bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects of Polyacrylic Acid, Acetylsalicylic Acid and Salicylic Acid on Resistance of Cucumber to Colletotrichum lagenarium
Authors: Mills P. R. , Wood R. K. S. 
Published: May 2008

AbstractInjection of cucumber cotyledons with polyacrylic acid (PA), acetylsalicylic acid (ASA) and salicylic acid (SA) induced resistance to inoculations with Colletrichum Iagenarium when inoculation followed injection by 96 h but not by 24 h. Size and number of lesions were greatly decreased. Resistance was greatest in injected cotyledons but was also pronounced in non‐injected halves of cotyledons and occasionally in first or second leaves.Incorporation of PA, ASA and SA into liquid shake cultures did not significantly affect growth of the pathogen.Gel electrophoresis of soluble proteins extracted from cotyledons showed that induction of resistance was not accompanied by the appearance of novel soluble proteins.
Effect of the Compound CGA 78039 and Streptomycin on the Expression of Bacterial Stem Rot in Dieffenbachia
Authors: Vantomme R. , Swings J. , Calus A. , Van Luchene I. , de Ley J. 
Published: May 2008

AbstractBacterial stem rot, due to Erwinia chrysanthemi, is a serious problem in ornamental crop protection, e.g. in Dieffenbachia. It was our aim to compare the effect of the synthetic compound CGA 78039 and streptomycin sulphate on the suppression of stem rot disease in Dieffenbachia. Different treatments were applied under natural and artificial infection pressures. Pretreatment of the mother plants with CGA 78039, followed by dipping of the cuttings overnight in the same solution before potting and five subsequent weekly foliar sprays during growth reduced the expression of stem rot in Dieffenbachia significantly.
Survival in the Field of Pseudomonas cichorii (Swingle) Stapp, Causal Agent of Lettuce Varnish Spot*)
Authors: Bazzi C. , Piazza C. , Mazzucchi U. 
Published: May 2008

AbstractThe survival in the field of P. cichorii was studied using a twice‐marked mutant resistant to 200 μg/ml of both nalidixic acid and rifampicin. The mutant was used to contaminate head lettuce cv. Verpia in an experimental field. The survival of P. cichorii was evaluated on the basis of the results of quantitative reisolations, on appropriate selective medium, form asymptomatic leaves, nerval lesions, surface debris and soil after the debris had been incorporated. The mutant was found on symptomless leaves up to 63 days after contamination. It cannot be concluded that P. cichorii is a resident epiphyte because the mutant was already found associated with nerval lesions only 28 days after field contamination.The mutant was successfully reisolated from the lettuce debris, but not form the soil after its incorporation. 115 days after incorporation of the debris the mutant was found associated with nerval lesions in lettuces planted the following year in the same field.The means by which P. cichorii survives are discussed. Experimental evidence indicates that it survives in the soil, associated with infected lettuce debris, but that the population level was below the sensitivity threshold of the detection method.
Mechanische Verletzung des Plasmalemmas als mögliche Voraussetzunlg Für die Virsinfektion von Pflanzen
Authors: Hein A. 
Published: May 2008

Abstract Mechanical injury of the plasmalemma As a possible pre requisite for virus infection of plants A basic requirement of the infection in case of mechanical inoculation f viruses could be that the plasmalemma of cells is to be injured, for a clearance between cell wall and plasmalemma at the time of inoculation in cells, which are suitable for primary infection prevented the infection.By means of the hypertonic concentration of 0.7 mol/l of the plasmolytica ethylenglycol, sucrose, glucose, sorbitol and mannitol, which permeate with different speeds, and by modifications of the mannitol treatment, a withdrawal of the plasmalemma to varied distances from the cell wall was induced in cell of the upper side of leaf disk from Nicotiana glutinosa and N tabacum“samsun” This could be observed microscopically in the leaf disks after embedding in liquid paraffinTreated leaf disk were inoculated with tobacco mosaic virus and incubated floating on tap waterThe infection rate, determined by the number of local lesions in case of leaf disks from Nicotiana glutinosa and by the extractable infectivity in case of “Samsun”proved to be dependent on the degree of withdrawal of the plasmalemma from the wall of cell of the upper disk side A strong withdrawal by rounding of the protoplasts in all or almost all cells, caused by the non permeating mannitol or sorbitol, did hardly permit infection
Stoffwechsel phenolischer Verbindungen in gesunden und Braunrost‐infizierten Gersten‐ und Weizenvarietäten
Authors: Harms H. , Terbea Maria 
Published: May 2008

Abstract Metabolism of phenolic compounds in healthy and brown rust‐infected barley and wheat varieties Infections with Puccinia isolates cause an accumulation of phenolic compounds both in resistant and susceptible isogenic lines of barley and wheat seedlings. The increased de novo biosynthesis of hydroxy‐cinnamic and ‐benzoic acids is catalysed by the enzyme phenylalanine‐ammonia‐lyase (PAL) whose activity seems to be controlled not only by the substrate (phenylalanine) but also by the formed products (phenols). Depending on its actual physiological state every plant species shows as a reaction upon infection a typical behaviour. It is remarkable that healthy and rust‐infected plants contain the same percentage of individual phenolic acids. An infection does not lead to an increase of individual hydroxycinnamic‐ or benzoic acids. There are only differences in quantity but no differences in quality. The pattern of phenolic acids seems to be largely genetically determined and formed according to the developmental stage of the plants. The hydroxycinnamic and ‐benzoic acids formed during the host‐parasit‐interactions seem to be, at least for the analysed combinations, more the consequence than the cause of resistance.
Phytotoxic Activity of Tenuazonic Acid Isolated from Alternaria alternata (Fr.) Keissler Causing Leaf Blight of Datura innoxia Mill. and its Effect on Host Metabolism
Authors: Janardhanan K. K. , Husain Akhtar 
Published: May 2008

AbstractTenuazonic acid isolated from Alternaria alternata (Fr.) Keissler causing leaf blight of Datura innoxia Mill. showed significant phytotoxic activity when tested on monocot and dicotyledonous plants. The toxin induced chlorosis and necrosis on leaves of D. in noxia, D. stramonium, D. metel, belladonna, cowpea, wheat, rye, cabbage, cauliflower and maize at 200μg/ml and wilting of seedlings of D. innoxia at 100μg/ml concentration. It also caused complete inhibition of root and shoot elongation of germinating seeds of D. innoxia, wheat, rye, green gram and lettuce at 100μg/ml concentration. It was a nonspecific phytoxin and appeared to have significant role during pathogenesis.Tenuazonic acid did not cause any significant change in the rate of respiration and in sugar, carbohydrate, total phenol and nitrogen contents of D. innoxia leaves. But its treatment on host plant induced 64 % reduction of chlorophyll content in leaves after 72 hours and 40 % reduction in protein content after 24 hours.
Die Isolierung bodenbewohnender Feinde des Maisbranderregers Ustilago maydis
Authors: Geyer A. , Schnürlein‐Land G. , Beiderbeck R. 
Published: May 2008

AbstractThe Isolation of Soil‐Inhabiting Enemies of Ustilago maydisUsing sporidial lawns of Ustilago maydis in water agar layers as indicator plates 2 organisms could be isolated from soil samples which produce plaques. These organisms were identified as Acanthamoeba polyphaga and Myxococcus spp. Both organisms control populations of Ustilago maydis in sterile soil too.The isolation method may be gainfully used in the search for further organisms with more specific potential for the biological control of Ustilago maydis.
Occurrence of Tobacco Necrosis Virus in Strawberry Cultivars and Frageria vesca Indicators
Authors: Tanne Edna 
Published: May 2008

AbstractTobacco necrosis virus (TNV) was found occasionally in roots of indicator plants such as UC‐4, UC‐5 and alpine, commonly used for screening of strawberry virus diseases. The virus was purified and identified as TNV by its host‐range, physical properties, electron microscopy and serological tests. The implication of the possible occurrence of TNV in indicator plants on reliable diagnosis of virus disease in strawberry is discussed.
Der Einfluß von Infektionen mit dem Kartoffel‐X‐Virus und Behandlung mit der antiphytoviralen Substanz 2,4‐Dioxohexahydro‐1,3,5‐triazin auf die Bildung und den Apikaltransport 14C‐markierter Assimilate und die Konzentration freier Aminosäuren
Authors: Schuster G. , Sölter Barbara , Byhan O. 
Published: May 2008

Abstract The influence of infections with potato virus X and treatment with the antiphytoviral substance 2,4‐dioxohexahydro‐1,3,5‐triazine on the formation and the apical transport of 14C‐labeled assimilates and on the concentration of free amino acids After two hours of exposure of lower leaves of Nicotiana tabacum L. 'Samsun’to an air containing 15.91 MBq 14CO2 per liter of air, the bulk of the activity of assimilated 14CO2 was found in glucose. Lower activities at different RF values were obviously assignable to intermediates of photosynthesis. Saccharose was not labeled. Infections with potato virus X (PVX) resulted in the incorporation of 14CO2 into the assimilates being reduced by about 28 %, but the relative proportion of apically transported labeled assimilates in virus‐infected plants was only insignificantly diminished compared with that in healthy plants. Treatment with the antiphytoviral compound 2,4‐dioxohexahydro‐1,3,5‐ triazine (DHT = 5‐azadihydrouracil) had no appreciable effect upon 14CO2 incorporation of healthy plants. By contrast, 14CO2 incorporation into assimilates was greatly increased by DHT in the case of virus‐infected plants, now reaching values that exceeded those of healthy plants receiving no treatment. The main reason for this is seen in the great reduction in the concentration of PVX and, consequently, in the virus‐induced reduction of photosynthesis. Apical transport of assimilates from exposed leaves was substantially reduced, after treatment with DHT, in healthy as well as in virus‐infected plants. Obviously, the afraction of by older leaves exposed to 14CO2 has been increased by cytoKinin activities of DHT to such an extent that the source‐to‐sink conditions influencing the intensity of phloem transport have been substantially changed. The pattern of detected free ammino acids had, in the leaves exposed to 14CO2 been expanded, after infection with PVX, by histidine and phenylalanine. In the apical leaves, in which a larger number of free amino acids had been detected than in the lower leaves exposed to 14CO2, there was also observed an additional occurrence of phenylalanine in plants infected with PVX, whereas two not specified amino acids disappeared. Treatment with DHT did not change the amino acid pattern of healthy control plants. In plants infected with PVX, DHT had the effect of canceling virus‐induced variations in the amino acid pattern (one exception being phenylalanine in apically inserted leaves). Evidently, this was brought about indirectly by strong inhibition of virus replication and, consequently, by elimination of virus‐induced variations.
Transmission of Alternaria macrospora in Cotton Seeds
Authors: Bashan Yoav 
Published: May 2008

Abstract Alternaria macrospora was isolated from seeds only after the natural opening of the bolls and exposure of seeds to an environment in which the fungus was present. The fungus lacks the ability to penetrate the boll wall and reach the seed site. Attempts to isolate the pathogen from seeds of immature bolls at different developmental stages failed. Internal infection by slow injection resulted in seed infection and partial shedding of the injected plant parts which was high in buds and decreased with the ripening to mature bolls. Severity of seed infection was not dependent on either inoculum level, boll physiological age or even if the boll itself was not diseased. Infection of flowers under field conditions caused flower shedding. Naturally infected seeds or inoculated seeds with inoculum levels of 100 spores/ml and above resulted in diseased cotyledons, the incidence of which was, for inoculated seeds, positively correlated with inoculum level. A small difference was observed between cultivars in susceptibility to artificial inoculation at the cotyledon stage. A. macrospora survived on commercial cotton seeds and on post‐season plants left growing at the field edges. Survival in plant debris under field conditions was minimal and may only have a minor effect on field reinfestation.
Effect of Alfalfa Wilts on the Hydroxyproline Content in Cell Wall
Authors: Krátká J. , Kůdela V. 
Published: May 2008

AbstractThe Hyp content was studied in cell wall of alfalfa susceptible and resistant strains on the 3rd, the 7th and on the 14th day after inoculation with Verticillium albo‐atrum or Corynebacterium michiganense pv. insidiosum. The changes of Hyp content after inoculation with both pathogens were markedly expressed in alfalfa roots.Resistant plants of R 337 strain responded to inoculation with V. albo‐atrum or C. michiganense pv. insidiosum by the decrease of Hyp content mainly on the 3rd and on the 7th day. On the 14th day after inoculation Hyp content practically did not differ from that of the control. Susceptible plants of S 354 and S 321 srains responded to inoculation with wilt pathogens by the slight decrease of Hyp content at the 3rd day after inoculation. A significant increase of Hyp content was found on the 7th and mainly on the 14th day after inoculation in comparison with control plants.The cell wall Hyp content was also determined with 7 R‐strains and 7 S‐strains at 120 days after inoculation with both pathogens. In each R and S strain two categories of plants were used for chemical analyses: Wilt‐free plants (0 to 1 classes) and diseased, wilted plants (2 to 6 classes). In the resistant alfalfa strains no differences in Hyp content between the wilt‐free and diseased plants were found. In the susceptible alfalfa strains the Hyp content was significantly higher in roots of diseased plants comparing with the wilt‐free ones.Only negligible changes in Hyp content were registered in the overground parts of all inoculated alfalfa strains.
Etiology and Epidemiological Observations of Elaeagnus Leaf Spot Caused by Septoria elaeagni
Authors: Lorenzini G. , Vannagci G. , Triolo E. 
Published: May 2008

AbstractA foliar disease, causing necrotic spots and severe defoliation of Elaeagnus angustifolia, was detected in Tuscany, Italy, in 1979. The causal agent was identified as Septoria elaeagni. It was not pathogen to E. umbellata, E. pungens, E. multiflorum, and Hippophae rhamnoides.Ultrafiltrates from liquid cultures showed toxicity against E. angustifolia and some herbaceous species, non hosts of the pathogen.Disease was significantly more severe in an overhead irrigation system than when water was delivered to the soil alone.
Cross‐Protection and Multiplication of Mild and Severe Strains of TMV in Tomato Plants
Authors: Burgyán J. , Gáborjányi R. 
Published: May 2008

AbstractThe presence of virus having mixed coats has been demonstrated serologically in tomato plants cross‐protected with a mild strain (M 11–16) against the severe (UI) strain of tobacco mosaic virus (TMV). The proportion of virus having mixed coats remained constant throughout at ca. 40% even in top leaves where severe symptoms caused by the challenge virus (U1) first appeared.The symptoms caused by the U1 in doubly‐inoculated plants occurred in the leaves where:

the amout of total virus (irrespective of the type of coat) protein was 52% that of U1 strain in singly inoculated plants,
the multiplication of the severe U1 strain was reduced to only 9% as compared with the leaves singly inoculated with U1,
the ratio of severe to mild strain was increased to near equality although there was a significant reduction in the multiplication of U1in these leaves,
the amount of infective U1RNA started to increase.
Ultrastructure of Soybean Leaf Cells Infected with Cowpea Mild Mottle Virus
Authors: Thongmeearkom P. , Honda Y. , Iwaki M. , Deema N. 
Published: May 2008

AbstractCowpea mild mottle virus (CMMV), a whitefly‐transmitted, rod‐shaped virus isolated in Thailand, induced feather‐like structures in the cytoplasm of infected soybean cells. These structures were the results of a complex arrangement of virus particles and occurred in all types of cells observed. An organized arrangement of virus particles in the form of layers was also observed in the cytoplasm of the infected cells. In ultrathin sections, the particles measured about 10 nm wide and more than 600 nm long, which corresponded to the size reported for the purified preparations of CMMV. No feather‐like structures or virus particles were observed in the comparable healthy tissues.
The Antimicrobial Efficiency of Root Oil Against Human Pathogenic Bacteria and Phytopathogenic Fungi
Authors: Jaiswal Ku , Batra Ku. Anita , Mehta B. K. 
Published: May 2008

AbstractThe in vitro antimierobial activity of root oil of C. orchioides were studied against human pathogenic bacteria and phytopathogenic fungi by comparing the results with standard microbial susceptibility testing biodises. The oil of C. orchioides in case of bacteria shows significant activity against Bacillus anthracis, B. subtilis, Salmonella pullorum, S. newport, and Staph. aureus. While in case of fungi root oil had excellent activity against Fusarium monili forme, F. solani, Asprgullus flavus and Cladosporium and shows significant activity against all other tested fungi.
Vorkommen von Tobacco Rattle‐Virus in Roggen (Secale cereale) in der Bundesrepublik Deutschland
Authors: Huth W. , Lesemann D.‐E. 
Published: May 2008

Abstract Natural occurrence of tobacco rattle virus in rye (Secale cereale) in the Federal Republic of Germany Near Bergen/Dumme in northern Germany, in an area known for the occurrence of tobacco rattle virus (TRV) on potatoes, 5–10 % of rye plants of one experimental plot were severely stunted and showed distinct chlorotic mottling of leaves. In these plants TRV was identified on the basis of particle morphology and serology (Immunoelectron microscopy and ELISA). TRV was also detected in Capsella bursa‐pastoris and Stellaria media from an area adjacent to the rye plot but not in nearby commercial rye fields.
Effect of Micronutrients on the Development of Bacterial Blight of Rice
Authors: Philip R. , Devadath S. 
Published: May 2008

AbstractDiferent concentrations of miceonutrients (with one exception; Table 1) increased the degree of attack on rice plants by Xanthomonas oryzae. When a double dose of Mn or Cu was applied or when Mn was omitted, length of lesions was considerably smaller than with all micronutrients on normal concentration. No correlation was found between total phenols, total sugars, reducing sugars, non‐reducing sugars, amino acids, and total nitrogen and lesion development in different micronutrients combinations.
Infections of Jute, Maize and Rice ot Revealed by the Standard Blotter Method of Seed Health Testing
Authors: Michail S. H. , Mathur S.B. , Neergaard P. 
Published: May 2008

AbstractIn the standard blotter seed health testing of jute, maize and rice some ungerminated seeds, and seedlings with or without symptoms were eventually found to be infected by pathogenic fungi on prolonged incubation any by trans‐planting seedlings from blotters to autoclaved soil in pots.
Multiplication of Pseudomonas syringae pv. phaseolicola“in planta”
Authors: Rudolph K. , Mendgen K. 
Published: May 2008

AbstractIn the compatible combination of the halo blight disease of bean Pseudomonas phaseolicola was able to colonize large areas of the intercellular space of leaves, such that these confluent water congested areas became visible as water‐soaked spots. Most of the plant cell walls in the infected region maintained their normal shape, even when the cytoplasm had collapsed. Some inward bending of plant cell walls preceded their rather slow degradation and final replacement by bacterial masses. Neighbouring plant cells appeared to be metabolically active.In resistant leaves no indications of active bacterial attachment or encapsulation could be observed. However, bacteria appeared to be more densely packed in resistant leaves, and relatively more plant cells completely collapsed as compared with susceptible leaves.From 8—14 days after inoculation, the bacterial concentration did not change much in susceptible or resistant leaves, indicating the absence of bactericidal components. Even Pseudomonas pisi snowed some multiplication in bean leaves (immune reaction), but its growth stopped earlier than that of P. phaseolicola. in the resistant cultivars, probably due to a different mechanism of resistance. Although less bacteria were determined in the intercellular washing fluid (IF) compared with leaf homogenates, the high bacterial concentrations in the IF supported our observation that an effective encapsulation of bacteria in resistant leaves did not occur.
Slow Rusting of Wheat to Puccinia recondita
Authors: Poyntz B. , Hyde P. M. 
Published: May 2008

AbstractSeven cultivars of winter wheat were studied in field trials to determine their level of slow rusting ability towards brown rust. Cv. Bouquet was the most resistant, with greatly reduced infection levels, areas under die disease progress curve and infection rate compared with those measured on the control cv. Armadda. Cultivars Atou and Maris Freeman also showed evidence of slow rusting, but the responses of cultivars Waggoner and Flinor were not consistent in successive trials. Cv. Flanders appeared to be almost as susceptible as cv. Armada. The use of the Gompertz transformation of desease progress data for the calculation of apparent infection rates allowed better comparison of rates between cultivars than when the logistic transformation was used.
Studies on Induced Resistance to Tobacco Mosaic Virus, in Samsun NN Tobacco and Changes in Ribosomal Fractions
Authors: Stein A. , Spiegel S. , Loebenstein G. 
Published: May 2008

AbstractResistance to tobacco mosaic virus (TMV) was activated by various forms of induction in Samsun NN tobacco leaves, and the intensity of the different forms was compared. Induced resistance was highest in leaf tissue between TMV inoculated stripes parallel to the mid‐vein and after injection of ethylene maleic anhydride copolymer (EMA), followed by that induced in distal half leaves after inoculating the basal halves with TMV. Resistance in upper leaves following inoculation of the lower leaves with TMV was relatively low, while induction due to lesions caused by ethrel gave an intermediate degree of resistance. Estimation of resistance by size and number of local lesions was correlated with the amount of extractable virus as measured by enzyme‐linked immunosorbent assay (ELISA), thus indicating that in the resistant tissue virus replication, and not only the development of necrotic local lesions, is suppressed.An increase in a specific ribosomal fraction (R2), recovered by a two‐step procedure, was observed in tissues where resistance was most intense, i.e., between TMV stripes and after EMA injection. It may be that this specific ribosomal fraction participates in maintaining the resistant state.