bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction studies on number of teratocytes and eggs of Microplitis rufiventris Kok. (Hym., Braconidae) parasitoid in superparasitized host larvae
Authors: Khafagi W. E. , Hegazi E. M. , Showail S. 
Published: March 2003

1 Introduction Microplitis rufiventris Kok. (Hym., Braconidae) is an internal solitary parasitoid of many noctuid caterpillars including the cotton leafworm Spodoptera littoralis (Boisd.) (
Kokujev 1914;
Hammad et al. 1965
;
Gerling 1969), the lesser cotton worm S. exigua Hbn. (
Meier 1929;
Thompson 1946;
El‐Minshawy 1963); S. latebrosa Lederer (
Hammad et al. 1965
) and American bollworm Heliothis armigera Hbn. (
Meier 1929;
Ibrahim & Tawfik 1975). When the egg of M. rufiventris hatches in its host, S. littoralis, spherical cells from the serosa that envelope the parasitoid embryo are released into the host’s haemolymph. Approximately 400 cells are liberated from an egg of the parasitoid. These cells increase in size, reaching a maximum average diameter of 137 μm at the completion of parasitoid development (
Khafagi 1997). These cells are most frequently called ‘teratocytes’ (
— 1968
, 1971;
Vinson 1970). It is reported that the presence of large numbers of the teratocytes is indicative of superparasitism but their number does not give an indication to the exact number of parasitoid eggs from which the cells have been derived (
—, — Khafagi et al. 1998
) . Therefore, it was of interest to initiate prediction studies on egg and teratocyte numbers in superparasitized host larvae.
Interference of Copper Sulphate in Growth of Erwinia amylovora
Authors: Geider K. 
Published: March 2003

AbstractTo understand the toxicity of copper salts on Erwinia amylovora, which are used in the control of fire blight, bacterial growth and cell metabolism was assayed with copper sulphate in the presence or absence of complex‐forming compounds such as various amino acids or citrate. In minimal medium without amino acids copper sulphate strongly interfered with the growth of E. amylovora. A concentration of 15 μm CuSO4 resulted in about 50% growth inhibition. In contrast to a strong effect of streptomycin, copper ions barely killed the cells when incubated in minimal medium for 1 h. The addition of 4 g asparagine per litre relieved a‘bacteriostatic’effect of copper ions and allowed growth of the bacteria at 2 mm CuSO4. Other amino acids had a similar effect in the protection of E. amylovora against copper ions. This was in contrast to glycine betain, which was unable to suppress growth inhibition by CuSO4. Presumably, the free ammonium groups of amino acids participated in the protective effect. The addition of citrate, exceeding the amount of copper‐ions, was also protective. Bioluminescence of E. amylovora cells was expressed via a constitutive promoter from the lux‐operon of Vibrio fischeri. The light emission is dependent on active cell metabolism. In a novel approach to determine the immediate response of E. amylovora after the addition of copper sulphate, the change of bioluminescence was determined. Addition of copper ions to MM3 medium strongly affected the bioluminescence, but no change in light production was noticed, when citrate or asparagine were present in addition to copper sulphate. A decrease of bioluminescence to 50% was observed for 50 μm CuSO4 in the absence of amino acids.
Bacterial Canker of Peach: Effect of Tree Winter Water Content on the Spread of Infection Through Frost‐related Water Soaking in Stems
Authors: Vigouroux A. 
Published: March 2003

AbstractSeveral experiments were conducted to study the influence of water content in trees on dye diffusion or controlled Pseudomonas syringae pv. persicae infection spread induced in winter by water soaking after freezing and thawing. These were carried out in a cold cabinet in excised dormant hardy 1‐year‐old slightly dehydrated or rehydrated peach shoots, and in whole variably hydrated peach trees cultivated outdoors in 3001 containers. In shoots, dye diffusion was more substantial and infection more widespread when water content was higher. In potted peach trees, the spread of individual bacterial cankers which was induced by inoculating different shoots over two successive winters, was more restricted when tree water content was lower. In both years, a high positive correlation coefficient was observed between individual tree water content and mean canker length. This study revealed that stem water content in peach trees during winter and frosts is a fundamental factor in infection because it can drastically affect bacteria diffusion in cortical tissues during frost‐ and thaw‐related water soaking. The effect of water content may have important epidemiological consequences firstly due to the influence of several environmental and agronomic factors on tree water content, and then to the prevalence of frost‐related water soaking in many perennial and herbaceous plants.
Study of Genetic Variability Among Monopycnidial and Monopycnidiospore Isolates Derived from Single Pycnidia of Stagonospora ssp. and Septoria tritici with the use of RAPD‐PCR, MP‐PCR and rep‐PCR Techniques
Authors: Czembor P. C. , Arseniuk E. 
Published: March 2003

AbstractThirty‐six isolates of Stagonospora avenae f. sp. triticea, S. nodorum and Septoria tritici recovered from asexual fruiting bodies ‐ pycnidia and their spores were assessed for DNA polymorphism with the use of three molecular techniques: microsatellite‐primed polymerase chain reaction (MP‐PCR), primers correspond to dispersed repetitive elements (rep‐PCR) and random amplified polymorphic DNA (RAPD‐PCR). These polymerase chain reaction (PCR)‐based techniques were simultaneously evaluated for their capacity to detect genetic variation at DNA level. The most polymorphic DNA profiles of monopycnidial and monopycnidiospore isolates were detected with diverse microsatellite motifs used for PCR priming. The lowest similarity values 0.86, 0.76 and 0.84 were identified among monopycnidiospore isolates derived from the same pycnidium of S. avenae f. sp. triticea, S. nodorum and S. tritici, respectively. The above, rather low similarities, found for isolates recovered from single pycnidia, supported a hypothesis that heterokaryosis resulted from high mutation rate of microsatellites and transposons activity. This would have fundamental consequences for the genetic status of asexual populations of Stagonospora spp. and S. tritici. The data produced by this study indicate that more attention should be paid to asexual reproduction as a possible source of genetic variability among populations of the pathogens.
Pathogenicity of Sirodesmin‐deficient Mutants of Phoma lingam
Authors: (†) J. Sock , Hoppe H.‐H. 
Published: March 2003

AbstractSirodesmin‐deficient mutants were produced from aggressive isolates of Phoma lingam by UV‐mutagenesis. The mutation rates were 7.1 × 10‐3 for mutants expressing a 100‐fold reduction of sirodesmin PL in liquid cultures and 1.8 × 10‐3 for mutants with a 1000‐fold reduction. The low ability of the mutants to produce sirodesmins was also apparent in planta after infection of cotyledons or the stem basis of Brassica napus. Growth rates under in vitro conditions, colony morphology, mating types and the formation of pycnidia and asci were not affected by the mutation. The mutants had the same ability as the wild types to infect cotyledons of the susceptible B. napus cv. Lirabon and to cause a typical grey‐green tissue collapse. On the stem basis of the cv. Cobra, however, mutants caused significantly smaller lesions. These results indicate that phytotoxic sirodesmins produced by P. lingam have no basic role in pathogenesis and apparently are not involved in the virulence on cotyledons. However, it cannot be excluded that the compounds act as virulence factors on the stem base of B. napus.
Effect of Metabolic Inhibitors on Red Light‐induced Resistance of Broad Bean (Vicia faba L.) against Botrytis cinerea
Authors: Rahman M. Z. , Honda Y. , Islam S. Z. , Arase S. 
Published: March 2003

AbstractA possible relationship between the synthetic activities of broad bean leaves and red light‐induced resistance against Botrytis cinerea was examined. Both lesion formation and fungal development were suppressed under red light irradiation. In red light‐irradiated leaflets, restricted chocolate lesions were observed only on their inoculated adaxial surfaces, whereas black lesions extended to non‐inoculated abaxial surfaces in the dark. In microscopic studies, clear cell browning was recognized only in red light‐irradiated leaves. Treatment of leaves with an inhibitor of photosynthesis, 3‐(3,4‐dichlorophenyl)‐1,1‐dimethyl urea (DCMU) (25 μm), and an inhibitor of protein synthesis, cycloheximide (25 μg/ml), inhibited the induction of resistance by red light irradiation. Moreover, DCMU‐ and cycloheximide‐treated leaflets produced black necrotic lesions even under red light irradiation for 48 h, which extended to the non‐inoculated abaxial surface. DCMU did not affect fungal growth, spore production or spore germination of B. cinerea. By contrast, cycloheximide at 25 μg/ml suppressed mycelial growth, but not spore production, whereas cycloheximide at the same concentration completely inhibited spore germination. These results suggest that red light‐induced resistance possibly depends on host photosynthesis and protein synthesis.
Application of RAPD‐PCR for Virulence Type Analysis within Verticillium dahliae and V. longisporum
Authors: Zeise K. , Von Tiedemann A. 
Published: March 2003

AbstractA collection of 24 isolates of Verticillium dahliae, 11 isolates of V. longisporum and one isolate of V. albo‐atrum originating from different host plants and geographical regions was tested for genetic variability by random amplified polymorphic DNA‐polymerase chain reaction (RAPD–PCR). Based on nine primers, the three Verticillium species could be clearly differentiated. Likewise, this analysis provided a distinct separation of vegetative compatibility groups (VCG) 2B, 4A and 4B of V. dahliae by specific DNA banding patterns. Additionally, V. longisporum was found to segregate into two subgroups with only 88% similarity. This molecular‐genetic approach was used for the analysis of randomly selected Verticillium isolates from a field with high intensity of oilseed rape cultivation (33% in crop rotation). RAPD‐PCR analysis revealed that 95 of 100 isolates tested belonged to V. longisporum and 5 to VCG 2B of V. dahliae. This study demonstrates an adaptation of Verticillium soil populations to a specific cropping history.
Genetic Diversity Between Botrytis cinerea Isolates from Unstored and Cold Stored Kiwi fruit
Authors: Baraldi E. , Bertolini P. , Chierici E. , Trufelli B. , Luiselli D. 
Published: March 2003

AbstractNinety isolates of Botrytis cinerea collected from kiwi fruit in orchards and in cold storage were compared phenotypically and genetically. The phenotypic characters evaluated were conidia germination, germ tube length and mycelial growth at 0∘ and 20∘C. At 20∘C the two populations showed slight differences but, at 0∘C, isolates from cold storage appeared to grow significantly faster than isolates from orchards. Isolates were then scored with six genetic markers with the aim of investigating population, genetic structure and the mode of reproduction. We detected no genetic differentiation between isolates from orchards and those from cold storage. This suggests that low temperature adaptation of B. cinerea isolates does not have a genetic basis. By contrast, we found great intra‐population genetic diversity, observations suggesting the occurrence of genetic recombination which follows sexual reproduction or alternatively of parasexuality.
Surveys for Beet Necrotic Yellow Vein Virus (the Cause of Rhizomania), other Viruses, and Soil‐borne Fungi Infecting Sugar Beet in Syria
Authors: Mouhanna A. M. , Nasrallah A. , Langen G. , Schlösser E. 
Published: March 2003

AbstractProduction of sugar beet, the most important source of sugar in Syria, has suffered from many problems in the past, especially from diseases. No previous surveys have been made in Syria for viral diseases and soil‐borne fungi of sugar beet. In 1998, samples were collected from plants showing symptoms of virus infection (yellowing, wilting, necrosis and mosaic). Root samples (341) were collected from crops of autumn‐sown seed from 115 localities in seven provinces, 173 root samples from spring‐sown crops and 39 leaf samples were collected during both seasons. The root samples were tested for the presence of viruses by double antibody sandwich‐enzyme‐linked immunosorbent assay (ELISA) and triple antibody sandwich‐ELISA, and for soil‐borne fungi by red plate (Rose Bengal) dishes. We have shown for the first time the presence of Beet necrotic yellow vein virus, Beet soil‐borne virus, Beet yellows virus and Beet mild yellowing virus in Syrian sugar beet fields in which Rhizoctonia sp. and Fusarium sp. were also widely distributed.
Genetic Diversity Among Iranian Isolates of Rhizoctonia solani Kühn Anastomosis Group1 Subgroups Based on Isozyme Analysis and Total Soluble Protein Pattern
Authors: Mohammadi M. , Banihashemi M. , Hedjaroude G.‐A. , Rahimian H. 
Published: March 2003

Abstract Rhizoctonia solani is a destructive fungal pathogen with a wide host range. The R. solani complex species includes several divergent groups delimited by affinities for hyphal anastomosis. In this study, genetic variation among 20 isolates of R. solani anastomosis group 1 (AG1) subgroups (AG1‐IA and AG1‐IB) collected from Mâzandaran province, Iran, and standard isolates of these subgroups, was determined by isozyme analysis and total soluble protein profile. Mycelial protein pattern and isozyme analysis were studied using denaturing and non‐denaturing polyacrylamide gel electrophoresis, respectively. A total of 15 enzyme systems were tested, among which six enzymes including esterase, alkaline phosphatase, superoxide dismutase, octanol dehydrogenase, lactate dehydrogenase and mannitol dehydrogenase generated distinct and reproducible results. The soluble protein patterns were similar among the R. solani isolates examined; however, minor differences in banding pattern were observed between the two subgroups. In isozyme analysis, a total of 64 electrophoretic phenotypes were detected for all six enzymes used. Based on cluster analysis and similarity matrix, the fungal isolates were divided into two genetically distinct groups of I and II consistent with the previously reported AG1‐IA and AG1‐IB subgroups in AG1. Group I represented all isolates belonging to AG1‐IA subgroup, whereas group II represented all isolates belonging to AG1‐IB subgroup. Results from isozyme analysis suggest that the subgrouping concept within AGs is genetically based.
Comparison of Three Different Techniques for Subcutaneous Relocation of the Carotid Artery in Small Ruminants
Authors: Prassinos N. , Raptopoulos D. , Adamama‐Moraitou K. , Galatos A. D. 
Published: March 2003

Three surgical techniques for subcutaneous relocation of the carotid artery in small ruminants are compared. A total of 25 sheep and seven goats were used and randomly assigned to three groups. In group A (technique A), the carotid artery was moved subcutaneously and kept there by suturing the tissues on both sides of the jugular vein beneath the relocated artery and the skin above it. In the other two groups the relocated artery was secured into a skin strip (technique B) or a skin fold (technique C). The animals were used for repeated blood sampling over a period of several months.Technique A did not provide good immobilization whilst among the three, technique B provided the least protection of the relocated artery and was the most difficult to perform. It was concluded that technique C was superior to the other two methods in providing better conditions for long‐term blood sampling.
Periarticular Ossification at the Elbow Joint and Meniscal Ossification in the Stifle Joint of Pigs – Occurrence, Pathomorphology, Breed Differences and Correlations with Osteochondrosis, Leg Weakness and Production Parameters
Authors: JØRGENSEN B. , JENSEN H. E. 
Published: March 2003

SummaryThe occurrence, pathomorphology, and possibly impact of periarticular ossification at the elbow joint and meniscal ossification in the stifle joint are described. A total of 4029 boars of the Landrace and Yorkshire breeds were performance tested and examined radiologically. Periarticular ossification at the elbow joint was found in radiographs at a prevalence of 0.9%. Meniscal ossification was seen as single or multiple foci at the cranial aspect of the joint at a prevalence of 2.6%, and had a bilateral occurrence in 20%. Significant breed differences (P < 0.001) were found for both joint processes. The meniscal ossifications were associated with hindlegs turned out (abduction) (P < 0.001) and stiff locomotion in the rear (P < 0.001), and were negatively (adversely) associated with growth rate (P < 0.01). The periarticular osseous foci were seen as focal firm swellings at the craniomedial aspect of the elbow joint. The meniscal ossifications were observed as single or multiple small, smooth, firm, and irregular swellings in the cranial horn of only the lateral meniscus. The histomorphology of both types of ossifications was similar. Centrally, they were made up by osseous trabeculae. The trabeculae might contain clusters of chondrocytes. Between the trabeculae, which were lined with flat osteoblasts, adipocytes were present. The osseous centre was encircled by mineralized cartilage that blended into more or less fibrous cartilage. However, towards the joint cavity the meniscal ossifications were covered by hyaline cartilage.
Hepatocholangiocellular Carcinoma in a Rat – Case Report
Authors: Teredesai A. , Wöhrmann T. , Schlage W. 
Published: March 2003

SummaryA mixed epithelial tumour in the liver of a 24‐month‐old male Wistar rat from a 30‐month inhalation study is described. The rat, which was in a group exposed to low concentrations of diesel exhaust, was euthanized because of emaciation, forced respiration and abnormal gait. Macroscopic examination of the enlarged liver revealed multiple partly confluent beige‐red nodules up to 1.5 cm in diameter. Small nodules up to 7 mm in diameter were seen in the spleen. Histologically, the tumour nodules in the liver consisted of hepatocellular and cholangiocellular components. The hepatocellular component consisted of moderately differentiated polygonal to round hepatocytes about twice as large as normal hepatocytes and having hyperchromatic, centrally located nuclei with prominent nucleoli and eosinophilic cytoplasm. Foci of haematopoiesis and focal necroses were prominent. The cholangiocellular component was moderately differentiated and consisted of tubular structures lined by low cuboidal to cylindrical cells showing cytoplasmic basophilia and small dark nuclei without prominent nucleoli. The histological features of the nodules in the spleen corresponded to those of the primary tumour in the liver. Based on these criteria, the tumour nodules were diagnosed as hepatocholangiocellular carcinoma. The immunohistological examination confirmed the diagnosis, i.e. immunostaining for cytokeratins was positive for eight and 18 (hepatocellular carcinoma) and for seven and 19 (cholangiocellular carcinoma) as well as for vimentin (dense fibrous stroma). This tumour is considered to be spontaneous because of its single occurrence.
Detection and Identification of Mycoplasma conjunctivae in Infectious Keratoconjunctivitis by PCR. Based on the16S. rRNA. Gene
Authors: Giacometti M. , Nicolet J. , Johansson K.E. , Naglic T. , Degiorgis M.P. , Frey J. 
Published: March 2003

A specific PCR assay based on unique sequences of the rrs genes (16S rRNA) of Mycoplasma conjunctivae was developed for direct detection and identification of this pathogen from clinical material. DNA from eye swabs was amplified after a simple lysis step by either a single PCR with the M. conjunctivae specific primer pair McoR1 and McoF1, or by a nested PCR with the Mycoplasma genus specific primer pair MOLIGEN1‐L and 16UNI‐R in the first step and McoR1 and McoF1 in the second step. The specificity of the primer pair McoR1 and McoF1 was verified with purified DNA from the type strain, from 17 field isolates of M. conjunctivae and from several Mollicutes which are phylogenetically related to M. conjunctivae or which can be isolated from the same host animals. This method identified mycoplasma isolates from goat, sheep, ibex and chamois originating from different countries as M. conjunctivae. No cross amplifications with other mycoplasmas which are related to M. conjunctivae were observed.Eye swab samples containing known numbers of M. conjunctivae cells were analysed after direct lysis of the material. The detection level was estimated to be 20 cells per swab when the nested PCR procedure was used and 2 × 105 by the single PCR method. In an experimental infection model of sheep, the nested PCR method for detection of M. conjunctivae gave results which were comparable to mycoplasmal culture. These are the implications for diagnostic purposes: M. conjunctivae isolates can be identified by the one‐step PCR method, whereas for detection and identification of M. conjunctivae in clinical material the two‐step method should be used (higher sensitivity).
A Combination of Different Polymerase Chain Reaction (PCR) Assays for the Presumptive Identification of Yersinia pestis
Authors: Neubauer H. , Meyer H. , Prior J. , Aleksic S. , Hensel A. , Splettstösser W. 
Published: March 2003

SummaryA combination of four polymerase chain reaction (PCR) assays targeting the Yersinia pestis‐specific plasmoidal genes of the fraction 1 capsular antigen and plasminogen activator/coagulase, the gene of the V antigen of the Yersinia virulence plasmid, and the chromosomal 16S rRNA gene was evaluated for the identification of Y. pestis isolates. All four assays were subjected to the same sample preparation technique, reagents and cycling conditions. Eighteen Y. pestis, 66 Y. pseudotuberculosis, 40 Y. enterocolitica strains, the type strains of the other Yersinia species, and 20 other pathogenic bacterial strains were investigated. By using the proposed combination of PCR assays all Y. pestis strains were identified correctly. The applicability of this combination of PCR assays was demonstrated by the detection of Y. pestis DNA in spiked tissues from Rattus norwegicus and fleas (Xenopsylla cheopis and Ctenocephalides spp.). As little as 60 genome equivalents were detected. This system is applicable for monitoring Y. pestis and its vectors in enzootic natural foci and in the diagnosis of plague in humans and animals.
Diagnosis and Genetic Analysis of Japanese Encephalitis Virus Infected in Horses
Authors: Lian W.‐C. , Liau M.‐Y. , Mao C.‐L. 
Published: March 2003

SummaryNervous disorders were found in two horses and verified as aseptic encephalitis by necropsy in the summer of 2000. To investigate agents that affected the horses, diagnostic procedures involving virus isolation, neutralization test and reverse transcription–polymerase chain reaction (RT‐PCR) were performed. We intracranially inoculated litters of suckling mice with tissues suspected of containing aseptic encephalitis, including cerebrum, cerebellum, brain stem, thalamus, and cerebrospinal fluids; the mice were then observed for 14 days. Neutralizing antibodies against Japanese encephalitis (JE) viruses were present in the cerebrospinal fluid of the horses in titers of 10. Sequences of 500 nucleotides of the premembrane gene of JE virus, synthesized by RT‐PCR, from both the cerebrum and cerebellum were determined. The phylogenetic analysis based on sequences of the premembrane gene revealed a relationship with the JE virus. The divergences at the nucleotide level of 1.2–5.7% and at the amino acid level of 0–4.3% were conserved with other JE strains. The results demonstrated that the pathogens causing equine encephalitis were JE viruses. The strains were closely related to Taiwanese isolates.