bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential Responses of Host and Non‐host Substrata on Germination of Ascospores of Sclerotinia sclerotiorum
Authors: Singh U. P. , Singh R. B. 
Published: May 2008

AbstractEffect of host.(Cicer arietinum L.) and some non‐host (Allium cepa L., A. Sativum L., Ocimum sanictum L., Azadirachta indica Juss., Zingiber officinale Roscoe. And Curcuma longa L.) substrata on the germination of ascospores io Sclerotinia sclerotiorum (Lib.) de Bary has been observed. Maximum germination was noticed on flower petals of gram (C.arietinum) with minimum time (2.5 h) for germ tube initiation. Among the non‐host substrate germination was completely inhibited on ginger rhizome peeling whereas delayed germination (after 12h) and lowest germination percentage (48%) as compared with other non‐hosts, were observed on turmeric rhizome peeling. It is suggested that ginger extract may be effective in controlling stem rot and wilt of gram incited by S. sclerotiorum in the field.
Inhibition of the Hypersensitive Reaction in Tobacco Leaves by Extracellular Polysaccharides from Phytopathogenic Pseudomonads*)
Authors: Mazzucchi U. , El‐Banoby F. E. , Rudolph K. 
Published: May 2008

AbstractLipopolysaccharides (pr‐LPS) and extracellular polysaccharides (EPS) were prepated from in vitro‐cultures of phytopathogenic pseudomonads (Pseudomonas phaseolicola race 1 and race 2, P. aptata, P. tabaci) and purified. The preparations were dissolved in water (0.25–2.5 mg/ml) in infiltrated with P. aptata or P. pisi (9 × 107 cells/ml). Whereas the hypersensitive rzaction against P. aptata and P. pisi was inhibited by C.25 mg/ml of pr‐LPS in most of tae cases, the same concentration of EPS caused only partial or no inhibition. However, at 2.5 mg/ml most of the EPS‐preparations caused a complete inhibition. The LPS and EPS‐preparations of P. phaseolicola race 1 caused less inhibition than those of race 2.
Production and Pathogenicity to Wheat of Pseudocercosporella herpotrichoides Conidia
Authors: Higgins S. , Fitt B. D. L. 
Published: May 2008

AbstractWeekly estimates of numbers of Pseudocercosporella herpotrichoides conidia on naturally infected wheat straw, made from February to July 1982, showed there were most conidia (8.1 × 106 per straw) in February and least (1.9 × 104 per straw) at the end of June. The viability of these spores remained high throughout this period, with an average of 85 % germination after 24 h.After removal of spores produced in the field, straws were incubated at 5, 10, 15, 20 or 25°C and subsequent sporulation assessed after 3 or 5 weeks. The optimum temperature for spore production was 5°C and very few spores were produced at 25°C. There was no difference in viability between spores produced at different temperatures.Wheat seedlings placed amongst infected straw collected and retained spores on the upper and lower surfaces of all leaf blades and on outer leaf sheaths. Both naturally dispersed spores and spores sprayed on to plants were not removed by subsequent rainfall.When wheat seedlings were inoculated between the coleoptile and outer leaf sheath with different numbers of P. herpotrichoides spores, lesion development was most rapid in seedlings inoculated with the greatest numbers of spores. However, after incubation for 12 weeks visible lesions were present on all plants inoculated with > c. 10 spores.
Beet Necrotic Yellow Vein Virus: Purification, preparation of Antisera and Detection by Means of ELISA, and Electro‐Blot Immunoassay
Authors: Koenig R. , Lesemann D.‐E. , Burgermetster W. 
Published: May 2008

AbstractThe best results in attempts to purify beet necrotic yellow vein virus were obtained with a slightly modified Triton × 100 method originally described by Hullet al. (1976) for cauliflower mosaic virus. Immunosorbent electronmicroscopy (ISEM), the double antibody sandwich form of enzyme‐linked immunosorbent assay (ELISA) and electro‐blot immunoassay (EBIA) yielded similar result when sugar beets were tested for the presence of virus. ISEM and EBIA ofer the advantage that in addition to serology a second parameter, i.e. either particle morphology or coat protein molecular weight, is used to identify the virus. Specific and possibly nonspecific reactions are thus more readily distinguished and antisera can be used which may still contain some antibodies to normal plant constituents. However, with these methods only a limited number of samples can be studied at a time, therefore ELISA is presently the method of choice for large scale routine testing.Zusammenfassung Beet necrotic yellow vein virus: Reindarstellung, Herstellung von Antiseren Und Nachweis Mit Hilfe von ELISA, Immunosorbent electronmicroscoy und Electro‐Blot Immunoassay Bei Versuchen Zur Reindarstellung des beet necrotic yellow vein virus wurden die besten Ergebnisse mit einer leicht modifiziertem Triton × 100 Methode erzielt, die ursprüng für das cauliflower mosaic virus von Hullet al. (1976) entwickelt worden war. Immunosorbent electronmicroscopy (ISEM), double antibody‐sandwid, ELISA und electro‐blot immunoassay (EBIA) ergaben ähnliche Resultate bei der Unteuchung von Zuckerrübenwurzelproben. ISEM und EBIA haben den Vorteil, daß neber der scrolognchen Reaktivität noch ein zweites Merkmal zum Nachweis des Virus eingeserz wird, bei ISEM die Partikelmorphologie und bei EBIA das Molekulargewicht des Hüllprodtim badurda kännen spezifische und eventuell unspezifische Reaktionen besser unterschreden werden und es können Antiseten verwendet werden, die noch Antikörper gegen normale Pflauzenbestandteile enthalten. Da mit diesen Methoden jedoch nur eine begrenzte Anzabl von Probcagleichzeitig untersucht werden kann, ist für Massenuntersuchungen ELISA die Methode der Wahl.
Studies on Mechanisms of Splash Dispersal of Spores, using Pseudocercosporella herpotrichoides Spores
Authors: Fitt B. D. L. , Lysandrou M. 
Published: May 2008

AbstractSimulated raindrops, 4 or 5 mm in diameter, fell 13 m onto target water films, with Pseudocercosporella herpotrichoides spores incorporated into either drops or targets. Resulting splash droplets were collected on fixed photographic film and numbers of droplets, spore‐carrying droplets and spores determined.The patterns of dispersal of splash droplets, spore‐carrying droplets and spores with distance and droplet size were similar for 4 mm and 5 mm incident drops with spores incorporated into either targets or drops. Numbers of droplets, spore‐carrying droplets and spores decreased with increasing distance from targets and none were collected at 1 m. However, more spores were dispersed by 5 mm than by 4 mm drops and with spores in targets than with spores in incident drops. Whereas most splash droplets were in the smallest size category (0–100 μm), most spore‐carrying droplets were 200–400 μm and most spores were in droplets with diameter greater than 1000 μm. Regressions of square root (number of spores) on droplet diameter were significant (p < 0.001) in all cases. The slopes of regression lines were greater when spores were in targets than when they were in incident drops. Splash droplets were collected up to a height of 70 cm, with most between 15 and 20 cm. The dye experiment showed that most splash droplets contained liquid from both incident drop and target film.
Corynebacterium fascians: Phytopathogenicity and Numerical Analysis of Phenotypic Features
Authors: Elia S. , Gosselé F. , Vantomme R. , Swings J. , Ley J. De 
Published: May 2008

AbstractForty‐four Corynebacterium fascians strains from different geographical origins and host plants were characterized by their phytopathological capacity towards different host plants together with 206 morphological, biochemical and physiological features.The numerical analysis of the phenotypic features utilizing the SSM similarity coefficient and the average unweighted pair‐group clustering method revealed that all Corynebacterium fascians strains form a rather homogeneous cluster: over 80%, SSM exists between the 44Corynebacterium fascians strains from phenon II. From the present results the reclassification of C. fascians as Rhodococcus rhodochrous is not obvious.
Lack of Involvement of Nutrients in the Latency of Colletotrichum gloeosporioides in Unripe Avocado Fruits
Authors: Prusky D. , Ascarelli A. , Jacoby B. 
Published: May 2008

AbstractHypobaric pressures prevented the ripening of avocado fruit discs and the development of Colletotrichum gloeosporioides infection on them. The same condition did not prevent the growth of C. gloeosporioides on potato dextrose agar. Using this system it was shown that the resistance of unripe avocado fruit discs does not originate in the lack of subsrate for fungal growth.
Infection and Stroma Formation byVenturia inaequalison Apple Leaves with Different Degrees of Susceptibility to Scab
Authors: Gessler C. , Stumm D. 
Published: May 2008

AbstractConidia ofVenturia inaequalisgerminated and formed appressoria on all leaves independently of age and origin within the first 15 hours after inoculation. On the youngest expanded leaves of the apple variety Golden Delicious 80% of the conidia developed stromata within the first 24 hours, sporulation occurred after 8 days. On the second leaf (counted from the top of the twig) stroma formation was slowed down compared to the first and sporulation occurred after 10 days only. On the third leaf the fungus rarely formed stromata and never sporulated. The fourth leaf already showed complete ontogenetic resistance. In the diploid variety Priscilla the gene Vf, which confers resistance against scab to apple leaves, was expressed as reduced stroma formation without sporulation, as in the case of ontogenetic resistance. In the triploid variety Sir Prize with the gene Vf, stroma formation was retarded and colonization and sporulation occurred later on the first leaf, similarly to the reaction of the second leaf of variety Golden Delicious.
High Levels of Resistance in Agropyron Species to Barley Yellow Dwarf and Wheat Streak Mosaic Viruses
Authors: Sharma H. C. , Gill B. S. , Uyemoto J. K. 
Published: May 2008

AbstractSeveral Agropyron species were tested for new sources of resistance to barley yellow dwarf virus (Bydv) and wheat streak mosaic virus (WSMV). With BYDV strain PAV, 11 of the 17 Agropyron species showed no virus transmission when plants were given access feed by viruliferous Rhopalosiphum padi. Similar trials with BYDV strain RMV (vectored by R. maidis) indicated that all plants, except susceptible control plants, remained virus free. Virus status was confirmed by enzyme‐linked immunosorbent assays. When plants were mechanically inoculated with WSMV, 11 Agropyron species failed to express symptoms, while five other species showed a segregating response or had some accessions segregating and some resistant. Test results suggest that resistance to BYDV and WSMV in Agropyron species does not appear to be correlated with any specific genome of Agropyron species although most of the Agropyron species containing S genome were resistant to BYDV and WSMV.
Corn Stunt Spiroplasma in Dicotyledonous Plants
Authors: Alivizatos A. S. 
Published: May 2008

AbstractCorn stunt spiroplasma (CSS) was transmitted by the leafhopper vector Euscelidius variegatus (Kirschbaum) and produced symptoms on four dicotyledonous plant species, Sinapis alba L. (mustard), Pisum sativitm L. (pea), Raphanus sativus L. (radish) and Spinacia oleracea L. (spinach). The vectors became infective by microinjection with a broth culture of CSS. This insect also acquired CSS from infected mustard plants and transmitted it to healthy ones.
Detection of Prune Dwarf Virus by ELISA in Meristem‐Propagated Sour Cherry Plants During in vitro Culture
Authors: Baumann Gisela , Casper R. , Kornkamhaeng Pajchima 
Published: May 2008

AbstractTissue‐cultured plantlets which were derived from meristems of a sour cherry plant infected by prune dwarf virus were examined by enzym‐linked immunosorbent assay (ELISA). The virus could be detected with sufficient reliability in 17‐week‐old rooted plant‐lets still growing in vitro.
Electro‐Blot Immunoassay—A Means for Studying Serological Relationships among Plant Viruses?
Authors: Burgermeister W. , Koenig R. 
Published: May 2008

AbstractThe coat proteins of tymo‐, tombus‐, como‐, nepo‐, tobamo‐, potex‐, carla‐ and potyviruses were subjected to sodium dodecylsulphate (SDS)‐polyacrylamide gel electrophoresis, electro‐blotted onto nitrocellular membranes and reacted with homologous and heterologous antìsera to intact plant viruses. Immune complexes were detected after reaction with alkaline phosphatase‐labelled goat anti‐rabbit antibodies. SDS coat proteins of comoviruses reacted only with antisera which were homologous for their intact particles. In all other groups, however, a rather broad range of serological relationships was detected. With a number of viruses, serological relations to other members of the same group were demonstrated for the first time. SDS coat proteins of maclura mosaic virus, a possible potyvirus, and of beet necrotic yellow vein virus, a possible tobamovirus, did not react with antisera to definitive members of the respective groups. Several unexpected reactivities of SDS coat proteins of viruses from one group with antisera to viruses in other groups were, however, also observed. This indicated that electro‐blot immunoassay, like other serological methods, cannot be used reliably to assign a virus to a certain group. The SDS coat proteins of several tombusviruses were able to mimic serological reactions by a direct binding of enzymelabelled antibodies which occurred also without serum treatment.
Search for Viroids and Other Small RNAs Associated with Forest Damage
Authors: Schumacher J. , Loss P. , Riesner D. 
Published: May 2008

AbstractWe examined whether viroids may be involved as the causative agents of forest damages which have been observed in Germany during the last decade. A crude RNA extract was prepared from healthy and diseased copper beech, spruce, and pine trees and was analysed by two‐dimensional gel electrophoresis which resolves RNA bands in the molecular weight range from 25,000 to 106. Viroids are known to consist of single stranded circular RNA and are clearly differentiable in the electrophoresis used here from cellular RNA. Viroids could not be found in any of the samples investigated. In all samples from diseased trees, however, other additional RNA bands were discovered which were more similar to cellular RNA than to viroids in their electrophoretic properties. It is uncertain whether these diseased‐associated RNAs are due to an infection or originate from a modified nucleic acid metabolism.
Barley Yellow Mosaic Virus: Purification, Electron Microscopy, Serology, and other Properties of two Types of the Virus
Authors: Huth W. , Lesemann D.‐E. , Paul H.‐L. 
Published: May 2008

AbstractFrom naturally infected barley plants two types of barley yellow mosaic viruses have been isolated in Federal Republic of Germany. Both are identical in morphology, showing a bimodal length distribution (270–289 nm and 568–600 nm), and in symptomatology. Both induce conspicuous cytoplasmic inclusions of the pinwheel type and laminated aggregates, as well as threedimensional crystal‐like arrays of membrane material. The types differ, however, in buoyant density, serology, and transmissibility. One is transmissible by soil as well as mechanically (BaYMV‐M), and does not react with a Japanese antiserum to the Japanese virus (BaYMV‐J). The other type (BaYMV‐NM) is only transmissible by soil and reacts with BaYMV‐J‐antiserum. From mechanically infected plants BaYMV‐M was purified, and an antiserum was produced, from soil‐infected plants only mixtured BaYMV‐NM and ‐M could be obtained. BaYMV‐NM prevailed during winter, but with rising temperatures in spring BaYMV‐M was predominant.BaYMV‐M and the ‐M‐NM mixture had each two species of nucleic acids (2.7–2.8 × 106 and 1.4–1.5 × 106 d) and two major protein subunit bands were found in SDS‐PAGE (35–36 × 103 and c. 29 × 103 d).
Activité Fongicide du N‐cetyl N,N,N‐triméthylammonium Contre Botrytis cinerea Pers.
Authors: Pezet R. , Pont V. 
Published: May 2008

Abstract Fungicidal activity of N‐cetyl N,N,N‐trimethyl ammonium chloride to Botrytis cinerea Pers. Grey mould of grapes caused by Botrytis cinerea is the most important phytopatho‐logical problem in swiss vineyards, since the appearance of resistant strains to dicarboxi‐mides. Research for new chemicals is necessary. One compound, a cationic surfactant, the N‐cetyl N,N,N‐trimethyl ammonium chloride (CTAC), is very active in vitro against Botrytis cinerea. This product disturbs lethally the plasma membrane of conidia.
Further Electron Microscopical Studies of Induced Resistance of Barley against Erysiphe graminis f. sp. hordei
Authors: Ebrahim‐Nesbat F. , Schönbeck F. 
Published: May 2008

AbstractBarley leaves were treated with a resistance inducer and inoculated with Erysiphe graminis two days later. 68 hours after inoculation many infection sites with cytoplasmic aggregations with increased number of golgi apparatus and increased endoplasmic reticulum could be observed. The extrahaustorial membrane invaginated and some free pieces of membrane appeared in the matrix. The haustoria vacuolized partially and curly filamentous electron dense material occurred. These changes took place after protective as well as after curative treatment. Due to cytochemical studies the vacuolar electron dense material in the vacuoles of the haustoria contained polymers of mannose or glucose.
Peroxidase and Polyphenol Oxidase Associated with, Induced Resistance of Mung Bean to Rhizoctonia solani Kuhn
Authors: Arora Y. K. , Bajaj K. L. 
Published: May 2008

AbstractPeroxidase and polyphenol oxidase activities and peroxidase isozyme patterns were determined at different stages of hypocotyls of mung bean infected with Rhizoctonia solani. The effect of ethephon (2‐chloroethyl phosphonic acid) has been studied. Peroxidase activity increased at 24 h after inoculation as compared with controls followed by a decline later. It increased at 120 h. Polyphenol oxidase activities increased after inoculation. Ethephon treatment increased the resistance to Rhizoctonia solani and enhanced peroxidase and polyphenol oxidase activities. Peroxidase isozyme pattern was found to change as a result of inoculation and ethephon treatment. The results indicated that ethephon‐induced resistance was related to peroxidase and polyphenol oxidase activities.
Effets de Traitements Fongicides aux Imides Cycliques sur les Populations de Sclerotinia minor dans le Sol
Authors: Davlt P. , Martin C. 
Published: May 2008

AbstractAbout the effects of cyclic imides fungicidal treatments on soil populations of Sclerotinia minorWhen S minor selerotia were incubated in natural soils, they were gradually attacked by a varied antagonistic flora. This phenomenon was seriously slackened when cyclic imides (iprodione of vinclozolin) at 25 or 50 mg.l‐1 were incorporated into the soil, in laboratory trials or in normal conditions of cultivation. These fungicides (which are currently used to control S. minor) seemed to protect selerotia by preventing the development of antagonistic fungi. Selerotial germination was inhibited by vinclozolin but, if the duration of contact was less than 5 weeks, the phenomenon was fully reversible, even in the presence of very high concentrations (500 mg.l‐1).When an inoculum of Trichoderma sp. was added to natural soils, selerotia were rapidly damaged. An even faster decrease of S. minor populations resulted from the incorporation of cyclic imides into these Trichoderma‐enriched soils. These organisms are not very susceptible to such fungicides. It is suggested that a joint utilization of these biological auxiliaries and of cyclic imides should be a way to avoid the appearance of a biological unbalance due to an exclusive use of fungicides.
Production of Pectic Enzymes by Fusarium oxysporum f. sp. cepae and its Involvement in Onion Bulb Rot
Authors: Holz G. , Knox‐Davies P. S. 
Published: May 2008

Abstract Fusarium oxysporum f. sp. cepae produced an exo‐polygalacturonase (exo‐PG) and endopectin‐trans‐eliminase (endo‐PTE) in a mineral medium supplemented with a restricted supply of either D‐galacturonic acid or onion cell walls. These enzymes were also extracted from infected onion tissue, but only endo‐PTE caused tissue maceration and cell death.The patterns of host tissue colonization and pectic enzyme production were followed during bulb rot development. Stem plates were invaded within two weeks of inoculation. The pathogen then remained confined to the stem plates for several weeks or months, before spreading to the outer fleshy scales to initiate a basal rot. In most cases the inner leaf sheaths containing the lateral bud remained healthy. Exo‐PG activity m stem plate tissue was greatest at two weeks after inoculation, then it declined. Endo‐PTE was not detected in newly invaded stem plate tissue, but was recovered from infected stem plates before decay and from the bases of bulb scales and leaf sheaths at the onset of bulb rot. There was no pectic enzyme activity in uninvaded onion tissue.Spread of the fungus and pectic enzyme production in two Caledon Globe genotypes susceptible or tolerant to F. oxysporum f. sp. cepae were similar, but the onset of bulb rot in tolerant genotypes was considerably delayed.
Pectic Enzyme Production by Fusarium oxysporum f. sp, ccpac: Induction by Cell Walls from Different Parts of Onion Bulbs at Different Growth Stages
Authors: Holz G. , Knox‐Davies P. S. 
Published: May 2008

Abstract Fusarium oxysporum f. sp. cepae produced significantly different amounts of pectic enzymes when grown on cell walls from morphologically different parts of onion bulbs. Cell walls from stem plate tissue of both tolerant and susceptible onion genotypes allowed a rapid and high production of both exo‐polygalacturonase and endo‐pectin‐frans‐eliminase. Bulb scale cell walls from susceptible genotypes induced synthesis of these enzymes at much lower rates and levels, whereas bulb scale cell walls from tolerant genotypes gave poor induction of pectic enzyme synthesis. Leaf sheath cell walls from both susceptible and tolerant genotypes were poor inducers of enzyme synthesis. Enzyme induction by cell walls from leaf sheaths and bulb scales of tolerant genotypes increased dramatically during ageing. Differences in pectic enzyme accumulation on cell walls were not related to fungal growth. These patterns of enzyme induction could help to explain susceptibility or tolerance of bulb scale and leaf sheath tissue of the different genotypes.
The Relationship Between Peroxidase Activity and the Resistance of Tomatoes (Lycopersicum esculentum) to Verticillium dahliae
Authors: Reuveni R. , Ferreira J. F. 
Published: May 2008

AbstractThe levels of peroxidase activity in roots of non‐infected tomato plants resistant to Verticillium dahliae Kleb., were found to be considerably higher than those in the roots of susceptible plants. Similar differences were found in the leaves but were not significant as in the roots. Peroxidase activity increased in leaves, stems and roots of both susceptible and resistant plants after infection with V. dahliae. The ratio of the increase in leaves and roots of susceptible plants was greater than those of resistant plants. A positive correlation was found between the peroxidase activity in the roots of eleven cultivars/breeding lines and presence of Ve gene.