bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of Populations of Softrot Bacteria on Witloof Chicory Leaves during Root Production in the Field
Authors: Schober B. M. , Zadoks J. C. 
Published: May 2008

AbstractDuring a 4.‐year field experiment at ihe Experimental Slatton for Arable Farming in Lelystad, the Netherlands, witloof chicory plants, grown for root production, were surveyed for Ihe presence of epiphylic or saprophytic populations of the softrot bacteria (Enriniu carotovora and Pseudomonus marginalia) on their leaves. Isolates of pectolytic bacteria collected frotn the leaves were identified and the influence of environmental variables was assessed testing the hypothesis of an increase of the number of isolates on plants in the field. A significant linear correlation (R‐ = 0,47, n= 20, P = 0.002) was found for the regression of the number of pectolytic isolates on titne (tnonth) and temperature (monthly average). The average monthly growth rate of the softrot bacteria was significantly greater than zero during the field seasoti, indicating an increase of the populations of softrot bacteria. The ratio between the number of Envinia and Pseudomonus isolates changed during the growing season from a predominance of pseudomonads frorn May until July to ati equal ratio from Atigust until harvest. The number of isolates of Erwinia carotovora was negatively correlated with total global radiation. The increase in the number of Ecc later in the growing season was attributed to protection from high radiation levels and adverse temperatures in the tmicroclimate under the canopy.
Bark Canker of Persian Walnut (Juglans regia) Trees Incited by Erwinia nigrifluens in Italy
Authors: Morone C. , Janse J. D. , Scortichini M. 
Published: May 2008

AbstractIn autumn 1996, adult Persian walnut (Juglans regia L.) trees cultivated in Piedmont (north‐west of Italy) showed irregularly shaped cankers along the bark. When the phelloderm was removed, extensive necrosis of the tissues below was observed. A watery, dark‐coloured exudale was also frequently observed. Symptoms were present on approximately 10% of 600 trees. Biochemical, nutritional and pathogenicity tests as well as fatty acids analysis of the isolates and type‐strain, indicated that Erwinia nigrifluens was the causal agent of the disease. This is the first report of this pathogen in Italy.
Persistence of the European Stone Fruit Yellows Phytoplasma in Aerial Parts of Prunus Taxa During the Dormant Season
Authors: Seemüller E. , Stolz H. , Kison H. 
Published: May 2008

AbstractFluorescence microscopy and PCR as well as graft transmission experiments were employed to examine the persistence of the European stone fruit phytoplasma in the stem of various Prunus taxa during the dormant season. Both approaches revealed that the phytoplasma pathogen persists in the aerial parts of the trees in all stone fruit taxa examined.
Phylogenetic Inference Based on Information Theory‐Based PCR Amplification
Authors: Tooley P. W. , Salvo J. J. , Schneider T. D. , Rogan P. K. 
Published: May 2008

AbstractAs a method for the determination of the taxonomic affinities of plant pathogens and other organisms, a set of ‘universal’ polymerase chain reaction (PCR) primers which amplify a taxonomically diverse sequence domain of 28S ribosomal DNA (rDNA) were designed. The PCR primers chosen by information‐theory analysis generated PCR products using DNA templates from a wide diversity of organisms. Sequences of PCR products were then obtained which allowed phylogenetic dendrograms to be constructed. Based on the above analysis, the Oomycete pathogen Phytophthora infestans clustered with the protist Prorocentrum micans rather than with representatives of the true fungi, consistent with its designation as a ‘pseudofungus’, Magnaporthe grisea. another important plant pathogen, clustered with the true fungi as expected. The approach described can be used with other plant pathogens to clarify phytogeny of new or ambiguously designated species.
Occurrence of Soil Suppressiveness toFusariumWilt Disease of Broad Bean in Ismailia Governorate
Authors: Wahid O. A. Abdul , Ibrahim M. E. , Omar M. A. 
Published: May 2008

AbstractFusarium oxysporumwilt of broad beati was studied in nonsuppressive and suppressive soil. One hundred and fifty soil samples were collected from 10 cultivated and reclaimed fields. The disease response of the 10 fields showed great variation. Percentages of diseased plants ranged from 19 to 85%. Soil samples collected from field Fm2 (soil No. 6, suppressive) showed the lowest percentage of diseased plant (19%), while all other soils showed not less than 40% of diseased plants. When the 10 field soil samples were inoculated withF. oxysporumthey exhibited a high receptivity value (over 50% diseased plants) while Fm2 soil showed almost the least value (less than 10% diseased plants). The fungal flora of the soil samples was studied where 64 spp. belonging to 37 genera were recovered. While the lowest number was recorded in soil Pk1 (soil No. 2, nonsuppressive) the highest total and species counts was found in Fm2 soil. Chemical analysis revealed that chloride and calcium ions were higher in Fm2 soil. The number of chloride ions was higher than calcium ions in all samples. Sugar cane bagasse, an organic supplement, and autoclaving enhanced the wilt disease development and retarded the suppressiveness of Fm2 soil.
Application of In Vitro Therapy for Ilarvirus Elimination in Three Prunus Species
Authors: GELLA R. , ERREA P. 
Published: May 2008

AbstractApricot (Prunus armeniaca) shoot cultures infected with apple chlorotic leaf spot virus (ACLSV). peach (Prunus persica) shoot cultures infected with Prunus necrotic ring‐spot virus (PNRSV) and ACLSV and sour cherry (Prunus avium) shoot cultures infected with prune dwarf virus (PDV) and ACLSV. were selected to evaluate the response of in vitro grown shoots to thermotherapy and to eliminate the viruses from the plant. A constant temperature regime was selected for the heat treatment (37° C). The period of heat treatment applied to each cultivar and species was variable, between 15 and 36 days, and the range of success in the elimination of virus had percentages between 37 and 100% of virus‐free plants for PNRSV. 60 to 100% for ACLSV and 85 to 100% for PDV. The combination of the therapy and tissue culture techniques has been shown to be a simple and efficient method to eliminate these viruses in Prunus sp. despite variability observed among species in shoot survival and elimination of the viruses. The advantage of this method in comparison with other methods used in virus elimination in fruit species is discussed.
Spatial and Temporal Variation of Genetic Marker Patterns in Setosphaeria turcica Populations from Kenya
Authors: Borchardt D. S. , Welz H. G. , Geiger H. H. 
Published: May 2008

Abstract Setosphaeria turcica is an important fungal pathogen of maize in the humid mid‐altitude and highland environments of East Africa, causing northern corn leaf blight. To conduct a population genetic analysis, a total of 172 S. turcica isolates from four locations in western (Kakamega, Kitale) and central (Embu, Kikuyu) Kenya, collected in 1994 and 1995, were examined with 43 random amplified polymorphic DNA (RAPD) markers. Mating types were also determined. Of the total genetic variation, the greatest portion (70%) was attributed to differences between haplotypes in local populations. Only 26% of the variation was due to differences between regions and 4% to locations within regions. Populations from the two regions clearly differed in their haplotype similarities and had different levels of gene and genotypic diversity. Isolation by distance and divergent selection are likely to be major causes of the differentiation between western and central Kenya. Migration between the two regions was weak. Within regions, population samples from different locations were very similar indicating intense migration. Samples collected early and late in the vegetation period or in consecutive years always showed the same population structure, i.e. little fluctuation occurred during the season. Clones were shown to be conserved over long distances and over years despite sexual recombination and an extremely high genotypic diversity.
Diversity of Plasmids of Agrobacterium tumefaciens Isolated from Fruit Trees in Poland
Authors: Pulawska J. , Malinowski T. , Sobiczewski P. 
Published: May 2008

AbstractPlasmid DNA was isolated from 11 strains of Agro‐bacterium tumefaciens originated from 6 fruit tree species of various locations in Poland. One to four plasmids were consistently isolated from all studied strains. Plasmid sizes varied from about 27 to about 315 kbp. Some of the strains possessed similar plasmid profiles. The lack of any clear relationship between plasmid profiles of strains and their virulence, sensitivity to agrocin 84, biovar and origin was observed.
Comparison of Pea Enation Mosaic Virus (PEMV) Isolates: Sequence of Coat Protein and Aphid Transmission Protein Genes of a European Isolate
Authors: Salgueiro S. , Hull R. 
Published: May 2008

AbstractPea enation mosaic virus (PEMV) is a bipartite virus, transmitted mechanically and by aphids in the circulative manner. Virus capsid proteins, coded by RNA‐1 are involved in aphid transmissibility. Using an antiserum against a European (UK) aphid‐transmissible isolate, the capsid proteins of six PEMV isolates, each aphid‐transmissible or non‐transmissible, were compared using Western blots. All isolates have a major coat protein of approximately 22 kDa, but also additional proteins. RNA‐1 complementary DNAs corresponding to ORFs 4 and 5 of isolate SP were cloned and sequenced. This had 95% homology at the nucleotide level and a 96% homology at the amino acid level with the sequence of a North American isolate. Most amino acid differences were in the region corresponding to ORF 5, some of which could result in potential changes in the conformation of the protein. This is the first report on the sequence of an European PEMV isolate and the first direct comparison of viral capsid complexity in different PEMV isolates.
Specific Detection of Xanthomonas axonopodis pv. manihotis with a DNA Hybridization Probe
Authors: Verdier V. , Mosquera G. 
Published: May 2008

AbstractA dot‐blot assay was developed for the detection of Xanthomonas axonopodis pv. manihotis (Xam), the causal agent of cassava bacterial blight. A 898 bp DNA fragment unique to Xam strains was cloned and evaluated as a diagnostic DNA probe. The DNA probe (p898) hybridized with the total DNA of 362 Xam strains tested but not with any of the 40 other Xanthomonas strains tested or with saprophytes associated with the cassava plant. A quick colony hybridization procedure was developed to identify Xam strains. The probe also detected Xam strains in crude extracts of leaf and stem lesions, and in cassava fruits and sexual seeds that were naturally infected. The overall sensitivity of the dot blot method for detecting Xam in stem and leaf samples was about 103 colony‐forming units per reaction. Because the dot‐blot hybridization technique is sensitive and rapid, it can be easily used for culture indexing.
Erwinia and Pseudomonas Bacteria can be Reliably Screened by an Improved Serological Agglutination Test
Authors: Mráz I. , Pánková I. , Petrzik K. , Šíp M. 
Published: May 2008

AbstractThe sensitivity of a modified agglutination test for the detection of Erwinia amylovora and Pseudomonas syringae pv. pisi antisera was examined. The bacterial polyclonal antisera were sensitized by Staphylococcus aureus bacteria. These antisera enhanced the sensitivity of the agglutination test by two or three times. The modification of the agglutination test described is recommended for the detection of E. amylovora in plant sap and in bacterial slime of hawthorns (Crataegus sp.) attacked by E. amylovora.
Sunflower Coumarin Phytoalexins Inhibit the Growth of the Virulent Pathogen Sclerotinia sclerotiorum
Authors: Urdangarín C. , Regente M. C. , Jorrín J. , de la Canal L. 
Published: May 2008

AbstractThe fungus Sclerotinia sclerotiorum causes serious damage to sunflower crops. The effect of two major sunflower phytoalexins, ayapin and scopoletin, on the growth of S. sclerotiorum has been examined; both inhibited mycelial growth in vitro, but at different rates. The concentration necessary to obtain 50% inhibition of fungal growth (IC50 values) determined for ayapin and scopoletin were 0.16 mm and 1.5 mm, respectively. Other sunflower phenolic metabolites such as caffeic acid, chlorogenic acid, and isoliquiritigenin had no inhibitory effect on S. sclerotiorum growth at concentrations as high as 2 mm. These results, together with previously reported data, suggest that coumarin biosynthesis‐accumulation in sunflower may be another target for plant breeding and genetic engineering strategies aimed at obtaining sunflower varieties with enhanced resistance to Sclerotinia rot.
Leaf Hairs as a Basic Protective Barrier against Downy Mildew of Grape
Authors: Kortekamp A. , Zyprian E. 
Published: May 2008

AbstractThe influence of hairs during the interaction of Plasmopara viticola with leaves of four Vitis species was studied both under natural conditions and upon treatment with the detergent Tween 20. The hydrophobic felt consisting of hairs on the adaxial leaf sides repels water from the leaf surface preventing a successful penetration of the host via fungal germ tubes. Treatment with a detergent solution led to an enhanced attachment of water droplets. As a consequence of the detergent treatment, infection structures of P. viticola were formed on the field‐resistant hosts Vitis doaniana and Vitis davidii as in the susceptible Vitis vinifera hosts. It can be concluded that covering the leaf surface with hydrophobic hairs represents a major defence strategy and that the infection process is dependent on wetness. Although in Vitis cinerea and Vitis labrusca primary infection structures can be monitored after detergent treatment, the growth of the fungus was found to be restricted in these species indicating the action of additional or different defence strategies.
Survival of Softrot Bacteria during the Storage of Witloof Chicory Roots
Authors: Schober B. M. , Zadoks J. C. 
Published: May 2008

AbstractDuring the cold storage of witloof chicory roots, changes in the populations of the softrot bacteria Erwinia carotovora ssp. carotovora (Ecc), Erwinia carotovora ssp. atroseptica (Eca) and Pseudomonas marginalis (Pm) were investigated from October (directly after harvest) until March of the next year. Colonization incidence of Ecc and Pm changed during the early weeks of storage in each of the 3 years of the experiment and increased significantly after December, approximately 6 to 8 weeks after the roots had been placed in storage. After inoculation, during storage in 1996, populations of Eca decreased continuously from 5.8 × 105 CFU/ml to 103 CFU/ml 4 weeks later in mid‐November without any further statistically significant increase during the rest of the storage period. Timecourse analysis of the monthly colonization incidence of Ecc and Pm over the 3 years revealed that the incidence was significantly dependent on the incidence 2 weeks earlier. Also, high colonization incidences during storage coincided with high disease incidence during the following forcing period of the roots. Therefore, a forecast of disease incidence during forcing of the witloof chicory heads may be envisaged.
Ralstonia (Pseudomonas) solanacearum race 3, biovar 2, Detected in Surface (irrigation) Water in Egypt
Authors: Farag N. , Stead D. E. , Janse J. D. 
Published: May 2008

AbstractThe causal agent of potato brown rot, Ralstonia (Pseudomonas) solanacearum was demonstrated for the first time to be present in surface (irrigation) water in Egypt. The bacterium was identified in both irrigation and drainage canals near to infected fields within three potato‐growing areas in the delta that were already known to be infected. The bacterium was found in populations of up to 106 colony‐forming units per litre. No weed hosts such as Solanum dulcamara were found along the canals. The bacterium was not detected anywhere in the desert area. These findings show that irrigation water can play a role in the epidemiology of the brown rot disease in Egypt and further studies are necessary to determine its exact role. The use of artesian water in the desert area and avoidance of re‐use of irrigation water could be important factors in the avoidance of brown rot problems.
A Carrot Proliferation Disease Associated with Rickettsia‐like Organisms in the Czech Republic
Authors: Fránová J. , KAREŠOVÁ R. , Navrátil M. , šimková M. , Válová P. , Nebesáŕová J. 
Published: May 2008

AbstractCarrot plants showing severe proliferation symptoms were observed in East Bohemia in 1996. Blue‐while fluorescent areas were observed under fluorescence microscope in sieve tube cells of symptomatic plants, but not in healthy ones. Scanning electron microscopy revealed the presence of elongated structures in the phloem sieve elements of diseased carrots. Transmission electron microscopy revealed rickettsia‐like organisms present in sieve tube elements of symptomatic plants. The diameter of the bodies ranged from about 0.2‐0.3μm. and the length of the elongated forms reached 2.2 μm. No other organisms were detected. This is the first report of infection by single rickettsia‐like organisms on carrot plants.
Expression of clusterin in normal and preeclamptic placentas
Authors: Shin Jeong‐Kyu , Han Kyung‐An , Kang Min‐Young , Kim Yoon‐Sook , Park Ji‐Kwon , Choi Won‐Jun , Lee Soon‐Ae , Lee Jong‐Hak , Choi Wan‐Sung , Paik Won‐Young 
Published: May 2008

AbstractAim:  Clusterin is a multifunctional protein that is up‐regulated during many different pathophysiological states. Clusterin may be related to a compensation mechanism involving aggregation of soluble proteins, inhibition of complement‐mediated cell damage, adaptive regeneration or apoptosis. Clusterin may increase in response to cell damage that results from hypoxic stress in the preeclamptic placenta. The goal of this study was to measure clusterin expression and localization in normal and preeclamptic placental tissues.Methods:  Immnunohistochemical and double immunofluorescent staining for clusterin was performed on eight normal and eight preeclamptic placental tissues, and clusterin expression was quantified by Western blotting.Results:  Immunohistochemical analysis of clusterin in placental tissues obtained from normal pregnancies and those with preeclampsia showed localization of clusterin mainly in the syncytiotrophoblasts and villous endothelial cells. In the double immunofluorescent staining, clusterin was detected in the cytoplasm. The Western blot analysis showed that clusterin expression in the placental tissues of the preeclampsia group was significantly higher than in the normal pregnancy group.Conclusions:  Increased expression of clusterin in placental tissues might play an important role in the pathogenesis of preeclampsia.
Slow programmable and ultra‐rapid freezing of human embryos
Authors: Vutyavanich Teraporn , Sreshthaputra Opas , Mongkolchaipak Suchada , Wongtra‐ngan Supreeya , Piromlertamorn Waraporn 
Published: May 2008

AbstractAim:  To compare the outcomes of slow freezing with ultra‐rapid freezing (URF) of cleavage‐stage human embryos on aluminum foil.Methods:  Two‐cell mouse embryos were used to test our method of ultra‐rapid freezing. The embryos were randomly allocated to a non‐frozen control (208 embryos), and slow (204 embryos) or ultra‐rapid freezing groups (204 embryos). Immediate survival rate, further cleavage and blastocyst formation were compared. After validating our ultra‐rapid freezing method on mouse embryos, we applied a similar ultra‐rapid freezing protocol to human embryos. Consecutive human frozen/thawed embryo transfer (FET) cycles from October 1998 to June 2005 were reviewed. The survival rate, further cleavage rate and the pregnancy outcomes were compared between the URF and slow programmable freezing.Results:  Mouse embryos in the URF group survived the freezing/thawing process better than those in the slow freezing group (93.1% vs 82.8%, P = 0.001). Blastocyst and hatching blastocyst formation of the surviving embryos were comparable in the URF and slow freezing group (59% vs 58.6%, P = 0.944 and 32.6% vs 42%, P = 0.066, respectively). There were 146 human FET cycles in the URF group and 28 cycles in the slow freezing group. The immediate survival of embryos was higher in the URF group than in the slow freezing group (87.9% and 64.3%, P < 0.001). There was no significant difference in the mean number of embryos per transfer (3.7 ± 1.3 and 3.3 ± 1.2, P = 0.178), clinical pregnancy rate per transfer (28.5% and 21.4%, P = 0.444) and implantation rate per embryo (10.98% and 10.9%, P = 0.974) in the URF or slow freezing groups.Conclusion:  Our in‐house URF method gave comparable results to slow programmable freezing. Although the risk of potential contamination is a major drawback of the present ultra‐rapid freezing technique, future refinement will minimize or entirely eliminate this concern.
Fetal nasal bone length and Down syndrome during the second trimester in a Chinese population
Authors: Hung Jeng‐Hsiu , Fu Chong Yau , Chen Chih‐Yao , Chao Kuan‐Chong , Hung Jamie 
Published: May 2008

AbstractObjective:  The purpose of the present study was to build a database of reference ranges of fetal nasal bone length (NBL) in a Chinese population. The accuracy rate of detecting Down syndrome was also analyzed using fetal NBL as a marker.Methods:  The control group of fetuses included 342 normal singleton pregnancies with no chromosomal or congenital anomalies. The present study was a cross‐section study and the control group was used to construct percentile values of NBL from 13 to 29 gestational weeks of age. Two‐dimensional ultrasonography was used for the nasal bone studies. Measurements of NBL were collected and each fetus contributed a single value to the reference sample. During the study period, 14 fetuses with Down syndrome were examined. Measurement of fetal NBL was made during amniocentesis, with gestational age ranging from 13 to 19 weeks.Results:  From 342 normal fetuses with gestational age ranging from 13 to 29 weeks, reference ranges of NBL were constructed. The reference ranges were constructed from the 100(1 − p)% reference range: , where Ŷ = 25 − exp(3.58 − 0.044 × t + 0.0006 × t2), with Ŷ being the fitted mean of regression model and t being gestational age (weeks). Using fetal NBL, the regression model was Pr(Down syndrome) = exp(W)/[1 + exp(W)], where W = 0.62–4.80 × NBL (multiples of the median) in predicting Down syndrome. Fetal NBL was found to have a sensitivity and specificity of 0.78 and 0.78, respectively, in predicting Down syndrome in the second trimester of pregnancy.Conclusions:  Fetal NBL measurement can provide a simple and useful algorithm to predict Down syndrome during the second trimester of pregnancy.