bluuebunny/crossref_metadata_2025_split huggingface dataset:
Leaf Spot of Mangoes Caused by Cylindrocladium scoparium in Central Brazil
Authors: Tozetto L. , Ribeiro W. R. C. 
Published: May 2008

AbstractA leaf spot disease of mango (Mangifera indica) caused by Cylindrocladium scoparium was found in central Brazil in 1994. Pathogenicity tests and re‐isolations from artificially‐inoculated leaves confirmed that C. scoparium was the incitant. This is believed to be the first report of the fungus attacking mango leaves.
Sequence Analysis of the Genomic RNA 3′‐terminal Region of a Potyvirus from Brachiaria spp. Related to Gulneagrass Mosaic Virus
Authors: Morales F. J. , Ospina M. D. , Castano M. , Calvert L. A. 
Published: May 2008

AbstractThe 3'terminal region of the genomic RNA of a potyvirus isolated from Brachiaria spp. which is related to guinea grass mosaic virus (GGMV), was compared to that of members of the sugarcane mosaic subgroup of poty viruses. Reverse transcription‐polymerase chain reaction (RT‐PCR) of total nucleic acid extracted from infected B. brizantha resulted in the amplification of a DNA product of c. 0.9 kb. This product was cloned and sequenced, it has an open reading frame of 149 amino acid residues, and a 3'untranslated region (UTR) of 474 nucleotides. Optimal alignments of the 3'UTRs of the Brachiaria potyvirus and members of the sugarcane mosaic subgroup of potyviruses showed that it has nucleotide sequence similarities of c. 42. 46, 46, and 46% to maize dwarf mosaic virus strain A, sugarcane mosaic virus strains SC and MDB, and sorghum mosaic virus strain SCH, respectively. It had higher nucleotide sequence similarities of c. 88, 89, and 92% with Johnsongrass mosaic virus (JGMV) strains MDO, MDKSl and JG, respectively. Analyses of the deduced amino acid sequence of the Brachiaria potyvirus coat protein fragment revealed a 97.3% similarity to the JG strain of JGMV to which it is scrologically related. We propose that the Brachiaria potyvirus now be considered a strain of JGMV (designated JGMV‐Brac).
Effects of Essential Oils on Phytopathogenic Fungi In Vitro*
Authors: Zambonelli A. , D'Aulerio A. Zechini , Bianchi A. , Albasini A. 
Published: May 2008

AbstractThe essential oils of Thymus vulgaris L., of Lavandula R.C. hybrid and Mentha piperita L. were tested in vitro against the pathogenic fungi Rhizoctonia solani Kühn, Pythium ultimum Trow var. ultimum, Fusarium solani (Mart.) Sacc, Colletotrichum lindemuthianum (Sacc. & Magn.) Briosi & Cav. All the oils tested inhibited fungal growth. The most effective oil was that of thyme, with a fungicidal activity attributable to thymol, found in a concentration of 50.06% in the oil tested. SEM observations revealed that these oils cause degeneration of the fungal hyphae which appeared emptied of their cytoplasmic content.
Antiviral Activity of the Glucan Lichenan (Poly‐β(l→3, 1→4)D‐anhydroglucose)
Authors: Stübler D. , Buchenauer H. 
Published: May 2008

AbstractLichenan is a linear glucan of (1→3, 1→4)‐β‐glycosidic bonds in a ratio cf 1:2 that originates from the lichen Cetraria islandica. Lichenan at 5–1000 μg/ml exhibited antiviral activity against mechanically‐transmitted viruses of different taxonomic groups. The antiviral activity was demonstrated by the inhibition of symptom development and virus accumulation in greenhouse‐grown Nicotiana tabacum (four cultivars), N. benthamiana and N. glutinosa. In plants of N. tabacum cv. “Xanthi‐nc”, which react hypersensitively in response to TMV infection, lichenan reduced the number, but not the size, of necrctic lesions both, when added to purified virions or naked viral RNA. Partly hydrolized lichenan representing different degrees of polymerization (DP) of 6–30, 30–60, 60–190, and > 190, reduced the number of local and systemic infections to the same degree as the unchanged glucan. The antiviral effect of lichenan was restricted to the leaf‐area of application. Depending on the time of application, the strongest effect was achieved when lichenan was added directly to the inoculum. Post‐infectionally, it was inhibitory only up to 3 h post‐inoculation, indicating that early events of virus replication were affected. Viral inhibition caused by lichenan results frotn a plant‐specific protection, which does not function in N. rustica.Although less inhibitory than lichenan, there were other mixed‐linkage β‐glticans (schizophylian, pacbytnan, laminaran, barley‐β‐glucan) causing antiviral effects. In contrast, pustulan as well as glucans of the a‐coniiguration (amyiose, dextran, nigeran, puUulan) were ineffective.
Antiviral Activity of the Glucan Lichenan (Poly‐β(→ 3,1 → 4)D‐anhydroglucose)
Authors: Stüobler D. , Buchenauer H. 
Published: May 2008

AbstractLichenan a β(1→ 3,1→ 4)β‐glucan exhibited a broad antiviral activity against mechanically transmitted viruses of different taxonomic groups in different Nicoliana spp. As shown for tobacco mosaic virus in vitro. lichenan did not interfere with cell‐free protein synthesis programmed with naked RNA or virus particles cotranslationally disassembled. Thus, inhibition of virus replication by lichenan is probably not attributed to direct interaction of lichenan and viral structural components, but rather to reduced sensitivity of the host tissue. Treatment of a suspension of cultured cells of Nicotiana tabacum with lichenan was accompanied by a slight increase in phenylalanine ammonia‐lyase (PAL) activity. However, lichenan applied to leaf tissue did not significantly stimulate PAL‐activity, therefore, antiviral action apparently did not depend on the induction of the phenylpropanoid pathway. According to experiments with lichenan and digitonin (used as a callose elicitor) restriction of viruses to initially‐infected cells by means of callose deposition also appears to be an improbable mechanism of viral inhibition. In cell suspensions treated with lichenan, slight changes in the extracellular concentration of free K+ were observed that did not reflect a marked K+ leakage, as caused by digitonin. This finding requires further examination. According to the present results, it is likely that lichenan affects the early virus‐cell interactions that occur after virus disassembly.
Differential Induction and Accumulation of β‐1,3‐Glucanase and Chitinase Isoforms in the Intercellular Space and Leaf Tissues of Pepper by Xanthomonas campestris pv. vesicatoria Infection
Authors: Lee Yeon Kyeong , Hwang Byung Kook 
Published: May 2008

AbstractThe virulent strain Ds 1 of Xanthomonas campestris pv. vesicatoria multiplied in pepper (cv. Hanbyul) leaves better than did the avirulent strain 81–23, which formed localized necrosis at the onset of pathogenesis. Infection of pepper leaves by X. campestris pv. vesicatoria induced the synthesis and accumulation of β‐1,3‐glucanase and chitinase in the intercellular space and leaf tissue of pepper plants. In the uninoculated controls, the two hydrolases remained at a very low level. High levels of the two enzymes were found in an incompatible interaction of pepper leaves with X. campestris pv. vesicatoria. In particular, chitinase activity in the intercellular washing fluids (IWF) was higher in the incompatible than in the compatible interactions. The direct detection of acidic β‐1,3‐glucanases on 10% native PAGE gels revealed only two isoform bands (Ga 1 and Ga 2). Isoelectric focusing identified two acidic β‐1,3‐glucanase isoforms with pl 5.0 and 5.2, and four basic isoforms with pl 7.1, 7.4, 7.9, and 8.8 in the IWF and extracts of infected leaf tissues. Some of the isoforms disappeared during pathogenesis and the others appeared during symptom expression. The acidic chitinase isoforms (Ca 1, Ca 2, and Ca 3) were located primarily in the intercellular spaces. Synthesis of high levels of the acidic isoform Ca 3 in infected pepper leaves was seen. Several basis chitinase isoforms accumulated only in diseased leaf tissue, and especially more in the incompatible than the compatible interaction. By using isoelectric focusing, the three acidic and seven basic chitinase isoforms in the IWF and leaf extracts were detected on chitin overlay gels.
Differences Between Barley, Oats and Wheat in the Occurrence of Deoxynivalenol and Other Trichothecenes in Norwegian Grain
Authors: Lanoseth W. , Elen O. 
Published: May 2008

AbstractThe amount of the Fusarium toxins deoxynivalenol (DON). 3‐acety‐DON. ivalenol and fusarenon × have been determined in about 3000 samples of barley, oats and wheat grown in Norway. The samples were collected in the period 1988–1994. and grouped according to grain species, year of production, district and sample category. The DON content was found to be significantly higher in oats than both barley and wheat in grain produced by ordinary grain producers in Norway. Of samples collected from grain silos. 68.7% of the barley. 97.1% of the oats and 66.3% of the wheat samples were found to contain 30 mg/kg of DON or more. The proportion containing 1000 μg kg or more was 2.1.13.4and0.0% in burley, oats and wheat, respectively. However, these variations in contamination level were not reflected in the results from two field trials, where the grain species were grown side‐by‐side in the same fields. The differences in contamination level between the grain species seem to be due partly to edaphic and agrotechnical factors and partly to variation in the susceptibility to different Fusarium species in interaction with climatic factors. Nivalenol(≥ 50 μg/kg) was detected in 8.3% of the barley samples. 8.2% of the oats and 0.4% of the wheat samples. Samples collected at the grain silos were then not included.
The Influence of pH on Biodeterioration of a Tropical Timber Exposed to Mixed Cultures of Biocontrol and Wood‐Rot Fungi
Authors: Ejechi B. O. , Obuekwe C. O. 
Published: May 2008

AbstractA laboratory investigation of the decay control potentials of Trichoderma viride and Penicillium sp. on the deterioration of obeche wood (Triplochiton scleroxylon). buffered at various pH. by wood‐rot fungi (Gloeophyllum sp. and Gloeophyllum sepiarium), was carried out. Biomass determinations in carboxylmethyl cellulose broth at various pH showed that the biocontrol fungal strains exployed grew better as the pH approached neutral while the reverse was true for the wood‐rot fungi. Deterioration of wood (buffered at various pH) simultaneously inoculated with the biocontrol and wood‐rot fungi was more markedly reduced towards neutral pH than at lower pH values. Decay begun in wood initially infested with rot fungi before inoculation with biocontrol fungi was virtually halted at neutral pH. which was not the case in lower pH (2 and 3) buffered wood simultanecously inoculated with biocontrol and wood‐rot fungi. A killing effect was indicated when the rot fungi failed to appear on potato–dextrose agar from interior sections of the wood blocks. Manipulation of pH may prove important in biological control of wood decay.
Suppression of Pythium Root Rot of Cucumber by a Fluorescent Pseudomonad s Related to Reduced Root Colonization by Pythium Apbanidermatum
Authors: Moulin F. , Lemanceau P. , Alaboutte C. 
Published: May 2008

AbstractRoot colonization of cucumber with P aphanidermatum OP4 was examined in the absence and in the presence of either fluorescent pseudomonad strain CH31 or strain CHI. Quantification was performed by antigen‐coated plate enzyme‐linked immunosorbent assay (ACP‐ELISA) using an antiserum obtained from a rabbit immunized with zoospore cysts: this antiserum did not cross‐react with non‐infested roots of cucumber, or with the fluorescent pseudomonads CH31 and CHI. Application of the previously developed biotest enabled us to assess the ability of the two strains of fluorescent pseudomonad to suppress root rot caused by P. aphanidermaium OP4.At all bacterial densities tested, the fluorescent pseudomonad CH31 led to a significant reduction of both the root colonization of cucumber with P aphanidermatum OP4 and the severity of Pythium root rot. In contrast, the fluorescent pseudomonad CHI had no effect on either root colonization oe disease sevenity.
A Rapid Tomato Seedling Assay for Verticillium Wilt
Authors: Madhosingh C. 
Published: May 2008

AbstractA rapid (10‐min) tomato seedling assay was developed for determining the wilt‐capacity of cell‐free culture filtrates of race 1 and race 2 isolates of Verticiilium dahliae. The assay also rapidly determined the differences in wilt resistance between tomato cultivars. Rapidity was attained by manipulating incubation conditions to promote rapid wilting. These included inducing elongated stems in the susceptible cv. Bonny Best seedlings by growth of plants in subdued light (2.2 × 102 lux) and by concentrating two‐fold the cell‐free culture filtrates of the pathogen. Further, rapid uptake of the wilt factors in the culture filtrates was facilitated during incubation by increasing transpiration with bright light (23.8 × 103 lux), a wind stream (125–150 metres/min) across the assay seedlings, low relative humidity (28%) and a relatively high assay temperature (30 C). When necessary, these conditions were altered to extend the assay times. This assay system was used to determine optimal incubation time, temperature and medium for obtaining culture filtrates with increased wilt capacities. The assay also determined the relative wilt capacities of races 1 and 2 and the comparative resistance of four tomato cultivars to wilt caused by races 1 and 2.
Identification of a Potential Source of Complete Resistance to Soilborne Wheat Mosaic Virus in a Wheat‐Thinopyrum Intermedium Addition Line
Authors: Rumajun A. , Jahter J. , Trottet M. , Lapierre H. 
Published: May 2008

AbstractSoilborne wheat mosaic virus (SBWMV) is a Furovirus transmitted by the plasmodiophoraceous fungus, Polymyxa graminis. Resistant cultivars of wheat (Triticum aestivum) to SBWMV have already been described. The resistance encountered mostly includes root infection without viral migration to foliage. In this study, the reaction of addition lines (L1, LIS, L2, L3, L4, L7), and the partial amphiploid derived from wheat (Vilmornn 27) and Thmopyrum intermedium has been evaluated. Lines L1. L3. L7. L1S and cultivar Vilmorin 27 are susceptible to SBWMV. Lines L4 and TAF 46 are root infected only. Chromosome 4Ag in L4 is thought to have an equivalent reaction to that one found in the mostly encountered resistance. Another type of resistance in a wheat line (1.2) with the added chromosome 3Agi of Th. intermedium has been characterized. In this line, L2, no SBWMV particles were detected on their roots by enzyme‐linked immunosorbent assays. Contrary to observations made on lines L1, LIS, L3, L4, L7, amphiploid TAF 46. and the wheat cultivars (Festival. Fandango, Vilmonn 27), no resting spores of P. graminis were found on roots of L2 2 months post inoculation. It is suggested that the disomic addition line L2 is immune to SBWMV.
Suppressiveness to Clubroot, Pea Root Rot and Fusarium Wilt in Swedish Soils
Authors: Worku Y. , Gerhardson B. 
Published: May 2008

AbstractNatural soil samples, collected from farms in central and southern Sweden, were tested for soil disease‐suppressiveness. The soils were mixed with inocula of either Plasmodiophora brassicae, Aphanomyces euteiches or Fusarium oxysporum. f.sp. spinaciae and disease symptoms were scored on Chinese cabbage, pea and spinach respectively, that were grown in the soil‐inocula mixture under greenhouse conditions. Most field soils limited the development of disease to some degree compared with a commercial Sphagnum‐sand‐soil mixture, and about 10% were strongly suppressive to disease outbreaks caused by either P. brassicae, A. eutheiches. or F. oxysporum f.f.sp. spinaciae. Some tested soils gave higher disease indices of A. euteiches compared with the control growing medium and were regarded disease synergistic. The suppressiveness found was specific for each disease tested and in no case was a soil sample strongly suppressive to two of the diseases tested.
Fungi Associated with Root Rot of Winter Wheat in Alabama
Authors: Chen C. , Collins D. J. , Morgan‐Jones G. 
Published: May 2008

AbstractWinter wheat plants were sampled during the spring and autumn to identify fungi associated with root rot in Alabama. Samples were taken from 61 fields in the major wheat‐producing areas of the state; 179 fungi were isolated, identified, and tested for pathogenicity. Of the fungi identified, 46 (26%) were Gaeumannomyces graminis var. tritici, 37 (21%) were Cochtiobolus sativus, and 55 (31%) were Fusarium species of which 37 (21%) were Fusarium oxysporum. Other fungi identified that were pathogenic on wheat were Rhizoctonia solani, Sderotium rolfsii, and Pythium spp. G. g. var. tritier was the main pathogen associated with diseased root and lower stem tissue of wheat in Albama.
PassifloraLatent Carlavirus in European Collections of OrnamentalPassiflora
Authors: Hicks R. G. T. , Mohamed M. E. , Blakesley D. 
Published: May 2008

AbstractPassifloralatent carlavirus (PLV) was detected by PAS‐ELISA in 15 species/hybrids or cultivars ofPassiflorawith mosaic, mottle or blotch leaf symptoms, from botanical and germplasm collections in the UK and The Netherlands surveyed in 1992 and 1993. A single lesion isolate of PLV induced leaf chlorosis in inoculated apparently virus‐freeP. caerulea. This is the first report of PLV in the UK.
Witches'Broom of Rhamnus catharticus: A New Phytoplasma Disease
Authors: Müurer R. , Seemüller E. 
Published: May 2008

AbstractA lethal witches'broom disease of buckthorn (Rhamunus catharticus) has been observed in south‐western Germany. The disease is associated with the presence of a distinct phytoplasma that is most closely related to the phytoplasmas of the apple proliferation cluster. However, the agent can clearly be distinguished from the other cluster members.
Bacterial Vascular Necrosis and Root Rot Disease of Sugar Beet in Egypt
Authors: Saleh O. I. , Huang P.‐Y. , Huang J.‐S. 
Published: May 2008

AbstractFive pectolytic bacteria were isolated from roots and petioles of sugar beet exhibiting soft rot and vascular necrosis symptoms that were collected from different fields in El‐Minia Governorate, Egypt. Inoculation of the bacteria into sugar beet roots through wounded crowns or injured lateral roots reproduced soft rot and vascular necrosis symptoms. According to their biochemical and physiological characteristics, pathogenicity tests, fatty acid composition analysis, and electron microscopy, the bacteria were identified as Erwinia carotovora ssp. betavasculorum. This is the first report of the disease in Egypt.
Transmission of Three Strains of Tobacco Streak Ilarvirus by Different Thrips Species Using Virus‐infected Pollen
Authors: Klose M. J. , Sdoodee R. , Teakle D. S. , Milne J. R. , Greber R. S. , Walter G. H. 
Published: May 2008

AbstractWhen cucumber seedlings were dusted with tobacco streak ilarvirus (TSV)‐infected pollen and infested with 5–10 thrips (adults and larvae mixed), Thrips tabaci transmitted all three Australian strains of TSV. In similar work, Microcephalothrips abdominalis transmitted both and Frankliniella schultzei one strain, respectively, of two TSV strains tested. Transmission of the Ageratum strain (TSV‐Ag) infecting pollen of Ageratum houstonianum was very efficient (100%) by all three thrips species. However, transmission rates of only 0–28% were achieved using the Ajuga strain (TSV‐A) and the strawberry strain (TSVS) in pollen of other hosts. A fourth thrips species, T. parvispinus, transmitted TSV‐Ag from infected tomato pollen to Chenopodium amaranticolor seedlings. There was, therefore, little or no vector specificity in the thrips transmission of the three strains of TSV, but factors associated with the virus‐infected pollen affected the efficiency of transmission. This is the first report of F. schultzei and T. parvispinus as vectors of TSV.
Cultural Growth Patterns and Incompatibility Reactions in Diaporthe and Phomopsis Populations
Authors: Muntan̄ola‐Cvetković M. , Vukojević J. , Mihaljčević M. 
Published: May 2008

AbstractComparative studies were carried out with cultures isolated from Phomopsis condiomata and/or Diaporthe ascomata found on naturally‐infected living stems or on overwintered stem fragments of Arctium lappa L., Helianthus annuus L., Glycine max (L.) Merr., and Xanthium italicum Moretti, growing in or nearby the same fields in Vojvodina. Results underscored the heterogeneity of the Phomopsis anamorphs in the D. arctii (Lasch) Trav, complex, Intra‐specific vegetative incompatibility groups were distinguished among Phomopsis and/or Diaporthe populations from A. lappa. More than one phytopathogenic Phomopsis and/or Diaporthe species were identified on X. italicum. P. longicolla Hobbs was isolated for the first time in Yugoslavia from soybean stem debris. The holomorph Diaporthe (Phomopsis) helianthi Muntanola‐ Cvetkovic, Mihaljcevic et Petrov showed distinguishing characteristics with respect to other congeneric fungi.
Rapid Identification of Xanthomonas campestris pv. graminis and X.c. pv. phlei by Fatty Acid Profiling
Authors: Sletten A. 
Published: May 2008

Abstract Xanthomonas campestris pv. graminis and X. campestris pv. phlei isolated from different grass‐species were analysed for their fatty acid content with a gas‐chromatograph and a commerially‐available software package. The two pathovars could be rapidly and reliably identified and separated from each other with this technique, offering alternative to time‐consuming identification by biochemical and pathogenicity tests.
Identification and Phytotoxicity of 3‐methylthiopropanoic and Trans‐3‐methylthiopropenoic Acids Produced in Culture by Xanthomonas campestris pv. vitians
Authors: Scala F. , Zoina A. , Coppola L. , Capasso R. , Lorito M. , Evidente A. 
Published: May 2008

AbstractTwo phytotoxic metabolites were isolated from culture filtrates of Xanthomonas campestris pv, vitians, the causal agent of lettuce leaf spots and headrot. The two compounds were identified as 3‐methylthiopropanoic (1) and trans‐3‐methylthiopropenoic (2) acids by chemical and spectroscopic methods. Toxic effects of the two compounds on leaf tissues and protoplasts of lettuce and cabbage were investigated. Solutions of 1 and 2 induced chlorosis and necrosis on lettuce leaves at minimum concentrations of 300 and 50 μg/ml, respectively. Infiltration in cabbage leaves did not produce any symptoms. The LD50 values for 1 and 2 against lettuce protoplasts were 15 and 16 μg/ml, respectively. Activity of the two metabolites against cabbage protoplasts was very low (LD50 > 500 μg/ml).
Fungicidal Activity of Two Spermidine Analogues
Authors: Mackintosh C. A. , Walters D. R. 
Published: May 2008

AbstractThe potential use of polyamine analogues as inhibitors of polyamine biosynthesis to control plant pathogenic fungi is well established. However, all of this information relates to the use of putrescine analogues and no data exist for spermidine analogues. In the present work, two spermidine analogues. N1‐ and N8‐acetylspermidine were evaluated against powdery mildew on barley. Post‐inoculation treatments reduced infection by 69.7% and 51.5%. respectively. Since the barley powdery mildew fungus cannot be grown axenically. mode of action studies were undertaken using the oat leaf‐stripe pathogen Pyrenophora avenae. Neither of the analogues had any effect on polyamine biosynthesis in P. avenae grown in vitro. Although the mechanism(s) by which inhibitors affect in vivo fungal growth and in vitro growth may differ, it is unlikely that the antifungal properties of the analogues are the result of a perturbation in polyamine biosynthesis.