bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Quantitative Description of The Colonization of Susceptible and Resistant Radish Plants by Plasmodiophora brassicae
Authors: Kroll T. K. , Lacy G. H. , Moore L. D. 
Published: May 2008

AbstractThe degree and rate of primary and secondary cycle development by Plasmodiophora brassicae in the root hairs and root medullary rays, respectively, of a completely resistant, a partially resistant and a susceptible radish (Raphanus sativus) cultivar were compared. Seeds were germinated in an infested soil mixture and seedlings were harvested 2, 4, 6 and 8 days after sowing seed for observations of the primary cycle and 6, 12, 18, 24, 30 and 36 days after sowing seed for observations of the secondary cycle. No differences in the degree or rate of primary phase colonization were detected among the three cultivars. Initially, uni and/or bi‐nucleate secondary plasmodial stages were found in the cortex of all three cultivars. The number of these plasmodia was greatest in resistant and least in susceptible cultivars. No further colonization or symptom expression occurred in the completely resistant cultivar. In the partially resistant cultivar the appearance of advanced stage‐s of the fungus secondary cycle development were delayed until day 30 as compared with colonization of the susceptible cultivar in which advanced stages appeared by day 18. It is concluded that resistance is expressed during the initial stages of secondary cycle colonization.
Has the Plant a Resistance System Based on Interferon‐like Proteins? (Impressions from a meeting)
Authors: Kassanis B. 
Published: May 2008

AbstractThe short communication contains observvations on the workshop on pathognesis‐related proteins in plants held at the Research Institute of Plant Protection, Wageningen. The main criticism is that the scientists working on the problem or natural resitance present in plants, neglected the practical side of the investigation which is to find a suitable chemical treatment which would induce resistance to infection without being phytotoxic
Natural Infection of Tomato and Pelargonium in Germany by a Tombusvirus Originally Described from Pepper in Morocco
Authors: Vetten H. J. , Koenig R. 
Published: May 2008

AbstractTwo serologically apparently identical tombusviruses were isolated from glasshousegrown tomato plants showing mottle and malformation of the upper leaves and stunting of the shoot tips and, at a low rate, from a pelargonium plant, respectively. Both plant species were received from growers in southern Germany. In agar gel double diffusion tests and immuno‐electrophoresis, the two virus isolates could not be distinguished from a tombusvirus (MPV) isolated from pepper in Morocco by Fischer and Lockhart (1977), although there were some minor differences in the reported host responses. In the tomato planting, strong symptoms were produced only temporarily. The majority of the 104 tomato plants of 15 different cultivars which had become infected by MPV following mechanical inoculation of the leaves showed only mild symptoms in contrast to a similar group of plants which developed severe stunting and foliar deformation when infected with the type strain of tomato bushy stunt virus. MPV was translocated only occasionally to the upper parts of tomato seedlings which had been grown in virus‐containing soil, although root infections were more frequent. MPV is apparently not a major threat to tomato cultivation in Germany.
Cytological Evidence of the Association of a Geminivirus with the Tomato Yellow Leaf Curl Disease in Tunisia
Authors: Cherif C. , Russo M. 
Published: May 2008

AbstractSamples of tomato plants from Tunisia naturally or artificially infected with the yellow leaf curl disease were examined in thin sections with the electron microscope. Cytological changes were compared with those previously observed in similarly affected tomato plants from Israel. Evidence was obtained that also in Tunisia a non‐mechanically transmissible geminivirus is associated with the disease.
Detection of Avocado Sunblotch Viroid in Flower Buds by Polyacrylamide Gel Electrophoresis
Authors: da Grça J. V. , Mason T. E. 
Published: May 2008

AbstractA Rapid PAGE index method for avocado sunblotch disease for field trees which takes only 6 h, compared with 2—5 days for other previously described tediniques, has been developed and tested. Flower bud? are used instead of leaves as source material. All 52 flower Duu Siimplcs irom known bunblotcn‐infcctcd trees tested positive whilst only 37 out of 72 in‐fccted leaf samples gave positive results.
Activation of Teliospore Germination in Uromyces appendiculatus var. appendiculatus1)
Authors: Gold R. E. , Mendgen K. 
Published: May 2008

AbstractThe effects of light and host volatiles on teliospore germination in Uromyces appendiculatus var. appendiculatus were studied.1. Light intensities ranging 15–26 000 lux supported teliospore germination and basidiospore formation. The optimum light intensity was 17 000 lux under the described conditions. Light‐dark alternation was necessary for teliospore germination: no germination occurred under continuous light or continuous dark conditions. The process of teliospore germination, basidiospore formation, and basidiospore release followed a synchronous, rhythmic pattern of development. Teliospore germination was triggered by the phase change lights → dark (i.e. “light off”). Under long‐day conditions basidiospore release exhibited a nocturnal periodicity with peak maxima occurring ∼7 h after light was turned off.2. Fifteen days after a 10 d exposure to host volatiles, 70–80 % of the treated spores germinated; minor increases in spore mortality were observed. Inoculations made with seedling‐treated teliospores resulted in heavy pycnial infections.3. The heat and seedling activation methods developed for teliospores of bean rust proved ineffective when applied to dormant teliospores from six other unrelated rust species.
Comparative Studies on Some Isolates of Rhizoctonia solani in Egypt
Authors: Wasfy E. H. , Sheir H. M. , Darweesh M. M. 
Published: May 2008

AbstractNine isolates of Rhizoctonia solani from various hosts were selected for this study. The isolates were tested for their compatibility by an anastomosis test. Isolates were classified into two Egyptian anastomosis groups (EAG‐1 and EAG‐2). The isolates varied in virulence, thiamine requirement and quality and quantity of free and protein amino acids.
Release of Antifungal Phenolic Compounds from Cucumber Mosaic Virus‐Infected and Noninfected Cowpea Protoplasts
Authors: Ando Y. , Ehara Y. , Yamanaka S. 
Published: May 2008

AbstractFungitoxic phenolic compounds were released from cucumber mosaic virus (CMV)‐infected and noninfected cowpea protoplasts. These compounds were presumed by thin layer chromatography as similar compounds released into the leaf ambient fluids when CMV‐infected cowpea leaves were incubated in water. Larger amounts of the compounds were released from CMV‐infected cowpea protoplasts than from noninfected protoplasts.
Modulation de la Réponse du Xyléme selon la Nature de l'Agression Vasculaire
Authors: Moreau Mireille , Catesson Anne‐Marie 
Published: May 2008

RésuméL'évolution des cellules contiguës aux vaisseaux dans le xylème caulinaire de l'œillet est comparée après simple entaille (s. e.), introduction de spores deV. dahliae(iV. d.) ou deP. cinerescens(iP. c.). Tous les traumatismes expérimentaux entraînent des modifications ultrastructurales aboutissant à l'apparition de nouveaux types cellulaires. Parallèlement, les polyphénols vacuolaires sont metabolises et des vésicules “à cœur dense” apparaissent. Il s'agit là de phénomènes précoces et indépendants. Dans tous les cas, l'œillet réagit plus vigoureusement chez les iV. d.que chez les iP. c.L'étude de la gommose vasculaire révèle des differences quels que soient les critères retènus: vitesse d'installation, importance relative du phénomène, niveau de complexité structurale, chronologie d'apparition des différents constituants. Les relations éventuelles entre les structures cellulaires et les secretions gommeuses sont recherchées en comparant entre elles les situations de defense efficace (iV. d.) ou défaillante (iP. c.). Tous les elements d'analyse retenus dans ce mémoire confirment que, face a son parasite spécifique, la réponse de l'hôte est perturbée. On observe des blocages, des freinages, des déviations des voies de biosynthèse normalement mises en place par la plante en réponse à une agression fongique. Les differences de comportement de l'œillet vis‐a‐vis duVerticilliumet duPhialophoraprésentent une image de la spécificité parasitaire qui s'adapte bien au modèle récemment propose pardeWit(1981) pour le couple tomate/Cladosporium fulvum.
Effect of Azotobacter Exudates on Certain Micro‐Fungi Associated with the Phylloplane of Soybean
Authors: Singh R. P. , Singh Lokendra , Verma V. S. 
Published: May 2008

AbstractThe effect of different concentrations of Azotobacter chroococcum exudates on microfungi isolated from Soybean phylloplane was studied in vitro and in vivo. It has been found that the growth of some fungi was stimulated or suppressed whereas others showed fluctuations or remained unaffected depending upon the age of the plant, growth stage of the leaf, concentration of the exudates, method used to harvest fungi, and environmental conditions. Nutrient competition or production of biologically active substances like GA may be responsible for retarding the growth of fungi.
A Survey of German Hops for the Presence of American Hop Latent Virus (AHLV)
Authors: Eppler A. , Sander Evamarie 
Published: May 2008

AbstractThe presence of rod‐shaped viruses in German hops has been known for a long time and Hop Mosaic Virus (HMV) and Hop Latent Virus (HLV) were proved to be present by serological techniques. When another CARLA‐Virus, the American Hop Latent Virus was detected in England an extensive survey was carried out in the German hop growing regions and among wild hops. No natural occurrence of the virus could be detected. Only recently introduced plants of the American clone USDA 21055 in an isolated breeding garden were infected. Spread of the virus to German seedlings could not be detected.
The Influence of Ustilago maydis Upon Free Radicals Concentration in the Reproduction Organs of Maize
Authors: Michalov J. , Komaaar J. 
Published: May 2008

AbstractThe reproduction organs of maize are those most often attacked by Ustilago maydis. In the male organs it produces a decline in free radicals concentration and, conversely, a rise of concentration in the female organs (in ears). The smut proper, grown on the flower, exhibits an essentially higher free radicals concentration than the smut grown out on the ear of that plant. A smut mixture from flower and ear has only a slightly higher free radicals concentration than the separate ear smut, but an essentially lower one than the smut of the flower.
Ribulose Bisphosphate Carboxylase Protein and Enzymes of CO2 Assimilation in Barley Infected by Powdery Mildew (Erysiphe graminis hordei)
Authors: Walters D. R. , Ayres P. G. 
Published: May 2008

AbstractEffects were examined of barley powdery mildew (Erysiphe graminis f. sp. hordei) on the major leaf protein, ribulose‐l,5‐bisphosphate carboxylase (RuBPCase), and other enzymes of CO2 assimilation, phosphoenolpyruvate carboxylase (PEPcase) and malic enzymes, and enzymes associated with RuBPCase in the reductive pentose phosphate pathway. Activity of RuBPCase per unit fresh weight of leaf was inhibited by infection from the first sample, 3 days after inoculation, to the last sample, 24 days after inoculation, when healthy control leaves were visibly senescing. The inhibition occurred because the amount of RuBPCase protein (measured specifically by an immunological technique) was reduced from 6 days after inoculation and because activity per unit protein declined from 3 days until 21 days after inoculation, at which time there was little protein remaining. Activity of PEPcase per unit fresh weight of leaf was initially stimulated by infection but, thereafter, it was inhibited. Inhibition, like that also affecting malic enzymes (NAD) and (NADP), 3‐phosphoglycerate kinase, and glyceraldehyde‐3‐phosphate dehydrogenases (NAD) and (NADP), was associated with a decline in amounts of total soluble minus RuBP Case protein per unit fresh weight of leaf.Reduced amounts of leaf protein may be associated with reduced nitrate uptake by roots and fungal demand for nitrogen in mildewed plants.
Scanning Electron Microscopy of Xanthomonas campestris pv. pruni in Plum Petioles and Buds
Authors: du Plessis H. J. 
Published: May 2008

AbstractThe possibility that Xanthomonas campestris pv. pruni (Xcp) invades Golden King plum twigs systemically through petioles of infected leaves was investigated by scanning electron microscopy. Masses of Xcp cells were detected in longitudinal sections of helical xylem vessels of vascular bundles in petioles of naturally infected and inoculated leaves. Xcp colonies were also found in cortex tissue of small shields of twigs, adjacent to petioles of infected leaves. Single bacterial cells were detected in meristematic bud tissues of naturally infected samples only. The main route of ingress of Xcp into plum twigs appears to be systemically through petioles of infected leaves.The author thanks the staff of the SEM Unit of the FFTRI for assistance on scanning electron microscopy and Prof. M. J. Hattingh for critically reading the manuscript.
Antholysis in Cassava (Manihot esculenta Crantz) Possibly Caused by Mycoplasma‐Like Organisms
Authors: Jayasinghe U. , Pineda B. , Lozano J. C. 
Published: May 2008

AbstractPhyllody and apostasis of cassava plants were frequently observed during recent disease surveys in the Cauca Valley of Colombia. Many valuable cassava clones have been affected rendering them unsuitable for hybridization. Light and electron microscopic observations have revealed the presence of mycoplasma‐like organisms in the diseased phloem tissues. The causal agent is sensitive to tetracycline and streptomycin at 1000 ppm a. i., but not to penicillin.
Conidium Ontogeny in Pyricularia1
Authors: Rao K. Manibhushan , Jesudhas M. Louis 
Published: May 2008

AbstractConidium ontogeny of twenty‐three isolates of Pyricularia (including international races, some nutritional, coloured mutants and isolates obtained from cultivated and wild species of Gramineae) was studied. Among them, sixteen isolates were found to be of typical blastic type of conidiogenesis characteristic of the genus Pyricularia. Three coloured mutants and an international race showed gangliar type of conidiogenesis. However, two races and one nutritional mutant showed both the types.Most of the isolates tested are morphologically indistinguishable and potentially pathogenic with the respective hosts and on differential cultivars. Possible alteration of morphogenetic pattern of conidiogenesis by mutation and temperature response is suggested.
Evidence that the Low Molecular Weight RNA Associated with Chicory Yellow Mottle Virus is a Satellite
Authors: Piazzolla P. , Rubino L. 
Published: May 2008

AbstractChicory yellow mottle virus, ringspot strain (CYMV‐RS), supports the replication of a low molecular weight RNA (0.17 × 106 daltons) associated with CYMV‐T (type stain).Competition hybridization experiments revealed lack or nucleotide sequence homology between 0.17 × 106 mol. wt. RNA (Sat RNA) and CYMV‐RS genomic RNAs, and partial homology (33 %) with CYMV‐T genomic RNAs. However, such apparent partial homology can be due to contamination of CYMV‐T genomic RNAs with a multimeric form of Sat RNA having a similar molecular weight. On this account the hypothesis that CYMV‐T Sat RNA is a true satellite RNA becomes tenable.
A Technique for Continuous Observation of the Infection Process in Cucumber Anthracnose
Authors: Stumm D. , Gessler C. 
Published: May 2008

AbstractA new light microscope preparation technique for high magnification observation of living plant tissue and fungal penetration is described. Agar immersion is used in differential interference contrast microscopy (DIC) instead of coverslips (lens 40) or instead of coverslips and oil (lens 100).This technique is suitable for(a) longtime observation of living tissue, because the tissue to be observed remains on the plant, and for(b) thick and uneven samples, as no coverslips are required.With this technique it was possible to observe the dynamics of penetration of Colletotrichum lagenarium into epideral cells of cucumber cotyledons for 72 hours.A time lapse film using this technique is in preparation.
Response of Cucumber Cultivars and Other Cucurbitaceous Species to Infection by Hop Stunt Viroid1
Authors: Yaguchi S. , Takahashi T. 
Published: May 2008

AbstractThe response of 8 different species within the Cucurbitaceae to hop stunt viroid (HSV) was examined. Some of these plants developed several kinds of systemic symptoms depending upon species, variety or cultivar infected. Among 12 out of 26 cucumber cultivars become infected severely, so visual symptoms are reliable for diagnosis because symptom severity is correlated with viroid content. Other cucurbitaceous species except Citrullus lanatus, Cucurbita maxima and Cucurbita moschata were also susceptible. Among them, Benincasa hispida was found to be a more suitable bioassay plant than Suuyou cucumber which has been hitherto used.
Survival of Hop Stunt Viroid in the Hop Garden1)
Authors: Yaguchi S. , Takahashi T. 
Published: May 2008

AbstractA lot of 105 specimens from 25 families including weeds or wild plants which had grown naturally in the severely infested hop garden were tested for detecting reservoir plants for hop stunt viroid (HSV). HSV was detected in hop plants only. Susceptibility tests with various cultivated plants including 14 families indicated that hop and Humulus japonicus developed visible symptoms, while tomato was symptomless. When infected hop plant residues, leaves and cones, were left to be weather‐beaten, infectivity of HSV was completely lost within 3 months. No transmission through the pollen or the ovule was demonstrated. HSV could survice in root systems of hop plants during the winter months. Based on these results, the route of HSV survival in the hop garden was discussed.
Blue‐Stain Fungi on Nothofagus from Chile—Including Two New Species of Ceratocystis Ellis & Halst.
Authors: Butin H. , Aquilar Angelica M. 
Published: May 2008

AbstractA description is given of four species of the ascomycetous genus Ceratocystis isolated from different species of the tree‐genus Nothofagus in Chile. Two of these are described as new species based on the characteristics of their ascospores, ascocarps and conidial states in culture. Ceratocystis piceae (Münch) Bakshi and C. pilifera (Fries) C. Moreau were responsible for important blue‐stain in timber of Nothofagus pumilio (Poepp. et Endl.) Krasser; Ceratocystis nothofagi Butin sp. nov. and C. valdiviana Butin sp. nov. were found in native stands of different species of Nothofagus causing less intensive discoloration in bark and wood of dead trees.
Effect of Chitosan, Chitin and some Aminosugars on Growth of Various Soilborne Phytopathogenic Fungi
Authors: Stössel P. , Leuba J. L. 
Published: May 2008

AbstractThe effect of bleached chitin, 66% and 91% deacetylated chitosan, respectively, as well as some aminosugars on in vitro radial growth of several phytopathogenic oomycetes and deuteromycets was studied In contrast to chitin, chitosan was inhibitory to the fungi The antifungal activity depended on the degree of deacetylation, the particle diameter of the polymer, the growth medium and the pH. Likewise, deacetylation of the monomers different media varied, indicating a possible counteraction by the carbohydrate sources.
Studies in Heterobasidiomycetes, Part 38*)Sphacelotheca polygoni‐persicariae G. Demi & Oberw. spec. nov.
Authors: Deml G. , Oberwinkler F. , Bauer R. 
Published: May 2008

AbstractA new species, Sphacelotheca polygoni‐persicariae, parasitizing the ovaries of Polygonum persicaria L. is described. This smut, collected several times in Madeira, Portugal, differs from other species of that genus, by its host plant and the reticulated teliospore ornamentation.On the basis of the morphological and ultrastructural characters of S. polygoni‐persicariae, in connection with some recently published data on siderophore formation and 5S ribosomal RNA sequences it can be assumed that 1) members of the genus Sphacelotheca are separated from typical Ustilago species of Poaceae, 2) Sphacelotheca is restricted to species parasitizing Polygonaceae, and 3) species of Sphacelotheca and Microhotryum as well as those Ustilago species which parasitize in the flowers of Polygonaceae are closely related.
Einsatz von V. lecanii als biologisches Schädlingsbekämpfungsmittel gegen den Bohnenrostpilz U. appendiculatus var. appendiculatus im Feld und im Gewächshaus
Authors: Grabski G. C. , Mendgen K. 
Published: May 2008

Abstract The use of Verticillium lecanii as a biological control agent against the bean rust fungus Uromyces appendiculatus var. appendiculatus in the field and in the glasshouse The deuteromycete V. lecanii parasites uredo‐ and teliospores of the bean‐rust‐fungus U. appendiculatus var. appendiculatus. We investigated the conditions for the use of the hyperparasite as biological control agent in the field and in glasshouses.The growth rate of the hyperparasite was 0,3 cm per day at 25 °C. Under suitable conditions in the lab (25 °C, 100 % r. h.) it took about 20 days to invade 100 % of uredospores and 65 % of teliospores.We failed to prevent the spread of bean‐rust‐fungus spores in the field, but we succeeded in the glasshouse by 68 %, compared to the untreated controls, using the hyperparasite V. lecanii as biological control agent.
Sugar‐specific Attachment of Pseudomonas syringae pv. glycinea to Isolated Single Leaf Cells of Resistant Soybean Cultivars
Authors: ÉRsek T. , Gáborjáanyi R. , Höltzl P. , Király Z. 
Published: May 2008

AbstractPhase‐contrast and scanning electron microscopy showed races of P. synngae pv. glycinea uniformly distributed over and attached to the whole surface of isolated single leaf cells of resistant soybean cultivars, as early as 30 to 180 min after inoculation. On the contrary, attachment in the compatible interaction did not occur within 10—15 h. In a later period, compatibility was characterized by the formation of adherent bacterial clusters.Early attachment of races 1 and 6 to cv. Harosoy and that of race 5 to cv. Flambeau leaf cells, each representing incompatible interaction, could be inhibited by L‐rhamnose and D‐glucose, respectively. Furthermore, the lack of Mn2+ and Fe2+ and heat‐treatment of plant cells also affected the early attachment in incompatible combinations and resulted in cluster formation, suggesting incompatibility rather than compatibility to be the active phenomenon.Pre‐inoculation of cells with an incompatible race induced changes that caused compatible bacteria also to distributively attach to plant cell surface indicating that a transfer of information or surface alterations occur upon attachment in incompatible interaction.
Biological Control of Fusarium‐wilt in Carnation With Serratia liquefaciens and Hafnia alvei Isolated from Rhizosphere of Carnation
Authors: Sneh Baruch , Agami Orna , Baker Ralph 
Published: May 2008

Abstract Serratia liquefaciens provided better protection of carnations from infection by Fusarium oxysporum f. sp. dianthi, than did Hafnia alvei. The protection occurred when the bacterial isolates were applied to the cuttings before rooting, but not when applied to the root system of rooted cuttings. S. liquefaciens was recovered from carnation stem segments along the stem up to the top after 60 days but after 120 days they were recovered only up to 2.5cm. Zones of inhibition of Fusarium‐conidia sprayed on agar plates previously incubated with stem segments appeared around the bacterial colonies of S. liquifaciens after additional incubation for 24—48h.