bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of pre‐storage treatments on mango fruit ripening
Authors: BURDON J N , DORI S , LOMANIEC E , MARINANSKY R , PESIS E 
Published: February 2008

SummaryThe effectiveness of pre‐storage treatments of nitrogen (low oxygen), heat and ethanol and acetaldehyde vapours were examined for their potential for improving mango storage. Mature green mango fruit (Mangifera indica L. cv. Keitt) were treated with low oxygen (< 3% oxygen, 97% nitrogen) for 72 h, acetaldehyde (0.12%) and ethanol (1%) vapours for 24 h or heat (38 ± 2°C) for 48 h prior to storage at 14°C. The nitrogen and ethanol treatments induced substantial levels of acetaldehyde and ethanol in the fruit. Initially the firmness of the nitrogen treated fruit remained higher than the control although later in storage this effect was lost. Differences in ripening were reflected in the total soluble solids and acidity levels, nitrogen maintaining a higher acidity and lower total soluble solids (less mature) whereas the heat treated fruit had lower acidity and higher total soluble solids (more mature). Ethanol and acetaldehyde treatments showed no effect. The use of a pre‐storage treatment of nitrogen therefore had a beneficial effect on retarding ripening, although as storage progressed this effect was lost.
Improved procedures for the in vivo and in vitro production of conidial inoculum of Venturia species of pome fruit
Authors: ROBERTS A L , CRUTE I R 
Published: February 2008

SummaryFull descriptions are provided of a set of improved in vivo and in vitro procedures to allow the efficient production and long‐term storage of conidial inoculum of Venturia species pathogenic on pome fruit. Uniform stands of seedlings inoculated and incubated under standard conditions are used to produce conidial inoculum in vivo, while production in vitro involves establishing a culture on the surface of sterile muslin saturated with 10% malt extract. Conidia retain viability following storage for at least 2 years at ‐20°C. These materials and methods are now used routinely for several types of investigation; they are described together in one publication for the first time and have been shown to provide some advantages over previously reported procedures.
Tuber surface microorganisms influence the susceptibility of potato tubers to late blight
Authors: CLULOW S A , STEWART HELEN E , DASHWOOD E P , WASTIE R L 
Published: February 2008

SummaryPotato tubers (cvs Cara and Bintje) were grown in compost in a glasshouse and immature tubers harvested 57, 68 and 78 days after planting. Two moisture levels were imposed after the first harvest by disconnecting the water supply to one of the treatments and allowing the soil in that treatment to dry naturally. Tubers from wetter compost (59.4% moisture holding capacity) were more resistant to Phytophthora infestans than those from drier compost (14.7% moisture holding capacity) 78 days after planting. The potential causes of this difference were investigated. Aqueous extracts of wet compost did not inhibit the growth of P. infestans. The susceptibility of the internal tuber tissue, from which the periderm had been removed, was different to whole tuber susceptibility. The internal tissue of tubers from wet compost was more susceptible (cv. Cara), or as susceptible (cv. Bintje) as that of tubers from dry compost 78 days after planting. Fungi were isolated from the surface of whole tubers and there were no differences between the populations of potentially antagonistic fungal genera on tubers from wet and dry compost. As the experiment progressed, the number of bacteria per gram fresh weight on tubers grown in wet compost increased, whereas that on tubers from drier compost decreased (cv. Bintje) or remained similar (cv. Cara). There were significantly (P= 0.008) more bacteria on the surface of tubers from wet compost 78 days after planting. When P. infestans was co‐cultured in Petri dishes with randomly selected tuber surface bacteria, some isolates (≤ 16.7%) inhibited the growth of the fungus. The percentage of the total bacterial population that was antagonistic to P. infestans was not significantly affected by soil moisture level (P= 0.368). The greater numbers of bacteria, of which a proportion are antagonistic to P. infestans, on the surface of tubers grown in wet compost may account for the greater resistance to tuber blight in that instance.
Surveys of stem base diseases and fusarium ear diseases in winter wheat in England, Wales and Scotland, 1989–1990
Authors: POLLEY R W , TURNER J A 
Published: February 2008

SummaryAn investigation into the incidence of stem base diseases and the pathogens associated with them was undertaken on winter wheat samples collected at growth stages 31 and 73–75 in 1989 and 1990. Symptoms at growth stage 31 were classified into 10 different types based on visual characteristics. Although Pseudocercosporella herpotrichoides was associated mainly with eyespot lesions and Rhizoctonia spp. with sharp eyespot lesions, a significant number of isolates of each pathogen were taken from lesions classified as fusarium. Different types of fusarium lesion on stem bases at both growth stages were not associated with any one particular Fusarium or Microdochium species. 98% of P. herpotrichoides isolates obtained from eyespot lesions at growth stage 31 in 1989, and 87% of those obtained in 1990 were identified as the sub‐species P. herpotrichoides var. acuformis, Microdochium nivale was more common than any of the Fusarium species at both growth stages, and was particularly prevalent in samples from Scotland at the earlier growth stage in 1989. Isolations from the top internodes at growth stage 73–75 indicated that systemic infection by Fusarium species, although present in some stems, was of little importance. Fusarium ear blight affected 0.4% of ears in 1989 and 0.5% in 1990. Glume spot lesions on the ears in 1990 were predominantly associated with Fusarium poae.
Characterisation of a labile RNA virus‐like agent from white clover
Authors: GARDINER T J , PEARSON M N , HOPCROFT D H , FORSTER R L S 
Published: February 2008

SummaryA labile virus has been identified in white clover in New Zealand. The virus was mechanically transmitted to nine species of herbaceous test plants. No virus‐like particles were identified by electron microscopy in ultrathin sections or in negatively stained sap extracts, although in infected Chenopodium quinoa there were prominent membraneous inclusion bodies in the cell cytoplasm and membrane‐bound structures c. 50 nm in diameter associated with the tonoplast in cell vacuoles. Double‐stranded RNA species of approximately 6800, 3500 and 3300 bp were isolated from infected tissues. DsRNA denatured by boiling was infectious to C. quinoa, but undenatured dsRNA was not infectious. Total nucleic acid preparations from infected leaves were highly infective without boiling, indicating that most of the infectivity was single‐stranded RNA. Infectivity was recovered in the poly (A)‐ faction following oligo (dT)‐cellulose chromatography, indicating that the RNA probably lacks a 3′ tract of poly (A). The labile white clover virus is tentatively named white clover virus L (WCIVL).
Effect of host plant resistance and chemical control of the head bug, Calocoris angustatus Leth., on grain quality and seedling establishment in sorghum
Authors: SHARMA H C , SOMAN P , SUBRAMANIAN V 
Published: February 2008

SummaryThe sorghum head bug, Calocoris angustatus Lethiery (Hemiptera: Miridae), is one of the most important pests of grain sorghum in India. Studies were conducted to quantify the effect of head bug damage on grain quality and seedling establishment on head bug‐resistant cultivars (IS 17610 and IS 21443), a moderately susceptible cultivar (IS 9692), and a susceptible commercial cultivar (CSH 11). Differences in 1000‐grain mass, seed germination and percentage of floaters were significant between protected and unprotected plots in CSH 11 and IS 9692, but not in IS 17610 and IS 21443. Grain damage ratings were significantly lower in IS 17610 than in IS 9692 and CSH 11 across different protection levels.Head bug‐damaged grain had greater protein content than the undamaged grain, possibly because of depletion in starch, and a marginal increase in soluble sugars. Amounts of proline and tyrosine were greater in the bug‐damaged grain than in the undamaged grain, while the reverse was true for aspartic acid, methionine, leucine and lysine. Head bug damage also increased the tannin content in IS 9692 (which is a high‐tannin genotype).Moisture regimes and insecticide protection levels significantly affected seedling emergence. Seedling emergence of CSH 11 was lower than that in IS 17610. In the latter genotype, the differences between protected and unprotected plots were not significant. Head bug damage thus not only leads to quantitative loss in grain yield, but also spoils the grain quality and renders the grain unfit for seed purposes. These qualitative effects should be taken into account while estimating losses due to bug damage and determining economic thresholds.
Two methods for the prediction of Mycocentrospora acerina infection on stored carrots
Authors: HERMANSEN ARNE , AMUNDSEN TERJE 
Published: February 2008

SUMMARYCarrot plants were collected from 26 fields located in different districts in Norway during 1985, 1986 and 1987. Leaves were sampled in the first two years, and roots were sampled in all years. Incidence of Mycocentrospora acerina on the leaves at harvest was correlated (r = 0.82) to the incidence of M. acerina on the roots after storage at 0–1°C for six months (long term storage). Incidence of M. acerina on roots sampled about six weeks before harvest (date c) and placed at 10°C for six weeks (test storage) was correlated (r = 0.84) to incidence of the pathogen after long term storage on roots sampled at harvest (date d). Test storage and long term storage data from parallel samples taken at date d was more strongly correlated (r = 0.90).
Effects of sowing date and vernalisation on the growth of winter barley and its resistance to powdery mildew (Erysiphe graminis f.sp. hordei)
Authors: WHITE N. , JENKYN J F. 
Published: February 2008

SUMMARYDetailed studies on the production of individual leaves, and the development of powdery mildew on them, were made in field plots of winter barley sown on different dates. The greater severity of the disease on early‐sown than on later‐sown seedlings during the autumn and winter can probably be explained mainly by changes in the abundance of inoculum and the suitability of the weather for infection. Results from glasshouse experiments suggest that the differences may be reinforced by direct effects of vernalisation on the susceptibility of seedlings to the disease. Contrary effects of sowing date on mildew severity during summer are probably due to the progressively greater resistance to mildew of the later‐formed than of seedling leaves, and the earlier appearance of corresponding leaves on early‐sown than on later‐sown plants. Early sowing can also increase the total number of leaves produced per stem. Therefore, because resistance of the leaves increases progressively, the maximum degree of resistance expressed by the later‐formed (e.g. flag) leaves will often be greater on early‐sown than on later‐sown plants.
Endophytic bacterial systems governing red clover growth and development
Authors: STURZ A V. , CHRISTIE B R. 
Published: February 2008

SUMMARYEndophytic competent bacteria capable of promoting both beneficial and detrimental growth responses in red clover (Trifolium pratense L.) were recovered from three adjacent areas of farmland each having a different cropping history — continuous red clover, continuous potatoes (Solanum tuberosum L.) or a 2 yr rotation of red clover and potatoes. The population composition of these rhizobacteria was altered by the various crop sequences. The greatest instance of significant growth responses (beneficial or detrimental) occurred with those bacteria derived from the clover‐potato soil, suggesting increased interactive ‘competition’ among bacterial populations at the ‘interface’ between different crop rotations. Whether bacterial strains promoted or inhibited growth appeared to depend on the cropping history and prior exposure of pre‐bacterised clover plants to the natural microflora in the peat‐based growing media. The interaction between bacterial colonists influenced plant trait expression to the degree that some characteristics were completely masked. Improvements in plant growth were interpreted as an allelopathic side‐effect of the competition between endophytes for the same ecological niche, from which the plant inadvertently benefits.
Use of isoenzyme and protein phenotypes to discriminate between six Pratylenchus species from Great Britain
Authors: IBRAHIM S K. , PERRY R N. , WEBB R M. 
Published: February 2008

SUMMARYSix species of Pratylenchus indigenous to Great Britain, P. crenatus, P. fallax, P. neglectus, P. penetrans, P. pinguicaudatus and P. thornei were analysed by slab gel electrophoresis to compare protein patterns and isoenzyme phenotypes of esterase, glucose‐6‐phosphate dehydrogenase, isocitrate dehydrogenase, phosphoglucose isomerase and phosphoglucomutase. Multiple electromorphs were obtained from all enzymes examined. The results demonstrated that isoenzyme phenotypes are useful to supplement the morphological characterisation of these nematode species. Pair‐wise comparisons of the six species were performed giving coefficients of similarity in the range 11–41%. A dendrogram of the six species, generated from the five enzyme banding patterns, gave two groups: group 1 contained P. pinguicaudatus, P. fallax and P. thornei and group 2 contained P. penetrans, P. neglectus and P. crenatus.
Postharvest treatments against Western Flower Thrips [Frankliniella occidentalis (Pergande)] and Melon Thrips (Thrips palmi Karny) on orchids
Authors: MANN J A. , TATCHELL G M. , DUPUCH M J. , HARRINGTON R. , CLARK S J. , McCARTNEY H A. 
Published: February 2008

SUMMARYPostharvest treatments, including insecticidal dips, isopropyl alcohol dips, insecticidal fogs and hot‐water immersion, were evaluated to control mixed infestations of Western Flower Thrips (Frankliniella occidentalis) and Melon Thrips (Thrips palmi) on dendrobium orchid blossoms. The limiting factor for all postharvest treatments was phytotoxicity, characterised by a loss of vase life that differed among cultivars. Insecticidal dips and insecticidal fogs were less phytotoxic than hot‐water immersion and isopropyl alcohol dips. Insecticidal fogs consisting of abamectin 2.0% e.c. and abamectin tank‐mixed with Pyrenone e.c. (6% pyrethrins, 60% piperonyl butoxide) reduced the mean number of thrips per blossom by 93.8% and 92.3%, respectively and were nonphytotoxic. An insecticidal aerosol, Floragas (2% permethrin and 0.1% pyrethrum dissolved in high pressure liquified CO2) reduced thrips by 33% to 54% with no phytotoxicity. Insecticidal dips for 3 min with agitation reduced the mean number of thrips per blossom by 43.7% to 99.1%. Of the 12 insecticides and one surfactant tested, only chlorpyrifos 44.4% e.c., fluvalinate 22.3% f., and chlorpyrifos 50% d.f. were both effective and nonphytotoxic. Immersion in water at 49.5°C for 15 and 20 s reduced the mean number of thrips per blossom by 88.1% and 95.3%, respectively. A 70% solution of isopropyl alcohol applied as a postharvest dip did not kill all thrips and was extremely phytotoxic to blossoms.
Effects of fungicides on the growth and conidial germination of Colletotrichum coccodes and on the development of black dot disease of potatoes
Authors: READ P J. , HIDE G A. 
Published: February 2008

SUMMARYThe effects of 10 fungicides on the growth of Colletotrichum coccodes in agar culture and on the germination of conidia was investigated. In field experiments in 1990 and 1991 the extent to which treating black dot‐affected potato seed tubers with fungicides affected the development of the disease on stem bases, roots and tubers was assessed. Black dot was also assessed on plants from field trials in 1990 which were designed to investigate the efficacy of the soil sterilant 1,3‐dichloropropene (Telone) and two nematicides, aldicarb (Temik) and ethoprophos (Mocap).Prochloraz and fenpiclonil were the most effective fungicides in decreasing the size of C. coccodes colonies on agar. Imazalil, propiconazole and dichlorophen were also effective, but at higher concentrations, whereas tolclofos‐methyl, thiabendazole and benomyl were only moderately effective. Resistant sectors developed from inhibited colonies on agar containing fenpiclonil and tolclofos‐methyl. Conidial germination was prevented at 1 mg/litre fenpiclonil and 5 mg/ litre dichlorophen; imazalil, benomyl and thiabendazole were also moderately effective.Fenpiclonil and propiconazole seed tuber treatments consistently decreased black dot infection on roots, stem bases and daughter tubers early in the season, but only fenpiclonil decreased disease on tubers at harvest in October. Propiconazole also delayed emergence and decreased stem numbers. Soil treatment with 1,3‐dichloropropene, aldicarb or ethoprophos had no effect on black dot but Rhizoctonia solani tuber infection and black scurf were increased.
Biology of the hop cyst nematode Heterodera humuli
Authors: MENDE N VON , McNAMARA D G. 
Published: February 2008

SUMMARYIn an intensively sampled English hop garden, cysts of Heterodera humuli were found in every sample taken. Most occurred in the top 15 cm of soil, decreasing in number by half with every 15 cm in depth. Numbers of second‐stage juveniles fluctuated during the vegetative period in a pattern which indicated that more than one generation, possibly two to three, were produced. The generation time was about 1.5 months. In pot experiments under controlled conditions (20°C; 16 h light/day) the life cycle lasted 40 days. The optimal temperature was 20°C for the development of H. humuli in the roots of its host Humulus lupulus. Most H. humuli juveniles invaded hop roots at 15°C, but egg hatch was greatest at 20°C. In moist soil, second‐stage juveniles survived for at least 54 days and thereafter invaded roots and reproduced.
The first record of the root‐endoparasitic nematode Zygotylenchus guevarai in Britain
Authors: BARKER A D P. , HOOPER D J. 
Published: February 2008

SUMMARYThe root‐endoparasitic nematode Zygotylenchus guevarai is recorded for the first time in Britain. It occurred in soil from a crop of glasshouse grown Alstroemeria in West Sussex, England.
Detection of cross reactive antigens between Pestalotiopsis theae and tea leaves and their cellular location
Authors: CHAKRABORTY B. N. , BASU P. , DAS R. , SAHA A. , CHAKRABORTY U. 
Published: February 2008

SummaryAmong the 12 varieties of tea tested against three isolates of Pestalotiopsis theae, causal agent of grey blight disease, Teen Ali‐17/1/54 and TV‐23 were found to be highly susceptible while CP‐1 and TV‐26 were resistant under identical conditions. Leaf antigens were prepared from all the tea varieties, three isolates of P. theae and a non‐pathogen of tea (Bipolaris tetramera). Polyclonal antisera were raised against mycelial suspensions of P. theae (isolate Pt‐2) and leaf antigens of Teen Ali‐17/1/54 and CP‐1. These were compared an immunodiffusion test and enzyme‐linked immunosorbent assay to detect cross reactive antigens (CRA) shared the host and the parasite. CRA were found among the susceptible varieties and isolates of P. theae (Pt‐1, 2 and 3). Such antigens were not detected between isolates of P. theae and resistant varieties, B. tetramera and tea varieties or isolates of P. theae. Indirect staining of antibodies using fluorescein isothiocyanate (FITC) indicated that in cross sections of tea leaves, the CRA was concentrated in the epidermal cells and mesophyll tissues. CRA was present in the young hyphal tips of the mycelia and on the setulae and appendages of the conidia of P. theae.
Cavity spot of carrots: Interactions between the host and pathogen, related to the cell wall
Authors: ZAMSKI E. , PERETZ I. 
Published: February 2008

SummaryThis study investigates the structural aspects of cavity spot pathogenesis. Different Pythium spp. isolated from infected carrots, apples and melons were cultured on agar in Petri dishes and used for inoculation of uninfected carrots. Only slow‐growing Pythium spp. (< 15 mm day‐1), such as P. violae and P. sulcatum caused cavity spot lesions. It is suggested that slow‐growing species are able to penetrate, albeit slowly, into the plant tissue for 3 to 4 days before a hypersensitive reaction develops. Fast‐growing species, however, did not cause lesions. Based on ultrastructural observations, we suggest that the following sequence of events occurs between the plant and the pathogen: The fungus infects the walls and grows for several days, during which time small amounts of wall‐degrading enzymes are secreted. Phenylalanine ammonia lyase (PAL) activity and phenols increase linearly immediately upon inoculation. There was a lag phase of about 5 days before lignin began to increase linearly for about a month. Dissolution of wall components decreases the solute potential and water potential in the apoplast. Thus, water moves from the symplast into the apoplast, the turgor pressure gradually dissipates, and the cells shrink and eventually die.
Occurrence of Verticillium dahliae on sunflower (Helianthus annus) in the UK
Authors: CHURCH V. J. , McCARTNEY H. A. 
Published: February 2008

SummaryIn August 1994 verticilliosis‐like symptoms were noticed in a maturing crop of sunflower at IACR‐Rothamsted. Wilting plants with chlorotic areas on some leaves, and dark areas of microsclerotia at the base of stems, were first observed on 11 August. As the plants matured, dark stripes were also observed on the stems. Many stems became brittle and later collapsed. Infected xylem showed a brown discolouration, later turning to black, and microsclerotia developed. Verticillium dahliae was isolated from all parts of the plant.In general, once symptoms were present, the incidence of verticilliosis‐affected plants increased, and the disease developed, more rapidly in early maturing varieties than in the later maturing types. At harvest, incidence ranged between 24.5% and 89.8%, depending on variety. Early maturing varieties appeared to be more susceptible than later maturing types.Isolates of V. dahliae were cultured in the laboratory. Sunflower plants were artificially inoculated with these isolates and developed verticilliosis symptoms when grown under controlled environmental conditions.
Specific detection of the Andean strain of potato virus S monoclonal antibodies
Authors: ČEřOVSKÁ N. , FILIGAROVÁ M. 
Published: February 2008

SummaryFour mouse monoclonal antibodies (MAbs) specific for the Andean strain of potato virus S (PVSA) were produced. The MAbs reacted with four isolates of PVSAbut did not react with four isolates of ordinary strain of PVS (PVSO). The MAbs did not react with six other members of the Carlavirus group including potato virus M. A MAb‐based ELISA, using MAbs (IEB‐1 and IEB‐4‐AP), was devised and shown to specifically detect PVSA.