bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterisation and pathogenicity of bacteria from shoot tips of the globe artichoke (Cynara scolymus L.)
Authors: PEŃALVER R , DURÁN‐VILA N , LÓPEZ M M 
Published: February 2008

SummaryBacteria have been isolated from shoot tips of symptomless globe artichoke plants. These were identified as Pseudomonas fluorescens, Pseudomonas marginalis, Pseudomonas spp., Serratia liquefaciens, Enterobacter agglomerans/Erwinia, Agrobacterium radiobacter, an unidentified member of Rhizobiaceae and another classified in the “corynebacteria” group. The most frequently isolated species was P. fluorescens, biovars II and III. The endogenous character of these bacteria was studied in plants growing in vitro and in the open field. P. fluorescens, P. marginalis, S. liquefaciens and E. agglomerans/Erwinia caused symptoms in plants growing in vitro, but only P. fluorescens biovar II and P. marginalis produced symptoms in plants growing in open fields. Differences in pathogenicity were observed on inoculated plants growing in vitro or in the open field. This suggests that several endophytic bacterial species may be responsible for the high levels of contaminants found during the micropropagation of globe artichoke.
Identification of a second distinct strain of beet mild yellowing luteovirus using monoclonal antibodies and transmission studies
Authors: STEVENS M , SMITH H G , HALLSWORTH P B 
Published: February 2008

SummaryThe variation among isolates of beet mild yellowing luteovirus (BMYV), collected from commercial crops of sugar beet during 1990, 1992 and 1993, was studied using monoclonal antibodies and transmissions to indicator species. The common strain of BMYV, which occurs throughout the sugar‐beet root growing area, reacts with monoclonal antibodies MAFF 24, BWYV‐BC‐510H and BYDV‐PAV‐IL‐1, and infects Capsella bursa‐pastoris. A second strain, which failed to react with monoclonal antibody BYDV‐PAV‐IL‐1 and which did not infect C. bursa‐pastoris, was identified in 11% of sampled infected plants. The implications of the properties of this strain for the epidemiology of BMYV are discussed.
The sealed storage of moist flax with and without the use of chemical preservatives
Authors: EASSON D L , ANDERSON R , SHARMA H S SHEKHAR 
Published: February 2008

SummaryThe suitability of ensilage as a means of preserving flax was investigated in a series of experiments in which 400 kg round bales of fresh flax were sealed in polyethylene film or plastic wrapped, with or without the addition of formic acid at 2.5 litre t‐1 or formalin at 5.6 litre t‐1 at the time of baling. Plastic wrapping provided a more effective seal than the bags which were easily punctured by the flax roots resulting in moulding and deterioration of the flax. Where the seal was not broken untreated flax underwent a clostridial fermentation and the pH fell to about 4.8. Cellulolytic activity degraded the flax fibre over a period of 3 to 6 months. The addition of formic acid reduced the cellulolytic activity provided the seal was not broken. In an experiment with 4 kg batches of flax of 65%, 40% or 25% MC sealed in polyethylene film, the addition of formic or propionic acids at 20 g kg‐1 DM did not prevent moulding and deterioration, but both NH3 and SO2 at 40 g kg‐1 DM preserved the physical structure of the flax. The NH3 darkened the flax and made it pliable and unscutchable while the SO2 bleached it and preserved the fibre without microbiological deterioration. The presence of acids on the moist stored flax appeared to inhibit the progress of normal water retting.
Inheritance of partial resistance to bean rust in the common bean (Phaseolus vulgaris L.)
Authors: EDINGTON B R , SHANAHAN P E , LEVIN J , RIJKENBERG F H J 
Published: February 2008

SummaryThe inheritance of partial resistance within eight bean cultivars to a single‐pustule isolate of bean rust was studied by means of a F1 diallel test. General combining ability (GCA) and specific combining ability (SCA) were very highly significant over two seasons and in interaction with seasons. The partitioning of the sums of squares indicated the greater importance of GCA in the inheritance of the resistance. Reciprocal effects were not significant. The estimates of narrow‐sense heritability in the two seasons were 0.899 ± 0.056 and 0.603 ± 0.065.
Immunological techniques used with fungal plant pathogens: aspects of antigens, antibodies and assays for diagnosis
Authors: WERRES SABINE , STEFFENS CLAUDIA 
Published: February 2008

SummaryThe present review surveys serological work with phytopathogenic fungi. Knowledge of antigenic determinants of fungi and the possibilities and problems of selecting and using fungal structures and metabolic products for the production of specific antibodies are considered. The paper is intended to be a source of practical information and literature for the active research worker.
Drought stress and cereal aphid performance
Authors: PONS X , TATCHELL G M 
Published: February 2008

SummaryThe performance of clones of Rhopalosiphum padi and Sitobion avenae from England and Spain was examined on drought‐stressed tillering winter wheat in an environment chamber at 14 ± 1°C. Two different levels of drought stress and an unstressed control were established by different watering regimes which resulted in drought‐stressed plants being smaller at the end of the experiment.The effect of drought stress to plants on aphid performance was not significantly different between the clones tested. Drought stress had no effect on aphid development time, nymphal mortality, the weight of teneral adults and the number of embryos in teneral adults up to the onset of reproduction in the first F1 generation. The subsequent reproductive capacity, as measured by the effective and potential fecundity, and the reproductive rate, were much reduced on drought‐stressed plants. However, there was only a small decrease in the intrinsic rate of increase (rm). Overall the clone of R. padi from Spain performed better than that from England, the development and prereproductive times being shorter and the fecundity higher in the Spanish clone, giving a higher rm. There were no differences in the fecundity and the rm between the Spanish and the English clones of S. avenae. The proportion of the F2 generation that was alate differed greatly between clones, and only the English S. avenae produced significantly more alatae on drought‐stressed than on unstressed plants.
Effect of pea bacterial blight (Pseudomonas syringaepv.pisi) on the yield of spring sown combining peas(Pisum sativum)
Authors: ROBERTS S J , PHELPS K , McKEOWN B M , HEATH M C , COCKERELL V 
Published: February 2008

SummaryField trials to examine the effect of pea bacterial blight(Pseudomonas syringaepv.pisi) (Psp)on the yield of combining peas were carried out at five sites (HRI Wellesbourne, ADAS Rosemaund, ADAS Terrington, PGRO, SASA East Craigs) in the UK in 1990, 1991 and 1992. Healthy seed, cv. Solara, and seed naturally infected withPspRace 2 was sown in large plots (c.200 m2) in the open or under nets to prevent bird damage by pigeons. Despite relatively low disease severity levels (< 15% leaf area) and separation by at least 12 m of cv. Consort (resistant to Race 2) between plots there was considerable spread of disease into plots sown with healthy seed. Regression analysis demonstrated a significant relationship between yield and disease. Of the disease measurements examined, disease severity on the leaves (stipules) at growth stage 208 was found to be the best predictor of yield. A model containing environmental and bird damage terms, in addition to disease, suggested that a yield loss of 0.98 t/ha would be expected for a disease severity score of 1, equivalent to 5% leaf area affected, at growth stage 208.
Characterisation of a variant of zucchini yellow fleck virus (ZYFV), a potyvirus causing a wilt disease of melons in Israel*
Authors: ANTIGNUS Y , LEVY D , COHEN S 
Published: February 2008

SummaryA flexuous filamentous virus 750 nm in length was isolated from field‐grown melons (Cucumis melo L.) and squirting cucumber (Ecballium elaterium L.). Infection of melon seedlings of most commercial varieties resulted in a lethal wilting, but late infections gave dieback. The virus infected systemically all economically important cucurbit crops. Its coat protein consists of a single polypeptide, 34 500 D in size, encapsidating a single stranded RNA genome of 10.1 kb.Antiserum against the Italian zucchini yellow fleck virus (ZYFV) reacted specifically with the Israeli isolate in both ISEM and Western blot. The virus was aphid transmissible in a non‐persistent manner. Based on host range, host reaction and serological data, it is suggested that the virus described is an Israeli variant of ZYFV.
Resistance to cucumber mosaic virus in potato
Authors: VALKONEN J P T , SLACK S A , WATANABE K N 
Published: February 2008

SummaryReactions to two subgroup I isolates (Fny‐CMV and Pf‐CMV) and two subgroup II isolates (A9‐CMV and LS‐CMV) of cucumber mosaic virus (CMV) were studied in three non tuber‐bearing wild potato species (Solanum spp.) of the series Etuberosa, and in two tuber‐bearing interspecific potato hybrids and four potato cultivars using graft‐inoculation. Three classes of phenotypic reactions (susceptible, hypersensitive, extreme resistance) were observed in the tuber‐bearing genotypes. Susceptible genotypes developed mosaic or severe mosaic with leaf malformation and had high CMV titres. Hypersensitive genotypes developed either top necrosis or vein necrosis and/or necrotic spots on apical leaves, and had low CMV titres. Extremely resistant genotypes had no symptoms and no CMV was detected. The hybrid 87HW13.7 (S. tuberosum×S. multidissectum) developed top necrosis specific to infection with Fny‐CMV. The hybrid ‘A6’ (S. demissum×S. tuberosum cv. Aquila) was hypersensitive to all CMV isolates tested. Extreme resistance was not functional against all CMV isolates. Neither hypersensitivity nor extreme resistance were related to the CMV subgroup.
The effects of domestic compost upon the germination and emergence of barley and six arable weeds
Authors: LIGNEAU L A M , WATT T A 
Published: February 2008

SummaryIn a bioassay, leachate from composted household waste was found to decrease both cress germination and the germination of barley and six arable weeds, especially in the light. The effect of compost depth upon the emergence of these species was examined in a glasshouse experiment. Compost had no significant effect on barley emergence. However, weed emergence, particularly of those with small seeds, was reduced greatly by the physical effect of compost and, to a lesser extent, by its chemical effect. The emergence of the large‐seeded species was relatively unaffected by increasing depths of compost, whereas that of the smaller‐seeded weeds steadily decreased, being almost completely prevented by a 3 cm layer. The use of compost to control arable weeds in the field is discussed.
Somatic embryogenesis in pea (Pisum sativum L.): effect of explant, genotype and culture conditions
Authors: van DOORNE L E , MARSHALL G , KIRKWOOD R C 
Published: February 2008

SummaryIn this study 16 cultivars of pea (Pisum sativum L.) were screened in vitro for the formation of somatic embryos which were dependent on the genotype, culture conditions and explant source used. The cultivars Stehgolt, Maro and Progreta showed the highest tendency to form somatic embryos (c. 25%) while Alaska, Rondo and Ascona did not show any embryo production. Using the cultivar Belman, the highest embryo production was achieved by using nodal explants of shoots (10.6%) and a cotyledon‐free embryo as explant source (14.1%) in the light (15.8%) compared to using apices as explants (1.8%) and a seedling as the explant source (9.4%) in the dark (3.3%). Media containing picloram (0.75 mg/litre) followed by BA (1 mg/litre) or kinetin (1 mg/litre), each for four weeks gave the highest somatic embryo production. The development of embryos to whole plants was unreliable and some 90% of the embryos induced did not develop any further, died, recallused or formed secondary embryos. The size of the embryo at separation and the timing of the separation from the original callus were important factors determining success for complete development to whole plant. Regeneration of 184 plants was achieved with ensuing flowering, pod formation and viable seed production from the techniques described.
A survey of black dot and other fungal tuber blemishing diseases in British potato crops at harvest
Authors: READ P J. , STOREY R M J. , HUDSON D R. 
Published: February 2008

SUMMARYBlack dot and other fungal blemishing diseases were assessed on tubers from crops in eastern England in 1987 and 1988, and in 1989 and 1990 from crops throughout Great Britain.Black dot was found on tubers in crops from all areas of the country, and was most common in those from eastern and southern England. The disease was scarce on most Scottish crops, but occasionally some were severely affected. In 1988 there was no consistent relationship between the amounts of disease on the seed and subsequent ware crop. On average, the disease was more prevalent in irrigated crops and where the interval between successive potato crops was short. In 1990 treating seed tubers with fungicide had no effect on subsequent levels of disease.Few crops were unaffected by silver scurf, and it was most common in crops from southern and eastern England. In the national survey common scab was the most prevalent disease, black scurf was less common and skin spot and powdery scab uncommon except in some Scottish crops.
A serological test for detecting Botrytis allii, the cause of neck rot of onion bulbs
Authors: LINFIELD CHRISTINE A. , KENNY SIÂN R. , LYONS N F. 
Published: February 2008

SUMMARYPolyclonal antisera for the immunological detection of Botrytis allii, the cause of onion neck rot, were raised from cell wall and cytoplasmic fractions of the fungus, and from surface plate washings of two isolates of the pathogen. These antisera were used to develop an indirect ELISA for the detection of latent B. allii infection in stored onion bulbs. The antisera did not react with healthy onion tissue and showed only minimal recognition of fungi from other genera. Some cross‐reactivity was observed with B. cinerea but not with other Botrytis spp. tested. In many instances following infection, fungal antigen could be detected earlier by ELISA than by direct culture. In tests on bulbs from a commercial store, the level of B. allii infection was found to be 3.3% by both ELISA and direct plating, but this result was achieved 7 days sooner by ELISA. In field tests, the indirect ELISA gave a good indication at harvest of the probable incidence during storage of neck rot in untreated and artificially inoculated plants, whilst culturing gave results consistently lower than the ELISA until bulbs had been in store for several months, when results for ELISA and culturing were the same. Spores applied to growing plants during the growing season led to greater levels of neck rot than did infested seed, indicating that field debris and waste from cold stores may be more important sources of inoculum in some years than seed contamination.
Shoot growth, radiation interception and dry matter production and partitioning during the establishment phase of Miscanthus sinensis‘Giganteus’ grown at two densities in the UK
Authors: BULLARD M J. , HEATH M C. , NIXON P M I. 
Published: February 2008

SUMMARYPhotosynthetic area index (PAI), radiation interception (I) and dry matter partitioning between shoots and roots were measured for Miscanthus sinensis‘Giganteus' grown from micro‐propagated transplants on a fertile peaty loam soil in eastern England. In the establishment year, Miscanthus plants produced 35 and 70 shoots plant‐1 at densities of 4.0 and 1.8 plants m‐2 respectively. At the higher density, there were 140 shoots m‐2 with the largest reaching a height of 1.8 m; these canopies attained a maximum PAI of 5.45, intercepting 94% of incident radiation. Leaf lamina contributed c. 90% of total photosynthetic area with stems contributing the remainder. At the lower density, maximum PAI and I values were 2.88 and 86% respectively. PAI was related to I by calculating attenuation coefficients (k); these indicated that Miscanthus canopies were more effective at intercepting radiation per unit PAI at the lower density (k= ‐0.31) compared with the higher density (k= ‐0.20). Radiation interception was related to dry matter accumulated by calculating conversion efficiencies (e). At 4 plants m‐2, × for shoot dry matter production was 1.17g MJ‐1. Miscanthus partitioned a relatively large amount of total dry matter into below‐ground biomass. By plant senescence, c. 30% of total dry matter had been partitioned into root and rhizome; rhizome biomass contributed 80% of below‐ground dry matter, × increased to 1.62 g MJ‐1 when calculated on a total dry matter basis (shoot + root + rhizome). Total dry matter production was increased 68% by a 2.2‐fold increase in plant density.
Studies on the effect of protoplast density and genotype mixing on cell regeneration
Authors: GILBERT JULIE E. , SHOHET S. , CALIGARI P D S. 
Published: February 2008

SUMMARYGenotypes of Solanum tuberosum, assessed for their differential response to a protoplast regeneration protocol, were identified. This enabled comparisons to be made in relation to their abilities to regenerate into dividing cells and colonies. Protoplasts from genotypes with contrasting regeneration responses were plated as single or mixed genotype cultures at various plating densities in replicated, randomised experiments, and the effect on the regeneration of particular cell types observed. Protoplasts from single genotype cultures showed intergenotypic variation in the extent of cell regeneration and there were significant effects of genotype mixing and density × genotype mixing interactions. Overall, the effect of mixing was beneficial to a regenerating culture but significant density genotype mixing interactions showed only a positive benefit at the lowest plating density. The protoplast mixing phenomenon was not correlated with the behaviour of the same genotypes at the plantlet level in experiments with in vitro meristem cultures.
The development of Steinernema feltiae (Nematoda Steinernematidae) in the sciarid fly Bradysia paupera (Diptera: Sciaridae)
Authors: GOUGE DAWN H. , HAGUE N G M. 
Published: February 2008

SUMMARYThere was only one generation of Steinernema feltiae in Bradysia paupera. Infection occurred after 3 h, adults developed 27 h after invasion and new infective juveniles (IJ) were produced after 48 h. Stunted females were produced in B. paupera larvae and in other small hosts and these stunted females produced small IJs. The small IJs were capable of infecting hosts and normal sized Us were produced in succeeding generations in Galleria mellonella.
Effect of temperature and diet on hind wing colouration development and elytral hardness of adult Colorado potato beetle (Coleoptera: Chrysomelidae)
Authors: FOLLETT PETER , HILBECK ANGELIKA 
Published: February 2008

SUMMARYThe effects of food and temperature on the development of colour pigment in the hind wings of adult Colorado potato beetle,Leptinotarsa decemlineata(Say), were investigated. In a replicated study, adults were held at 18°C, 28°C and 18/28°C on potato foliage (Solanum tuberosumL.), potato tubers, or without food in controlled‐environment chambers. Representative subsamples of wings were collected at two‐day intervals, mounted on microscope slides, and photographed to document the progression of colour change. Observations were also made on elytral hardening over time.Hind wing colour developed more quickly at 28°C than at 18°C, and after three weeks had attained a deeper red colour at the higher temperature. Colour development was also more rapid when adult beetles were fed on foliage compared with tubers. In foliage‐fed beetles, elytra hardened more quickly at 28°C than 18°C, and many tuber‐fed beetles never developed hardened elytra, regardless of temperature treatment. Unfed beetles developed no hind wing colour pigment and their elytra remained soft for the duration of the experiment. Colour plates documenting wing colour development over time are presented; variation in colour development under the conditions tested, suggests that the use of hind wing colouration to estimate beetle age in the field may be problematic.
Analysis of Microdochium nivale isolates from wheat in the UK during 1993
Authors: PARRY D W. , REZANOOR H N. , PETTITT T R. , HARE M C. , NICHOLSON P. 
Published: February 2008

SUMMARYA total of 144 isolates of Microdochium nivale from stem bases of winter wheat were taken from 30 sites and 91 isolates from grain were taken from seven sites throughout the UK. Identification by polymerase chain reaction (PCR) amplification of the internal transcribed spacer (ITS) region followed by restriction enzyme digestion of the PCR product revealed that 70% of stem base isolates were M. nivale var. majus and 30% var. nivale while 93% grain isolates were var. majus and 7% var. nivale. Almost all isolates were resistant to the benzimidazole fungicide benomyl. Perithecial production in vitro was more common in var. majus isolates and occurred in almost all grain isolates, but was less common in stem base isolates. The implications of the findings in terms of epidemiology and chemical control of this important cereal pathogen are discussed.
Setting confidence limits for the detection of prune dwarf virus in Prunus avium with a monoclonal antibody‐based triple antibody‐sandwich ELISA†
Authors: RAMPITSCH C. , EASTWELL K C. , HALL J. 
Published: February 2008

SUMMARYA triple antibody sandwich enzyme‐linked immunosorbent assay (TAS‐ELISA) with a monoclonal antibody was developed and evaluated for the detection of prune dwarf virus (PDV) in sweet cherry trees (Prunus avium). An independent reverse transcribed polymerase chain reaction test was also developed to establish, in conjunction with a bioassay, the incidence of PDV in 40 sweet cherry trees and to confirm the absence of virus in 15 control trees. Trees with two‐thirds of their leaves positive for PDV would be identified with 99% probability by testing four leaves per tree with TAS‐ELISA. The monoclonal antibody did not cross‐react with Prunus necrotic ringspot virus in the TAS‐ELISA.
Acquisition and transmission of potato mop‐to furovirus by a culture of Spongospora subterranea f.sp. subterranea derived from a single cystosorus
Authors: ARIF M. , TORRANCE L. , REAVY B. 
Published: February 2008

SUMMARYPotato mop‐top virus (PMTV) was detected by ELISA in primary zoospores from four out of six isolates of Spongospora subterranea f.sp. subterranea. One virus‐free isolate (N) of S. subterranea was used to acquire PMTV from potato roots and to transmit the virus to healthy plants. A mono‐fungal culture of S. subterranea (isolate N) was derived by infecting tomato plant roots with a single cystosorus. The culture was used successfully to acquire PMTV from the roots of infected Nicotiana debneyi plants that had been manually inoculated with virus isolates, and subsequently to transmit the virus to healthy bait plants. These experiments confirm that S. subterranea is a vector of PMTV. Two PMTV isolates that had been maintained by manual inoculation for 19 and 21 passages were also acquired and transmitted by the fungus culture.
Observations on the population dynamics of Globodera pallida under single and double cropping conditions
Authors: HALFORD P D. , RUSSELL M D. , EVANS K. 
Published: February 2008

SUMMARYThe population dynamics of Globodera pallida were studied on susceptible potato plants. Oxamyl treated and untreated plots were planted with a G. pallida susceptible crop, from the first early maturity class, under polythene at the end of February and immediately followed, after harvest in June, by a susceptible second crop. Other nematicide treated and untreated plots were sown in April with a G. pallida susceptible cultivar. The results were variable but showed that reproduction of G. pallida under double cropping conditions was greater than on a single main crop.