected but that multiple discs are necessary to obtain reliable detection of low virus concentrations, ELISA of Cymbidium protocorms, known from immunosorbent electron microscopy to be infected with ORSV, frequently produced A₄₃₅ values which would be considered either negative or marginally positive on the basis of commonly accepted statistical limits (i, e. 2 x mean, or mean + 3 x standard deviation). The comparison of paired samples, one of which had been pretteated with ORSV antiserum, improved the sensitivity of the test from 10 ng ml ‘’ of virus to 2 ng ml’.     

Effect of Light Intensity, Carbon Dioxide Concentration, and Leaf Temperature on Gas Exchange of Spray Carnation Plants

The rates of CO₂ assimilation by potted spray carnation plants(cv. Cerise Royalette) were determined over a wide range oflight intensities (45–450 W m^–2 PAR), CO₂ concentrations(200–3100 vpm), and leaf temperatures (5–35 °C).Assimilation rates varied with these factors in a way similarto the response of single leaves of other temperate crops, althoughthe absolute values were lower. The optimal temperature forCO₂ assimilation was between 5 and 10 °C at 45 W m^–2PAR but it increased progressively with increasing light intensityand CO₂ concentration up to 27 °C at 450 W m^–2 PARand 3100 vpm CO₂ as expressed by the equation TOpt = –6.47-h 2.336 In G + 0.031951 where C is CO₂ concentration in vpmand I is photo-synthetically active radiation in W m^–2.CO₂ enrichment also increased stomatal resistance, especiallyat high light intensities. The influence of these results on optimalization of temperaturesand CO₂ concentrations for carnation crops subjected to dailylight variation, and the discrepancy between optimal temperaturesfor growth and net photosynthesis, are discussed briefly     

Genetic Diversity and Evolution of Satellite RNAs Associated with the Bamboo Mosaic Virus

Satellite RNAs (satRNAs) are subviral agents that depend on cognate helper viruses for genome replication and encapsidation. Their negative impacts on helper viruses have been exploited to control plant viral diseases. SatBaMV is a commonly found satRNA associated with Bamboo mosaic virus (BaMV) that infects diverse bamboo species in the field. To investigate the genetic diversity and evolution of satRNAs, we examined seven satBaMV populations derived from five bamboo species and cultivars from Taiwan, China, and India and one from the greenhouse. We found 3 distinct clades among the seven populations. Clade I is consisted of all satBaMV isolates, except for those from Dendrocalamus latiflorus in Taiwan and Bambusa vulgaris in India, which belong to Clades II and III, respectively. Interestingly, nucleotide diversity was lower for Clade I than II and III. However, the nucleotide diversity did not seem to depend on bamboo species or geographic location. Our population genetic analyses revealed the presence of excessive low-frequency polymorphic sites, which suggests that the satBaMV population was under purifying selection and/or population expansion. Further analysis of P20, the only satBaMV gene that encodes a non-structural protein involved in the long-distance movement of satBaMV, showed evidence of purifying selection. Taken together, our results suggest that purifying selection against defective P20 protein is responsible at least in part for the evolution of the satBaMV genome.     

Effects of Temperature and Photoperiod on Assimilate Partitioning in Potato Plants

The effects of temperature and photoperiod on d. wt partitioningand ¹⁴C translocation were studied in three potato varieties.High temperatures and long days enhanced plant growth in termsof plant height and number of leaves, and also affected d. wtpartitioning between the plant organs. However, no temperatureeffect was noted on total plant d. wt, nor on the export of¹⁴C from the source leaf. Translocation of ¹⁴C to the vegetativeorgans (leaves and stems) was greater at higher temperatures,while translocation to the tubers was less under these conditions.We suggest that, under the temperature regimes studied, themain effect of high temperature is on assimilate partitioningand not on total plant productivity. Differences in responseto high temperatures were observed among varieties, with Norchipshowing the least and Up-to-Date showing the most sensitivity. High temperature, partitioning of assimilates, ¹⁴C-translocation, potato, Solanum tuberosum var. Desirèe, Solanum tuberosum var. Norchip, Solanum tuberosum var. Up-to-Date     

采用柱层析法提纯狂犬病毒的研究

采用柱层析法提纯狂犬病毒的研究顾鸣,邵益斌,顾勤,曾蓉芳（卫生部上海生物制品研究所,上海２０００５１）关键词狂犬病毒,柱层析法迄今,分离提纯包膜病毒的方法多采用密度梯度离心法、亲和层析法和等电聚焦法等,这些方法有一定的优点,但用在处理量很大的病毒疫苗...     

生物过滤床净化含乙苯废气的温度影响分析

以两种陶粒作为生物过滤床的填料净化含乙苯废气。主要考察温度变化对生物过滤塔净化含乙苯废气效果的影响。在稳态条件下,在温度为15~25℃时,乙苯的去除效率随运行温度的升高而升高,在25~45℃时,乙苯的去除效率随温度升高而降低。并通过实验得出了温度系数。结果表明,对于零级反应,温度对高入口体积负荷的影响较低入口体积负荷的影响大,而对于一级反应,则出现了相反的结果。同时也表明不同填料对温度系数的影响不显著。     

营养液温度和溶解氧浓度对黄瓜植株氮化合物含量的影响

常液温(25℃)下,当将营养液的溶解氧浓度(DO)降到1～2 mg/L时,黄瓜植株体内氮素代谢增强,根组织内各种氮素化合物含量有提高的趋势,叶和根内各种氨基酸含量显著提高,植株生长良好,对生长介质中的低氧逆境表现出较高的耐性;但高液温(33℃)下低溶解氧浓度(1 mg/L)处理,除植株可溶性氮和根组织内硝态氮含量不受影响外,叶和根中的其他各种氮素化合物含量均明显降低,而根组织内氨基酸含量则明显提高,植株生长不良,表明高液温下黄瓜植株耐低氧性明显降低.     

Effects of Temperature and CO2 Concentration on Induction of Carbonic Anhydrase and Changes in Efficiency of Photosynthesis in Chlorella vulgaris 11h

The increase in carbonic anhydrase (CA) activity and the decreasein apparent K_m(CO₂) for photosynthesis induced by reducing CO₂concentration during the growth of Chlorella vulgaris 11h cellswere followed under different temperatures. Both changes wereaccelerated by raising the temperature and reached an optimumat 32–37?C. When the CO₂ concentration was lowered from3 to 0.04%, the rate of photosynthetic O₂ evolution at limitingCO₂ concentrations increased and reached a stationary levelafter 3 h. Under such conditions, the concentration of CO₂ dissolvedin the algal suspension decreased logarithmically (t_1/2=10 min)and reached a concentration in equilibrium with 0.04% CO₂ inair after ca. 2 h. When high-CO₂ cells grown with 3% CO₂ in air were transferredto various lower CO₂ concentrations, CA activity and apparentK_m(CO₂) for photosynthesis changed depending on the CO₂ concentration.The CO₂ concentration which gives one-half the maximum valuefor K_m(CO₂) and one-half minimum value foi CA activities wasabout 0.5%. The inverse relationship observed for the changesin CA activity and the affinity for CO₂ in photosynthesis supportsthe theory that CA loweres the apparent K_m(CO₂) for photosynthesisin Chlorella vulgaris 11h. (Received August 27, 1984; Accepted February 8, 1985)