bluuebunny/crossref_metadata_2025 huggingface dataset:
Further Observations on the Resistance of Chrysanthemum Cultivars to White Rust (Puccinia horiana Henn.)
Authors: Dickens J. S. W.
Published: April 2007

Infection experiments on a number of cultivars of the florists' chrysanthemum, with white rust from a recent outbreak in south‐east England, indicate the existence of more than one physiologic race of this fungus.
Dieldrin‐resistant Onion Fly (Delia antiqua (Meig.)) in England
Authors: Gostick K. G. , Powell D. F. , Slough Christine
Published: April 2007

Dieldrin was applied topically, in microdrops of 2‐ethoxy‐ethanol, to adult onion flies from a laboratory‐bred susceptible strain and six field populations suspected of being resistant. Dieldrin resistance was confirmed in onion flies from Bedfordshire and Norfolk in 1969.
Comparison of a Copper and a Mercury Spray Programme Against Apple Canker (Nectria galligena Bres.)
Authors: Bennett Margery
Published: April 2007

An autumn and spring spray programme of copper (as a proprietary wettable Bordeaux) was compared with a similar programme with an organomercury (PMC) fungicide for the control of apple canker caused by Nectria galligena in three successive years. Inoculum was provided prior to the spray applications and no cankers were removed during the trial. Fewer cankers developed on the trees receiving mercury sprays than on those sprayed with copper in each of the three seasons 1968 to 1970. However, spore counts made from rain run‐off revealed a relatively higher inoculum on the mercury sprayed trees, which might constitute a hazard when the protective effect of the sprays ceased.
Observations on the Biology and Control of the Plum Fruit Moth
Authors: Vernon J. D. R.
Published: April 2007

Observations on the biology of the plum fruit moth, Laspeyresia funebrana (Treits.), in an orchard near Cambridge, England in 1967 showed that only one main generation occurred, with a partial second generation in late summer. Eggs of the first generation were laid between 16 June and 8 August, with between one and nine eggs per fruit. Seventy‐five per cent of the eggs were laid on the basal half of the fruit. There was no evidence of egg parasitism, but Apanteles sp. was bred from one larva. Egg mortality was negligible, but larval mortality (on cv. Wyedale) was high (68 per cent), caused partly by the failure of first larvae to establish themselves in the fruit. Once established, competition between larvae resulted in further mortality. Three sprays of azinphos‐methyl gave 100 per cent control of larvae.
Effect of Eyespot (Cercosporella herpotrichoides) and Seed Treatments of Benomyl, Chlormequat and Organomercury on Rye
Authors: Rawlinson C. J. , Davies J. M. L.
Published: April 2007

A field trial of autumn‐sown rye cv. Lovaszpatonai subject to natural infection with Cercosporella herpotrichoides showed that eyespot, in the absence of lodging, was significantly correlated with reduced grain size and 1,000 grain weight but not with total yield in weight of grain. No seed treatment affected total yield although benomyl significantly increased fertile tiller number, increased the percentage of lesion‐free tillers in April, and by July, compared with the control, had reduced the number with eyespot lesions by 38 per cent. In laboratory experiments organomercury and a combined treatment of organomercury plus chlormequat protected seedlings from attack by seedborne fungi and in the field trial these treatments also increased the percentage of lesion‐free tillers in April but did not affect the numbers with eyespot in July.
Observations on the Development of the Brassica Cyst Eelworm
Authors: Lewis Serfiah
Published: April 2007

In South Wales two generations of brassica cyst eelworm (Heterodera cruciferae Franklin) can be completed in a year and development of a third generation proceeds slowly over winter. No consistent increase in cyst populations occurred in two fields sampled annually for eight years and two sampled annually for five years.
A Method of Screening Strawberries for Resistance to Verticillium Wilt
Authors: Jordan V. W. L.
Published: April 2007

A technique is described for rapid testing of strawberry plants for resistance to verticillium wilt. Plants were inoculated by dipping roots in a conidial suspension (100,000/ml) of the pathogen and replanting them in a light sandy soil containing Verticillium‐infected plant debris. With soil temperature maintained at 20°C, air temperature above 18°C and 14 hr of supplemented light, conditions favoured infection and symptom production. Reproducible results were obtained with standard cultivars of known field performance.
Synonymy as a Source of Confusion in Distinguishing between certain Tineid Lepidoptera
Authors: Alford D. V.
Published: April 2007

As a result of nomenclatorial changes both the cocksfoot moth (Glyphipterix simpliciella (Steph.)) and the diamond‐back moth (Plutella xylostella (L.)) are liable to be confused with other tineid species. To avoid this confusion, some details and illustrations are given of the species concerned.
Comparison of Some New Fungicides for the Control of Scab and Powdery Mildew of Apple
Authors: Burchill R. T. , Williamson Cynthia J.
Published: April 2007

In 1969, apple scab was controlled equally well by spraying at 14 or 28 day intervals with benomyl (0.025 per cent a.i.). Triarimol (0.004 per cent a.i.) at 14‐day intervals was even more effective and also surpassed benomyl in controlling apple mildew.

In 1970, when the dry summer prevented apple scab development, triarimol apphed at 10‐day intervals again provided the best control of apple mildew. Sprays of thiophanate (NF 35) (0.05 per cent a.i.) and thiophanate‐methyl (NF 44) (0.05 per cent a.i.) applied at 10‐day intervals were no better than the standard captan/dinocap programme, but triarimol and benomyl at 21‐day intervals were less effective.
Observations on the Biology and Control of Stem Eelworm (Ditylenchus dipsaci (Kühn) Filipjev) on Hydrangea (Hydrangea macrophylla Ser.)
Authors: French N. , John M. E. , Williams J. J. W.
Published: April 2007

The life cycle of Ditylenchus dipsaci in hydrangea is similar to that in other plants: eggs hatched in about eight days and adults developed in 12 days at 19°C. The eelworms infesting hydrangea were shown to be of an oat‐onion race. Hot‐water treatment killed the plants before achieving complete control. Thionazin soil drenches at 0.02 per cent and 0.03 per cent gave good control of eelworm but 0.005 per cent and 0.01 per cent failed to give satisfactory control in some experiments. The higher rates caused some phytotoxicity particularly to rooted cuttings and forced plants. Thionazin 10 per cent granules at 2 oz per bushel (56.7 g per 36.4 1.) of compost caused very severe phytotoxicity.
Glasshouse Fumigation with Formaldehyde
Authors: White J. G. , Fletcher J. T.
Published: April 2007

Fumigation for 1 hr in a 50 cu. ft (1.42 cu. m) chamber with a rate eqmvalent to 0.75 lb potassium permanganate/3 pt formaldehyde/ 6,000 cu. ft (0.34 kg/1.70 1./169.90 cu. m) killed spores of Botrytis cinerea, Fulvia fulva and Fusarium culmorum, though in a series of 1 hr fumigations based on this rate the mycelium of B. cinerea was not killed. Fumigations for 24 hr in a 50 cu. ft (1.42 cu. m) chamber and a commercial glasshouse with 0.75 lb potassium permanganate/3 pt formaldehyde/6,000 cu. ft (0.34 kg/1.70 1./169.90 cu. m) and 0.8 lb/ 1.25pt/6,000cu. ft (0.36 kg/0.71 1./169–90 cu. m) killed both spores and mycelium of B. cinerea.
The Separation of Eggs of Erioischia brassicae and E. floralis in Swede Crops
Authors: SHAW M. W.
Published: April 2007

Eggs collected from around the base of cultivated cruciferous crops in north‐east Scotland were hatched on suitable media contained in petri dishes, or on plants grown in pots in an outdoor insectary. Breeding in petri dishes was more successful.

It was found that Erioischia brassicae(Bouche), the cabbage root fly, and E. floralis(Fall.), the turnip root fly, occur together in swede crops, but only E. brassicae in crops of cabbage and cauliflower. Despite the eggs of both species overlapping in size and the chorion patterns being indistingtiishable, plotting mean egg sizes over short consecutive periods showed that the main egg‐laying period of E. floralis was during August and September.

The measurements of eggs collected before and after 1 August, when plotted on arithmetical probability paper, indicated an appreciable difference in the average size of eggs laid in the two periods, but only at those sites where both species were found.
A Survey of Leaf Diseases of Spring Barley in South‐west England
Authors: Melville S. C. , Lanham Carol A.
Published: April 2007

The incidence of leaf diseases was assessed in approximately 150 crops of spring barley in Cornwall, Devon and Dorset in 1967–69 inclusive. Estimates of the percentage area of the laminae of the two top leaves affected by each disease were inade at growth stage 11.1 (Feekes scale). Mildew, leaf blotch and brown rust were the main diseases, mildew being the most severe in two of the years. Disease incidence varied with location and cultivar. Leaf blotch was usually more severe in earlier than in later sowings but the effect of sowing date on mildew severity was not consistent. None of the diseases was significantly more severe in crops which immediately followed barley than in those which did not, but the level of mildew was significantly lower after barley than after other crops. Thousand‐grain weight determinations, made on samples from a proportion of the crops surveyed, correlated well with the amount of total disease on the top leaf. The estimated loss in grain yield from all diseases ranged from about 19 to 22 per cent over the three years. Leaf blotch was more severe and mildew less severe in the three south‐western counties than in England and Wales as a whole.
An Effect of Cultural Practice on Populations of Clepsis spectrana (Treits.) (Lep., Tortricidae) on Black Currant
Authors: Dicker G. H. L.
Published: April 2007

An area of black currants in Kent, which had been cut for mechanical harvesting in July 1970, was observed in the following spring to be uniformly infested with larvae of Clepsis spectrana, whilst adjacent bushes which had been hand picked were practically free from larvae. This difference was attributed to adults preferring the post‐harvest growth, which occurred only on mechanically harvested bushes, as a site for oviposition.
Comparison of the Distributions of the Pink and the Green Biotypes of the Potato Aphid, Macrosiphum euphorbiae (Thos.), on Potato Plants
Authors: Wightman J. A. , Gibson R. W.
Published: April 2007

Field trials were condueted in 1967 and 1969 in south‐west England to compare the distributions on potato plants of green and pink biotypes of Macrosiphum euphorbiae. In both trials, the green biotype was most abundant on the lower, older leaves, whereas the pink biotype was of similar abundanee on all leaves irrespective of their position on the plant. Furthermore, the numerical predominence of the green biotype was greater on older plants.
Field Trials for the Control of Slugs on Winter Wheat
Authors: Gould H. J. , Webley D.
Published: April 2007

In a series of field trials during 1968–1970, 4 per cent methiocarb or 3 per cent metaldehyde baits, applied to plots before drilling winter wheat, effectively reduced the numbers of slugs found by various methods of trapping after treatment. In the dry conditions prevailing at most of the sites, there were few consistent differences between methiocarb and metaldehyde. Little grain damage occurred on the control plots at any of the sites as weather conditions after drilling did not favour slug activity. Small increases in plant stand were obtained on the treated plots but differences between treatments were not significant.
Chemical Control of the Strawherry Mite on Mown and Unmown Strawherry Plants
Authors: Alford D. V.
Published: April 2007

Both in experimental plots and on a field scale in East Anglia better control of Tarsonemus fragariae Zimm. was achieved by application of endosulfan when strawberry plants (cv. Cambridge Favourite) had previously been mown off after harvest. Therefore, where this pest is a problem removal of foliage before spraying should prove beneficial.
Chemical Control of Red Spider Mite on Glasshouse Roses
Authors: French N. , Ludlam F. A. B.
Published: April 2007

On a commercial nursery in east Kent where red spider mite (Tetrany‐ chus urticae(Koch)) showed resistance to demeton‐S‐methyl, dicofol and quinomethionate, alternative control chemicals were investigated during 1968 and 1969.

Chlorphenamidine, dinobuton, formetanate, methomyl, “Pentac” and chlorphenamidine plus formetanate all gave good control of the mite. Tetradifon gave good control in 1968 but not in 1969. Aldicarb proved ineffective in the one experiment in 1968, but good and persistent control was obtained in two of the three experiments in 1969. Binapacryl, fenazaflor, GS19851 and “Torak” did not significantly decrease mite numbers.

On a nursery in west Sussex, dinobuton, endosulfan, formetanate and quinomethionate applied in February 1971 to unpruned rose bushes, heavily infested with red spider mite, all gave good control of mites and eggs.
Host Plants of Tulip Stem Eelworm (Ditylenchus dipsaci)
Authors: HESLING J. J.
Published: April 2007

Cultivars of 15 species of crop plants were tested to find out if they were hosts of Ditylenchus dipsaci(Kühn) Filipjev from tulip. Some eelworms were recovered from all plants after eight weeks. Eelworms increased greatly in beans (Vicia and Phaseolus), peas (Pisum), onion (Allium cepa), turnip (Brassica campestris) and cucurbits, often without inducing plant symptoms.
Injury to Field Beans (Viciafaba L.) by Tylenchorhynchus dubius
Authors: Whitehead A. G. , Fraser Janet E.
Published: April 2007

Pots of sterilized soil were inoculated with a few Tylenchorhynchus dubius(Biitschli) and barley was grown twice in the pots. Although the barley was apparently not harmed, T. dubius multiplied greatly. Beans (Vicia faba L. cv. Tarvin) were then grown in the pots and were severely damaged by the nematodes. The method used could be adapted to suit other nematodes and crop plants.
Verticillium Wilt of Pelargoniums
Authors: Fletcher J. T. , Griffin M. J.
Published: April 2007

Verticillium wilt of Pelargonium x domesticum caused by Verticillium albo‐atrum and Verticillium dahliae is recorded in the U.K. Naturally‐infected plants showed severe symptoms during the summer but there was some recovery in the autumn and winter. In experiments, symptom severity increased at high temperatures but was not markedly in fluenced by day‐length treatments. Isolates of V. dahliae from chrysanthemum and pelargonium readily infected either host. Benomyl drenches at 1·5 g/4·5 1. at the rate of 200 ml/plant suppressed symptom expression and resulted in a high proportion of healthy cuttings from infected stock plants.
Observations on the Control of Tetmnychus urticae on Roses by Phytoseiulus persimilis
Authors: Simmonds S. P.
Published: April 2007

Observations at a holding in south‐west England in 1970 and 1971 have shown that the mite predator Phytoseiulus persimilis Athias‐Henriot can effectively control red spider mite, Tetranychus urticae (Koch), on roses under glass where the grower is willing to dispense with sulphur fumigation.
Some Properties of a Mechanically Transmissible Virus Widespread in Raspberry (Rubus idaeus) in Scotland
Authors: Jones A. T. , Murant A. F.
Published: April 2007

A virus, code‐named 52V, was obtained from 16 cultivars and seedlings of red raspberry by inoculation of sap to Chenopodium quinoa during spring or autumn. Some raspberry plants were infected with 52V after six months in the field, and more than 50 per cent of the plants of some cultivars were infected after four years. The virus was also obtained from Rubus occidentalis plants previously infected with virus from red raspberry by means of aphids (Amphorophora rubi and Aulacorthum solani). These aphids transmitted 52V from red raspberry to C. quinoa.

52V was transmitted by inoculation of sap to six herbaceous species but induced symptoms only in Chenopodiaceae. In C. quinoa sap, 52V lost infectivity after dilution to 10−2, heating for 10 min at 52·5°C, storage at 18°C for 24 hr or treatment with n‐butanol to 8·5 per cent (v/v). Preparations made by clarifying extracts with chloroform or ether followed by differential centrifugation contained a few isometric particles c. 30 nm in diameter which may be those of the virus.
Chemical Control of Red Spider Mite on Pot Chrysanthemums
Authors: Ludlam F. A. B. , French N.
Published: April 2007

Treatment of chrysanthemum cuttings, by dipping before planting or by spraying three weeks after planting, with diluted dicofol, Du Pont 1642, fenazaflor, formetanate,‘Pentac’ or quinomethionate reduced infestations of red spider mite (Tetranychus urticae (Koch)) nine weeks after planting. Dicofol, Du Pont 1642, formetanate, quinomethionate or tetradifon applied just before flowering gave good control of mites, and dicofol, formetanate, quinomethionate and tetradifon gave almost complete kill of eggs. Fenazaflor, particularly as a dip, caused phytotoxicity.
Shaggy Stipe, a New Disease of Cultivated Mushroom caused Mortierella bainieri
Authors: Fletcher J. T.
Published: April 2007

Symptoms are described of a new disease of mushrooms caused by Mortierella bainieri. Peeling of the stipe to give a shaggy appearance is one of the most characteristic symptoms. Similar symptoms were reproduced in an infection experiment. M. bainieri is less sensitive to benomyl than some of the other more common fungal pathogens of this crop.
Irrigation as a Practical Means to Control Potato Common Scab (Streptomyces scabies): Final Experiment and Conclusions
Authors: Lapwood D. H. , Wellings L. W. , Hawkins J. H.
Published: April 2007

In 1971, irrigation at Gleadthorpe E.H.F. had little or no effect on yields but, when applied early in the season, greatly decreased common scab on the susceptible cultivars King Edward, Majestic and Désirée. Record, and especially Pentland Crown, had little scab with or without irrigation.

Most‐scab infection occurred during dry weather in late June and early July. Irrigation for 6 wk from 4 June, at 0.6 in. (15 mm) soil moisture deficit (S.M.D.) controlled scab most effectively, but 6 wk was only marginally better than 4 wk. With other regimes, the severity of scab increased as the S.M.D. allowed before irrigation was increased. King Edward tubers from unirrigated plots were blemished more in 1971 than in the two previous dry seasons, partly because rain caused tubers to swell more than previously and enlarged scab lesions so much that healthy tissue between scabs was ruptured.

More tubers per plant were formed from King Edward when seed tubers were treated with benomyl and oxycarboxin before planting than when untreated, but irrigation even from 75 per cent emergence had no effect on tuber numbers.
Insecticidal Control of the Cabbage Leaf Miner, Phytomyza rufipes Meig., attacking Calabrese
Authors: Coaker T. H.
Published: April 2007

Damage caused by larvae of Phytomyza rufipes to the ‘spears’ of calabrese can reduce the quality of crops grown for processing. During 1969–71 inclusive, over 80 per cent of the plants in crops grown for a once‐off harvest were attacked by the miner. Eggs are laid on all the main‐stem leaves, but preference for the second to fourth leaves as oviposition sites caused peak attacks to occur at this stage of growth in the crops.

Weekly sprays of 0·1 per cent active ingredient of azinphos‐methyl, dimethoate or trichlorphon applied over the full six‐week period of attack reduced the damage by about 90 per cent, compared with a 70 per cent reduction when trichlorphon was applied over the period of peak attack.
NEPO Viruses in Raspberries in the West Midlands
Authors: Dale W. T. , Brown E. B.
Published: April 2007

Arabis mosaic virus (AMV) was found in several West Midland raspberry crops of cv. Mailing Promise and in one of Mailing Exploit, associated with stunted patches and yellow mosaic patterns on the leaves. AMV was not found in Mailing Jewel, even when adjacent to affected Mailing Promise and showing similar deterioration, but strawberry latent ringspot virus (SLRV) was isolated from affected plants of the former cultivar at two sites. Xiphinema diversicaudatum, the nematode vector of both viruses, occurred in soil samples from affected fields and when cucumber plants were grown in soil from one of the proven SLRV sites they became infected. Similarly, the virus was demonstrated in soil from where cv. Mailing Jewel had failed and been grubbed the previous autumn.
A Stemphylium Leaf Blight of Tomato
Authors: Dickens J. S. W. , Evans S. G.
Published: April 2007

A severe leaf blight of tomato caused by Stemphylium botryosum Wallr. is reported, and the pathogenicity of the fungus was confirmed. This is believed to be the first record of this fungus attacking tomato foliage in England. Benomyl sprays and drenches had been applied to the affected crops. In experiments, various benomyl drenches and sprays did not control the disease and there was no evidence that it was encouraged by such treatments. No seedborne infection was detected.
Observations on the Effects of Insecticides on Glasshouse Whitefly (Trialeurodes vaporariorum (Westw.))
Authors: French N. , Ludlam F. A. B. , Wardlow L. R.
Published: April 2007

In trials on a commercial cucumber nursery in Kent in 1971, malathion high‐volume sprays gave good control of whitefly adults and young ‘scales’. Malathion applied at ultra‐low volume (‘Turbair’) or as an aerosol was less effective. Malathion dust controlled only adults. Nicotine and petroleum oil were ineffective.

In laboratory and glasshouse experiments in 1972, 16 chemicals as sprays, dips, drenches, smokes or fumigants were tested against each stage of a malathion‐susceptible and a malathion‐resistant whitefly population cultured on French beans. Adults and larval instars of the susceptible population were well controlled by sprays (adults) and dips (larvae) of organophosphorus insecticides, DDT, bioresmethrin and pyrethrum; but only thionazin, DDT, bioresmethrin and pyre‐thrum gave adequate control of the resistant population. Thionazin drenches were moderately effective against susceptible larvae but gave poor control of resistant larvae. Dichlorvos and naled fumigants and DDT/gamma‐BHC smoke controlled susceptible larvae but only DDT/gamma‐BHC smoke was effective against resistant larvae. Excepting dips of cartap and DDT, treatments had little effect upon eggs. Larvae became more difficult to kill as age increased; only bioresmethrin (0·02 and 0·04 per cent active ingredient) gave good control of pupae.
Infection of Lolium multifiorum with Rhynchosporium Species
Authors: Wilkins P.
Published: April 2007

Rhynchosporium orthosporum was isolated from Lolium multifiorum from breeders’ plots at Aberystwyth twice as often as R. secalis. R. orthosporum from Dactylis glomerata, L. multiflorum or L. perenne would infect only the host genus from which it was isolated. R. secalis from L. multiflorum would produce symptoms not only on L. perenne, but on Hordeum sativum as well. Significantly, this was of race U.K.1, the most common race on H. sativum. Of 20 genotypes of L. multifiorum cv. RvP, 17 ranked similarly for level of resistance to both pathogen species. However, the remaining three genotypes were resistant to one, but markedly susceptible to the other. Progeny of selected resistant genotypes were far more resistant than the original cultivar. This suggests that there are reasonable prospects for resistance breeding.
An External Ringspot of Potatoes
Authors: Richardson D. E.
Published: April 2007

A disease resembling corky ringspot of potato caused by tobacco rattle virus in parts of the United States was reported in Yorkshire. Here also the ringspot symptoms were closely associated with TRV, although varietal reactions did not always correspond. Likewise, varietal reactions did not always correspond with those caused by potato mop top virus. A condition similar to the canker type of internal rust spot was present in some tubers bearing ringspots.
Observations on the Use of Phytoseiulus persimilis Athias‐Henriot to Control Tetranychus mticae (Koch) on Tomatoes
Authors: Dixon G. M.
Published: April 2007

During 1971 in the North Riding of Yorkshire six different methods of introducing the predator Phytoseiulus persimilis to control red spider mite on glasshouse tomatoes were compared with two acaricidal treatments. Introducing red spider mite on to every tenth plant three days before placing the predator on the same plants was the most effective method of preventing red spider mite damage. The methods of assessing predator and red spider mite populations as well as red spider mite damage on tomatoes are described.
Effects of the Apple Mildew Spray Programme on the Control of Fruit Tree Red Spider Mite
Authors: Butt D. J. , Cranham J. E.
Published: April 2007

Betaomyl, diethyl phthalimidophosphonothionate (‘Dowco 199’) and triarimol were less effective than binapacryl or dinocap in suppressing fruit tree red spider mite, Panonychus ulmi (Koch), in post‐blossom trials in Kent of fungicides active against apple powdery mildew, Podosphaera leucotricha. Residual effects observed in 1970 indicated that the extension of 10‐day programmes in 1969 from 30 June to 31 July improved mite control, except with triarimol. The omission of any consecutive pair of dinocap applications between late May and late June, 1970, increased the number of mites present at the end of the season more than did later interruptions of the programme. This period in early summer, which covered the hatching of winter eggs, is known to be crucial in the control of mildew. Mite damage was most severe following the omission of dinocap in late May and early June.
Septoria nodorum as a Seed‐Borne Pathogen of Barley
Authors: Holmes S. J. I. , Colhoun J.
Published: April 2007

Septoria nodorum occurs as a seed‐borne pathogen of barley. When seed of cv. Zephyr inoculated with S. nodorum was sown in the glasshouse, symptoms were not observed on coleoptiles, but the pathogen was present internally in some of them and caused a reduction in the mean height of seedlings in dry soil.
Effects of Aldicarb and some other Nematicides on Growth of Sugar Beet in Heterodera schachtii‐infested Soil
Authors: Dunning R. A. , Winder G. H.
Published: April 2007

The vigour and yield of sugar beet grown on Heterodera schachtii‐infested soils, with organic matter contents of 14 to 68 per cent, were increased by aldicarb granules applied in the seed furrow in field trials in eastern England in 1968 to 1970. Sugar yields were smallest on the most heavily infested sites; yield increases on plots treated with aldicarb were greatest at doses ranging from 11 to 31 oz active ingredient/ acre (770–2,170 g/ha), but increases were not enough to ensure a satisfactory crop. Post‐crop numbers of cyst eelworm were not decreased by treatment. Other candidate nematicides ‐ chlorfenvinphos, diazinon, fensulfothion, methomyl, ‘Neosar’, oxamyl, pirimiphos‐methyl, ‘Prophos’, thionazin, RD 18502, C14421 and R17210‐had no beneficial effect and several, especially at higher doses, were phytotoxic.
Repellents, Synthetic Pyrethroids, and Organophosphorus Compounds as Seed Dresangs against Wheat Bulb Fly (Leptohylemyia coarctata (Fall.)
Authors: GRIFFITHS D. C. , JEFFS K. A. , SCOTT G. C. , MASKELL F. E. , MATHIAS P. L. , ROBERTS P. F.
Published: April 2007

New insecticides, some in novel formulations, and insect repellents were tested during 1968–71 as seed dressings to protect winter wheat against attack by wheat bulb fly larvae. Preliminary tests in the laboratory were followed by trials in fields in the Midlands and eastern England. The synthetic pyrethroid insecticide resmethrin at one per cent active ingredient to weight of seed significantly decreased attack by wheat bulb fly in one trial on a sandy clay loam but not on other soils or in other years. The best protection against attack in the field was given by the organophosphorus insecticides C8874 (O,O‐diethyl O‐2,5‐dichloro‐4‐iodophenyl thiophosphate) and C18244 (O‐ethyl‐O‐(2,5‐dichloro‐4‐iodophenyl) ethyl thiophosphohate). These compounds were more eflective than chlorfenvinphos used as a standard but are unlikely to be developed further in this country.

Using polyvinyl acetate formulations, much larger amounts of pyrethroids could be applied to the seeds without decreasing plant emergence, but insect control was not improved. Pre‐treatment with liquid paraffin,‘Lutanol M40’(polyvinyl methyl ether) or ‘Polyvis 200’(polybutene) improved adhesion of γ‐BHC powder to seed, but effects on plant emergence and on insect control need more testing. A uniform seed to seed distribution of liquid insecticide was obtained by dipping seeds in dilute emulsions of ethion, but these seeds germinated less well than seeds treated with a commercial powder formulation of the same insecticide.

Seed dressings of the insect repellents ‘Deet’(N,N‐diethyl m‐toluamide), MGK 11 (2,3:4,5‐bis(2‐butylene) tetrahydro‐2‐furaldehyde) or MGK 874 (2‐hydroxyethyl‐n‐octyl sulphide) failed to protect winter wheat from attack by wheat bulb fly in the field.
A Companson between the ODCB Technique and Heat Extraction of Soil Cores for Estimating Leatherjaket Populations
Authors: SHAW M. W. , BLASDALE P. , ALLAN R. M.
Published: April 2007

Two methods of sampling leathetjackets (larvae of Tipula spp.) were compared during the two winters of 1965–66 and 1966–67.in north‐east Scotland. The core method using dry heat extraction gave a signifi‐cantly higher estimate of population than the orthodichlorobenzene (ODCB) technique from October to February, particularli in 1965–66. A comparison over three years in general survey work gave few significant deferences, but 49 out of 64 lields sampled showed a larger population when estimated by coring.
A Comparison between a Laboratory Test and a Glasshouse Test for Detecting Pleospora bjoerlingii Infection on Garden Beet Seed
Authors: SHARP M. K.
Published: April 2007

A glasshouse method was used to assess the total hazard from P. bjoerlingii to six known infected beet seed samples, and the results were compared with laboratory tests on both pretreated and untreated seed using the method of Mangan (1971) The results showed that the use of untreated seed in the Mangan test gave a clearer indication of potential crop hazard than did the use of treated seed. The glasshouse method involved growing for 5 to 6 wk after sowing in molochite, which enables total recovery of unemerged seed.
Chemical Control of the Chrysanthemum Leaf Miner, Phytomyza syngenesiae (Hardy) (Diptera: Agromyzidae)
Authors: GURNEY BARBARA , HUSSEY N. W.
Published: April 2007

Sprays (0·1 per cent) of bromophos or dioxathion afforded complete protection against both feeding ptmctures and mines of Phytomyza syngenesiae and could be used with parasites and predators. Other effective chemicals were azinphosr‐methyl, bendiocarb, carbophenothion, cartap, dimethoate and pirimicarb.
The Development and Control of Carnation Rust (Uromyces dianthi)
Authors: HILL S. A.
Published: April 2007

Summary

Carnation rust continues to cause crop losses despite improved methods for control of the glasshouse environment which should enable the prevention of infection.

The rapid development of the disease in the crop beneath ventilators compared with that in areas of crop not subject to surface moisture was demonstrated, and at the same time the effect of fungicidal sprays was observed.

Dithiocarbamate sprays applied at weekly intervals prevented the build up of the disease and gave better control than fortnightly sprays of a systemic material oxycarboxin, or of tetrachloroisophthalonitdle. A single drench application of oxycarboxin gave no control of the disease.
The Distribation of Eggs of Acleris comariana (Lepidoptera: Tortriddae) on Strawberry Plants
Authors: ALFORD D. V. , DOCKERTY A.
Published: April 2007

Significantly more eggs of Acleris comariana (Lienig and Zeller) were laid on the lower than on the upper surface of strawberry leaves (cv. Cambridge Favourite); most were found on the proximal half of the leaflets. Eggs were only noted on leaf laminae; none was found on petioles, stipules or stolons. Eggs were located on plants of all sizes, from well‐established mother plants to young runners, but most frequently occurred on older plants and on inedium‐sized leaves.
Field Srudies of Powdery Mildew (Erysiphe crucifearum on Brussels Sprouts
Authors: DIXON G. R.
Published: April 2007

In Brussels sprouts, Erysiphe critciferarum was found to penetrate deeply into the bads as well as infect the leaves and stems. Differences in the susceptibility of cultivars was evident in the field, and resistant cultivars included Bintree, Fasko 48, Frigostar, Groeningse Late, Leda, Solid Line and Triumph. Some cultivars had high levels of infection on the buds and low levels on the leaves, and other cultivars vice versa. Passage of infected buds through a mechanical stripper did not remove all infected bud‐leaves, and with highly susceptible cultivars it would be necessary to hand trim the buds also. In cold weather powdery mildew caused additional blemishing of the sprout buds since the areas around mycelial colonies turned black. A key for assessing the percentage leaf area infected is described.
Fumigation of Field Beans against Ditylenchus dipsaci
Authors: POWELL D. F.
Published: April 2007

Field beans (Vicia faba) were fumigated with methyl bromide at 18°C to control stem eelworm (Ditylenchus dipsaci (Kühn) Filipjev). Dosages of up to 2,000 mg.hr/l. failed to kill all the eelworms in their most resistant condition and produced a small but significant decrease in the percentage of normally germinating seeds, while a dosage sufficient to give a complete kill of eelworms caused a substantial decrease in germination. Nevertheless, standard commercial treatment of 1,000 mg.hr/l. should give a good control under normal conditions.
Laboratory Observations on the Distribution ofAgriolimax reticulatus (Müll.) in Different Aggregate Fractions of Garden Loam
Authors: STEPHENSON J. W.
Published: April 2007

The choice of resting places in bare soil of both immature and mature slugs Was influenced by the size of the soil aggregates. A moderate to coarse soil was preferred and it is suggested that response to contact stimuli may be partly responsible for this behaviour. Soil composed of fine aggregates was preferred for egg‐laying sites.
The Effect of Ethirimol Seed Dressings on Yield of Spring Barley grown with Different Amounts of Nitrogen Fertilizer 1969–71
Authors: JENKYN J. F. , MOFFATT J. R.
Published: April 2007

Ethirimol seed dressings usually increased the yields of Zephyr and Sultan barley more than those of other cultivars less susceptible to mildew. However, Julia and Vada also responded well, especially in experiments where brown rust was common. Julia and Vada have some resistance to foliage diseases other than mildew and this may affect their apparent response to fungicides applied to control mildew. Different amounts of nitrogen fertilizer affected the benefit from ethirimol seed dressings as well as total yield.
The Natural Mortality of Wheat Bulb Fly Pupae, Leptohylemyia coarctata (Fall.) (Dipt., Anthomyiidae)*
Authors: RYAN M. F.
Published: April 2007

The effect of predators and parasites on the mortality of wheat bulb by pupae was studied in the field at Rothamsted Experimental Station, Harpenden, Hertfordshire, from 1964 to 1966. In two populations of pupae studied, 34 and 27 per cent were destroyed by predators, possibly carabid beetles. In two other populations, losses of 15–61 per cent and 29 per cent were also ascribed to predators. A fualher 0·5–5·8 per cent of pupae were killed by parasitic Hymenoptera.
The Role of Graminaceous Species in the Epidemiology of Sieptoria tritici on Wheat
Authors: BROKENSHIRE T.
Published: April 2007

Graminaceous species and cultivars were screened under glasshouse conditions for reaction to inoculum of Septoria tritici. An agar plate test was used to record positive infections and successful isolations were subcultured on to Czapek Dox V‐8 agar under continuous near‐ultraviolet irradiation to induce spore production for pathogenicity tests on the wheat cv. Maris Ranger. Koch's postulates were followed for each graminaceous isolate. S. tritici was recorded on 11 species, but pycnidial development was restricted to eight species. Differences in reaction to S. tritici were observed within barley and tall fescue cultivars. All graminaceous isolates were pathogenic on wheat seedlings and significant differences in pathogenicity were recorded. The ro1e of graminaceous species as alternative hosts in the epidemiology of S. tritici on wheat is discussed.
Colorado Beetles Reported in England and Wales, 1974
Authors: SEYMOUR P. R.
Published: April 2007

In 1974, 59 adults of the Colorado beetle, Leptinotarsa decemlineata (Say), were found, of which 46 were alive. A large proportion were associated with Spanish endives (21) and Portuguese timber (19). No beetles were found on French wheat.
Straw‐borne Inoculum of Septoria nodorum and S. tritici in relation to Incidence of Disease on Wheat Plants
Authors: HOLMES S. J. I. , COLHOUN J.
Published: April 2007

Pycnidia developed within 21 days on pieces of straw inoculated with Septoria nodorum or S. tritici when these were placed among wheat seedlings in the field in mid‐November. As a result of inoculation In this manner infection of young plants readily occurred, although plants In control plots 12 m away remained healthy. S. nodorum can be transported across paths 0·92 m wide and relatively free from vegetation. The possibility of spores of S. nodorum and S. tritici being transported in water droplets for longer distances is discussed.
Effects of Benomyl and Other Fungicides on Take‐all, Eyespot and Sharp Eyespot Diseases of Winter Wheat
Authors: PREW R. D. , McINTOSH A. H.
Published: April 2007

In field trials at Rothamsted, benomyl, thiabendazole, oxycarboxm and ‘Plondrel’ were tested as sprays or seed dressings on winter wheat. None of the treatments affected take‐all (Gaeumannomyces graminis) but benomyl and thiabendazole sprays decreased eyespot (Cercosporella herpotrichoides) and increased sharp eyespot (Rhizoctonia solani). Further field and glasshouse experiments confirmed that sharp eyespot was increased by the application of benomyl and showed that it was also increased by the absence of C. herpotrichoides.
Larval Emergence from Cysts of Twelve Isolates of Heterodera rostochiensis and H. pallida reared on Resistant and Susceptible Tomatoes
Authors: ELLIS P. R. , HESLING J. J.
Published: April 2007

In laboratory tests cysts of 12 isolates of potato cyst eelworms Heterodera rostochiensis Woll. and H. pallida Stone reared on Lycopersicon peruvianum B6001 (which is resistant to H. rostochiensis) and L. esculentum (tomato)‘Ailsa Craig’ were subjected to hatching stimulation in potato‐root diffusate. Larval emergence from isolates in which H. pallida predominated was more rapid than that from isolates in which H. rostochiensis predominated. Possible reasons for this difference are discussed.
Rearing Tipula oleracea (Diptera, Tipulidae) in Laboratory Cultures
Authors: CARTER J. B.
Published: April 2007

Tipula oleracea L. was cultured in the laboratory at 20°C, producing five to six generations per year and, for example, 20,000 surplus insects for experimental purposes. The eggs were kid in agar and the larvae were reared in sand and Fed dried, powdered grass. Small insects such as sciarids contaminated the culture but were controlled by mechanical separation and heat treatment of the sand. This method has been used to rear T. oleracea through 35 generations.
Potato Seed Tubers do not Transmit Top‐roll
Authors: GIBSON R. W.
Published: April 2007

When progeny tubers from potato plants affected with top‐roll were used as seed, the resulting plants showed neither top‐roll nor decreased yield. This is consistent with the hypothesis that top‐roll is caused by aphid feeding rather than by an aphid‐borne pathogen.
Arabis Mosaic Vims, a Cause of Chlorotic Symptoms in Leaves of Fraxinus excelsior L.
Authors: COOPER J. I.
Published: April 2007

Arabis mosaic virus (AMV) was detected in leaves of four Fraxinus excelsior L. trees showing chlorotic mottling, chevrons or oak‐leaf patterns and growing in soil infested with virus‐carrying Xiphinema diversicaudatum Micol. Using an isolate of AMV from ash, inoculated leaves of F. excelsior seedlings developed chlorotic local lesions and a transient chlorotic chevron formed in two leaflets on one of 18 systemically infected plants. Two of 10 F. ornus L. seedlings inoculated and systemically infected with the same ash isolate of AMV developed mild chlorotic mottle symptoms.
Experiments on the Control of Slugs in Potatoes by means of Molluscicidal Baits
Authors: RaynerPL J. M.
Published: April 2007

Field experiments ia several counties in England in 1968–70 demonstrated that three per cent metaldehyde or four per cent methiocarb baits applied in the spring, before or soon after planting potatoes, could reduce slug damage to the ware crop by 50 per cent. Better control was achieved by applications made in July, August or September, although this was not always adequate.
Blackleg of Potatoes: Induction through Tuber InocuIation
Authors: ERINLE I. D.
Published: April 2007

Seed tubers of cv. Majestic were inoculated with isolates of Erwinia carotovora from the Canary Isles, Egypt and the United Kingdom in order to determine which of the isolates could induce blackleg in progeny plants. This technique was found to be very reliable for differentiating between the blackleg pathogen, E. carotovora var. atroseptica and the taxonomically similar pathogen, E. carotovora van carotovora. Study of certain strains of E. carotovora from the Canary Isles, Egypt and Northern Ireland emphasized the importance of relating physiological and pathological characteristics in the understanding of intraspecific variation within this group of bacteria.
Population Studies of Stem Eelworm (Ditylenchus dipsaci) in Microplots, Field Plots and Fields in the North of England under Different Crop Rotations
Authors: WILSON W. R. , FRENCH N.
Published: April 2007

Observations of soil populations of Ditylenchus dipsad (Kühn) Filipjev were made in the north, of England from 1963 to 1969. Samples were taken in spring and autumn or winter from the same 14 commercial fields where oat cultivars susceptible to D. dipsad had been damaged previously by this pest, from field plots under different rotations and different weed control programmes. and from microplots under different crop rotations.

In fields and field plots growing cereals, populations generally increased during summer and decreased during winter. Large increases occurred, when oats were grown. With swedes, potatoes and ley, slight reductions occurred daring summer and larger reductions during winter. Seven of the 14 sites contained populations below detectable levels after 2–8 years without an oat crop; in the remainder, detectable numbers were still present 1–7 years after an oat crop. Field plots receiving no herbicide maintained larger soil populations of D. dipsaci. Approximately 40–60 per cent of oat plants were damaged in crops grown after one or two years’ barley and about 20 per cent after three years’ barley whether or not herbicides had been applied.

In microplots kept weed free, three years of barley, grass, or barley/ grass rotation, three or four years’ fallow or three or four years’ weeds reduced soil levels of D. dipsaci by 99–100 per cent. After all these rotations one oat crop increased the soil population to detectable levels and a second oat crop showed symptoms of damage.
A Comparison of Maturation Feeding of the Elm Bark Beetles Scofytus scofytus (F.) and S. multistriatus (Marsh.) on English Eta (Ulmus pracera Salisb.) and six otter Elm Taxa
Authors: WALKER C. , ROSS RUTH
Published: April 2007

In laboratory experiments elm bark beetles (Scolytus scolytus and S. multistriatus) were allowed to choose between English elm and one of six other taxa (Smooth‐leaved, Wheatley, Wych, Huntingdon, Commelin 274 and Cornish) for maturation feeding. Preference was sometimes shown for English elm over Huntingdon and Commelin elms and, on one occasion, Wheatley elm was fed on more than English. However, there was no consistent pattern. Sufficient feeding occurred on all taxa to enable spores of the Dutch elm disease fungus (Ceratocystis ulmi) to be introduced to the twigs.
Wheat Debris as an Inoculum Source for Seedling Infection by Septoria tritici
Authors: BROKENSHIRE T.
Published: April 2007

Wheat debris was found to be a possible inoculum source for early seedling infection by Septoria tritici. After 50 days, spores from buried debris showed less than 10 per cent viability whilst those from surface debris showed 70 per cent viability. Pathogenicity on wheat seedlings declined with viability. Samples of surface debris from a naturally infected winter wheat crop showed pycnidiospore viability and pathogenicity on wheat seedlings six months after harvest. Maximum pycnidiospore production, on debris occurred after a period of high humidity. Spore production on debris occurred in cycles; the number of cycles and intensity of sporulation depended on the wheat cultivar. Possible control measures to limit disease carry‐over on debris are discussed.
Biological Studies and Chemical Control of Brown Scale (Parthenolecanium corni (Bouché)) on Red Currant
Authors: WARDLOW L. R. , LUDLAM F. A. B.
Published: April 2007

In 1972 and 1973 biological observations were made on brown scales infesting red currant bushes in a plantation in Kent. Scales matured between the end of May and the second week of June, eggs were first found at the end of June and larvae hatched during the first week of August each year; these times are about one month later than previously recorded. Up to 2,011 eggs were found under a single mature scale. In chemical control tests in the same plantation, tar oil winter wash gave good control of the pest; lime sulphur winter wash was less effective but reduced the numbers of scales significantly. Spring application of dimethoate, Fenitrothion or malathion killed most overwintered scales, but endosulfan was ineffective. Suspensions of malathion, dimethoate, diazinon, fenitrothion, demeton‐S‐methyl, dichlorvos, tar oil or lime sulphur killed 92–100 per cent of larvae on the foliage.
Some New Viruses of Grasses and their Relationship with Phleum Mottle Virus
Authors: CATHERALL P. L. , CHAMBERLAIN JUDITH A.
Published: April 2007

Cocksfoot mild mosaic and two hitherto unreported viruses, one from bromegrasses and one from Holcus lanatus, were isolated from grasses collected in north and mid Wales. All had isometric particles c.28 nm in diameter and were transmissible by sap inoculation, but they differed in their host‐range and symptomatology. Serologically, none were identical, but all were sufficiently closely related to each other and to phleum mottle virus to be considered as strains of a single virus.
Growth of Erwinia carotovora var. atroseptica and E. carotovova var. carotovora in Potato Stems
Authors: ERINLE I. D.
Published: April 2007

The growth of Erwinia carotovora var. atroseptica and E. carotovora var. carotovora in stems of potato cultivars Majestic and Red Craigs Royal is reported. At high daily maximum temperatures, all isolates grew logarithmically for varying periods. Thereafter E. carotovora var. atroseptica populations generally increased and incited blackleg, while E. carotovora var. carotovora remained stationary or fell and either failed to incite blackleg or brought about a fast soft rotting (hollowing‐out) of the stems. Growth of either variety, especially of E. carotovora var. carotovora was retarded at lower daily maximum temperatures. There was a reduced growth in Red Craigs Royal compared with Majestic.

For the blackleg symptom to appear in Majestic, a threshold population of c. 108 bactcria/g of stem was considered a pre‐requisite.