bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Comparative Study of Four Viroids of Plants
Authors: Kryczyński S. , Paduch‐Cichal E. 
Published: May 2008

AbstractThe host‐ranges and the reactions of particular plant hosts to inoculation with severe (s‐PSTV) and mild (m‐PSTV) strains of potato spindle tuber viroid, as well as with chrysanthemum stunt viroid (CSV) and cucumber pale fruit viroid (CPFV) were quite similar. Some minor differences did not exceed the limits of differences noted for the strains of the same plant viroid. Two‐directional crossprotection was noted for each viroid pair when s‐PSTV, m‐PSTV, CSV and CPFV were tested on chrysanthemum cv., ‘Bonnie Jean’ plants. Finally, the relative mobility of RNAs of s‐PSTV, m‐PSTV, CSV and CPFV on 5% polyacrylamide gel was identical, no matter what extraction method from plant material was used. We postulate that these four plant viroids may be regardedas the strains of the same plant viroid “species”.On the other hand, chrysanthemum chlorotic mottle viroid (ChCMV) appeared to be a quite different plant pathogen. This viroid infected and caused symptoms only in chrysanthemum plants, and was able to infect and induce symptoms on plants which had already been infected with any other viroid studied, and it did not protect chrysanthemum cv. ‘Bonnie Jean’ plants against any of the other viroids. We were not able to locate a ChCMV‐RNA band on polyacrylamide gel.
Das Verhalten einiger pilzlicher Antagonisten in der Rhizosphäre resistenter und anfälliger Gewächshaustomaten
Authors: Bourbos V. A. , Skoudridakis M. T. 
Published: May 2008

Abstract Action of some fungal antagonists in the rhizosphere of resistant and susceptible tomato plants in the greenhouse The quantitative presence of the rhizospheric mycoflora fungi: Aspergillus alutaceus, Paecilomyces lilacinus, Penicillium herquei, P. nigricans and Trichoderma viride known for its antagonistic action to many pathogens is essentially differentiated in the two cultivars – the sensitive ‘Early pack’ and the resistant to tracheomycosis ‘GC 204′. It seems that the presence of the cultivar ‘GC 204’ favours the growth of these fungi. The first establishment of the fungi Penicillium chrysogenum and P. funiculosum, which are isolated from both cultivars, in the ‘Early pack’ rhizosphere might facilitate the colonization of this zone by the above mentioned antagonist which is not favoured by the sensitive cultivar. Such a changein the rhizospheric mycoflora of the sensitive cultivar may introduce some resistant to soil borne fungi diseases and open new perspectives of the biological control of these diseases.
Detection of Tomato Ringspot Nepovirus and a Clostero‐like Virus in French Hybrid Vidal 256 Grapevines
Authors: Podleckis E. V. , Corbett M. K. 
Published: May 2008

AbstractEight‐ to ten‐year old French hybrid Vidal 256 grapevines in southern Maryland produced berries about one‐third normal size but did not express any obvious leaf symptoms. Electron microscopy of negatively stained tissue‐dip preparations and sectioned material from such vines showed individual and membrane‐associated 28 nm spherical virus‐like particles and closteroviruslike particles. The spherical particles were characterized as an isolate of tomato ringspot virus (TomRSV‐G) that infected a wide range of herbaceous hosts by mechanical inoculation, but did not infect tomato, bean or petunia plants susceptible to the type strain of TomRSV. The closterovirus‐like particles did not react, by immunosorbent electron microscopy, with antisera to grapevine virus A (grapevine stem‐pitting associated virus of Contiet al. 1980) or the 2200 nm Swiss grapevine leafroll closterovirus (Gugleriet al. 1984).
Peroxidase and Poly‐Phenol Oxidase in Brassica juncea Plants Infected with Macrophomina phaseolina (Tassai) Goid. and their Implication in Disease Resistance
Authors: Srivastava S. K. 
Published: May 2008

AbstractStudies on the peroxidase and poly‐phenol oxidase activity in relatively resistant and susceptible strains of Brassica juncea at sequential intervals after inoculation with different isolates of Macrophomina phaseolina revealed that, fungus infected tissues had relatively higher activities of these oxidative enzymes in comparison to healthy plants, and tissues inoculated with ‘Weakly Virulent’ isolates always exhibited higher activity in comparison to ‘Moderately’, ‘Highly’ and ‘MostHighly Virulent’ isolates. At the early stages of the infection on 6th day, resistant plants showed higher activities in comparison to their susceptible counterparts. Very low activity of these enzymes could be recorded in healthy plants. Findings of this, study indicate the possible involvement of these oxidative enzymes in the resistance of this disease.
Squash Mosaic Virus as the Cause of Melon Veinbanding Mosaic in Iran1)
Authors: Izadpanah K. 
Published: May 2008

AbstractMelon veinbanding mosaic, a prevalent disease in the Bushehr Province of Iran, is characterized by formation of green veinbanding in varieties of Cucumis melo L. The disease is caused by an isometric virus of about 30 nm diameter. The virus was purified by acid and neutral pH clarification, polyethylene glycol precipitation and differential and density‐gradient centrifugation. The virus formed three zones in the density‐gradient columns. It reacted with a squash mosaic virus (SqMV) antiserumobtained from the United States in agar‐gel diffusion. Likewise, a U.S. isolate of SqMV reacted with the antiserum prepared against the Iranian isolate. The virus was seed transmissible in snakemelon. This is the first report on the field occurrence ofSqMV in Iran. The Iranian isolate appears to belong to the serotype 1 of SqMV.
A Leaf and Fruit Disease of Pandanus conoideus caused by Erwinia carotovora subsp. carotovora in Papua New Guinea
Authors: Tomlinson D. L. 
Published: May 2008

AbstractA disease of Pandanus conoideus which causes leaf necrosis and fruit rot is reported from Morobe Province of Papua New Guinea. Biochemical, physiological and pathogenicity tests show the causal organism to be a strain of Erwinia carotovora subsp. carotovora. The disease is common on P. conoideus and also affects leaves but not fruit of P. julianettii, another pandanus widely grown in the area.
Detection of Potato Leaf Roll Virus in Intact Sprout Disks by Enzyme‐linked Immunosorbent Assay
Authors: Syller J. 
Published: May 2008

AbstractPotato leaf roll virus (PLRV) was detected by enzyme‐linked immunosorbent assay (ELISA) when intact sprout, stem or leaf tissue disks were substituted for leaf or tuber extracts as test samples. Absorbance (A405) values increased with increasing number of disks per plate well. Readings with sprout disks were significantly higher than those with disks cut from other plant tissues or with tuber sap. A405 values obtained by using 7 or 5 sprout disks per well were near the maximum oneobtained with leaf sap. PLRV was slightly more efficiently detected by ELISA in light sprout disks than in etiolated sprout ones. When ten out of 34 healthy tubers were replaced by PLRV‐infected ones in the tuber indexing test, the diseased samples werereliably detected with 5 etiolated sprout disks per well. The sprout disk sampling technique should be useful for qualitative evaluation of PLRV infection in sprouted potato tubers without necessity to wound them and using sprouts not long enough for maceration.
A Simple Procedure to Detect a dsRNA Associated with Groundnut Rosette
Authors: Breyel E. , Casper R. , Ansa O. A. , Kuhn C. W. , Misari S. M. , Demski J. W. 
Published: May 2008

AbstractA low‐molecular weight double‐stranded (ds) RNA [900 base pairs (bp)] associated with groundnut rosette disease can be used as a diagnostic tool. A simple procedure has been developed that is rapid, reliable, and requires only standard electrophoresis equipment and ultraviolet light for detection of nucleic acid bands. Using this procedure, the dsRNA was detected only in groundnut plants with green rosette of chlorotic rosette symptoms. It was not found in uninoculated groundnut plants, in symptomless groundnut plants with groundnut rosette assistor virus, or in groundnut plants infected with several other known groundnut viruses. In studies with northern blots of extracts from rosette‐diseased and healthy plants, 5′‐endlabeled dsRNA only hybridized to a 900 bp dsRNA from diseased plants. The 900 bp dsRNA was not infectious and its origin remains obscure.
The Development of a Host‐Pathogen System for Evaluating Fusarium Resistance in Early Growth Stages of Wheat
Authors: Miedaner T. 
Published: May 2008

AbstractControlled environment studies revealed significant genetic variation in resistance of wheat seedlings to Fusarium culmorum by using a new developed test system which affords a reproducible inoculation and a precise measurement of the infection rate. A nutrient solution and a conidial suspension in a defined amount are added to agar after autoclaving and the germinated seed are incubated under sterile conditions. With this in vitro‐culture technique F. culmorum infected the whole root system of all tested plants during 12 days and caused significant reduction of root and shoot dry weights. Therefore, escape reactions, depending on the different rapidity of root development, were eliminated. The loss of root dry matter ranged from 12 to 89 %, thus allowing a selection for Fusarium resistance even in the early developmental stages of wheat.
The Smut Fungi of Hyparrhenia hirta (Gramineae)*
Authors: Vanky K. , Deml G. , Oberwinkler F. 
Published: May 2008

AbstractThe following smut fungi reported from Hyparrhenia hirta were studied: Sporisorium andropogonis, S.bardnonense, S. puellare, and S. transfissum. Two new combinations are proposed: Sporisorium barcinonense (Riofrio) Vanky, and S. puellare (H. Sydow) G. Deml. S. andropogonis and S. puellare have morphologically identical spores but differ in the type of spore germination. While S. puellare germinates by a ramified mycelium, S. andropogonis produces four‐celled basidia forming basidiospores laterally and apically. It appears that S. andropogonis is restricted to Dichanthium ischaemum, and S. puellare to Hyparrhenia hirta. S. harcinonense and S. transfissum, both producing the same type of floral infection, are differentiated by their spore measurements.
Small RNAs Originating from Symptomless and Damaged Spruces (Picea abies L., Karst.) II.
Authors: Köster S. , Beuther E. , Riesner D. 
Published: May 2008

AbstractA nucleic acid of about 450 nucleotides, called RNA450, was extracted from needles of symptomless and damaged spruces (Picea abies L., Karst.) and was analysed by two‐dimensional gel electrophoresis. The samples originated from 14‐years‐old spruces of two differently exposed forest sections of the same location in the Hils area. Trees of section 65 were symptomless whereas those of section 103 were retarded in their growth and had partly yellow coloured needles.A new tree was selected for each sampling. Samples were taken at monthly intervals from June 1985 to March 1986, and bimonthly from March to December 1986. The aim of the study is to find out whether the RNA450 indicates the damage of trees in the Hils. The RNA450 was characterized in the accompanying paper (Beutheret al. 1988) as an endogeneous RNA, which is influenced in its concentration by tree damages. A comparison of the RNA patterns of needle extracts from four different needle year classes of symptomless and damaged trees led to the result that the concentration of RNA450 is influenced by season, needle age, and damage. The amplitude of the seasonal changes in the RNA450 level was found to be larger in younger than in older needles and is not influenced by the position of the branch. The period of metabolic activity, as observed on the level of RNA450, is markedly shorter in damaged than in symptomless trees. The usefulness of the RNA450 as a diagnostic test system will be discussed.
A Cucumber Disease Caused by Alternaria alternata and its Control
Authors: Vakalounakis D. J. , Malathrakis N. E. 
Published: May 2008

AbstractA severe leaf spot disease of cucumber caused by a pathotype of Alternaria alternata (Fr.) Keissler was recorded recently in plastic houses in Crete. Lesions ranged in size of a pin point to over 5 cm in diameter, with necrotic tissue on most of their area and a surrounding yellow zone. The pathogen grew satisfactorily on PDA at temperatures between 5 °C–40 °C and spore germination occurred in the range less than 10 °C to over 37 °C. Optimum temperature in both cases was near 26 °C. Of,13 fungicides tested in vitro, sodium omadine, etem, dichlofluanid, captan and folpet were the most inhibitory on spore germination, and iprodione, sodium omadine and dichlofluanid on mycelial growth. Of 25 fungicides applied on two leaf cucumber plants 24 h before inoculation, maneb, etem, dichlofluanid and chlorothalonil were the most effective. When the last fungicides, plus mancozeb, were applied 24 h after inoculation only maneb was effective. In greenhouse experiments, iprodione, prochloraz‐manganese‐complex, chlorothalonil, dichlofluanid, guazatine, maneb and etem were the most effective for disease control, while mancozeb was less effective. The local cucumber cv. Knossos and the Dutch F1 hybrids Evadan, Frella, Herta, Malfa, Mazourka, Pepinex 69 and Renova were all susceptible to infection.
A Strain of Eggplant Mosaic Virus Causing a Severe Disease of Tomato in Argentina
Authors: Gracia Olga , Koenig Renate , Feldman J. M. , Barradas Maria M. 
Published: May 2008

AbstractA virus causing a severe disease of tomatoes in Argentina was identified as a strain of eggplant mosaic virus (EMV). It resembles the type, Abelia latent and various Andean potato latent strains of EMV in its host range and its transmissibility at allow rate by Epitrix sp. It differs from these strains, however, serologically and in some of its cytopathic effects. In serological agar gel double diffusion tests it proved to be closely related to the tomato white necrosis isolate of EMV studied by Barradas (1983) in Brazil.
Isolation of Carnation Ringspot Virus from a Canal Near a Sewage Plant: cDNA Hybridization Analysis, Serology and Cytopathology
Authors: Koenig R. , An D. , Lesemann D.‐E. , Burgermeister W. 
Published: May 2008

AbstractA small water sample of only 60 ml from the Oker Aue canal near Braunschweig was ultracentrifuged. The resuspended pellet was rubbed on Chenopodium quinoa leaves which responded with the formation of almost 200 local lesions. The virus causing these lesions was identified as carnation ringspot virus (CarRSV) by means of dot blot hybridization using random‐primed cDNAs to the viral nucleic acids and by means of serology. Northern blot analysis revealed that the two RNA species of the virus which consisted of c. 3.7 and 1.5 Kb, respectively, have little or no base sequence homology. In immunoelectrophoresis at pH 7.0 the virus migrated towards the cathode. The isometric particles were 33 nm in diameter, round to slightly angular in outline, and showed a distinct granular or knobly surface structure. Virus particles occurred in the cytoplasm, nuclei, and vacuoles of infected cells which in addition contained amorphous granules in the cytoplasm and/or proliferated endoplasmic reticulum. Heavily, affected cells were necrotized and contained large virus particle aggregates which sometimes were crystallized.CarRSV is the third carnation virus, after carnation mottle and carnation Italian ringspot viruses, which was identified in a natural water.
Isolation and Culture of Corn Stunt Spiroplasma in Serum‐Free Medium
Authors: Alivizatos A. S. 
Published: May 2008

AbstractA serum‐free medium (medium A6), supports the primary isolation and cultivation in vitro of corn stunt spiroplasma (CSS). The growth characteristics of CSS in A6 medium are similar to those in the conventional serum dependent, ketoglutarate sorbitol medium (SMK).
Cellulolytic Activity of Three Fusarium culmorum (W. G. Sm.) Sacc. Isolates Pathogenic towards Wheat Seedlings
Authors: Mańka Malgorzata 
Published: May 2008

Abstract Fusarium culmorum isolates pathogenic to wheat (severely, medium and weakly pathogenic) proved to be producers of endo‐1,4‐β‐glucanase and exo‐1,4‐β‐glucanase. The activity of the latter enzyme was low. There was no correlation between the activities in vitro of the two enzymes and pathogenicity of the isolates.
Purification and Electron Microscopy Studies of a Probable Potyvirus from Polianthes tuberosa L.
Authors: Horner MaryB. , Pearson M. N. 
Published: May 2008

AbstractA partial purification procedure is described for a flexuous filamentous virus from leaves of the ornamental crop tuberose (Polianthes tuberosa L.) exhibiting mottle symptoms. Particular problems associated with the purification included particle aggregation and the highly viscous nature of the plant sap. The former difficulty was partially alleviated by the addition of 1.0 M urea to the extraction buffer and the latter by treatment of the extract with cellulase. The mean virus particle length from negatively stained leaf dips was 742 nm (SD = 54) which is characteristic of viruses belonging to the potyvirus group. In addition, electron microscopy of thin sections of infected leaf tissue demonstrated the presence of several types of inclusion bodies similar in appearance to inclusions previously described in association with potyvirus infections in other plants.
Levels of Airborne Botrytis cinerea Conidia Trapped Among Pepper (Capsicum annuum L.) and Eggplant (Solanum melongena L.) Crops Cultivated in Polyethylene Greenhouses on the Málaga Coastal Plain (Southern‐Spain)
Authors: López‐Herrera C. J. 
Published: May 2008

AbstractThe levels of B. cinerea conidia in the air of greenhouses with pepper or eggplant crops at El Morche (Málaga, Spain) were studied during the 1981–82 and 1982–83 growing seasons.The number of conidia collected, the temperatures and relative humidities recorded during different periods were analyzed and fitted to different regression models. Several types of transformation were made to straighten the curves.In both seasons, the regression analyses of the pepper crop data showed no statistical significance, but those for eggplant crops did. The levels of significance for the eggplants were good and those of the 1981–82 experiment were the best.During the 24 h period prior the conidia collection, there was a negative correlation between temperatures measured 6 and 8 h prior to conidia sampling and the number of conidia collected. When the 2nd pair of variables was used, B. cinerea conidia collections were less the longer the periods of temperatures between 20 and 30°C with relative humidities above 70%.This type of information would facilitate a more rational physical and chemical control of the disease in greenhouse vegetable crops to prevent or reduce crop losses.
Pterocarpan Accumulation in Pod Infection‐droplets and Pod Tissues of Phaseolus vulgaris Inoculated with Colletotrichum lindemuthianum1
Authors: Cruickshank I. A. M. , Smith M. M. 
Published: May 2008

AbstractFollowing inoculation of pods of several cultivars of French bean (Red Kidney Selections W 243, 244, 245), with Colletotrichum lindemuthianum (Sacc. & Magn.) Bri. and Cav. ANZ races 1 and 2, phaseollin, phaseollidin and 6‐α‐hydroxyphaseollin were estimated in infection‐droplets and tissue extracts by u.v. spectrophotometry and HPLC. The examples represented both compatible and incompatible cultivar‐race interactions and confirmed a positive correlation between degree of incompatibility andphaseollin concentration or content. The data supported the concept that a phytoalexin index may be of value in selecting for disease resistance or studying the quantitative inheritance of phaseollin in studies of anthracnose resistance in French beans.Concentrations of phaseollidin and 6‐α‐hydroxyphaseollin were low and were not correlated with degree of compatibility of cultivar‐race interactions. The evidence did not support the putative role of 6‐α‐hydroxyphaseollin as an in planta degra, dative phaseollin metabolite associated with French bean –C. lindemuthianum compatible interactions.
Changes in pH and the Production of Organic Acids During Colonization of Tomato Petioles by Botrytis cinerea
Authors: Verhoeff K. , Leeman M. , van Peer R. , Posthuma L. , Schot Nelleke , van Eijk G. W. 
Published: May 2008

AbstractAfter inoculation of petiole stumps of tomato plants with a tomato isolate of B. cinerea, a transition zone between water‐soaked and apparently healthy tissue became clearly visible. Hyphal colonization occurred up to approximately 2 mm beyond this zone. In the colonized tissue the pH values were lower than in the healthy tissue. In the region with most of the tips of the advancing hyphae, however, pH values were slightly, but consistently, higher. In the colonized tissue concentrations of oxalic, citric and succinic acid were higher than in the tissue of healthy, non‐inoculated petioles. In vitro this isolate of B. cinerea produced citric, malic and succinic acid. Oxalic acid, however, could not be detected. In media enriched, with citric or malic acid, mycelial production was higher than in media without this enrichment.
No Evidence of Direct Superoxide Anion Effect in Hypersensitive Death of Pseudomonas syringae Van Hall in Tobacco Leaf Tissue1
Authors: Minardi Paola , Mazzucchi Umberto 
Published: May 2008

AbstractThe hypothesis of superoxide anion generation as a direct bactericidal mechanism exercised by hypersensitive tobacco leaf tissue against an incompatible phytopathogenic pseudomonad was tested.The detection of O2− was made directly by reducing Cytochrome c and by producing nitrite from hydroxylamine chloride and indirectly by measuring the death of endophytic bacteria in the presence of superoxide dismutase.At 4 h and 6 h the low net specific reduction of Cytochrome c in the hypersensitive tissue was not confirmed by the specific production of nitrite. At the same time active superoxide dismutase did not give significant protection to the incompatible bacteria as compared to inactive superoxide dismutase. The protection provided by active superoxide dismutase as compared with the controls (bovine serum albumine treated tissue and non‐treated tissue) at 4 h and at 6 h was not correlated to its superoxide anion scavenger activity.The results indicated that the death of the incompatible pseudomonad during the hypersensitive reaction was not directly linked to O2− generation.
Host Ranges, Serology and Cytopathology of Eggplant and Tomato Strains of Eggplant Severe Mottle Virus, a New Potyvirus from Nigeria
Authors: Ladipo J. L. , Lesemann D.‐E. , Koenig Renate 
Published: May 2008

AbstractTwo potyvirus isolates from the eggplant (Solanum melongena L.) cultivars ‘Ex Benin’ and ‘Ex Jos’, respectively, in Nigeria proved to be almost identical in host range, symptomatology and reactivity with antisera to various potyviruses. In eggplant they caused a severe systemic mottle, blistering and malformation of leaves and an abnormal serration of the leaf margins. A potyvirus isolate from tomato showing mosaic symptoms was similar, but not identical to the eggplant isolates. In the slide, precipitin test the serological differentiation indices were between 1 and 3 for the eggplant and tomato isolates. In the immunoelectron microscopical decoration test all three virus isolates showed some reactivity with antisera to the following potyvir, uses: dioscorea green banding mosaic, groundnut eyespot, a mungbean isolate of peanut stripe, pepper veinal mottle, telfairia mosaic and a tomato isolate from Taiwan. No reactions were observed with antisera to other potyviruses. Cytopathogenic effects w,ere similar for all three isolates in the arrangement of virus particles, the structure of the cylindrical inclusions and the occurrence of clusters of small vesicles. However, other cytological alterations like accumulations of rod‐shaped aggregates of,granular material, formation of giant mitochondria, degeneration of mitochondria and occurrence of a nucleolar inclusion differentiated the isolates.