bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epidemiologische Untersuchungen bei der Wurzelhals‐ und Stengelfäule des Rapses, verursacht durch Phoma lingam
Authors: Krüger W. , Wittern F. 
Published: May 2008

Abstract Epidemiological investigations in the root and collar rot of oil seed rape, caused by Phoma lingam In this part of investigations on Phoma lingam (Tode ex. Fr.) Desm., epidemiological experiments were carried out on infection rates of oil seed rape and the fungus spectrum present during the vegetation period as well as on spore dispersal of Leptosphaeria maculans (Desm.) Ces. Et de Not.), the sexual stager of p. lingam.The infection at the stalk base can take place in autumn and about 10 to 40% were found to have P. lingam inside the tissue with higher inoculum potential P. lingam was more frequently isolated at the connection points of the lower leave than at the height of the soil level.The fungus spectrum and the frequency of the fungi isolated changed in course of the vegetation period. Whilst P. lingam and F. tabacinum increased and were isolated at high numbers, Alternaria spp. And P. eupyrena were found less at the beginning and at the end of the season. Two to three other species and further three to four were isolated at low level respectively occurred less common. The pathogenic importance of some of these species is not yet determined.The low level of leaf infection occurring in the federal Republic of Germany may have several reasons as e.g. the short phase of ascospore ejection and the low temperature in November and December. Furthermore, deep ploughing early in autumn for wheat sowing decreased inoculum potential as could be observed in sore catches obtained in several years.The development of the perithecia and the beginning of sport discharge was dependent on the rain fall. Generally, spore flight started a few hours after the rain fall began, but sometimes a high relative humidity seemed to be sufficient to initiate spore discharge. There was the tendency of spores been more discharged at slight winds (2–3) and consequently, because of winds being slightly stronger in the afternoon and evening, spores were more found in these daytimes.
Zur Verwendung von 2‐Hydroxyethyl‐Methacrylat (GMA) als Einbettungsmedium bei histologischen Untersuchungen in der Phytopathologie
Authors: Grunewaldt‐Stöcker Gisela 
Published: May 2008

AbstractThe use of 2‐hydroxyethyl‐methacrylate (GMA) as embedding medium for histological investigations in phytopathologyA new plastic embedding technique is described for subsequent thin sectioning of plant tissues. In comparison to the paraffinmethod the GMA polymerization system is less time consuming. The excellent preservation of well‐fixed tissue is fully asserted, as the embedding medium is not removed from the sections. In lightmicroscopic studies convincing results were obtained with different staining procedures; specific evidence for polysaccharides, pectine and nucleic acids was carried out with thin sections of 2‐8 μm thickness, also by fluorescence microscopy. The GMA‐embedding technique seems to be of value for various histological investigations in phytopathology.
Hyperparasitism of Puccinia horiana and other Microcyclic Rusts
Authors: Srivastava A. K. , Défago G. , Kern H. 
Published: May 2008

Abstract Verticillium lecanii and Aphanocladium album infected in 5 days 90–95 % of the teliospores of Puccinia horiana, the major pathogen of Chrysanthemum. This suggests the possibility to expand the use of V. lecanii, a commercial biocontrol agent against aphids, in order to control P. horiana, V. lecanii and A. album parasitized other microcyclic rusts but with a lesser frequency: P. dianthi (82 and 88 %), P. malvacearum (72 and 60 %) and P. glomerata (57 and 61 %). Cladosporium sphaerospermum and C. uredinicola were less effective than V. lecanii and A. album against all rust species tested.
Differentiation of Physiologic Races of the Rice Blast Fungus, Pyricularia oryzae Cav. by PAGE‐electrophoresis
Authors: Park W. M. , Lee Y. S. , Wolf G. , Heitefuss R. 
Published: May 2008

AbstractEighty‐three isolates of the rice blast fungus (Pyricularia oryzae) were tested with respect to genetic diversity and the possibility of race differentiation by electrophoresis. The fungus was genetically very heterogeneous. The isolates were differentiated into 6 races by pathogenicity on race differential varieties. There was little correlation between pathogenicity and zymogram types of one particular enzyme such as esterase, phosphatase or catalase. The isolates were divided into 14 groups by the combination of the zymogram types of the three enzymes. The isolates in the same group showed similar pathogenicity. A new method is proposed which differentiates the blast fungus races by the combination of zymogram type of enzymes. The details, are discussed.
Untersuchungen zum Einflufß von Aluminiumfosetyl auf den pflanzlichen Phenolstoffwechsel in den Pathogen‐Wirt‐Beziehungen Phytophtbora fragariae – Erdbeere und Bretmia lactucae ‐ Salat
Authors: Dercks W. , Buchenauer H. 
Published: May 2008

Abstract Investigations on the influence of aluminium ethyl phosphite on the plant phenolic metabolism in the pathogen‐host‐interactions Phytophthora fragariae ‐ strawberry and Bremia lactucae ‐ lettuce Aluminium ethyl phosphite exhibited pronounced preventive and very good curative activities. In strawberries, 4000 ppm of the compound affected an eminent protection against Phytophthora fragariae after root and leaf applications; the earlier the fungicide treatment was carried out, the more distinct was the control effect. Similar relations were established in the pathogen‐host‐interaction Bremia lactucae, in which 5000 ppm of the fungicide proved to be highly active following pre‐ and postinfectional applications.In both parasite‐host‐interactions, an enrichment of phenolics in consequence of a de‐novo‐synthesis in diseased plant tissue was observed only very late and exclusively, when fungicide and parasite had come together; inoculation on one hand or fungicide treatment on the other resulted in no remarkable effect.With great certainty, however, the augmentation of phenolics was not the cause, but rather the consequence of fungicidal efficiency which resulted in killing of the fungus and partial destruction of host tissue after direct influence of aluminium ethyl phosphite on the parasite itself. A clear proof for a main and causal evidence of aluminium ethyl phosphite‐induced phenolics for protection of strawberries against Phytophthora fragariae and of lettuce against Bremia lactucae could not be furnished.
Effects of Leaf Age, Inoculum Dose and Freezing on Development of Chocolate Spot (Botrytis fabae) Lesions on Field Bean (Vicia faba) Leaves
Authors: Creighton N. F. , Bainbridge A. , Fitt B. D. L. 
Published: May 2008

Abstract Botrytis fabae spore suspensions containing c. 1, 10, 102, 103, 104, 105, or 106 spores/ml were used to inoculate 5, 17 or 30‐day‐old field bean leaves. The percentages of the leaf areas covered by, chocolate spot lesions and the percentages of the leaf areas bearing conidiophores were assessed 1, 6, 12, 14, and 19 days after inoculation. The percentage of the area covered by lesions and the percentage of the area bearing conidiophores (logit‐transformed) increased linearly with increasing spore concentration (log10‐transformed). The proportions of leaf areas covered by lesions and bearing conidiophores were both greater on 17 and 30‐day‐old leaves than on 5‐day‐old leaves. The rate of lesion growth increased with both increasing inoculum dose and increasing leaf age. Generally there was no interaction between the effects of leaf age and the effects of inoculum dose on either lesion growth or sporulation. Two days after inoculation with suspensions of either 104 or 106 spores/ml, 7‐day‐old leaves grown at 15°C were transferred to –16°C or 2.5°C or kept at 15°C for 4 days. Two days later more spores had been produced on leaves which had been frozen (–16°C) than on, leaves kept at 2.5°C.
Influence of Endotrophic Mycorrhizae on the Fusarial Wilt of Cassia tora L.
Authors: Chakravarty P. , Mishra R. R. 
Published: May 2008

AbstractThe wilting of Cassia tora caused by Fusarium oxysporum was reduced significantly when inoculated with VAM. Mycorrhizal fungi highly influenced growth stimulation of the seedlings. The population of F. oxysporum was reduced in the presence of VAM.
Purification and Properties of the Geminivirus Euphorbia Mosaic Virus
Authors: Jaramillo Sandra , Lastra Ramón 
Published: May 2008

AbstractEuphorbia mosaic virus was purified from infected plants of Nicotiana benthamiana. Highest concentrations of virus particles were found in infected plant tissue between 10–12 days after inoculation. The enzyme driselase assisted in purification of the virus particles from the infected tissue yielding about 600 μg/kg of plant material. Purified preparations showed a maximum absorption at 260–263 nm and the ratio of absorption at 260 and 280 nm was 1.4. The viral nucleic acid was digestedby DNase I and S1 Nuclease but not RNase A. A single coat protein with a MW of 32,000 d and two DNA bands with a MW 0.96 × 106 d (2870 nucleotides) and 0.90 × 106 d (2700 nucleotides) were associated with the purified virus particles. Virus specific DNA was isolated from infected tissue between 7 and 15 days after inoculations.
Antifungal Effects of Bacilysin and Fengymycin from Bacillus subtilis F‐29‐3 A Comparison with Activities of Other Bacillus Antibiotics
Authors: Loeffler Wolfgang , Tschen Johannes S.‐M. , Vanittanakom Nongnuch , Kugler Martin , Knorpp Elisabeth , Hsieh Ting‐Fang , S. M. , Wu Tene‐Gene 
Published: May 2008

AbstractOf the two antifungal antibiotics produced by Bacillus subtilis F‐29‐3, the dipeptide compound bacilysin inhibits yeasts (and bacteria), whereas the formerly unknown fengymycin, a complex of closely related lipopeptide components, shows antibiotic activity against filamentous fungi.Bacilysin production, formerly known for a few strains only, could be demonstrated for all 12 wild‐type cultures of Bacillus subtilis tested during this study. The antibiotic also occurs in some strains of three other Bacillus species considered as closely realted to B. subtilis.Members of the lipopeptide class of antifungal Bacillus metabolites were formed by 8 of 12 Bacillus subtilis‐isolates and several other Bacillus strains.The antibiotics of F‐29‐3 were compared with antifungal metabolites of other Bacillus isolates using TLC, agar‐diffusion techniques and tests demonstrating the capacity of six lipopeptide and peptide preparations to protect rice seedlings from phytomycosis due to Rhizoctonia solani.Fengymycin proved to be different from the other compounds tested. It was less toxic to the test plants and protected them better from Rhizoctonia disease than the other antibiotics of the study did.
Zum Auftreten von Phoma nigrificans (P. Karst.) comb. nov. (Teleomorph Didymella macropodii Petrak) an Winterraps (Brassica napus L. var. oleifera Metzger)
Authors: Boerema G. H. , Loerakker W. M. , Wittern I. 
Published: May 2008

Abstract On the occurrence of Phoma nigrificans (P. Karst.) comb. nov. (teleomorph Didymella macropodii Petrak) on winterrape (Brassica napus L. var. oleifera Metzger) With a screening for resistence of winterrape to Phoma lingam (teleomorph Leptosphaeria maculans), in various places in North Germany, another species of Phoma was repeatedly isolated from plants with blackleg symptoms. This Phoma species could easily be distinguished from P. lingam by its larger conidia and its lower optimal temperature. Comparative study with isolates in the Phoma‐collection of the “Plantenziektenkundige Dienst” (Wageningen) showed that it, represents the anamorph of Didymella macropodii, an Eurasian Ascomycete occurring on different wild crucifers and originally described from Macropodium nivale in Siberia. The Phoma‐anamorph of this fungus was first described in Finl, and from Armoracia rusticana as Sphaeronaema nigrificans. This binomial is now transferred to Phoma (“section Sclerophomella”). Inoculation of rape seedlings with Phoma nigrificans (Didymella macropodii) resulted, in dark discolorations and constrictions of the hypocotyls of the seedlings.
Affinity Purification of Specific Antibodies from Plant Virus Capsid Protein Immobilised on Nitrocellulose
Authors: Rybicki E. P. 
Published: May 2008

AbstractThe application of a small‐scale method for the preparation of antibodies specific for coat proteins of simple plant viruses is described. The method entails the preparative electrophoresis of crude virion extracts, electrophoretic transfer of the resolved proteins onto nitrocellulose paper, excision of a specific protein band, and the attachment and subsequent elution of antibodies specific for the excised protein. The method was tested with brome mosaic virus (BMV) and low molecular weight plantproteins. It was possible to produce antibodies from multiply‐reactive sera that reacted only with the proteins used to purify them. Antibodies eluted from BMV coat protein monomer reacted strongly with intact virus in indirect ELISA. Other possible applications of the technique to plant virology are discussed.
Transmission of Pseudomonas avenae, the Cause of Bacterial Stripe of Rice
Authors: Shakya D. D. , Chung H. S. , Vinther F. 
Published: May 2008

AbstractTransmission of Pseudomonas avenae from rice seed to seedling and from plant to seed was shown. Based on experiments with unhulled and hulled seeds and on histopathological studies the location of the pathogen in seeds and the possible pathway of the pathogen from seed to seedling is suggested. Infected seeds were harvested from plants on which no symptoms were observed after the seedling stage. The experimental conditions indicated that the bacterium can be transmitted internally from plantto seed in latently infected plants.
Enzyme Changes Associated with Host‐Parasite Interactions between Pearl Millet and Downy Mildew Fungus
Authors: Arora Y. K. , Mehta N. , Thakur D. P. , Wagle D. S. 
Published: May 2008

AbstractDuring the pathogenesis of pearl millet by the downy mildew (Sclerospora graminicola [Sacc.] Schroet.), the activities of peroxidase (PO) and indoleacetic acid oxidase (IAAO) and their isozyme pattern determined by isoelectric focusing on polyacrylamide gels, were observed in extracts of leaves and ears at different stages of development. The PO activity in extracts from infected plants of a susceptible cultivar was found to be higher than in healthy plants. The higher activity was most probably due to the acceleration of host senescence by the pathogen. Quantitative differences in the isozyme patterns of PO and IAAO were found. In inoculated plants of the resistant cultivar, no symptoms developed under the conditions used for infection of the susceptible cultivar and the changes in enzyme activities after inoculation were not significant. The results indicated that different proteins are synthesized in the two cultivars.
Fungal Antagonists of Gerlachia nivalis
Authors: Al‐Hashimi Mediha H. , Perry D. A. 
Published: May 2008

Abstract Trichoderma viride was strongly antagonistic to Gerlachia nivalis in agar plate culture and it controlled infection of barley seedlings from seed‐borne inoculum when incorporated in soil as straw culture and from soil‐borne inoculum when conidia were applied to the seed coat. Penicillium expansum and Papulaspora byssina were inhibitory towards G. nivalis in culture, although not as strongly as T. viride, and they did not control seedling infection as effectively.
A Bark Necrosis of Grapevine Caused by Pseudomonas syringae V. Hall, in Sardinia
Authors: Cugusi M. , Garau R. , Prota U. , Dore M. 
Published: May 2008

AbstractAn unusual disorder occurred on ‘Vernaccia’ vine, particularly in the typical cultivation area of the variety, in the province of Oristano. Main symptom is the decaying of wood and bark. This causes the loss of the bark on the circumference of the trunk and causes the plants to die. Degradation can develop very deep in the wood rings. Affected rings can detach from the new formed ones.The infectious process is very serious in the younger plants and can slow their evolution in the years. Furthermore it does not allow the recovery of the affected plants. In some vineyards 4 % of affected plants occur. Mortality can reach up to 20%, of the affected plants and is very high during the early years after infection.A bacterium has been constantly isolated from decaying tissues; for its morphological and physiological characters and the response to serological tests it has been included in the Pseudomonas syringae Van Hall group. Pathogenicity tests carried out on ‘Vernaccia’ vines and other varieties resulted always positive; the bacterium has always been reisolated from artificially affected areas. The latter were much diffused and, sometimes, reproduced the typical symptomatology of the disease observed in nature.
Control of Downy Mildew, Plasmopara viticola (de Bary) Berlese et de Toni, on Grapevine Leaves through Water Extracts from Composted Organic Wastes
Authors: Weltzien H. C. , Ketterer N. 
Published: May 2008

AbstractWatery extracts of composted manure‐straw‐soil mixtures induced increased resistance of grapevine leaves against downy mildew, Plasmopara viticola, if applied by dipping or spraying. The extracts had no direct fungicidal or fungitoxic effects.
Serological and Lysotypical Variability of Xanthomonas albilineans (Ashby) Dowson, Causal Agent of Sugarcane Leaf Scald Disease
Authors: Rott P. , Arnaud M. , Baudin P. 
Published: May 2008

AbstractThe serological and lysotypical properties of 28 strains of X. albilineans originating from different geographic zones were analysed. Using the indirect immunofluorescence technique with 3 anti X. albilineans immunsera, the existence of three serovars was shown. The isolation of lytic bacteriophages from the soil enabled us to classify the bacterial strains into 6 lysovars. A correspondance between serovars and lysovars was revealed. These results show a variability of the X. albilineans species, and enable an analysis of the structure of its populations to be proposed, especially that of Tropical Africa.
Investigation of a Great Number of Actinomycete Isolates on Their Antagonistic Effects Against Soil‐Borne Fungal Plant Pathogens by an Improved Method
Authors: Turhan Gülay , Grossmann F. 
Published: May 2008

AbstractBy means of a modified agar‐ring method, the antibiotic efficacy of 300 isolates of actinomycetes, obtained from soil samples from Turkey, against six different test fungi was investigated. A wide range in their degree of sensitivity was evident. Whereas Sclerotinia sclerotiorum was completely inhibited by more than 90 % of the tested isolates, Rhizoctonia solani and Alternaria alternata were suppressed by only 17 and 14 %, respectively; Pythium debaryanum, Cochliobulus sativ, us and Macrophomina phaseolina held an intermediate position. Isolates which completely prevented the growth of Rhizoctonia solani and Alternaria alternata, were usually also highly effective against the other test fungi. Possible conclusions which may be drawn from these results are discussed.
Carpogenic Germination of Sclerotia of Sclerotinia sclerotiorum after Periods of Conditioning in Soil
Authors: Phillips A. J. L. 
Published: May 2008

AbstractPeriods of conditioning in soil reduced the length of the resting period needed before sclerotia of Sclerotinia sclerotiorum could germinate to form apothecia. Curves for germination of sclerotia were fitted by a form of the log‐logistic equation and from this equation the time taken for 50% germination (x50) was calculated. These x50 values were used as the basis for comparing germinability of sclerotia collected from infected sunflower plants and others conditioned in soil, or moist vermiculite for various times. Sclerotia from sunflower roots germinated sooner than those from the stem cavities. Germinability increased with the length of the conditioning period. Conditioning in soil was more effective than in moist vermiculite.
The Search for a Specific Antigen for Erwinia amylovora
Authors: Laroche M. , Verhoyen M. 
Published: May 2008

AbstractA specific reaction has been observed in immunodiffusion, using the supernatant obtained after centrifugation of E. amylovora phenol treated cells. This reaction occurred for all the E. amylovora strains examined and could be distinguished from all other reactions occurring with different species of Erwinia. We called the product inducing the specific reaction: Specific Antigenic Fraction or SAF.The immunological and chemical characteristics of SAF have been compared with other extractable products from the bacteria (LPS, ‘O'Ag), from the culture media (EPSc) and from the ooze (EPSo). This revealed that SAF is lipopolysaccharide in nature and that the specific antigen(s) involved would be on a polysaccharidic fraction.
A Comparison of the Effects of Temperature on the Growth of Fusarium oxysporum f. sp. narcissi in Solid and Liquid Media
Authors: Linfield Christine A. 
Published: May 2008

AbstractThe effect of different temperatures on mycelial growth of Fusarium oxysporum f. sp. narcissi in liquid and on solid medium was compared. Differences between optimum and maximum temperatures using these substrates were considerable and, could lead to different interpretations of the parasitic growth of the pathogen in vascular tissues, for example, in liquid culture Fusarium grew at 45°C whereas it did not on solid media. Initially F. oxysporum f. sp. narcissi may, be encouraged to grow faster in warm air drying systems than those using lower temperatures. The rates of diffusion between 17°C and 35°C are not markedly different. The speed with which moisture is removed from the internal tissues of the remaining roots is governed more by air flow over the bulbs than by temperature.
Production of Cutin Hydrolyzing Enzymes by Botrytis cinerea in vitro
Authors: Salinas J. , Warnaar F. , Verhoeff K. 
Published: May 2008

AbstractThe production in vitro of cutin hydrolyzing enzymes by five isolates of B. cinerea was studied, using cutin of tomato fruits as a carbon source. Chemical depolymerisation of the cutin yielded 10,16‐dihydroxyhexadecanoic acid as the main component. The same fatty acid was found after incubation of cutin with a crude enzyme preparation from a culture filtrate of B. cinerea. Hydrolysis was optimal at pH 5.5–6.0. In cultures with glucose as the only carbon source no cutinase activity was detected. Crude enzyme preparations which hydrolyzed cutin, also hydrolyzed para‐nitrophenylbutyrate, with an optimum activity at pH 8. All five isolates showed para‐nitrophenylbutyrate hydrolyzing activity when grown on tomato cutin, but the activity varied with the isolate used. No correlation was found between para‐nitrophenylbutyrate‐hydrolyzing activity of an isolate and its production of small lesions on young tomato fruits.
Biological Control of Fireblight (Erwinia amylovora [Burr.] Winslow et al.) on Ornamentals
Authors: Isenbeck M. , Schulz F. A. 
Published: May 2008

AbstractSeveral yellow pigmented, rod‐shaped bacterial strains with antagonistic activity against E. amylovora had been isolated from blighted ornamental shrubs. Criteria of the mode of action have been investigated under in‐vitro conditions and in inoculation experiments. In contrast to the noninhibitory isolates of the same host origin the active forms obviously produce a substantial principle. This is active only under acid conditions, it is heat‐stabile, it can be dialyzed and is solublein water and methanol. It is not a phenolic compound.In disease control experiments using culture filtrates of the antagonistic bacterial isolates fireblight could be reduced to a limited extend following shoot tip inoculation of Cotoneaster bullatus under controlled conditions. Compared to application of the living antagonists in the control experiments disease reduction, however, was considerably less expressed.