Differences in disc gel electrophorese pattern of soluble proteins excreted by different physiological races and isolates of Cladosporium fulvum

The extracellular soluble proteins of 15 different isolates comprising 9 different physiological races ofCladosporium fulvum were harvested from 3 to 4 weeks old shake cultures. The culture filtrates were purified by gel filtration over Sephadex G-25 and the V_o-fractions were freeze-dried. These preparations were submitted to disc gel electrophoresis on polyacrylamide gels at pH 9.5 at circa 4°C. The electrophoretical protein patterns appeared to differ for each isolate irrespective of the physiological race to which they belong. The various isolates originated from different sites in the Netherlands.     

Range of phytoplasma concentrations in various plant hosts as determined by competitive polymerase chain reaction

ABSTRACT For competitive polymerase chain reaction (PCR), an internal standard DNA template was developed that consisted of a highly conserved, internally deleted 16S rDNA fragment of an aster yellows phytoplasma. The internal standard was calibrated using a quantified culture of Acholeplasma laidlawii. Serial dilutions of the internal standard and fixed amounts of target templates from infected plants were coamplified with the same primers, and the products obtained were quantified using an enzyme-linked immunosorbent assay procedure. Analysis of the data revealed that the phytoplasma concentration in the plants examined differed by a factor of about 4 x 10(6). Phytoplasma concentrations of 2.2 x 10(8) to 1.5 x 10(9) cells per g of tissue were identified in periwinkles infected with various phytoplasmas. High to moderate concentrations were detected in Malus domestica (apple) genotypes infected with the apple proliferation phytoplasma, Alnus glutinosa (alder) genotypes infected with the alder yellows phytoplasma, and most aster yellows-infected Populus (poplar) genotypes examined. Very low phytoplasma concentrations, ranging from 370 to 34,000 cells per g of tissue, were identified in proliferation-diseased apple trees on resistant rootstocks 4551 and 4608, yellows-diseased Quercus robur (oak) trees, and Carpinus betulus (hornbeam) trees. Such low concentrations, which corresponded to about 4 to 340 cells in the reaction mixture, could only be detected and quantified by nested PCR.     

Effects of picloram on shoot anatomy of red maple and white ash

The anatomy of the shoot system of red maple and white ash was examined at various times after treatment with picloram. Xylem blockage, enlargement of cortical and pith cells and eventual necrosis of the shoot apex, parenchymatous and phloem tissues of red maple plants were features shown by picloram treatment. Red maple shoots were desiccated and dead by 22 days after treatment commenced. White ash shoots showed some increased mitotic activity but at the end of 22 days of picloram treatment, the leaves were still turgid and the internal anatomy of the shoot system scarcely altered. It is suggested that the susceptibility of red maple plants can be explained in part by the effects picloram has on xylem blockage and necrosis of parenchymatous tissues in the shoot system of this species. Effects du piclorame sur l'analomie de la partie aérienne de l'erable rouge et du frêne blanc L'anatomie de la partie aérienne de l'érable rouge et du frêne blanc a été examinee i diverses dpoques aprés un traitement au piclorame. Le blocage du xyléme, le grossissement des cellules corticales et médullaires, ainsi qu'une Éventuelle nécrose des apex des tiges, des tissus parenchymateux et du phloéme des Arables rouges furent les effects consécutifs au traitement par le piclorame. La partie aérienne des Arables rouges se déssécha et mourut 22 jours aprés le dé A but du traitement. La partie aérienne du Fréne blanc manifesta un accrolssement d'activité mitotique. mais, 22 jours aprés le traitement au piclorame, les feuilles étaient encore turgesccntes et l'anatomie interne des organes aériens k peine altérte. II est suggéré que la sensibility de rérable rouge peut être expliquée en partie par les effets du piclorame sur le blocage du xyléme et les necroses des tissus parenchymateux dans les organes adriens de cette espèce. Die Wirkung von Picloram auf die Anatomic des Sprosses von Acer rubrum L. und Fraxinus americana L. Es wurde die Anatomie des Sprosssystems von Acer rubrum L. und von Fraxinus americana L. zu verschiedencn Zeiten nach einer PJilorambehandlung untersucht. Bei Acer rubrum traten als Sympiome auf: Verstopfen des Xylems, VergröBerung der Rinden-und Markzellen und schliesslich Absterben der Sprossspitze, des parenchymatischen und des Phloemgewebcs. 22 Tage nach der Behandlung waren dis Sprosse ausgelrocknet und tot. Bei Fraxinus americana zeigten die Sprosse erhohte mitotische AktivitSt, aber 22 Tage nach der Piclorambehandlung waren die Blotter noch turgeszent und der innere Auf bau des Sprols systems war kaum verSndert. Die Befunde deuten darauf hin, daβ die Empfindlichkeit von Acer rubrum gegenuber Pictoram zum Teil mit seiner Wirkung auf das Xylem und das parenchymatische Gewebe im Sproβsystem erklärt werden kann.     

Studies of the adsorption of paraquat on soluble humic fractions by gel filtration and ultrafiltration techniques

The adsorption of paraquat dichloride (1,1′-dimethyl-4,4′-bipyridylium dichloride) on a soluble sodium humate fraction of a Fenland soil was studied by gel filtration (on Sephadex G10 and G100) and by ultrafiltration (through an Amicon Diaflo UM-2 ultrafilter). Both methods depend upon the separation, on a molecular weight basis, of the unadsorbed molecules of herbicide from the adsorption complex (consisting of polymeric organic materials and the adsorbed paraquat). Separations were obtained on columns of Sephadex G10 (Method I) and in the ultrafiltration experiments (Method II), and isotherms were prepared from data for adsorption in water (by Method II) and in sodium chloride (by Methods I and II) solutions. Results from the two methods were comparable over the concentration range examined. The increased adsorption of paraquat by Na⁺-compared with Ca²⁺-humate is explained on the basis of the selectivity sequence of humate for exchangeable cations. Attempts to prepare isotherms from gel filtration data, for the adsorption of paraquat on two soluble model humic polymers (polyacrylic acid and a polymer prepared by the oxidative coupling of benzoquinone and ammonium chloride) were unsuccessful because binding to the gel matrix did not permit quantitative recoveries of the adsorption complexes. Paraquat was adsorbed to the same extent on each of four fractions of Na⁺-humate separated on Sephadex G100.     

Identification of Phytophthora species on fruit crops in Turkey by polyacrylamide gel electrophoresis1

To identify 11 Phytophthora isolates obtained from lemon, peach and apple trees, and from strawberry plants, in the Mediterranean region of Turkey, protein, acetylesterase, peroxidase and catalose band patterns of these isolates and the same bands of 10 identified isolates of Phytophthora citrophthora, P. cinnamami and P. cactarum were compared. These 11 regional isolates were identified on the basis of the similarity of their protein and enzyme band patterns to those of identified Phytophthora isolates. It was concluded that protein band patterns could be used for identification of Phytophthora species. With enzyme band patterns, however, it may be possible to identify at species level but it is more practical to use this method only for identification of subspecies.     

过氧化氢作用下东北红豆杉悬浮培养细胞中蛋白表达差异的研究

 东北红豆杉悬浮培养体系中加入一定浓度的过氧化氢,染色结果表明,过氧化氢可以诱导植物细胞发生过敏反应。应用蛋白质双向凝胶电泳技术,比较过氧化氢处理细胞与正常细胞的蛋白质组差异,分析过氧化氢对东北红豆杉细胞蛋白质表达的影响。结果表明,过氧化氢(3.5 mmol/L)处理48 h后的样品中有12个新增的差异蛋白点,而在对照中有1个特异蛋白点。这些差异蛋白可能与过氧化氢的作用及细胞发生过敏反应有关。     

Some aspects of the absorption of picloram by gorse (Ulex europaeus L.)

Plants of Ulex europaeus were grown from cuttings and studies made of the absorption of 14C-picloram applied with unlabelled 2,4,5-T. In vivo experiments in a growth chamber showed that absorption ceased after 10 h, but was resumed on wetting. In in vitro experiments the Q10 and the activation energy for uptake decreased with increasing temperature. Absorption was increased by addition of non-ionic surfactants, by lowering the pH and by removal of cuticular wax. Gorse shoots were shown to have a high wax content but scanning electron microscopy revealed no obvious wax structures and the contact angle of spray droplets was less than 900, indicating that the surfaces were not difficult to wet.     

Identification and differentiation of Phytophthora by electrophoresis of mycelial proteins and isoenzymes1

Total proteins (both native and denatured) and three isoenzyme systems (esterases, malate dehydrogenases, superoxide dismutases) were analysed for eight Phytophthora species and for eight strains of P. nicotianae. The results obtained showed low intraspecific variability (62-100% of similarity index) for P. nicotianae and allowed the characterization of P. capsici, cinnamomi, cryptogea, megakarya, megasperma, nicotianae, palmivora and citrophthora by the polyacrylamide gel electrophoretic profiles of native proteins and isoenzymes. The interspecific variability between these eight species is high (27-49% of similarity index). The results obtained support the use of these macromolecular criteria as an aid to the identification of Phytophthora spp.     

Eastern and southern African strains of Xanthomonas campestris pv. vasculorum are distinguishable by restriction fragment length polymorphism of DNA and polyacrylamide gel electrophoresis of membrane proteins

Thirty strains of Xanthomonas campestris pv. vasculorum were examined using restriction fragment length polymorphism (RFLP) of genomic DNA and polyacrylamide gel electrophoresis (PAGE) of membrane proteins. Previous reports suggested the existence of two geographical strains of this pathogen, occurring primarily in eastern and southern Africa. Seventeen southern African strains from South Africa and Zimbabwe formed an apparent clonal population with distinct and unique RFLP patterns and membrane protein profiles. Similarly, 11 eastern African strains from Mauritius and Reunion and two from Australia were also related, indicating the possible existence of two distinct organisms separated by geographical locality but otherwise involved in the same disease. Our data confirm the long-held hypothesis that eastern African strains of X. c. pv. vasculorurn are distinct from the southern African strains. The fact that these two distinct strains cause the same disease, gumming disease of sugar cane, suggests the possible independent development of the pathogen in these two localities.     

Chromosomal composition of the genome in the monomorphic diplokaryotic microsporidium Paranosema grylli: analysis by two-dimensional pulsed-field gel electrophoresis

The molecular karyotype of Paranosema grylli Sokolova, Seleznev, Dolgikh et Issi, 1994, a monomorphic diplokaryotic microsporidium, comprises numerous bright and faint bands of nonstoichiometric staining intensity. Restriction analysis of chromosomal DNAs by "karyotype and restriction display" 2-D PFGE has demonstrated that the complexity of molecular karyotype of P. grylli is related to the pronounced length polymorphism of-homologous chromosomes. The background of this phenomenon is discussed in the context of ploidy state, reproductive strategy and population structure in this microsporidium. We propose that the remarkable size variation between homologous chromosomes in P. grylli may be a consequence of ectopic recombination at the chromosome extremities.     

飞达红可溶性粒剂防除加拿大一枝黄花的效果

于春、秋二季分别使用88.8%飞达红可溶性粒剂120~150 g/667m2,可有效控制加拿大一枝黄花的发生与危害。     

Simplified application of return gel electrophoresis for the routine detection of potato spindle tuber viroid

The return gel electrophoresis method for the detection of potato spindle tuber viroid has been modified to simplify its use for large-scale testing. The quantities of dissolvents for the extraction of nucleic acids were reduced and adapted to the use of disposable plastic tubes. The vertical electrophoresis system was replaced by a horizontal one, which was easier to handle. Migration distance for the separation of PSTV bands was shortened, saving time for the electrophoretic run. A single-buffer system was used. The detection limit was estimated as 0.3 ng per slot. It was possible to detect both mild and severe strains of PSTV.     

入侵植物牛膝菊(Galinsoga parviflora Cav.)对植物多样性的影响

采用样方法调查了呼和浩特市22个典型样地中植物的种类和数量,其中17个样地有牛膝菊的入侵,进一步分析其物种丰富度指数、优势度指数、多样性指数和均匀度指数,结果表明:22个样地中共有84种植物,隶属于28科65属,其中菊科(Compositae)植物最多(17种),占22.238%;禾本科(Gramineae)植物次之(14种),占16.667%,藜科(Chenopodiaceae)植物占7.143%;常见植物有24种。通过牛膝菊重要值与多样性指数之间关系的分析,发现牛膝菊入侵的样地与对照组CK相比,四种指数表现出基本一致的下降趋势,并且随着牛膝菊重要值的增大,Shannon-Wiener指数(H′)显著降低(P<0.05),Simpson指数(D_i)和Pielou指数(J)极显著降低(P<0.01),牛膝菊的入侵降低其分布区的植物多样性。     

Effect of concentration on the decomposition rates in soil of atrazine,linuron and picloram

The decomposition of atrazine, linuron and picloram when incubated with two soils at four levels of application was measured for periods of 3 or 4 months. The applicability of zero-order, half-order, first-order and Michaelis-Menten kinetics was considered. None of the equations described the breakdown rates adequately in spite of the apparent theoretical advantage for using an expression of the Michaelis-Menten type. In each case the rate of decomposition increased as the initial herbicide concentration decreased.     

不同类型植保无人飞机施药作业对烟草植株的影响

为规范植保无人飞机防治烟草病虫害的技术应用, 评估了植保无人飞机在烟草病虫害防治过程中对烟株的安全性, 并筛选出适合烟株生长中后期飞防施药的植保无人飞机类型及飞行方式。本试验选用目前主流的9种不同类型的植保无人飞机, 分析对比了9种植保无人飞机在烟草成熟期进行飞防作业时对烟草植株形态的影响。结果表明, 烟草植株成熟期采用四旋翼植保无人飞机以4 m或3 m 的飞行高度垂直于烟草种植垄作业对烟草的损伤较低。     

植物挥发性次生物质对植食性昆虫的影响

植物挥发性次生物质对植食性昆虫的寄主选择、取食、交配、产卵等行为有着重要的影响作用。本文就植物挥发性次生物质对植食性昆虫影响的研究状况及其进展进行综述报道,以便为进一步深入开展这方面的研究提供借鉴。     

Starch gel electrophoresis of lactate dehydrogenase and glucose phosphate isomerase of poultry coccidia using the LKB multiphor

A modification of thin-layer starch gel horizontal electrophoresis is described. The original method of Wraxall and Culliford (1986) is improved so that the preparation of starch gel is as simple as preparing the agarose gel. Thus the commercially supplied kits and instruments for the agarose gel electrophoresis can be also used for the starch gel electrophoresis. Furthermore, a method of preparing the permanent dry enzymograms from the starch gels with visualized enzymes is presented. The described procedure was used in the LDH and GPI analyses of poultry coccidia.     

飞防助剂对植保无人飞机喷施除草剂雾滴分布的影响

通过仪器分析结合田间试验方法,研究了不同飞防助剂对3种剂型除草剂沉积率、雾滴粒径、物理指标及田间药效,系统地分析飞防助剂对植保无人飞机喷施除草剂的增效作用及增效机理.结果表明,4种飞防助剂均有显著的增效作用.其中迪翔对3种除草剂的作用效果最为显著,可降低雾滴谱相对宽度至0.62,使雾滴均匀分布;增加沉积率,可最多增加3...