摘要:

AbstractAntiphytoviral compounds with noncyclic azine structutreThe antiphytoviral activities of variously substituted compounds with noncylic azine structures have been studied f a total of 90 tested compunds 42 had the effect of more or less strong inhibiting the concentration of potato virus X (PVX) in inoculated and / or secondarily infected leaves ofNicotiana tabacumL. cv Samsun (Table.1) An effect on the virion of PVXin vitrocouldn't be observed (Table.2) Thus the substances may interact with the virus replication. Some of them also reduced the number of local lesions caused by tabacco mosaic virus on leaves ofNicotiana glutinosaL. (Table‐3) Several Compounds proved exellent synergists of 2,4‐ dioxohexahydro‐ 1,3,5‐ triazine (DHT = 5 azadihydrouracil; Table 4) Pyridine‐ 3‐ aldehyde S ethyl isothiosemicarbazone and the Cu complex of 1‐ ethyl‐isatine S‐ ethyl isothisosemicarbazone when used in combination with 2,4 dioxohexahydro‐ 1,3,5, triazine, greatly increased the mass of potato tubers produced from plantlets grown up from patato eye cutting as compared with the indentical control Simultaneously the mentioned substances reduced the number of symptom bearing eye cutting plants Quinoline 2‐ aldehyde‐ N‐ oxide S‐ allyl‐isothiosemicarbazone had the effect of very greatly reducing the number of symptom‐bearing plants without substantially influencing the mass of tubers (Table 5). Thus some compounds with noncyclic azine structure especially when used in combinitation with DHT, may be of high interest for practical application Comparing the structures of compounds with noncyclic azine structure active against plant or human viruses it should be noted that antiphytoviral compounds active in these two different virus host systems often a

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00483.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractThe Jordanian isolate of watermelon mosaic virus‐2 (WMV‐2Jo) was purified from infectedCucurbita pepocv. Top Capi by extraction in 0.05 M sodium citrate buffer containing 0.01 M sodium diethyl dithiocarbamate and 0.01 M cysteine hydrochloride (0.01 M D + C), clarification with chloroform and n‐butanol, sedimentation by ultracentrifugation, and rate‐zonal centrifugation in 10–40% sucrose gradient. The purified virus had an ultraviolet absorption spectrum typical of a nucleoprotein with a low nucleic acid content. Homologous antiserum had a titre of 1: 256, as determined by the ring interface test. Electron microscopy of negatively stained purified virus revealed flexuous particles with a normal length of 750 nm. Cytoplasmic spindle‐shaped inclusions were readily detectable in infected epidermal cells under the light microscope. Thin sections of infected tissue revealed the presence of laminated aggregates, pinwheel and scroll inclusions. The virus reacted with antisera prepared to the Florida strain of WMV‐2 and zucchini yellow mosaic virus in a sodium dodecyl sulfate (SDS) agar gel diffusion test. Using the Derrick‐decoration combined technique of immune electron microscopy, the virus reacted strongly with the homologous antiserum and zucchini yellow mosaic virus antiserum, but less with antiserum prepared to the Florida

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00484.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractAn inhibitor extracted form the cell walls of apple fruits suppressed the activity of endopopygalacruronases (endo‐PGs) producedin vivoandin vitrobyNectria galligena, Phomopsis mali, Fusarium LateritiumandGlomerella cingulatabut not the endo‐PGs produced byPenicillium expansumorPhytophtobora syringae.Of four apple cultivars tested Granny Smith tissue contained the highest levels of inhibitor and Cox's Orange Pippin contained the least.Linear rot expansion in the four apple cultivars inoculated withN. galligenawas inversely related to inhibitor activity in the fruit tissue, rot development being slowest in Granny Smith fruits and most rapid in Cox's Orange Pippin fruits. Rot expansion in fruits inoculated withP. expansumbore no such relationship to inhibitor activity in the tissue Apple tissue maceration by the endo‐PGs fromN. galligena, P. mali. F. lateritiumandG. cingulatawas similarly related to inhibitory activity in the fruit. The properties of the partially purified inhibitor were consistent with it being proteinaceous but the relative slowness with which it was hear inactivated and the presence of a small percentage of carbohydrate might indicate that it was a glycopr

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00485.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

RésuméL'évolution des cellules contiguës aux vaisseaux dans le xylème caulinaire de l'œillet est comparée après simple entaille (s. e.), introduction de spores deV. dahliae(iV. d.) ou deP. cinerescens(iP. c.). Tous les traumatismes expérimentaux entraînent des modifications ultrastructurales aboutissant à l'apparition de nouveaux types cellulaires. Parallèlement, les polyphénols vacuolaires sont metabolises et des vésicules “à cœur dense” apparaissent. Il s'agit là de phénomènes précoces et indépendants. Dans tous les cas, l'œillet réagit plus vigoureusement chez les iV. d.que chez les iP. c.L'étude de la gommose vasculaire révèle des differences quels que soient les critères retènus: vitesse d'installation, importance relative du phénomène, niveau de complexité structurale, chronologie d'apparition des différents constituants. Les relations éventuelles entre les structures cellulaires et les secretions gommeuses sont recherchées en comparant entre elles les situations de defense efficace (iV. d.) ou défaillante (iP. c.). Tous les elements d'analyse retenus dans ce mémoire confirment que, face a son parasite spécifique, la réponse de l'hôte est perturbée. On observe des blocages, des freinages, des déviations des voies de biosynthèse normalement mises en place par la plante en réponse à une agression fongique. Les differences de comportement de l'œillet vis‐a‐vis duVerticilliumet duPhialophoraprésentent une image de la spécificité parasitaire qui s'adapte bien au modèle récemment propose

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00486.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractThe effects of the systemically active disease control compounds Fosetyl‐Al, Metalaxyl, Propamocarb, SN 75196 and Dowco 444 on the growth,in vitroof two Oomycetes have been studied. Fosetyl‐Al, Propamocarb and SN 75196 are only weakly antifungal, and their activities,in vitroare sensitive to nutrition, pH and temperature. Factors which increase the growth of the fungus decrease its sensitivity to these compounds. These compounds display no selectivity for Oomycetesin vitrowhich belies their reported selectivityin vivo.Metalaxyl and Dowco 444 are selective for, and very active against Oomycetesin vitroand this activity could account for their modes of actionin v

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00487.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractAccording to the reaction of muskmelon line PI 414723, 22 natural isolates of Zucchini Yellow Mosaic Virus (ZYMV) were grouped into two pathotypes. When inoculated by isolates belonging to pathotype 0, most of the PI 414723 plants (over 70%) remained symptomless while few plants developed systemic chloronecrotic spotting and more rarely yellowing, stunting, mosaic and leaf deformations. When contaminated by pathotype 1 all PI 414723 plants developed systemic chloronecrotic spotting.Two variants were obtained from representative strains of these two pathotypes, able to induce yellowing, stunting, mosaic and leaf deformation on all inoculated PI 414723 plants. These variants could not be differentiated from their originating strains either by host range, serology or aphid transmission properties. Therefore they are regarded as belonging to a third group called pathotype 2. No relation was observed between the type of symptom developed on PI 414723 and the ability to induce a rapid wilting reaction of melon cv. Doublon (pathotype F).

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00488.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractAn alkali maceration technique has been developed to detect internally seed‐borne inoculum of Peronosclerospora sorghi in sorghum seeds. Optimum period for maceration was found to be 36 h. Oospores in the glumes and mycelia in the pericarp and endosperm were clearly demonstrated. Mycelium was found in the pericarp of 40 % of the seeds tested and in the endosperm of 5 % of seeds. The possibility of using this technique to detect seed‐borne downy mildew infection has been emphasi

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00489.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractAn attempt was made to investigate which factor temperature or fungal infection, has a greater effect in accelerating physiological processes such as respiration and ethylene evolution in fruit.For this study the effect of infection withTrichothecium roseum, Alternaria alternataandDiplodia natalensison banana fruit, at 14°C and 20°C was examined.The results show that the development of rot caused by different fungi and the physiological changes in the infected fruit may depend not only on the effect of temperature on fungi (asin vitro) but also on fruit ripening, or on processes connected with fruit ripening, which may accelerate fungal developmen

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00490.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Book reviewed in this article:Erb, B., und W. Matheis, Pilzmikroskopie: Präparation und Untersuchung von Pilzen.Durbin, R. D., Toxins in Plant Disease.Schlösser, E., Allgemeine Phytopathologie.Luig, Norbert, H., A Survey of Virulence Genes in Wheat Stem Rust, Pucnia graminis f. sp. tritici.Raychaudhuri, S. P., and Anupam Varma, International Journal of Tropical Plant Disease

ISSN:0931-1785    

DOI:10.1111/j.1439-0434.1984.tb00491.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY