bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Temperature and Relative Humidity on Germinability of Mucor piriformis Spores
Authors: Bernd Regina B. , Bean G. A. , Conway W. S. , Moline H. E. 
Published: May 2008

AbstractStudies were conducted to determine the influence of temperature and relative humidity (RH) on germinability and viability of Mucor piriformis spores. Spores did not survive when stored at 35 °C and their survival rate decreased rapidly at 30 °C; however, spores remained viable for more than 1 year at 0 °C. RH also significantly affected spore viability. Spores held at 26 °C and 100% RH no longer germinated after 35 days, while those held at 75 or 90% RH germinated for 65 days. At 20 °C, RH had little effect on spore germinability. The effect of temperature and RH on percentage spore germination also varied. At all temperatures studied, spore viability decreased more rapidly with time at 100% RH than at 75 or 90% RH. The least favorable, temperature‐humidity combination, 30 °C and 100% RH, decreased spore germination from 100% to less than 1% in 14 days.
Restriction Digest Patterns of Total DNA from Different Races of Fusarium oxysporum f. sp. pisi– an Improved Method for Race Classification
Authors: Coddington A. , Matthews P. M. , Cullis C. , Smith Karen H. 
Published: May 2008

AbstractSeven isolates of Fusarium oxysporum f. sp. pisi were allocated to either race 2 or race 6 by their ability or inability to cause disease on the six host differentials New Season, New Era, Dark Skin Perfection, WSU 28, WSU 23 and Little Marvel. The isolates showed similar colony morphology on various solid media and their growth rates were inhibited to a similar extent by nystatin, cycloheximide and trichodermin when these compounds were included in potato dextrose agar. Total DNA waspurified from each isolate, digested separately with the restriction endonucleases EcoRI, EcoRV, Pstl, BamHl, SmaI and PvuII and the resulting DNA fragments separated by agarose gel electrophoresis. The patterns obtained were indicative of the presenceof repetitive DNA sequences. Moreover, the patterns obtained for the five race 2 isolates were identical for a given enzyme as were the patterns for the two race 6 isolates. Hence classification of isolates into races by their restrictive enzyme digestion, patterns coincided with that according to pathotypes and could be an improved, more reliable and reproducible method of race classification. An eighth isolate, originally classified as race 1, had lost its ability to cause disease on all six host differentials. The restriction digest patterns of its DNA were different from those of the DNA from both the race 2 and the race 6 isolates.
Auftreten der Blattdürre an Winterweizen (Drechslera tritici‐repentis) in Abhängigkeit von der Fruchtfolge und unter dem Einfluß verschiedener Spritzfolge
Authors: Schmitz H. , Grossmann F. 
Published: May 2008

Abstract Incidence of yellow leaf blotch (Drechslera tritici‐repentis) on winter wheat in dependence on crop rotation and under the influence of different spray programs On winter wheat grown on two experimental fields in different crop rotation programs, a severe incidence of Drechslera tritici‐repentis on the leaves was observed. Monoculture of wheat resulted in a significantly higher attack than growing in rotation with other crops. A distinct relation between different spray programs and disease severity could be found only in isolated cases.
Preparation and Characterization of Membranes from a Coryneform Isolated from Ratoon Stunted Sugarcane
Authors: Oellermann R. A. , Seetal A. , Pillay D. , Roth G. 
Published: May 2008

AbstractMembranes from the coryneform were prepared by an optimized chemical procedure using EDTA and lysozyme and isolated upon equilibrium sucrose density gradient ultracentrifugation. Four bands, I to IV, of peak densities 1.15, 1.19, 1.21 and 1.245 g. cm−3 respectively, were reproducibly obtained. Immunodiffusion of the isolated membrane bands against bacterial antiserum showed that the immunological integrity of the isolated membranes was retained. Membrane bands I and II had similar precipitin arcs having one major component. A shift towards greater immunological complexity in band IV was observed. Similarly, a change in polypeptide composition established by polyacrylamide gel electrophoresis was found. The major group of polypeptides inband I ranging in size from 39 to 67 kdal were successively reduced in bands II, III and IV whereas the polypeptide of 15.7 kdal and of those in the region of 140 kdal showed respective increases. Transmission electron microscopy revealed similar membrane, structures in all membrane bands with only minor differences between them.
Epidemiology of Maize Root Rot in South Africa
Authors: Chambers K. R. 
Published: May 2008

AbstractMaize roots were rapidly infected by soil inhabiting fungi as soon as they differentiated. The first tissues to develop were the seminal roots and mesocotyls. As their function became superseded by that of the adventitious roots, they rapidly became, completely rotted. Adventitious root rot developed slower and the roots did not become as severely rotted. Numerous fungi were isolated from the roots. The most frequently isolated were Helminthosporium pedicellatum and Fusarium moniliforme. Trichoderma sp. was the next most frequently isolated fungus; it was, however, significantly less frequently isolated than the above. Young and Kucharek (1977) found that the fungi isolated from maize roots occur in communities associated with certain plant growth stages. This was not clearly evident in this study. Numbers of root lesion nematodes (Pratylenchus species) correlated non‐significantly with fungus frequencies and root rot.
Changes in the Hill Reaction and the Chlorophyll Fluorescence of Chloroplasts Isolated from Wheat Plants Infected with Stem Rust (Puccinia graminis f. sp. tritici)
Authors: Berghaus R. , Reisener H. J. , Arenz H. , Franck U. F. 
Published: May 2008

AbstractWheat plants with different resistance to stem rust were inoculated with urediospores of Puccinia graminis f. sp. tritici race 32. By means of isolated chloroplasts Hill activity and chlorophyll fluorescence were measured during the first 8–10 days of the infection.Highly resistant cultivars (infection type 0) showed no significant differences in Hill activity whereas resistant (infection type 1) and susceptible plants (infection type 4) exhibited a significant decrease in electron transport. This was associated with an apparent reduction of chlorophyll content. In both the incompatible as well as in the compatible interaction an additional factor had an effect on the inhibition of the Hill activity.Chlorophyll fluorescence was also affected in compatible and in incompatible interactions. However, the two interactions showed different patterns. Whereas the decline in variable fluorescence dominated in resistant varieties, susceptible cultivars showed an additional significant increase in basic fluorescence.The determination of Hill activity and chlorophyll fluorescence demonstrated that photosynthesis was inactivated in different ways in resistant and in susceptible cultivars.
Isolation of Carnation Italian Ringspot Virus from a Creek in a Forested Area South West of Bonn
Authors: Büttner C. , Jacobi V. , Koenig R. 
Published: May 2008

AbstractDuring a survey of plant viruses in small ponds and creeks in a forested area near Bad Münstereifel about 30 km south‐west of Bonn several viruses were isolated. One of these was identified as carnation Italian ringspot virus which previously has been isolated only twice from carnations originating from Italy and USA and which infected carnations only with difficulty. The role of this virus in the forest ecosystem is so far unknown.
Rapid Detection of Potato Spindle Tuber Viroid (PSTV) by Dot Blot Hybridization
Authors: Bernardy M. G. , Jacoli G. G. , Ragetli H. W. J. 
Published: May 2008

AbstractA PSTV probe of 350 bases, prepared in our laboratory, was used to detect picogram quantities of viroids by a simplified, improved, dot blot, hybridization technique in crude potato and tomato extracts. Optimum conditions for certification of PSTV‐free potato plants were established, involving formamide concentration, washing stringencies, exposure time during autoradiography and method of probe radiolabelling. Ten pg of purified PSTV in water and 50 pg of purified PSTV added to healthy plant extract were detected. Also hybridization signals could be detected from as little as 0.075 mg of infected plant tissue.
Influence of Various Factors on Toxicity of Culture Filtrate of a Drechslera maydis Strain from Costus speciosus
Authors: Shukla R. Sajiwan , Husain Akhtar 
Published: May 2008

Abstract Drechslera maydis causing severe leaf blight of Costus speciosus, produced toxic matabolites in vitro. Maximum toxin was produced in modified Fries’ medium if its carbon source was substituted with glucose and nitrogen source with asparagine. Highest toxin accumulation was found at 21 days of incubation and with the initial pH 5.0. The toxin was stable in acidic condition (pH 3.5—7.0) but unstable under alkaline conditions.
A Low Temperature Therapy and Meristem‐Tip Culture for Eliminating four Viroids from Infected Plants
Authors: Paduch‐Cichal E. , Kryczyński S. 
Published: May 2008

AbstractViroid‐free potato and chrysanthemum plants were obtained from meristem‐tips cut from potato spindle tuber viroid‐infected potato plants and from chrysanthemum plants infected with chrysanthemum stunt, chrysanthemum chlorotic mottle or cucumber palefruit viroids after 6 months therapy in a growth chamber at 5 °C and 16 hours daily light of 5.000 lx intensity. Chrysanthemum plants survived quite well the conditions of therapy while potato plants grown from stem cuttings survived these conditions much worse and potato plants grown from tubers did not survive these conditions. PSTV‐free plants were obtained from meristem‐tips cut from sprouts grown from potato tubers infected with severe (s‐PSTV) or mild (m‐PSTV) strains of potato spindle tuber viroid after 6 months therapy at 6–7 °C in the dark. The tubers survived these conditions quite well.The 3 months therapy period was found too short for any plant material. The efficiency of 6 months therapy in viroid elimination varied for different viroids and different plant material from 18.5 to 80.0 %.
Nachweis von Phytophthora fragariae Hickman in Wurzeln der Erdbeerkultursorte ‘Tenira’ mit Hilfe des enzyme‐linked immunosorbent assay (ELISA)
Authors: Werres S. , Casper R. 
Published: May 2008

Abstract Detection of Phytophthora fragariae Hickman in roots of strawberry cultivar ‘Tenira’ by enzyme‐linked immunosorbent assay (ELISA) Phytophthora fragariae Hickman is detected by ELISA in roots of strawberry cv. ‘Tenira’. Because of the high sensitivity of ELISA presence on fungal antigen was demonstrated before symptoms are detected in microscopical investigations.
Hypersensitive Reaction in Petunia
Authors: Nicoud S. , Dumas E. , Gianinazzi S. , White R. F. 
Published: May 2008

AbstractThe hypersensitive reaction of Petunia axillaris cv. ‘M’ to TMV‐SM1 strain is accompanied by the production of 4 unusual proteins in the tissues around the necrotic local lesions.These proteins called d1, d2, d3 and d4, according to their decreasing electrophoretic mobility, are composed of a monomer of either 27,000 d (d2 and d4), 34,500 d (d3) or 20,000 d (d1). They do not appear to be related to the b1 of the PR (b) proteins synthesized by Nicotiana species in response to TMV infection.
Resistenzinduktion gegen systemische Virusinfektionen durch Kulturfiltrate von Stachybotrys chartarum (Ehrenb. ex Link) Hughes
Authors: Maiss E. 
Published: May 2008

Abstract Induced resistance in systemic host‐virus combinations by culture filtrates of Stachybotrys chartarum (Ehrenb. ex Link) Hughes Culture filtrates of the fungus Stachybotrys chartarum sprayed on systemic hosts decreased the development of symptoms of different elongated and isometric viruses. The degree of induced resistance depended on the host‐virus system. An interval of three or five days between application of the filtrate and virus inoculation was sufficient to induce resistance. High inoculum concentration reduced the efficiency of induced resistance in cucumber against CMV. The content of CMV in inoculated andsystemically infected, induced resistant cucumber leaves was decreased. TMV inoculated leaves of induced resistant tobacco plants contained higher, systemically infected leaves lower virus amounts as comparable untreated control leaves. Reduced virus content and distribution in induced resistant plants obviously resulted from inhibition of multiplication and spread of viruses.
Attack of Didymella bryoniae on Roots of Cucumber
Authors: Thinggaard Kirsten 
Published: May 2008

Abstract Didymella bryoniae is very common in cucumber crops grown in Danish glasshouses and is able to attack all aerial parts of the plant. In October 1984 an attack of D. bryoniae on cucumber roots was observed for the first time. Some of the roots were dark because of pseudothecia containing asci. This fact may have importance for the spread and survival of the disease and for its control.
Geographic Variation of Esterase Isozymes in Populations of Alternaria mali on Apple Leaves
Authors: Hwang Byung Kook , Yun Ju Ho , Kim Zin Suh 
Published: May 2008

AbstractThe 500 monoconidial isolates of Alternaria mali occurring in different locations, Suweon, Cheongju, Kochang, Daegu and Jinju, Korea, in 1983 were used to examine geographic variation of esterase isozymes. The electrophoretic patterns of esterases were qualitatively and quantitatively different between isolates. The 14 different bands were detected on the basis of the decreasing electrophoretical mobility, although all bands were not present in any of the isolates. A comparison of the frequency of esterase isozymes at different bands showed marked variations among the geographic locations. The geographic distance between A. mali populations did not correlate strongly with divergence in esterase isozymes, whereas A. mali populations within a geographic feature were more closely related than populations separated by a mountain range.
Antagonism of Rhizoctonia spp. to Pythium oligandrum and Damping‐Off Fungi
Authors: Walther D. , Gindrat D. 
Published: May 2008

AbstractIn paired cultures on corn‐meal agar, Rhizoctonia solani, R. cerealis and R. fragariae caused vacuolation, disappearance of cytoplasm, and apparent lysis of hyphae of Pythium oligandrum, P. ultimum, and Aphanomyces cochlioides. Hyphae of Phoma betae were not injured by the Rhizoctonia spp. When sugar‐beet seeds dressed with mycelium of R. cerealis, R. fragariae, or an isolate of R. solani nonpathogenic to sugar‐beet were planted in soil naturally infested with P. ul‐timum, the level of biological control of damping‐off was similar to that obtained with captan dressing. In soil artificially infested with P. ultimum, biological dressings were slightly less efficacious than the chemical dressing.
Befall‐Schaden‐Relationen für das Wirt‐Parasit‐Paar Weizen‐Septoria nodorum Berk.
Authors: Kelaniyangoda D. B. 
Published: May 2008

Abstract Infestation‐damage relationship for the host‐parasite system wheat‐Septoria nodorum Berk. It was the aim of these investigations to elucidate the relationship between infestation by Septoria nodorum Berk. and the damage caused thereby to the winter wheat varieties grown in the GDR. In 1983 and 1984 the varieties Alcedo and Taras were tested, and for the identification of typical varietal reactions, another 4 cultivars (Arkos, Compal, Mironovskaya 808 und Ilyitshovka) were included, in 1984.Artificial inoculation was carried out when the ears were emerging, using spore suspensions of varying density to achieve various degrees of infestation. For each variety, ear and flag leaf infestations were recorded on 800 culms and these were thengrouped into the categories I, II and III according to the number of points they had received (9 = without any infestation, 7 and 5 = number of points decreasing as infestation increased). Altogether 5–6 assessments were made, with the points given at the growth stage “beginning of the milky ripeness” being used as the basis for the calculation of the infestation‐damage relationship. The most important criterion for each group was the mean single ear weight, the 1000‐grain weight and the number of grains per ear, were also taken into consideration.Comparing ear infestation with yield it can be stated that the variety Compal and the early ripening Soviet varieties Mironovskaya 808 and Ilyitshovka showed relatively low losses. The variety Taras ranked in the middle. Alcedo and Arkos suffered the highest yield losses. Depending on the variety, an infestation level rated with 7 points at the beginning of milky ripeness implied yield losses of 5–13 %, whereas a 5 rating point would represent losses of 13–23 %.The results obtained make it clear that the wheat cultivars tested were not damaged by S. nodorum to the same degree, indicating differing varietal susceptibility, which does not allow a generalization with respect to the infestation‐damage relationship for the host‐parasite pair wheat‐S. nodorum.
Studies on the Extracellular Polysaccharides (EPS) Produced in vitro by Pseudomonas phaseolicola III. Kinetics of Levan and Alginate Formation in Batch Culture and Demonstration of Levansucrase Activity in Crude EPS
Authors: Gross M. , Rudolph K. 
Published: May 2008

AbstractIn batch culture Pseudomonas phaseolicola converted ca. 8–11% of the substrate (sucrose) into extracellular polysaccharides (EPS). The percentage of conversion was independent of the concentration of sucrose in the medium. However, the increase of total EPS observed with enhanced substrate concentration was largely due to a drastic stimulation of the levan produced. Production of alginate, in contrast, was stimulated to a much lower extent. EPS production was highest during the middle phaseof exponential growth and gradually terminated as the cultures grew older. With sucrose as substrate, the formation of alginate followed the levan synthesis. With glucose or gluconate, however, there was no production of levan, and the alginate synthesis, started immediately after the lag‐phase of the culture.Levansucrase activity was detected in the protein fraction of crude EPS produced by a culture grown in sucrose containing medium. Enzyme activity was demonstrated both by the release of glucose and the formation of levan from sucrose. Upon ion exchange chromatography on DEAE‐fractogel levansucrase behaved as a rather acidic protein. Native polyacrylamide gel electrophoresis of the enzyme fraction revealed a major band with an apparent molecular weight of ca. 68,000 d. Several grams of levan were synthesized with a partly purified enzyme preparation in the absence of bacteria.
Grapevine Fanleaf Virus Monoclonal Antibodies: their Use to Distinguish Different Isolates
Authors: Huss Brigitte , Muller Sylviane , Sommermeyer Ghislaine , Walter B. , Van Regenmortel M. H. V. 
Published: May 2008

AbstractMonoclonal antibodies (MCAs) specific for Grapevine Fanleaf Virus (GFV) were obtained by fusion of a non‐secreting myeloma cell line with the spleen cells from Balb/c mice immunized with GFV isolate F 13. The MCAs were tested with apanel of GFV isolates, using both crude extracts and purified virus particles.Some of the MCAs recognize all 41 isolates tested and are suitable as a diagnostic reagent for GFV detection. Certain MCAs do not bind to some of the isolates, while others show a lower reactivity for certain isolates than for the immunogen F 13. MCAs make it possible to distinguish GFV isolates which until now could not be distinguished by using polyclonal antiserum.
Effects of Disease Intensity and Application Type on Efficacy and Synergy of Fungicide Mixtures Against Phytophthora infestans
Authors: Samoucha Y. , Hugelshofer U. , Gisi U. 
Published: May 2008

AbstractOf eleven tomato cultivars ‘Baby’ was the most susceptible to Phytophthora infestans. The sporangium concentration of the fungus and the methods of fungicide application had a significant effect on the efficacy of oxadixyl, mancozeb and cymoxanil when tested singly or in mixture against sensitive and phenylamide resistant strains of P. infestans on tomato. Mancozeb was the least effective fungicide, its activity decreased significantly with increasing numbers of sporangia used for inoculation (increasing disease pressure) and its efficacy was dependent on the method of application. Oxadixyl and cymoxanil showed much stronger antifungal activities (except oxadixyl against resistant strains) which did not depend on the number of sporangia or method of fungicide application. The mixture of oxadixyl, mancozeb and cymoxanil was equally active and was independent of application type, sporangium concentration and level of sensitivity of the fungus. Mixtures of the single components showed synergistic interactions up to levels of 20, depending on the activity of the individual fungicide and the different disease intensities. Three‐way mixtures containing oxadixyl, mancozeb, and cymoxanil represent therefore promising possibilities in practice for strong disease pressure, even when resistance problems are expected.
Transfer of Alternaria macrospora from Cotton Seed to Seedling: Light and Scanning Electron Microscopy of Colonization
Authors: Bashan Yoav , Levanony Hanna 
Published: May 2008

Abstract Alternaria macrospora is transferred from an infected seed, through the plant stem to the cotyledon and sporulates on its surface. However, at the beginning of the process, there is no difference between resistant and susceptible plants. In later stages, lower levels of fungal mycelium and sporulation were detected on the seedlings of a resistant cultivar. The fungus grew inside the plant from the underground to the upper parts. The mycelia which originated from surface spores could penetrate, through stomata and result in leaf colonization. A. macrospora sporulated ultimately on plant surfaces whereas the internal leaf tissue was colonized by mycelium only. This study suggests that cotyledon infection is a result of seed infection.
Lack of Involvement of Nutrients in the Latency of Alternaria alternata in Unripe Mango Fruits
Authors: Droby S. , Jacoby B. , Prusky D. 
Published: May 2008

AbstractThe possible relation between changes in mango fruit composition during ripening and the latency of Alternaria alternata infections was investigated. The main increase in total soluble solids and the decrease in acid content in ripening mangofruits occurred during the initial 13 days after harvest, while symptoms of A. alternata appeared only 5 days later. Susceptibility of resistant peeled mango fruits flesh could not be increased by infiltration with sucrose, at a concentration that sustains maximal growth in vitro.
A Naturally Occurring Resistant Forma Specialis of Phytophthora drechsleri to Metalaxyl
Authors: Chauhan V. B. , Singh U. P. 
Published: May 2008

AbstractMetalaxyl was assayed in vitro against six species or formae speciales of Phytophthora. The ED50 values of metalaxyl for P. drechsleri, P. drechsleri, P. megasperma f. sp. medicaginis, P. megasperma f. sp. glycinae, P. boehmeriae, P. citricola and P. drechsleri f. sp. cajani ranged from 0.09–19.00 μg ml−1. The values for P. citricola and P. drechsleri f. sp. cajani were 6.45 and approximately 19.0 μg ml−,1. The ED90 values of all the species or forma speciales ranged from 0.9 to 199.0 μg ml−1. The ED90 for P. citricola and P. drechsleri f. sp. cajani was 48 and 199 μg ml−1, respectively. <P. drechsleri f. sp. cajani appears to be a naturally resistant forma specialis against metalaxyl.