bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the Biological Control of Phytophthora cryptogea Pethybr. et Laff. II. Effectiveness of Trichoderma and Gliocladium spp. in the Control of Phytophthora Foot Rot of Gerbera
Authors: Orlikowski L. B. 
Published: May 2008

AbstractBip T containing about 109 spores of Trichoderma viride, applied to peat 10 days before inoculation of substrate with Phytophthora cryptogea, effectively controlled Phytophthora foot rot of gerbera. The biocide in dosage of 300 and 600 g/m3 inhibited the development of the pathogen in substrate. The other potential antagonists T. hamatum and T. viride applied into peat at a dosage of 600 g/m3, decreased Phytophthora foot rot development.
The Biology of Rose Rosette Disease: A Mite‐associated Disease of Uncertain Aetiology
Authors: Epstein A. H. , Hill J. H. 
Published: May 2008

AbstractSpread of rose rosette disease was best described by a logistic population growth model. In Iowa, peak susceptibility to graft transmission of the disease in the field occurred from May 27 thrrough July 10. Populations of the eriophyid mite vector were low until mid‐July and reached peak levels at the end of August. Host range was limited to multiflora rose and hybrid ornamental roses. No evidence was obtained for seed‐or soil‐transmission of the aetiologic agent and no symptom remission was obtained with either heat therapy or tetracycline treatment. A significant decrease in stored starch corresponded with a major decrease in sucrose and increases in fructose and glucose in infected tissue. Because of its limited host range, the agent may have potential for biocontrol of multiflora rose.
Use of an Immunocapture‐Polymerase Chain Reaction Procedure for the Detection of Grapevine Virus A in Kober Stem Grooving‐Infected Grapevines
Authors: Chevalier S. , Greif C. , Clauzel J.‐M. , Walter B. , Fritsch C. 
Published: May 2008

AbstractReliable and highly sensitive detection of grapevine virus A (GVA) in grapevine leaf tissue by reverse transcription‐initiated polymerase chain reaction was achieved after enrichment and partial purification of the virus from grapevine crude sap by an immunocapture (IC) procedure. In comparison with ELISA the gain of sensitivity was estimated up to 1000‐fold in grapevine mature leaf tissue. Using IC‐reverse transcription polymerase chain reaction (IC‐RT‐PCR), GVA could be detected in very young grapevine tissue where the virus titre was largely below the detection limit of ELISA. The comparison of IC‐RT‐PCR and biological indexing results for about 60 grapevine accessions revealed a good correlation between the presence of GVA and the development of Kober stem grooving (KSG) symptoms in the specific indicator rootstock Kober 5BB. Moreover, the elimination of KSG by heat treatment in two Vitis vinifera cultivars, Savagnin rose and Servant, was accompanied by the loss of detection of GVA by PCR, thus providing further argument for the involment of GVA in the aetiology of KSG.
Relationships among Trialeurodes vaporariorum—Transmitted Yellowing Viruses from Europe and North America
Authors: Coffin R. S. , Coutts R. H. A. 
Published: May 2008

AbstractBeet pseudo‐yellows virus (BPYV), a possible closterovirus first identified in California, has long been thought to cause economically important whitefly‐transmitted diseases worldwide, although serological and molecular evidence for this is lacking. A yellowing virus prevalent in the UK in 1988, originally thought to be identical to BPYV, was shown by a specific reverse transcription polymerase chain reaction (RT‐PCR) test to differ from BPYV and from other whitefly‐transmitted yellowing viruses from France, The Netherlands, Spain and Turkey. Sequence analysis of a putative polymerase gene of the virus showed that it differed from known closterovirus genes, results suggesting that the virus may be an uncharacterized species. Following development of an RT‐PCR test diagnostic for currently prevalent whitefly‐transmitted yellowing viruses, a second virus was shown to be different from that found in 1988 but closely related to BPYV and the other yellowing viruses from Europe. This is the first direct evidence of a relationship between the latter and BPYV.
The Coffea arabica Fungal Pathosystem in New Caledonia: Interactions at Two Different Spatial Scales
Authors: Lamouroux N. , Pellegrin F. , Nandris D. , Kohler F. 
Published: May 2008

AbstractThe simultaneous analysis of epidemiological and environmental variables could contribute to the determination of the main factors which govern the epidemic dynamics of diseases (i.e. rust, anthracnose and Cercospora leaf spot) in Coffea arabica. With this in mind, the condition of previously marked leaves in 29 plots. which were grouped in 11 different sites in New Caledonia. were surveyed monthly. In the same period, the environmental characteristics of the plots (soil type, climate, etc.)were determined.Statistical analysis of these data revealed significant correlations between pathology and the environment. at the sites’ level (analysis of the mean site values) as well as at the plots' level (analysis of the deviations with the mean site value). The site effects predominated: at those sites in which rust was the major disease, leaf and branch mortality were more pronounced than at sites in which anthracnose or Cercospora leaf spot predominated. Rust was generally associated with soil pH values that were favourable for coffee tree development. with poor soil structure and with large temperature ranges. Within a site. plot exposure to sun and wind could enhance anthracnose and Cercospora leaf spot.Finally, in New Caledonia the three variables soil pH, soil structure and temperature range allow a simple and satisfactory estimation of the epidemiological risks in a given plot.
Rapid Tomato Seedling Assay for Virulent Isolates of Fusarium oxysporum F. sp. Radicis‐lycopersici (FORL), the Tomato Crown and Root Rot Pathogen
Authors: Madhosingh C. 
Published: May 2008

AbstractA rapid tomato seedling assay was developed for determining the relative wilt capacity of isolates of Fusarium oxysporum f. sp. radicis‐lyco‐persici (FORL), a virulent strain of the tomato pathogen. The procedures for the assay require that 5‐day‐old cv. Bonny Best tomato seedlings be dipped in 30‐day cell‐free concentrated culture filtrates of FORL isolates, which were grown in Czapek‐Dox medium with 2% Bacto‐casamino acids (CDA). The seedlings in the culture filtrates were then incubated at 30 C under artificial light (1200 ftcandles) at 28% relative humidity in a wind stream of 100–150 m min. The relative pathogenicity of the isolates was determined by inoculating the roots of 18‐day‐old seedlings with cultures of FORL isolates. The pattern of cell‐free filtrate wilt among the isolates was the same as that for the disease caused by cultures of the isolates. The seedlings treated with the filtrate from the most virulent isolate (Harrow HRS‐182) wilted in 20 min. The filtrates from less virulent isolates took progressively longer. up to 90 min. to cause comparable wilt. Isolate HRS‐082 was the first isolate also to induce disease in 10‐day‐old seedling assay. Both assays indicate three levels of wilt and disease capacities amongthe isolates examined. The utility of the assay in research and breeding for resistance is discussed.
Altered Expression of Erwinia amylovora HRP Genes in Tobacco Leaves Pretreated with Bacterial Protein‐Lipopolysaccharides
Authors: Minardi P. 
Published: May 2008

AbstractInfiltration of protein‐lipopolysaccharide complexes (pr LPS) (250 μg/ml) of Pseudomonas syringae pv. aptata into tobacco leaves protected against subsequent elicitation of the hypersensitive response (HR) by Erwinia amylovora. The effect of prLPS on the expression of E. amylovora hrp (hypersensitive response and pathogenicity) gencs was tested in protected tobacco leaves and in a defined medium in which hrp genes were highly expressed. Two,E. amylovora hrp loci transcriptionally fused with the Escherichia coliβ‐glucuronidase (Gus) coding sequence were used as chromosomal reporter genes. The prLPS treatment did not affect hrp gene expression of Hrp‐ mutants both in planta and in vitro, so the effect of prLPS treatment on hrp gene expression of two E. amylovora Hrp+ transformants was assayed during HR development in unprotected tissue and during the same time in prLPS protected tissue. A plasmid containing the same Gus fusions previously located in the chromosome was introduced into a wild‐type strain of E. amylovora. Gus activity was significantly lower in protected tissue. We suggest that HR inhibition by prLPS treatment requires the entire hrp gene cluster in order for the bacteria to send a signal to the plant. which, in turn, inhibits the expression of hrp genes.
Bipolaris multiformis (Jooste) Alcorn Pathogenic on Leaves of Cucumis sativus in Italy
Authors: Vannacci G. 
Published: May 2008

AbstractA destructive disease was observed in August 1981 in a field of Cucumis sativus cv. Radar. Sincc then sporadic spots on leaves of the same cultivar were recorded in 1985, 1988 and 1993. The causal agent was identified in Bipolaris multiformis (Jooste) Alcorn. The fungus produces frequently irregular (mostly Y‐shaped) conidia in culture but rarely on leaves. The pathogen germinates bipolarly in distilled water at 20–25°C (95 and 90% respectively), and on leaves it produces appressoria;, entry points are either stomata or the intact surface. Pathogenicity tests carried out on various cucurbitaceous plants showed symptom intensity decreasing with the following order: C. sativus cv. Radar and Eeballium elaterium > Brionia cretica subsp. dioica > Cueurbita pepo L. var. pommiformis and C. pepo var. patissonina f. radiata > C. moscata and Sechium edule. The other two tested cultivars of Cucumis sativus (Mezzolungo Marketer and Corto per sottaceti) and C. pepo cv. Verde scuro di Milano showed sterile, very small necrotic dot. Control plants, Citrullus lanatus cv. Sugar baby, Cucumbis melo and Lagenaria siceraria showed no symptoms.
Characterization and Cytopathology of Hibiscus Latent Ringspot Virus Isolated from Kenaf (Hibiscus cannabinus L.) in Italy
Authors: Rubies‐Autonell C. , Turina M. 
Published: May 2008

AbstractHibiscus latent ringspot virus (HLRV) was isolated from kenaf plants (Hibiscus cannabinus L.) in Italy. and identified as III. RV by its host range, purification, electron microscopy and serology. Ultrastructural studies showed that infected plants contained membranous cytoplasmic inclusion bodies. characteristic of nepoviruses, and sometimes also crystalline aggregates.
Effect of Temperature and Air Humidity on Multiplication of Xanthomonas campestris pv. undulosa and Symptom Expression in Susceptible and Field‐Tolerant Wheat Genotypes
Authors: Duveiller E. , Maraite H. 
Published: May 2008

AbstractMultiplication of Xanthomonas campestris pv. undulosa in the leaf tissues of susceptible and field‐tolerant wheat genotypes was determined at the secdling stage, under different incubation conditions of temperature and air humidity. Dry air conditions did not hamper the multiplication of the population trend. Symptoms were not observed at 15°C. The occurrence of lesions coincided with populations of baeteria that had reached an estimated threshold of 108 colony forming units/leaf. Differences in populations between genotypes Alondra and Pavon were only noticeable at 25°C and dry air conditions, without correlation to differences in symptom expression. Considering these two genotypes, resistance to bacterial leaf streak did not seem to operate at the seedling stage when plants were inoeulated by infiltration. In both genotypes, lesions did not extend significantly. An aetive mechanism stopping bacterial growth which is apparently temperature‐dependent or a saturation of the, target sites was possibly involved, as shown in the different experiments by the fit‐curves calculated for Alondra and Pavon. This study provided information on the role of climatic factors in relation to epidemics. Temperature appeared to have a major effect on the disease and results confirmed that the risk of bacterial leaf streak prevails in warmer non‐traditional wheat growing areas. Several types of resistance are likely to exist in the X. e. pv. undulosa/wheat system.
Spontaneous Genetic Variation for Leaf Rust Reaction in Sinvalocho MA Wheat
Authors: Sacco F. , Favret E. A. , Suarez E. Y. , Solari R. M. , Saione H. A. 
Published: May 2008

AbstractSpontaneous off‐type plants for leaf rust reaction to Argentine races 66 and 77 of Puccinia recondita tritici were found at rates of 3.4 per 1000 and 0.44 per 1000, respectively, in the progeny of self‐pollinated (bagged) spikes of Sinvalocho, MA wheat. Leaf rust reaction changes were associated to aneuploidy in most cases. The variation to race 66 was associated to monosomy of chromosome 6B or probably deletions on chromosome arm 6BL. Some off‐type plants however showed, in subsequent generations. changes for reaction to race 77 or simultaneous changes to races 66 and 77 as well as changes in leucine aminopeptidase isozyme expression, which cannot be explained on grounds of allelic dosage. The origin of these genetic and chromosomal changesis not clear in some cases, however, a common origin could be suggested by the presence of transposonlike elements.
A Method for the Quantitative Assessment of Wound‐induced Chitinase Activity in Potato Tubers
Authors: Appel M. , De Ries G. F. W. , Hofmeyr J.‐H. S. , Bellstedt D. U. 
Published: May 2008

AbstractA method for the quantitative assessment of chitinase activity was developed. Dilution series of crude potato tuber chitinase extracts were assayed with a colorimetric microtitre plate assay. using CM‐chitin‐RBV as enzyme substrate. Linearity between absorbance values mea‐sured (540 nm) and enzyme concentration was found to be limited to the low concentration range. where depletion of the substrate was no longer limiting. As as absorbance of 0.1 always fell within the concentration range for which absorbance‐concentration linearity was valid. one unit of enzyme activity was defined as the amount of enzyme needed to yield and A of 0.1. A more reliable method for the assessment of chitinase activity was established by basing the difinition of enzyme, activity on a concentration rather than on as absorbance value. as was done previously. Using this method, differences in the rate of chitinase induction upon wounding were demonstrated for six commercial potato cultivars.
Oxidative Protective Mechanisms and Resistance to the Dicarboximide Fungicide, Iprodione, in Alternaria alternata
Authors: Steel C. C. , Nair N. G. 
Published: May 2008

AbstractThe free radical scavengers α‐tocopherol and butylated hydroxytoluene, but not ascorbate, diminished the growth‐inhibiting effects of the dicarboximide fungicide, iprodione in Alternaria alternata. Growth of A. alternata in the presence of iprodione increased the activities of superoxide dismutase and glutathione reductase while catalase was unaffected. Four iprodione sensitive and four iprodione resistant isolates of A. alternata were compared for activity of free radical enzymes. The isolates of A. alternata resistant to iprodione had more catalase activity than those which were sensitive, but did not differ in superoxide dismutase of glutathione reductase, activities. 3‐Amino‐1.24.‐triazole, a specific inhibitor of catalas, reduced the ability of DAR 69775, a dicarboximide resistant isolate of A. alternata. to grow in the presence of iprodione. In A. alternata dicarboximide resistance appeats to be at least partially mediated by enhanced activitiesof, catalase.
Characteristics of Serially Produced Zoospore Suspensions of Polymyxa betae for Transmission of Beet Necrotic Yellow Vein Virus
Authors: Dirven J. A. A. M. , Peters D. 
Published: May 2008

AbstractZoospore suspensions of Polymyxa betae were analysed for their potential as inocula to infect sugar beet plants with beet necrotic yellow vein furovirus. The infectivity could be maintained when zoospore suspensions were serially transferred. When zoospore‐producing seedlings were individually transferred some of these seedlings lost their infectivity after several passages. Infectivity was first detected in suspensions within I day after inoculation of the plant by zoospores. The suspensions remained infectious for at least 10 h after removal of the plants producing viruliferous zoospores. Both the number of test plants infected and the concentration of virus that developed were greater at 25 C than at 20 C.
Susceptibility of Barley Cultivars and Lines to Fusarium Infection and Mycotoxin Accumulation in Kernels
Authors: Perkowski J. , Kiecana I. , Chelkowski J. 
Published: May 2008

AbstractHeads of 12 barley genotypes (8 cultivars and 4 lines) were inoculated with conidial suspension of the following single isolates: F. culmorum no. 3, F. graminearum no. 122 and F. sporotrichioides no. ATCC 62 360. The number of kernels per head. 1000 Kernel weight and yield have been calculated for each genotype. Seed samples collected at harvest were analysed for each genotype. Seed samples collected at harvest were analysed for several trichothecene mycotoxins and zearalenone.The mycotoxin concentrations (mg/kg) in barley kernels inoculated with F. graminearum were as follows. deoxynivalenol (DON) 0.1 to 5.4 (av. 2.3). 3‐acetyldeoxy‐nivalenol (3‐AcDON) 0.0–0.2 (av. 0.1), 15‐acetyldeoxynivalenol (15‐AcDON) 0.0–0.7 (av.0.2), nivalenol (NIV) 0.0–0.8 (av. 0.3). zearalenone (ZEA) 0.0–0.1 (av. 0.0); F. culmorum: DON 0.6 to 12.0 (av. 5.3), 3‐AcDON 0.1 to 1.0 (av. 0.6). 15‐AcDON nd. NIV 0.1–0.7 (av. 0.3). ZEA 0.1–0.5 (av. 0.2). F. sporotrichioides T‐2 toxin 2.4–13.9 (av. 6.0), HT‐2‐toxin 0.1–0.8 (av.0.3) and neosolaniol 0.2–1.5 (av.0.7).
Different Assessment Techniques of Leaf Blotch (Rhynchosporium secalis (Oud.) J. Davis) in Winter Barley after Artificial Inoculation
Authors: Foroughi‐Wehr B. , Lind V. , Zöchner S. , Rabenstein F. 
Published: May 2008

AbstractSeven winter barley cultivars expressing different field resistance against leaf blotch (Rhynchosporium secalis) and 60 doubled haploid (DH) lines descending from and F1 hybrid resistant x susceptible were used to develop a test for the quantitative determination of disease severity. Differences in the level of resistance could be measured very precisely after artificial infection of seedlings at the 4‐leaf‐stage and subseqent incubation at 7 C. The protein of six isolates was usedf, or antiserum production which was subsequently supplied for serological testing (Enzyme‐Linked‐Immunosorbent‐Assay) of infected leaves. The results of visible scoring of the seedlings was significantly correlated with measuring with the ELISA reader. The, results of the seedling test also corresponded to field scores after natural infection.
Effects of Induced Resistance on Disease Severity/Yield Relations in Mildewed Barley
Authors: Kehlenbeck H. , Schönbeck F. 
Published: May 2008

AbstractField experiments showed that the treatment of winter barley with microbial metabolites produced by a Bacillus subtilis strain led to increased yields in spite of a remaining mildew infection. Disease severity/yield relations obtained on a single tiller basis for either mildew infection at EC 75 or area under disease progress curve (AUDPC) were negatively correlated for untreated plants (R2= 89%, 94%) while this relation did not exist for inducer‐treated ones (R2= 10%, 13%). Despite an increasing infection density. yields of main tillers of inducertreated plants were not decreased. On the other hand area under green leaf area curve (AUGLAC) showed a higher correlation with grain yield (R2= 89%) of inducer‐treated plants. Possible explanations for the mitigated damaging effect of powdery mildew were expected in carbohydrate metabolism. especially carbohydrate formation and translocation. Assimilation rates of flag leaves of inducer‐treated barley with similar infection densities to those of untreated plants were increased over a prolonged period and even exceeded those of non infected ones. In inducer‐treated plants the export of 14CO2 from flag leaves into ears remained unimpaired by mildew infection and the allocation of assimilates to grains was highest at late stages of grain filling. Obviously plants were stimulated by inducer treatments to compensate for the damaging effect of powdery mildew and to tolerate mildew infection without yield loss.
Chrysanthemum Stem Necrosis Caused by a Possible Novel Tospovirus
Authors: Duarte L. M. L. , Rivas E. B. , Alexandre M. A. V. , De ÁVila A. C. , Nagata T. , Chagas C. M. 
Published: May 2008

AbstractNecrotic lesions surrounded by yellow areas on leaves followed by stem necrosis were observed on chrysanthemum plants cultivated in Atibaia, Sào Paulo State, Brazil. The host range, in vitro properties and particle morphology of the causal virus were typical of a Tospovirus. Serological studies demonstrated that the virus differed from tomato spotted wilt. tomato chlorotic spot, groundnut ringspot and inpatiens necrotic spot Tospoviruses. The virus isolate is thus possibly a representativeof a new serogroup of a new virus.
Use of Cross‐Reactive Antibodies to Detect Members of the Potyviridae
Authors: Richter J. , Rabenstein F. , Proll E. , Vetten H. J. 
Published: May 2008

AbstractIn attempts to use cross‐reacting antibodies for the broad‐spectrum detection of potyviruses two broad‐spectrum immunoreagents, the monoclonal antibody P‐3‐3H8 and antiserum Tu MV‐314 raised against an isolate of peanut stripe virus and turnip mosaic virus, respectively, were examined for their ability to detect members of the Potyviridae in a simple indirect plate‐trapped antigen (PTA) ELISA. Both immuno‐reagents reacted strongly not only with isolate of 50 different virus species of the genus Potyvirus but also with several isolates of ryegrass mosaic virus, the type member of the genus Rymovirus A few members of the genus Potyvirus as well as agropyton mosaic and hordeum mosaic viruses, two other species of the genus, Rymovirus did not react with P‐3‐3H8 but only with TuMV‐314 which showed the highest degree of cross‐reactivity. In no case were positive reactions obtained with members of the genera Bymovirus and Ipomovirus. These two immunoreagents which appear to be directed to conserved epitopes gave good results when they were employed for detecting potyviruses in field samples from ornamental (Liliales) and leguminous plants. The potential and limitations of cross‐reactive antibodies for the routine detection of potyviruses are discussed.
VerticilliumWilt of Pepper (Capsicum annuum) in Morocco
Authors: Douira A. , Ben Kirane R. , Ouazzani Touhami A. , Okeke B. , Elhaloui N. E. 
Published: May 2008

AbstractPepper crops in Morocco formerly thought to be free from attack byVerticilliumwere found to be susceptible to this pathogen.Verticilliumwilt of pepper was observed in plots where the crop was cultivated in rotation with tomatoes. Strains ofVerticilliumisolated from pepper possessed different morphological and pathogenic characteristics.
Fusarium moniliforme Sheldon — Pathogenicity to Wheat Seedlings and Ability to Produce Fumonisins
Authors: Chelkowski J. , Visconti A. , Dokko B. , Wiśniewska H. 
Published: May 2008

AbstractAll 17 examined Polish isolates of Fusarium moniliforme Sheldon [syn. F. verticillioides (Sacc.) Nirenberg], originating from wheat, maize and barley kernels, exhibited pathogenicity to wheat seedlings of the cultivar ‘Almari’ (5 isolates‐very strong, 3 strong, 3 medium, 5 weak and only one very weak). The same isolates were able to produce the mycotoxins fumonisins on rice under laboratory conditions. Fumonisin B1 (FB1) was detected in concentrations ranging from 1.3 to 2240mg/kg and fumonisin B2(FB2) from 0.7 to 600 mg/kg. The yield of the fumonisins produced in vitro was not related to the pathogenicity of individual isolates.