bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serological relatedness of strains of maize dwarf mosaic and sugarcane mosaic viruses as determined by microprecipitin and enzyme‐linked immunosorbent assays
Authors: JARJEES M. M. , UYEMOTO J. K. 
Published: February 2008

SUMMARYAntisera to maize dwarf mosaic virus strain A, B, and Kansas 1 (MDMV‐A, ‐B, ‐KS1) and sugarcane mosaic virus strains A, B, D, and H (SCMV‐A, ‐B, ‐D, ‐H) were prepared and their reactions with these and other SCMV strains (SCMV‐I, ‐J, ‐M) compared by microprecipitin tests and enzyme‐linked immunosorbent assay (ELISA). In microprecipitin tests, antibody titres in heterologous tests were unchanged or up to five two‐fold dilution steps lower than those in corresponding homologous reactions. Microprecipitin tests and ELISA distinguished the same four serogroups among the 10 viruses tested. Strains MDMV‐A and SCMV‐J comprised one serogroup; MDMV‐KS1, a second; MDMV‐B and SCMV‐A, ‐B and ‐D, a third; and SCMV‐H, ‐I and ‐M, a fourth.
The relationship between neutral lipid reserves and infectivity for hatched and dormant juveniles of Globodera spp.
Authors: STOREY R. M. J. 
Published: February 2008

SUMMARYA quantitative histochemical technique based on scanning microdensitometry has been used to investigate neutral lipid utilisation by hatched and dormant juveniles of Globodera rostochiensis and Globodera pallida.During storage in water at 20°C, hatched juveniles of the two species showed no statistical difference in their rate of lipid utilisation. A semi‐logarithmic curve fitted to the pooled data suggests that 50% relative utilisation occurred after 36 ± 4 days of storage. Measurement of the neutral lipid reserves for unhatched juveniles of G. pallida dormant in field soils in Northern England for a maximum of 14 yr showed a reduced rate of metabolism with a 50% loss of neutral lipid reserves after 7·5 ± 1·1 yr.The use of neutral lipid reserves by the hatched, starved juveniles was correlated with their survival and with a loss of both locomotor activity and an ability to infect tomato seedlings. Furthermore, results suggest that a loss of mobility by juveniles from field populations of G. pallida immediately after hatching was more closely related to their neutral lipid reserves than the duration of their dormancy. Infection of plants was also reduced for one population. This suggests that measurement of the neutral lipid reserves of a population may be of value for modifying the economic threshold to take account of changes in infectivity during prolonged rotations.
Effect of time of staking on the development of anthracnose disease and yield of water yam (Dioscorea alata)
Authors: NWANKITI A. O. 
Published: February 2008

SUMMARYUnstaked and late staked yam vines were much more affected with anthracnose disease than those staked during the first 63 days of growth in a susceptible cultivar but not in a resistant one. However, yields of both cultivars were much less on unstaked or late staked yams, probably because unstaked vines suffered from leaf shading and high soil temperatures.
Influence of Vitis source on in vitro shoot apex culture
Authors: FANIZZA G. , TANZARELLA O. A. , CARROZZO G. , GRECO B. 
Published: February 2008

SUMMARY In vitro tip culture of grapevine was successful when the tips were removed from glasshouse or shadehouse plants but most of those removed from field grown plants and treated in a similar manner died within 2 days.
Properties of broad bean yellow band virus, a possible new tobravirus
Authors: RUSSO M. , GALLITELLI D. , VOVLAS C. , SAVINO V. 
Published: February 2008

SUMMARYA virus was transmitted from broad bean plants in Apulia (Southern Italy) with leaves showing yellow rings, line patterns or yellow vein banding and malformations and necrosis of pods. Symptoms in some, but not all, test plants were similar to those induced by tobraviruses. Purified virus preparations contained two classes of rod‐shaped particles containing c. 5% nucleic acid with sedimentation coefficients of 186S and 276S. After centrifugation to equilibrium in CsCl gradients, two components were resolved, with buoyant densities of 1·298 and 1·316 g/cm3. Unfractionated virus preparations contained two species of single‐stranded RNA with mol. wts of c. 1·06 × 106 and 2·48 × 106 and one species of coat protein with mol. wt of c. 21 300. The modal lengths of the two classes of particles, both in plant sap and in purified preparations, were 77 nm (S particles) and 202 nm (L particles). L particles accumulated in infected cells in paracrystalline aggregates, whereas S particles were randomly distributed in the cytoplasm of cells. The virus was serologically unrelated to two isolates of tobacco rattle virus and two isolates of pea early‐browning virus. The virus, named broad bean yellow band, is considered a distinct tobravirus.
Anther culture in Brussels sprouts (Brassica oleracea var. gemmifera)
Authors: OCKENDON D. J. 
Published: February 2008

SUMMARYIn Brussels sprouts, yields of up to 357 embryos per 100 anthers cultured were obtained using a thermal shock treatment of 16 h at 35°C at the start of the culture period. Treatments of 48 h at 35°C and 14 days at 30°C gave no embryos. The F1 hybrid cv. Gower consistently gave higher embryo yields than the F1 hybrid cv. Nym, the differences being 3 to 10‐fold. Differences in embryo yield of 3‐fold or less were usually not statistically significant because of great variation within a treatment. This variation was less with donor plants raised in a growth room than with those raised in a glasshouse, where temperature and light intensity could not be so accurately controlled.From 842 embryos cultured, 270 plants were regenerated, mostly via hypocotyl explants, which developed from the anther‐derived embryos. Most of the regenerants were haploid or diploid, with a few of higher ploidy.
The effects of grading and ‘priming’ seeds of crisp lettuce cv. Saladin, on germination at high temperature, seed ‘vigour’ and crop uniformity
Authors: WURR D. C. E. , FELLOWS JANE R. 
Published: February 2008

SUMMARYThree seedlots of crisp lettuce cv. Saladin were ‘primed’ in 1% tri‐potassium orthophosphate (K3PO4) or in water for 6 to 12 h and then dried at room temperature. Two of the seedlots were separated into fractions of different mean weight before ‘priming’. The effects of ‘priming’ and grading on crop uniformity, germination at 35°C and root length in a slant test were evaluated.In general, ‘priming’ increased root length in a slant test but there were no consistent beneficial effects of ‘priming’ on seedling size, head weight or uniformity of head weight. Larger seed produced longer roots in a slant test than small seed and gave larger seedlings but seed size had no effect on head weight or cv. of head weight. ‘Priming’ had no effect on germination at 20°C but significantly increased germination at 35°C. ‘Priming’ in K3PO4 was more effective than in water. It is suggested that the response of seeds to ‘priming’ varies with seedlot and individual seed weight.
Detection of aphid remains in predatory insects and spiders by ELISA
Authors: CROOK NORMAN E. , SUNDERLAND KEITH D. 
Published: February 2008

SUMMARYAn ELISA was developed which would detect and quantify ingested aphids in predators found in and around cereal crops. The detection limit of the assay was less than one hundredth of an homogenised adult aphid. Tests with 13 species of aphid showed that those which had been used as the principal immunogens reacted most strongly in the assay. Nearly a hundred species of invertebrates, both predators and alternative prey, have been tested in the assay and no evidence of significant cross‐reaction was found with any of these species or with a number of samples of plant material on which aphids may be found. Aphid material could still be detected in predators which had been stored for up to 7 days in 4% formalin or 70% ethanol.
Effect of maize stunting mollicutes on survival and fecundity of Dalbulus leafhopper vectors
Authors: MADDEN L. V. , NAULT L. R. , HEADY S. E. , STYER W. E. 
Published: February 2008

SUMMARYThe effect of corn stunt spiroplasma (CSS) on survival and fecundity of three Dalbulus leafhopper species was determined. CSS significantly reduced the survival, as measured by the time to 50% (t50) and 25% (t25) survival, and by the scale parameter (b) of the Weibull model, for D. elimatus and D. gelbus. Fecundity of these two species, as measured by the net and gross reproductive rates, was also reduced by CSS. CSS did not significantly affect the corn leafhopper, D. maidis. In a separate experiment, maize bushy stunt mycoplasma (MBSM) reduced the survival and fecundity of D. maidis at temperatures from 20 to 29 °C. The effect of MBSM on D. maidis survival was less severe than CSS on D. elimatus and D. gelbus; t25, but not t50, was reduced by MBSM. Survival times and the cohort generation time generally declined with increasing temperature. Fecundity, however, generally increased with increasing temperature.
Evaluation of selective media for the isolation ofFusarium solanivar.coeruleumandFusarium sulphureumfrom soil and potato tuber tissue
Authors: JEFFRIES C. J. , BOYD A. E. W. , PATERSON L. J. 
Published: February 2008

SUMMARYA new selective medium containing pentachloronitrobenzene and 2‐aminobutane (the PAB medium) was developed for soil‐dilution plate enumeration of fungal propagules ofFusarium solanivar.coeruleumandF. sulphureumfrom field soil. Growth of ‘weed‐fungi’ was less on the PAB medium than on the previously developedF. solanivar.coeruleumisolation medium (the PM70 medium) and significantly more propagules ofF. solanivar.coeruleumwere detected.Propagule counts (x) ofF. solanivar.coeruleumandF. sulphureumfrom the PAB medium, after log10(x/10 + 1) transformation, were linearly related to the angular transformation of measurements of soil infectivity from the tuber bait method using the susceptible cv. Catriona. Slopes from disease‐inoculum regressions forF. solanivar.coeruleumandF. sulphureumin November and May were similar and this suggests that the mode of pathogenic action ofF. solanivar.coeruleumandF. sulphureumwas similar. Recently harvested tubers, inoculated in November, however, were more resistant to infection by both pathogens than stored tubers inoculated in May. Storage of air dry soil at 4°C for 6 months reduced the population ofF. sulphureumbut not the population ofF. solanivar.coeruleum.Whereas the PAB medium is recommended primarily for use in the isolation ofF. solanivar.coeruleumandF. sulphureumfrom field soil, the PM70 medium appears to be more suitable for recovery of these pathogens and others, includingPhoma exiguavar.foveatafrom diseased tuber tissue.
Detection of strains of African cassava mosaic virus by nucleic acid hybridisation and some effects of temperature on their multiplication
Authors: ROBINSON D. J. , HARRISON B. D. , SEQUEIRA J. C. , DUNCAN G. H. 
Published: February 2008

SUMMARYDNA probes, made by cloning double‐stranded forms of each of the genome parts (DNA‐1 and DNA‐2) of the Kenyan type isolate of African cassava mosaic virus (ACMV‐T), reacted strongly with extracts from Nicotiana benthamiana plants infected with ACMV‐T, or with Angolan or Nigerian isolates that are closely serologically related to the type isolate. However, only the DNA‐1 probes reacted with extracts of TV. benthamiana infected with a Kenyan coast isolate (ACMV‐C), which is serologically less closely related to ACMV‐T. DNA‐1 and DNA‐2 probes also reacted with extracts of mosaic‐affected Angolan cassava plants, including some which have not yielded ACMV particles detectable by immunosorbent electron microscopy and from which virus isolates have not been transmitted to TV. benthamiana. These anomalous plants, unlike other naturally infected cassava plants, showed mosaic symptoms on all their leaves which, however, contained only traces of virus particle antigen detectable by enzyme‐linked immunosorbent assay. They contain isolates of ACMV that are probably defective for particle production.ACMV‐T particles accumulated optimally in N. benthamiana at 20–25°C. At 30°C fewer particles, which apparently had a slightly greater specific infectivity, were produced. At 15°C, considerable quantities of virus particle antigen, virus DNA and virus particles were produced but the particles were poorly infective, and the few that could be purified contained an abnormally large proportion of polydisperse linear DNA molecules, and fewer circular molecules than usual. Angolan isolates, whether particle‐producing or not, likewise replicated better in cassava plants at 23 °C than at 30 °C. In contrast, ACMV‐C attained only very low concentrations in N. benthamiana, but these were greater at 30 °C than at 23°C.
Peanut stripe virus ‐ a new seed‐borne potyvirus from China infecting groundnut (Arachis hypogaea)1
Authors: DEMSKI J. W. , REDDY D. V. R. , SOWELL G. , BAYS D. 
Published: February 2008

SUMMARYA new virus, peanut stripe (PStV), isolated from groundnut (Arachis hypogaea) in the USA, induced characteristic striping, discontinuous vein banding along the lateral veins, and oakleaf mosaic in groundnut. The virus was also isolated from germplasm lines introduced from the People's Republic of China. PStV was transmitted by inoculation of sap to nine species of the Chenopodiaceae, Leguminosae, and Solanaceae; Chenopodium amaranticolor was a good local lesion host. PStV was also transmitted by Aphis craccivora in a non‐persistent manner and through seed of groundnut up to 37%. The virus remained infective in buffered plant extracts after diluting to 10‐3, storage for 3 days at 20°C, and heating for 10 min at 60°C but not 65°C. Purified virus preparations contained flexuous filamentous particles c. 752 nm long, which contained a major polypeptide of 33 500 daltons and one nucleic acid species of 3·1 × 106 daltons. In ELISA, PStV was serologically related to blackeye cowpea mosaic, soybean mosaic, clover yellow vein, and pepper veinal mottle viruses but not to peanut mottle, potato Y, tobacco etch, and peanut green mosaic viruses. On the basis of these properties PStV is identified as a new potyvirus in groundnut.
Observations on the invasion and development of the pea cyst‐nematode Heterodera goettingiana in winter field beans (Vicia faba)
Authors: BEANE J. , PERRY R. N. 
Published: February 2008

SUMMARYA plot experiment to investigate the invasion, development and number of generations of Heterodera goettingiana on winter‐sown field beans showed that, although second‐stage juveniles invaded in October, white females did not appear until mid‐May and only one generation occurred. The results are discussed in the context of temperature requirements for the development of this nematode.
Observations on the introduction of Verticillium chlamydosporium and other parasitic fungi into soil for control of the cereal cyst‐nematode Heterodera avenue
Authors: KERRY B. R. , SIMON A. , ROVIRA A. D. 
Published: February 2008

SUMMARYIsolates of Verticillium chlamydosporium and a sterile fungus added to soil on ground oat grain reduced the numbers of Heterodera avenae on wheat by between 26 and 80%. Nematode populations in uninoculated soil increased from 15 eggs/g soil before planting to 218 eggs/g after harvest. V. chlamydosporium was isolated from oat grain that had been air‐dried and milled before introduction into soil. Applications of the fungi on attapulgite clay or as suspensions of mycelium and spores in water had no effect on nematode multiplication. The effect of the fungi on numbers of H. avenae eggs was similar in autoclaved and non‐sterilised soil. V. chlamydosporium added on attapulgite clay to a calcareous sand and a calcareous silty loam could be re‐isolated after at least 6 months. Some isolates colonised the roots of wheat without causing lesions or affecting the dry weights of shoots or roots. These results indicate that V. chlamydosporium may be useful for the biological control of cyst nematode pests.
Expression of genes for resistance to potato virus Y in potato plants and protoplasts
Authors: BARKER H. , HARRISON B. D. 
Published: February 2008

SUMMARYPlants of several potato clones with major gene resistance to potato virus Y (PVY) developed necrotic local lesions and systemic necrosis after manual inoculation with common (PVYo) or veinal necrosis (PVYN) strains of the virus. The clones reacted similarly, although their resistance genes are thought to be derived from four different wild species of Solarium. Mesophyll protoplasts from each clone became infected when inoculated with RNA of PVYo by the polyethylene glycol method. The proportion of protoplasts infected, assessed by staining with fluorescent antibody to virus particles, was similar to that of protoplasts of susceptible potato cultivars.In contrast, plants of potato cultivars Corine and Pirola, which possess gene Ry from S. stoloniferum, developed few or no symptoms when manually inoculated or grafted with PVYo. Moreover, only very few protoplasts of these cultivars produced virus particle antigen after inoculation with PVYo RNA. The extreme resistance to PVY of cvs Corine and Pirola was therefore expressed by inoculated protoplasts whereas the resistance of the necrotic‐reacting potato clones was not.
Further studies on the slant test as a measure of the vigour of crisp lettuce seedlot
Authors: WURR D. C. E. , FELLOWS JANE R. 
Published: February 2008

SUMMARYMeasurements of seed vigour, emergence and maturity characters were made on six seedlots of crisp lettuce cvs Pennlake and Saladin, vigour being determined by the measurement of root length in a slant test.There were significant differences between the root length and transplant weight of different seedlots of each cultivar. Root length was significantly rank‐correlated with transplant dry weight in both cultivars (cv. Pennlake rs= 0·94, N = 6; cv. Saladin rs= 0·83, N = 6) but not with head weight at maturity. Percentage germination was significantly correlated with seed weight and root length. It is suggested that the slant test can be reliably used to indicate early plant vigour.
The effect of temperature and wind on the flight activity of cereal aphids
Authors: WALTERS K. F. A. , DIXON A. F. G. 
Published: February 2008

SUMMARYThe lower temperature threshold for take‐off inSitobion avenaeobtained from an analysis of daily 12·2 m suction trap catches was 16°C. In the laboratory, the take‐off threshold forS. avenaewas 17·5°C in increasing temperatures, but 19°C when aphids were kept at constant temperatures for a short period of time. The equivalent thresholds were both 20·5°C forMetopolophium dirhodum.Over a period of 16 h noS. avenaetook‐off from plants at 10°C, 70% at 15°C and all within 16 h at 20°C. It was concluded that suction trap catches can be used to compare the temperature thresholds for take‐off of both different species and morphs of a species of aphid. Emigrants ofRhopalosiphum padi, but not ofM. dirhodum, took‐off at a higher temperature than the alate exules.High winds were found to delay but not inhibit take‐off both in the field, and in the laboratory, using both artificial and plant substrates. All aphids eventually flew, even from favourable hosts.It was concluded that adverse weather conditions will delay but not prevent cereal aphid migration in early summer.
Sporulation of Septoria nodorurn (and S. tritici) on spring wheat cvs Kolibri and Maris Butler in relation to growth stage, plant part and time of season
Authors: JEGER M. J. , JONES D. GARETH , GRIFFITHS ELLIS 
Published: February 2008

SUMMARYSporulation of Septoria nodorum was assessed on inoculated spring wheat cvs Kolibri and Maris Butler. The time from inoculation to first production of spores (latent period) was similar over a range of constant temperatures (12–18°C) but was shorter for Kolibri at 6°C and at 24°C. Spore production was greatest during the period of stem extension and, for equal amounts of disease, was twice as great on Kolibri as on Maris Butler. Spore production on leaves was much more intense with Septoria tritici than S. nodorum for equal amounts of disease, and was less intense on heads than on leaves for both pathogens. Inoculation of plants resulted in significant losses in yield. Mans Butler consistently out‐performed Kolibri on each component of yield. Kolibri was particular affected: 1000‐grain weights were reduced at each growth stage tested especially by S. nodorum, grain numbers and yield/head were reduced particularly following inoculation at heading. Spore production of S. nodorum during the period of stem extension increased to a peak in early July and then declined but no reliable relationship with monitored weather accounted for this seasonal trend.
Fungicidal control of Macrophomina phaseolina altered in pathogenicity by substrate nutrients
Authors: HOODA INDRA , GROVER R. K. 
Published: February 2008

SUMMARYThe presence of different carbon and nitrogen sources and bivalent metal compounds in the substrate medium influenced the mycelial growth of Macrophomina phaseolina and in vitro susceptibility to fungicides. The inoculum from such substrate media showed differences in pathogenicity on mung bean (Vigna radiata). Sucrose and asparagine significantly increased the mycelial growth as well as pathogenicity of the fungus. Absence of bivalent metal ions, viz., Fe++, Zn++ and Mg++ in the medium produced inoculum which caused maximum seedling mortality and foliage blight.Carbendazim and thiophanate‐M as seed treatments were significantly less effective when the inoculum was from a medium containing glucose than when the inoculum was from a medium containing sucrose. Captafol and thiram gave significantly better disease control on mung bean when the inoculum used for soil inoculations was from media containing asparagine and ammonium nitrate compared to the inoculum grown on a medium containing sodium nitrate. Carbendazim, thiophanate‐M, PMA, captafol and thiram gave good disease control when the inoculum used was raised on a medium devoid of bivalent metal ions. Carbendazim and thiophanate‐M were the best fungicides as foliar treatments and controlled the disease irrespective of carbon, nitrogen and bivalent metal ion status of the substrate medium used for the production of inoculum.
The relationship between numbers of Heterodera schachtii and sugar beet yields on a mineral soil, 1978‐81
Authors: COOKE D. A. 
Published: February 2008

SUMMARYIn a 4‐yr field experiment on a mineral soil infested with beet cyst nematode (Heterodera schachtii) the relationship between root yield of sugar beet (y) and initial population of H. schachtii (Pi) fitted the equation: y=y min +(y max ‐ y min) ZPi‐T y min = 7·7 t/ha, y max = 39·4 t/ha, 2 = 0·99938 and T= 0 eggs/100 g soil. From this information and that obtained during a recent survey of 2766 beet fields, the total national root yield loss caused by H. schachtii was estimated as approximately 10 000 t/annum on mineral soils and (assuming a similar yield loss relationship on all soil types) 30 000 t/annum on organic soils.No consistent differences in efficiency of extracting cysts were found between the Fenwick Can and the flotation column. A bioassay technique was as effective as cyst extraction techniques in identifying infested soils.
The tolerance of difenzoquat and diclofop‐methyl by winter wheat varieties at different growth stages
Authors: TOTTMAN D. R. , LUPTON F. G. H. , OLIVER R. H. 
Published: February 2008

SUMMARYWinter wheat varieties were treated with the wild‐oat herbicides difenzoquat and diclofop‐methyl at several growth stages in a series of four field experiments.High rates of difenzoquat damaged the winter wheat varieties Bouquet, Sportsman, Hobbit and Maris Huntsman but not Hustler. Treatment of the sensitive varieties during tillering stimulated excessive tiller production, resulting in more ears with fewer and smaller grains than on the unsprayed controls; later applications reduced the number of grains and severely depressed yield.In contrast, the early applications of diclofop‐methyl, during tillering, were more damaging than the later ones. Bouquet was more tolerant of diclofop‐methyl than were the other varieties tested.