bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro responses of different Armillaria taxa to gallic acid, tannic acid and ethanol
Authors: SHAW CHARLES G. 
Published: April 2007

Twenty‐one isolates from four Northern Hemisphere species of Armillaria (A. mellea, A. ostoyae, A. bulbosa. and the unnamed North American Group V) and two Southern Hemisphere species (A. luteobubalina and A. novae‐zelandiae) were grown on media with or without ethanol. gallic acid, or tannic acid. Ethanol increased dry weights for all isolates except one of A. bulbosa and colony diameters for all isolates of the Northern Hemisphere species except one of North American Group V. Ethanol decreased colony diameters for some isolates of the Southern Hemisphere species. Rhizomorph production increased for most isolates of Northern Hemisphere species on medium amended with tannic acid rather than gallic acid and on ethanol‐amended medium with or without gallic acid. Both Southern Hemisphere species formed rhizomorphs in abundance, regardless of the medium. For most isolates colony diameters and dry weights were reduced by gallic acid, with or without ethanol. but were increased by tannic acid, with or without ethanol.Acid and ethanol effects on colony weights and diameters were not consistent, however, and variation among isolates within each species was great enough for these media to be of little value in distinguishing among the species. Newly defined species of Armillaria have thus retained the attribute of extensive variation in cultural characteristics that is a feature of A. mellea, sensu lato, which necessitates evaluating the responses of several isolates before determining effects of any compound on growth of any species.
Evaluation of soil solarization for control of root diseases of row crops in Victoria
Authors: FORTER I. J. , MERRIMAN P. R. 
Published: April 2007

The effect of soil solarization on the viability of plant pathogens and disease was evaluated in Victoria. The treatment was tested in NW and S Victoria with natural soil inoculated with high inoculum levels of Eusarium oxysporum, Plasmodiophora brassicae, Sclerotium cepivorum, Sclerotinia minor, Sclerotinia sclerotiorum, Verticillium dahliae and the nematodes Meloidogyne javanica and Pratylenchus penetrans. Other experiments were established at sites with a previous history of disease.Solarization of artificially inoculated soils reduced inoculum levels to at least a depth of 10 cm and effectively controlled diseases caused by P. brassicae on broccoli, and S. minor and S. sclerotiorum on lettuce. The treatment reduced inoculum levels but not disease of carnations and watermelons affected by E. oxysporum, tomatoes affected by M. javanica, celery affected by P. penetrans, and onions affected by S. cepivorum. Results were inconclusive for tomatoes affected by V. dahliae.Experiments in naturally infested soils established that solarization reduced disease and increased yields of Chinese cabbage affected by P. brassicae, celery affected by P. penetrans, lettuce affected by S. minor and watermelon affected by root rot.Solarization reduced disease of onions affected by S. cepivorum but did not significantly increase yield. At all sites the treatment reduced the number of viable propagules of the pathogens to at least a depth of 10 cm.
The effect of powdery mildew (Erysiphe graminis f. sp. hordei) and leaf rust (Puccinia hordei) on spring barley in New Zealand. II. Apical development and yield potential
Authors: LIM L. G. , GAUNT R. E. 
Published: April 2007

Reduced yields caused by powdery mildew and leaf rust in two seasons were associated with reduced plant growth. Combinations of early, late and full epidemics in one season, and 12 epidemic combinations in the second, were designed to identify crop sensitivity to disease by comparing growth and development with healthy plants. Early epidemics reduced ear number by increasing tiller death, and reduced grain number by effects on spikelet, floret or grain abortion, depending on the type of epidemic. Epidemics later in crop growth increased floret and grain abortion and also reduced grain weight.There was no compensation by later‐determined components for reduced growth and delayed development at earlier growth stages. Plants infected at early growth stages were more sensitive to late infections, seen as effects on the later‐determined components, than plants which were healthy initially. Interactions occurred between epidemics at different times and are likely to occur between diseases and other constraints.
Influence of rootstock on the susceptibility of sweet cherry scions to bacterial canker, caused by Pseudomonas syringae pvs morsprunorum and syringae
Authors: GARRETT CONSTANCE M. E. 
Published: April 2007

In a field trial to determine whether the rootstock influenced the susceptibility of cherry cultivars to bacterial canker three cultivars (Napoleon, Roundel and JI 14039), each grafted on two rootstocks (F 12/1 and Colt), were subjected to natural infectionand to inoculation with three bacterial canker pathogens (Pseudomonas syringae pv. morsprunorum races 1 and 2 and P. syringae pv. syringae). Inoculations were made through leaf scars and through wounds. The high susceptibility of Napoleon and high resistance of JI 14039 were confirmed. Napoleon was more susceptible to inoculation through branches when on F12/1 than when on Colt but the reverse was true for leaf scar inoculations. JI14039 was more susceptible to race 1 inoculated through leaf scars when grown on F12/1 than when on Colt. No rootstock/scion interaction was detected with Roundel.The complexity of the relationships between the pseudomonad pathogens and their cherry hosts is briefly discussed.
Effects of fungicides on Drechslera spp. and leaf surface filamentous saprophytic fungi on Lolium perenne
Authors: THOMAS M. R. , SHATTOCK R. C. 
Published: April 2007

Small plots of Lolium perenne were treated between February and September 1979 with benomyl, triadimefon and chlorothalonil and the incidence and relative abundance of sporulating filamentous fungi measured on distinct lesions and senescent areas of leaves.Benomyl reduced the levels of most saprophytes but increased the levels of the two Drechslera species present. Triadimefon reduced levels of Drechslera species but allowed an increase in levels of Phoma and Epicoccum and in the number of naturally senescing leaves devoid of obvious filamentous fungal growth. In chlorothalonil‐treated plots, levels of all filamentous fungi except Epicoccum were reduced and, by controlling Drechslera species, the number of healthy leaves increased.
Multiplication and spread of pathovars of Xanthomonas campestris in host and non‐host plants
Authors: ROBINSON J. N. , CALLOW J. A. 
Published: April 2007

Multiplication and spread of respresentative strains of three pathovars of Xanthomonas campestris were monitored by maceration and plating from inoculated leaves of the host and non‐host plant species Oryza sativa, Poa trivialis, Brassica oleracea and Phleum pratense.Homologous interactions were characterized by higher multiplication rates and larger population increases than heterologous interactions, except for pv. oryzae which increased as much as pv. poae in leaves of Poa. Spread of heterologous pathovars was limited, but homologous pathovars were distributed throughout host leaves soon after inoculation. Pvs poae and oryzae (from Poaceae) demonstrated considerably greater population increases and higher initial multiplication rates than pv. campestris in leaves of all non‐host Poaceae. Pv. poae spread further into leaves of Oryza and pv. oryzae further into leaves of Poa and Phleum than did pv. campestris. Numbers of pv. poae declined in Brassica as did those of pv. oryzae, which was localized within 2 mm of the point of inoculation.
Effects of fungicides on long‐term cropping and fruit quality of apple
Authors: HUTCHEON J. A. , COYLE J. , HOLGATE M. E. , BYRDE R. J. W. 
Published: April 2007

The effects on cropping of 24 applications, over a 3‐year period, of each of five fungicidal programmes to control powdery mildew (Podosphaera leucotricha) were examined on the apple cultivar Cox's Orange Pippin. Trees receiving programmes based on ergosterol biosynthesis inhibitors (EBIs)‐fenarimol, a triadimefon/bitertanol mixture and an experimental compound coded PP 347‐each applied at 2‐week intervals during the growing season had significantly (c. 40%) less yield than those receiving the standard programme of binapacryl (not an EBI), applied weekly. Yield with a fourth EBI programme‐based on penconazole‐was also less than with binapacryl, but not significantly so. Both binapacryl and penconazole were used mixed with captan.The lower yields were due to fewer apples harvested rather than to lower individual fruit weight. Possible reasons underlying these effects are discussed: the anti‐gibberellin action of EBI compounds may be involved.
Virulence and aggressiveness of single‐zoospore isolates of Phytophthora fragariae
Authors: KENNEDY DIANA M. , DUNCAN JAMES M. , DUGARD PATRICIA I. , TOPHAM PAULINE H. 
Published: April 2007

A system for scoring the virulence of isolates of Phytophthora fragariae based on a scale of root rot from 0(no symptoms) to 5 (76‐100% roots roiled) on a series of strawberry cultivars is described. Thirty‐two single‐zoospore isolates from one field site were compared by subjecting their root rot scores to cluster analysis and this grouped them into two major clusters equivalent to physiologic races B66–3 and B66‐11, Different sub‐clusters of isolates of race B66‐11 produced different degrees of rotting on the same hosts. Apart from differences in virulence between the sub‐clusters there was some evidence for differences in aggressiveness between isolates within sub‐clusters.Increasing inoculum concentration by over 300‐fold increased rotting by c. 25% but did not alter the rankings of different isolate/host combinations. Repeated passage of isolates through cultivars of differing susceptibilities did not affect their pathogenicity.
Infection of resistant and susceptible cultivars of wheat by Pyrenophora tritici‐repentis
Authors: LOUGHMAN R , DEVERALL B. J. 
Published: April 2007

Conidial germination, appressorial formation. penetration of epidermal walls, formation of intracellular vesicles and growth of intracellular hyphae in epidermal cells occurred within 12 h of inoculation. Hyphae then grew slowly between mesophyll cells for the next 12 h. Some papillae formed beneath appressoria and most infected epidermal cells retained stain by 24 h after inoculation, indicating major changes in cellular physiology. Slight differences between cultivars in some of these events were not related to resistance.On the second day. intercellular hyphae emerged more extensively from the infection sites into the mesophyll of the susceptible cultivar Banks, and formed significantly larger mycelia than in the resistant cultivar BH1146 by 3‐5 days from inoculation. Rapid intercellular growth then continued in the susceptible cultivar but not in the resistant cultivar. Necrotic lesions expanded faster in the susceptible cultivar from day 3. By day 10. most lesions in this cultivar were large and light brown with a conspicuous chlorotic margin but those in the resistant cultivar were small and dark brown with inconspicuous chlorosis.
Patterns of development of Septoria nodorum and S. tritici in some winter wheat crops in Western Europe, 1981‐83
Authors: ROVLE D.J. , SHAW M W. , COOK R. J. 
Published: April 2007

In data collected at 19 sites in Western Europe during 1981‐83. two patterns of development of Septoria nodorum and S. tritici on foliage of winter wheal were distinguished. In sudden outbreaks, lesions appeared simultaneously on the upper leaf layers of crops, usually after the end of stem extension; these outbreaks were ascribed to short, heavy rain storms in which pycnidiospore inoculum in basal leaves was elevated up to 60 cm through the crop canopy. Gradual epidemics were characterized by disease arising on successive leaf layers as they appeared during sustained periods of weather suitable for inoculum transport and infection.The data indicate incubation periods of 2‐4 weeks for S. nodorum and 3‐5 weeks for S. tritici. it is suggested that a leaf layer cannot normally sustain more than one pathogen generation and that its infection arises from inoculum borne on leaves older than in the layer situated immediately below it. The potential level of disease in a crop may relate to the amount of inoculum present in spring. The proportions of disease caused by the two Septoria species varied greatly between sites and years, but the data provided no explanation.It is concluded that a septoria forecast scheme needs to recognise the importance of sudden disease outbreaks and to include not only weather but also host growth and inoculum factors.
Etiology of a newly described root rot of guar (Cyamopsis tetragonoloba) in Australia caused by Phytophthora cryptogea
Authors: STIRLING A. M. , IRWIN J. A. G. 
Published: April 2007

An isolate of Phytophthora obtained from diseased roots and stems of guar (Cyamopsis tetragonoloba) growing in waterlogged soil from Dalby. Queensland. was identified as Phytophothora cryptogea (P. drechsleri). Sex organs were not observed, Pathogenicity to guar seedlings was established under glasshouse conditions either by using a hypocotyl‐wound inoculation technique, or adding motile zoospores to seedlings growing under saturated conditions. This appears to be the first report of this disease. Seven isolates of P. drechsleri from hosts other than guar were shown to be pathogenic to guar following hypocotyls‐wound inoculation.The host range of the guar isolate was studied using both hypocotyl‐wound inoculation and zoospores. After hypocotyl inoculation, the following species were found to be susceptible: cantaloupe. cowpea, cucumber, mungbean, pea. pigeon‐pea, safflower. sunflower, tomato and watermelon. Slight symptoms were observed on bean and chickpea. When zoospores were used as the inoculum, only pea. pigeon‐pea, sunflower and safflower were highly susceptible. A range of guar cultivars and breeding lines were screened for resistance using zoospore inoculum, and although no genotypes were highly resistant, there were significant differences between disease reactions.
Effects of virus infection of faba bean on subsequent infection by Uromyces viciae‐fabae
Authors: OMAR S. A. M. , BAILISS K. W. , CHAPMAN G. P. , MANSFIELD J. W. 
Published: April 2007

Prior infection of faba bean with bean yellow mosaic virus (BYMV) and bean leaf roll virus decreased pustule density on leaves subsequently infected by Uromyces viciae‐fabae. Changes were most marked on young leaves showing conspicuous symptoms of systemic virus infection and in plants virus‐infected for at least 2‐4 weeks. Pustule density progressively decreased when inoculations were made with uredospore generations successively produced on and inoculated to BYMV‐infected leaves.Uredospore germination and germ tube length were similar on virus‐free and BYMV‐infected leaves and on agar seeded with spores produced for one or several generations on BYMV‐infected or virus‐free plants. Formation of appressoria was slightly reduced on BYMV‐infected leaves but changes in the post‐penetration development of the rust probably accounted for much of the decreased pustule production encountered.
Evaluation of selective media and bait methods for estimating Phytophthora cactorum in apple orchard soils
Authors: HARRIS D. C. , BIELENIN ANNA 
Published: April 2007

Soil plating, with a specially devised selective medium, gave estimates of Phytophthora cactorum in an East Mailing Research Station apple orchard soil up to three times those obtained by dilution and baiting with apple seedlings or cotyledons and using the most probable number analysis.When the same techniques were applied to a range of soils from apple orchards in south‐east England with a history of P. cactorum diseases the plating method failed in most instances, mainly because Pythium spp. rapidly swamped the plates. The dilution/baiting method was applicable to all soils though there was a tendency to underestimate because of anomalous results at lower soil dilutions.Oospores were the only propagules which could be confirmed as sources of P. cactorum colonies on soil isolation plates.
The establishment of systemic infection in leaves of oilseed rape by Leptosphaeria maculans
Authors: HAMMOND KIM E. , LEWIS B. G. 
Published: April 2007

In a series of growth room experiments in which leaves of Brassica napus var. oleifera were inoculated with ascospores or pycnidiospores of Leptosphaeria maculans successful infections progressed through three consecutive phases. Initial establishment in the mesophyll was succeeded by a phase of intercellular exploration, when hyphal proliferation was highly variable and host cell necrosis always ensued, and then by a systemic phase when hyphae were consistently sparse. Host cells associated with the hyphal front were capable of autofluorescence, accumulation of vital stains and plasmolysis, indicating that they were viable and that the pathogen was biotrophic throughout this sequence. During either of the first two phases permanent fungistatic containment, involving the formation of vesicles by disintegration of the hyphae, often occurred. Localization at the first phase was symptomless; at the second it was signified by a lesion with a clearly defined margin.There was a negative correlation between biotrophic potential and necrotrophic potential of three pathogenic isolates, on both the moderately susceptible cultivar Primor and the resistant cultivar Jet Neuf. As leaves aged, a progressively larger proportion of infections failed to become systemic. With increasing inoculum load, symptomless localization of infection diminished, the phase of necrosis extended, and the probability of irreversible systemic development increased.
Identities and pathogenicities of phytophthora spp. causing root rot of red raspberry
Authors: DUNCAN J. M , KENNEDY DIANA M. , SEEMULLER ERICH 
Published: April 2007

Phytophthora syringae, P. drechsleri, P. cactarutn, P. cambiuora and P. megasperma were isolated from the roots of red raspberry plants affected by severe root and crown rot with associated cane death. Phytophthora megasperma occurred most frequently and consisted of two types of isolates which differed in colony morphology, growth rates, and oogonial, oospore, sporangial and zoospore size, and pathogenicity to a range of plants. One type with large oospores was typical of P. megasperma var. megasperma, and was non‐pathogenic to red raspberries, while the other with smaller oospores and which grew more slowly in culture than the first, was highly pathogenic, producing symptoms similar to those observed in the field. Highly pathogenic isolates from Germany and the USA were of this type.All red and black raspberry cultivars tested were susceptible to the pathogenic type, although North American cultivars were generally less affected than British ones. Inoculated plants had reduced shoot and root weights, stem lesions and wilted and yellowed leaves. The blackberry × raspberry hybrid Tayberry and its blackberry parent were immune.Phytophthora drechsleri, P. cactorum and P. cambivora produced small to moderate amounts of root rot on red raspberry, and P. cambivora also caused slight symptoms on shoots.
Is celery yellow net c used by parsnip yellow fleck virus
Authors: SINGH H. , FROST R. R. 
Published: April 2007

Celery yellow net w s described by Hollings (1964) s severe dise se of celery (Apium graveolens L. var. duke (Miller) DC.) that could be transmitted by grafting nd occasionally by mechanical inocul tion with leaf extracts. Pemberton & Frost (1986) observed similar symptoms in celery crops. but were unable to isolate the causal agent.During recent attempts to isolate the causal gent of celery yellow‐spot, another disease previously reported by Hollings (1964) and Pemberton & Frost (1986), we found that two of our samples from crop in Cheshire contained different virus. As well as yellow spots, these two plants also had yellow‐net symptoms on the older leaves, and one of the plants was stunted with some distortion of the young leaflets. The two virus isolates appeared identical from extensive testing on range of herbaceous indicator plants, so one of them, CV506, w s selected for further study
Effect of crown rust on regrowth, competitive ability and nutritional quality of perennial and Italian ryegrasses
Authors: POTTER L. R. 
Published: April 2007

Infection of susceptible cultivars of perennial (Lolium perenne) and Italian (Lolium multiflorum) ryegrasses with crown rust (Puccinia coronata) reduced yield measured 6 weeks after infection and at two regrowth cuts. In perennial, but not Italian, ryegrass, rust infection of mixed swards of a resistant and a susceptible cultivar reduced the contribution to yield made by the susceptible cultivar and increased that of the resistant cultivar. This effect persisted for three regrowth cuts. The trend in effect on the number of tillers, but not plant height, was similar.Infection increased leaf protein in susceptible perennial ryegrass but had little effect in Italian ryegrass. In both species, rust reduced water‐soluble carbohydrate and the predicted digestibility of susceptible and resistant cultivars, but had no effect on quality of regrowth.
Susceptibility of winter and summer crops to root and crown infection by Bipolaris sorokiniana
Authors: WILDERMUTH G. B. , McNAMARA R. B. 
Published: April 2007

The susceptibility of 24 winter and 17 summer crops to infection by Bipolaris sorokiniana was tested in a glasshouse experiment by growing them in soil amended with wheat‐barley grain colonized by B. sorokiniana (0.2 g per 100 g soil). At anthesis, infection of both lesioned and randomly selected segments of roots and of crowns was determined by plating them on modified Czapek‐Dox Agar. Incidence of infection in winter crops was higher than in summer crops. Guar, mung bean, soybean and sunflower were the least infected of the summer crops while chickpeas and safflower were the least infected of the winter crops. Amongst the taxonomic groups tested, the highest incidence of infection occurred in the gramineous species and the lowest in the leguminous species.Five summer crops growing in the field were sampled and infection by B. sorokiniana confirmed. Cultivars of wheat, barley, triticale and oats were also screened in a field experiment. Amongst these winter cereals, oats was the least susceptible in both field and glasshouse experiments. Differences between cultivars in susceptibility to common root rot, measured by the degree of lesion development in the subcrown internode, were identified in wheat, triticale and oats but not in barley.