bluuebunny/crossref_metadata_2025_split huggingface dataset:
Celery Mosaic Virus in England
Authors: Pemberton A. W. , Frost R. R. 
Published: April 2007

SUMMARYA virus has been isolated from celery crops in Lincolnshire, Cambridgeshire, and Norfolk, from eight different cultivars on 15 of 18 farms sampled, but has not been found in any cultivars on 10 farms in Lancashire. It has also been isolated from hemlock on three farms in Cambridgeshire. The incidence of infection has varied considerably with an average level of about 15 per cent but 90 per cent crop infections have been observed.The virus causes most prominent symptoms in cvs. Lathom Blanching and Fenlander, causing a slight stunting of the former and a more serious reduction in growth of the latter. It is aphid‐transmitted in a non‐persistent manner. The virus has flexuous rod‐shaped particles approximately 780 nm in length, and is apparently restricted in its host range to the Umbelliferae. Its relationship to Western celery mosaic virus */*: */*: E/E: S/Ap is discussed.
A Field Survey of Watermark Disease of Cricket Bat Willow in Essex and Observations on Some of the Probable Sources of the Disease
Authors: Wong W. C. , Nash T. H. , Preece T. F. 
Published: April 2007

SUMMARYThe geographical distribution of trees of cricket bat willow (Salix alba var. caerulea) showing watermark symptoms of infection by Erwinia salicis (Day) Chester during 1955 to 1972 is recorded. In an attempt to control the disease by eradication, 23,172 trees were destroyed in this 18‐year period, as were 911 mother trees (stools) producing propagating material. During an intensive survey in 1972, 301 trees and seven stools were found to be infected out of an estimated total crop of 400,000 trees. In that year, agglutination tests and culturing sap were used in addition to the examination of trees with symptoms other than watermarking in the wood. The field observations, together with some experimental inoculations, indicate that the main sources of the disease in the field each year probably are (1), the nearby stumps of felled diseased trees and (2) infected propagating material.
Sources of Potato Blight (Phytophthora infestans) in the East of Scotland
Authors: Boyd A. E. W. 
Published: April 2007

SUMMARYSince 1965, 146 early occurrences of blight on field crops were recorded in the East of Scotland before the end of July. Of these, 119 were investigated to determine the source of infection, and 78 were found to be associated with heaps of discarded potatoes on which Phytophthora infestans was actively sporulating.From samples of bright‐affected foliage taken from such dumps a wide range of races was detected.In 1971 and 1972, attempts were made to control growth on discard heaps throughout East Lothian, a county in South‐east Scotland relatively isolated with regard to spread of blight, to determine whether this would delay the onset of blight in this area. In 1971, blight was recorded first on 17 August whereas further north in the counties of Perth, Angus and Fife it was noted on 5 July. The same pattern obtained in the latter counties in 1972 but no field cases of blight were recorded in East Lothian during the whole season. However, neither season was a ‘blight year’.The lack of sources on potato dumps may have contributed to this delay, or even absence, of blight but other factors may well have had more influence. In the counties where blight occurred early i.e., in July, there was a highly significantly greater total acreage of potatoes, and also the proportion of this acreage devoted to the tuber‐susceptible cultivar King Edward was very highly correlated with the incidence of early reports. The influence of such a cultivar was illustrated by the fact that 45 per cent of the outbreaks of blight recorded up to the end of July related to King Edward.
Susceptibilities of Carrot Cultivars to Carrot Fly (Psila rosae (F.)
Authors: Hill D. S. 
Published: April 2007

SUMMARYIn 1972 a trial on susceptibility to carrot fly infestation was conducted on peat soil in East Anglia using 17 carrot cultivars sown on two dates one month apart. The only insecticide applied to the carrots was an aphicidal spray. The early‐sown carrots were damaged by the first generation of larvae, but, by the second sampling date in October, there were no infestation differences between the two sowings. At harvest in December, significant differences in infestation levels occurred; these ranged from 82 per cent damaged roots for Amster‐dammer Bak, 87 and 88 for two stocks of Royal Chantenay, to 97 per cent for Danvers 126. It is not yet clear whether the differences can be profitably exploited as an adjunct to other methods for controlling this pest.
Preliminary Evaluation of Fungicides to Control Red Core of Strawberry
Authors: Montgomerie Isabel G. , Kennedy D. M. 
Published: April 2007

SUMMARYIn pot experiments, the fungicides captafol, chloraniformethan, dimethirimol, dinocap, dithianon, drazoxolon, folpet, miancozeb, mancozeb and zineb, terrazole, FUN 52.133, R 22395 and R 45173 decreased the per cent by number of strawberry roots infected by zoospores of Phytophthora fragariae. Only terrazole and R 22395 were more effective than Bayer 22555 which was used as a standard.
The Perennation and Control of Pear Scab (Venturia pirina Aderb.)
Authors: WILLIAMSON CYNTHIA J. , BURCHILL R. T. 
Published: April 2007

SUMMARYThe production of ascospores of Venturia pirina from overwintered infected leaves, and of conidia from stem lesions was assessed in 1969 and 1970. Autumn post‐harvest dips of infected leaves in phenylmercuiic chloride (0·01 per cent), benomyl (0·0125 per cent a.i.), thiabendazole (0·0125 per cent a.i.) and urea (5–3 per cent) prevented ascospore formation in the following spring. Spring pre‐bud‐burrst dips in these chemicals partially suppressed ascospore production., but conidia production from stem lesions in spring was stimulated by autumn, followed by pre‐bud‐burst, sprays of benomyl, urea and PMC.
Lettace Root Aphid Control by Means of Plant Resistance
Authors: DUNN J. A. , KEMPTON D. P. H. 
Published: April 2007

SUMMARYAt Wellesbourne, Warwick, in 1968, not all plants of the lettuce cv. Webb's Wonderful protected against lettuce root aphid. Pemphigus bursarius (L.), by diazinon pre‐sowing treatments remained uncolonized throughout a relatively light aphid attack but no colonization of unprotected plants of cv. Avoncrisp occurred. In a second experiment in 1972, in which plants were untreated and exposed to an intense aphid attack, the lettuce cvs. Mildura, Borough Wonder, Webb's Wonderful, Avoncrisp and Avondefiance all attracted similar large numbers of winged root aphid rnigrants. No root colonies formed on the resistant CVS. Avoncrisp and Avondefiance. All plants of the other cultivars became severely damaged and most were killed.
The Effects of Benomyl on Sensitive and Tolerant Isolate of Botrytis cinerea infecting Strawberries
Authors: JORDAN V.W.L. , RICHMOND D. V. 
Published: April 2007

SUMMARYStrawberry plants cv. Cambridge Vigour growing in a walk‐through polyethylene tunnel were experimentally inoculated with one benomyl‐sensitive and two benomyl‐tolerant isolates of Botrytis cinerea alone and in combination.Three applications of benpmyl significantly increased the number of infected fruits in four out of the six treatments. There was no significant increase in infection on plants inoculated only with the benomyl‐sensitive isolate. Plants inoculated only with a slow growing, benomyl‐tolerant isolate showed an increase in infection which was not quite enough to be significant at the 5 per cent level.The fast growing benomyl‐tolerant isolate spread more rapidly from plot to plot than the slow growing isolate.
The Incidence of Ryegrass Mosaic Virus in Crops of Ryegrass grown for Seed in some Southern Counties of England
Authors: HEARD A. J. , BROOK B. A. , ROBERTS E. T. , COOK R. J. 
Published: April 2007

SUMMARYItalian ryegrass, cultivars Aberystwyth S22 and perennial ryegrass, CV.S321, grown for the production of seed in the A.D.A.S. S.E. Region and Wiltshire were surveyed for ryegrass mosaic virus (RMV). Visual leaf symptoms were used to assess infection; the diagnosis was checked using the electron microscope.RMV infection was widespread in both grasses and about 30 per cent of the fields carried an infection level greater than 10 per cent (based on number of plants infected/examined). Higher levels of infection were encountered in crops of Italian ryegrass than in perennial ryegrass. Out of 69 fields of Italian ryegrass, only 12 showed no infection whilst nine fields showed a level of infection greater than 30 per cent. Twenty‐eight of the 61 fields of perennial ryegrass showed no infection and the highest level of infection found was 26 per cent.All of the Italian and most of the perennial ryegrass crops were in their first harvest year. Since Italian ryegrass crops were occasionally encountered with more than 70 per cent of the plants infected, it is obvious that RMV can spread very quickly.In perennial ryegrass fields an increase in the amount of N fertilizer applied in the spring led to an increase in RMV; an increase from 100 to 200 kg N/ha led to an increase in the level of RMV from 9 to 37 per cent.By the first harvest year, fields sown in the spring of the previous year (usually under a cereal crop) were generally much more heavily infected than those sown in the autumn of the same year.
The Distribntion and Abondance ot Parasitaphelenchus oldkami, a Nematode Parasite of Scolytus scolytus and S. multistriatus, the Bark Beetle Vectors of Dutch Elm Disease
Authors: HUNT D. J. , HAGUE N. G. M. 
Published: April 2007

SUMMARYIn 1971 and 1972 populations of Scolytus scolytus (F.) in several counties in England were heavily parasitized by Parasitaphelenchus oldhami Rühm, but in S. multistriatus (Marsh.) P. oldhami was markedly less abundant. Infestation of S. scolytus was 54 per cent in 1971 and 61 per cent in 1972, while the mean number of parasites per infested beetle was 32 and 41 respectively. For S. multistriatus the comparable figures were 55 per cent in 1971 and 44 per cent in 1972 with means of 12 and 10 parasites per beetle. Despite the high levels of parasitism, no pathological effects on the beetles were observed.
Effects of Metopolophium dirhodum on Spring Wheat in the Glasshouse
Authors: LOWE H. J. B. 
Published: April 2007

SUMMARYPot‐grown plants of spring wheat, cultivar Maris Dove, Were subjected, commencing at ear emergence, to different, constant levelsof infestation hy Metopolophium dirhodum (Wlk.) in a glasshouse. Infestation with six aphids per stem over 11 days had no significant effect on yield. Infestations with either six or 50 adult aphids or their equivalents, when maintained until ripening, resulted in lower yields of both grain and straw dry matter. Loss of grain was due to reduction in both 1,000 grain weight and the average number of grains per fiertile spikelet. Harvested dry matter content of leaf blades was unaffected by infestation, but the dry matter, content of stems was reduced in infested plants. In breeding aphid‐resistant cereals for Britain, resistance characters restricting aphid multiplication are most likely to reduce yield losses due to aphid attack.
Fireblight in Hawthorn in England and Denmark
Authors: BILLING EVE , BECH‐ANDERSEN J. , LELLIOTT R. A. 
Published: April 2007

SUMMARYHawthorn is a common reservoir of the fireblight pathogen in England and Denmark. As in other hosts, the pathogen may overwinter in infected shoots, twigs and branches. Symptoms of canker, shoot and blossom infections are similar to those described for pear and apple. Eradication of fireblight in hawthorn is not a practical possibility in either country and alternative means for containing the disease are discussed.
Interactions between Varieties of Gaeumannomyces graminis and Phialophora radicicola on Roots, Stem Bases and Rhizomes of tbe Gramineae
Authors: DEACON W. 
Published: April 2007

SUMMARYInteractions between varieties of the take‐all fungus, Gaeumannomyces graminis (syn. Ophiobolus graminis) and of Phialophora radicicola on living hosts are considered. This follows the earlier recognition of both morphologically and ecologically different varieties of these fungi. Interactions occur between all combinations of these fungi tested, so the fungus common in British grasslands, P. radicicola var. graminicola, is not peculiar in being able to restrict colonization of roots by the take‐all fungus in unsterile soil. However, the outcome of these interactions (that is, both the direction in which and the intensity with which they occur) depends on (1) the relative inoculum levels of the fungi; (2) the host species or organ; it also depends on the relative inoculum potentials of the fungi. Thus, under suitable conditions the weakly and non‐pathogenic ones compete successfully with the pathogen, G. graminis var. tritici (wheat take‐all fungus) and so reduce disease levels. But this fungus, itself, can restrict growth of its potential competitors, which may explain why grass leys often carry‐over take‐all between cereal crops, because despite the known ability of P. radicicola var. graminicola on grass roots to compete with the pathogen, the pathogen population is at first much higher than that of P. radicicola var. graminicola.Possible explanations are offered as to why rhizomatous grasses commonly harbour the take‐all fungus in old pastures.Results of this and of previous work are discussed in relation to prospects for biological control of turf and cereal diseases caused by varieties of G. graminis and similar fungi, like Leptoshaeria narmari and L. korrae.
Notes on the Biology of Carrot Fly in Eastern England
Authors: COPPOCK L. J. 
Published: April 2007

SUMMARYObservations on the biology of carrot fly (Psila rosae (F.)) were made in the important carrot‐growing areas of eastern England in the period 1948–72.Adults of the spring generation usually emerged in May and peak numbers were usually swept during the third and fourth weeks of May. Eggs were found from the end of May and larval damage was evident from late June. Calculations of accumulated day‐degrees of air temperature above 42°F (5.6°C) showed that peak emergence could generally be associated with a total of 422 day‐degrees commencing on 1 April. Both separate and combined totals of accumulated day‐degrees for February and March were markedly different in years of early and late fly emergence. Adults of the second generation appeared from late July onwards and oviposition occurred mainly during August and September, although in some years eggs were found much later. Resulting larval damage was present by October and increased in severity until the crop was harvested.
Aspects of Damage by Strawberry Ground Beetle (Pterostichus madidus (F.))
Authors: LUFF M. L. 
Published: April 2007

SUMMARYDamage to strawberries by strawberry ground beetle (Pterostichus madidus (F.)) was studied by laboratory experiments and observations in a walled garden in south Northumberland during 1969 and 1970. Beetles preferred ripe to unripe fruit, eating holes mainly at the widrat part of the fruit. A beetle density of 4.2 per m‐ thrioughout the fruiting season resulted in a peak of 13 per cent of the fruit being damaged, with up to four holes per fruit. Both starvation and desiccation increased the beetles capacity for strawberry feeding, although hunger had more effect than thirst.
Laboratory Observations on tbe Effect of Soil Compaction on Slug Damage to Winter Wheat
Authors: STEPHENSON J. W. 
Published: April 2007

SUMMARYWhen the aggregates of fairly dry, medium‐coarse soil were broken down and firmed over the seed by moderate or heavy pressure, slug damage was reduced. Coarse soil aggregates did not break down so well, particularly under heavy pressure; many seeds remained exposed and were damaged. The seed was also protected by deep planting, with the penalty of late emergence of the seedlings.
Assessment of Loss caused by Barley Mildew using Single Tillers
Authors: RICHARDSON M. J. , JACKS MARGARET , SMITH SUSAN 
Published: April 2007

SUMMARYA method for estimating losses due to foliar diseases with more precision, using little space and time and without the need for artificially producing different levels of disease, is described. Randomly selected tillers were labelled with their mildew level on leaf 2 at growth stage 10.5 and the ripe ears harvested to obtain values for seed number, seed weight and yield for each ear. Regressions of all three parameters on mildew level were negative and highly significant. Converted to per cent loss equations the mean regression coefficients for cvs. Ymer and Golden Promise were:—seed weight on mildew, 0·257; seed number on mildew, 0·291; and yield/ear on mildew, 0·498. There was no evidence of non‐linearity in the response of yield loss to mildew.
Resistance to Binapacryl in Field Populations of Fruit Tree Red Spider Mite, Panonychus ulmi (Koch)
Authors: CRANHAM J.E. 
Published: April 2007

SUMMARYAssays in 1969 on larvae of Panonychus ulmi from English apple, orchards showed an average 4x resistance to binapacryl after three to five years' use and, except for one population, a low degree of cross‐ resistance to dinocap. In contrast, there was no resistance to dinocap after four to ten years' use of this material. A resistant strain, after prolonged selection with binapacryl in the laboratory, showed 16x resistance to binapacryl and 2x cross‐resistance to dinocap in assays on adult female mites.
Specific Feeding Preferences of Tortricid Larvae on Flowering Strawberry Plants
Authors: ALFORD D. V. 
Published: April 2007

SUMMARYExamination of the feeding preferences of tortricid larvae attacking strawberry plants in eastern England during the main pre‐harvest blossom periods of 1972 and 1973 indicated that most larvae (85–6 per cent) of Acleris comariana (Lienig & Zell.) fed on foliage rather than on flowers or developing jfruitlets. However, this was not true for Clepsis spectrana (Treits.) (87–7 per cent on flowers), Olethreutes lacunana (Denis & Schiif.) (77–6 per cent on flowers) and Cnephasia interjectana (Haw.) (98–5 per cent on flowers). At densities of up to 12–5/m2, larvae of A. comariana had no observable effect on strawberry yields. Neither fruit quality nor quantity was correlated with pest (larval) numbers. The possible economic importance of A. comariana is considered in the light of these results and in comparison with published data for more directly damaging tortrix species. The role of the parasite Litomastix aretas (Wlk.) in controlling A. comariarm populations in East Anglia is also discussed.
The Effect of Phorate, a Wide‐spectrum Pesticide, on the Occurrence of Spraing in Twelve Cultivars of Potato
Authors: SYKES G. B. 
Published: April 2007

SUMMARYDuring 1973 the susceptibility to spraing of 12 commercial potato cultivars was tested on land in North. Worcestershire infested with viruliferous Trichadorus nematodes.The wide‐spectrum pesticide phorate reduced spraing in the harvested crop by over 60 per cent compared with untreated plots, bat the order of symptom expression was similar in both treated and untreated plots.
The Effect of Heat on the Hatch of Potato Cyst Eelworms
Authors: STONE L. E. W. , WESLEY D. P. 
Published: April 2007

SUMMARYThe effect of heat on potato cyst eelworm cysts, Heterodera pallida Stone (British pathotype E) and H. rostochiensis Woll. (British pathotype A) was investigated in the laboratory in 1967–69.Hatching from wet cysts of H. pallida was completely inhibited after 4 minutes’ exposure to 50°C and above. Air‐dry cysts were more resistant to heat; hatching was only prevented at 90°C.Results indicate that H. pallida is more susceptible to heat than H. rostochiensis.
Soil Placement of Insecticide Granules for the Control of Cabbage Root Fly on Transplanted Canliflowers
Authors: BEVAN W. J. , KELLY I. R. 
Published: April 2007

SUMMARYSeven organophosphorus insecticides were evaluated as granular formulations for the control of cabbage root fly, Erioischia brassicae (Bouche), in west Yorkshire, on transplanted cauliflowers from 1966 to 1970 inclusive. The insecticides were chlorfenvinphos, diazinon, dimethoate, fonofos, mecarbam, pirimiphos‐ethyl and thionazin. Various methods of application were compared and the work evolved into a comparison of the effectiveness of continuous bands of granules applied below the surface immediately before plant insertion with that of surface bands applied immediately after plant insertion. The methods employed and the equipment involved are described.Chlorfenvinphos was the most effective chemical for protecting the roots from cabbage root fly attack. Diazinon, dimethoate, fonofos, mecarbam and thionazin all reduced damage in the early part of the season (except when applied by the bow‐wave method). The subsurface method of placement of all these chemicals except dimethoate was consistently more effective in reducing root damage and promoting higher yields than surface placement. Pirimiphos‐ethyl was not effective in protecting the roots by either method.
Attempts at Cultural Control of Carrot Fly Damage to Carrots in East Anglia
Authors: COPPOCK L. J. , MASKELL F. E. , GAIR R. 
Published: April 2007

SUMMARYAt sites in Norfolk in 1970, 1971 and 1972, growing carrots were covered in situ with soil or straw for varying periods in attempts to prevent egg laying and subsequent late‐season damage by larvae of the carrot fly (Psila rosae) (F.))‐ Neither soil nor straw was sufficiently effective in this respect. Carrots chemically defoliated and/or covered during the main egg‐laying period in August and September were adversely affected in size and quality.
The Role of Mites in the Transmission of Smoulder in Narcissus
Authors: GRAY E. G. , SHAW M. W. , SHIEL R. S. 
Published: April 2007

SUMMARYInfection by Sclerotinia narcissicola Greg, was observed in narcissus bulbs during autumn, in leaf initials colonized by bulb scale mites (Steneotarsonemus laticeps (Halb.)), and on lesions of varying extent on the corresponding tissue after emergence.Presence or absence of smoulder sclerotia on outer scales of bulbs was not related to the incidence of infection of shoots.There was no evidence that smoulder was reduced by treatment for control of bulb mites (Rhizoglyphus echinopus (Fum. & Rob.)).
Preliminary Field Plot Trials on Biological Control of Sclerotinia trifoliorum by Coniothyrium minitans
Authors: TURNER G. J. , TRIBE H. T. 
Published: April 2007

SUMMARYLaboratory‐cultured sclerotia of Sclerotinia trifoliorum were placed in retrievable nylon bags on the surface of initially bare field plots and treated with three levels of a pycnidial dust preparation of the parasitic fungus Coniothyrium minitans. Four trials were set up, two beginning in July 1972 and two on 28 February 1973; each ran for 12 weeks. After that period in the first July trial, 37, 53 and 65 per cent destructive infection of sclerotia and 88, 93 and 98 per cent total infection of sclerotia (destructive and slight infection) occurred at the increasing levels of applied inoculum. In the second July trial there was much less infection, attributed to less weed growth in the plots and consequent lower surface moisture. Both the early spring trials resulted in appreciable infection of sclerotia. This was less than in the first July trial but greater than in the second, and was interpreted to be a result of a combination of lower temperatures and satisfactory moisture conditions.
A Comparison of Two Methods of Overall Fumigation for the Control of Docking Disorder of Sugar Beet
Authors: COOKE D. A. , HOLDEN M. R. 
Published: April 2007

SUMMARYField experiments in Norfolk in 1969–70 and in Yorkshire and Norfolk in 1970–71 and 1971–72 compared the control of Trichodorus spp. and Longidorus spp. given by different rates of dichloropropene placed by a tine injector and by a sub‐surface sprayer. Increasing rates of fumigant up to 410 1./ha improved nematode control; populations recovered only slightly a year later. The larger rates of fumigant increased sugar yield especially when the crop had shown Docking disorder symptoms, but there was no consistent difference between the two methods of application in controlling nematodes or increasing sugar yield.