bluuebunny/crossref_metadata_2025_split huggingface dataset:
On The Pigmy Mangold Beetle (Atomaria Linearis Steph.) and Methods for its Control
Authors: EDWARDS E. E. , THOMPSON J. K. 
Published: February 2008

Summary.1. An extensive investigation of the Pigmy Mangold Beetle (Atomaria linearis Steph.) on sugar beet and mangold has been made during the past six years, both in the field and in the laboratory2. The symptoms of attack are given, together with a brief account of the distribution and life history of the beetle.3. General field observations of infested areas both in Lincolnshire and Shropshire indicate that epidemics of the Pigmy Mangold Beetle in sugar‐beet and mangold crops only occur under certain conditions, of which continuous cropping of the land with susceptible plants is usually considered of primary importance.4. It is found that environmental factors have a marked influence on the relative susceptibility of sugar‐beet and mangold crops to serious injury by the beetle. Evidence is produced to show that many of these factors are under the direct command of the grower and their significance on control measures discussed.5. Field experiments on control of the pest show that, of the treatments tested, the use of phenol and magnesium sulphate at the rate of 1 and 5 per cent. respectively, as a seed steep is the most effective.6. There is reason to believe that the common practice on the Continent and in certain districts in this country of sowing crude naphthalene with sugar beet seed as a deterrent against the Pigmy Mangold Beetle results in serious damage to germination.7. Different varieties of sugar beet vary in the degree to which they are liable to infestation but the differences are generally small and unimportant. Mangolds, as a rule, are more resistant than sugar beet.8. In addition to mangold and sugar beet, the beetle is recorded for the first time in Great Britain on garden beet and White Goosefoot (Chenopodium album). Some evidence is presented to show that a rotation of crops as means of control of the beetle may be ineffective in areas where White Goosefoot prevails.
III. Injection for the Diagnosis and Cure of Physiological Disorders of Fruiot Trees.
Authors: Roach, W. A. 
Published: February 2008

Summary.Water and sand‐culture methd are of somewhat limited applicability to fruit trees.The interpretation of the results of manurial experiments, whether conducted in the field or in pots, are complicated by base exchange and similar phenomena. Direct injection of solutions into trees is, therefore, suggested an an additional method for studying, and possibly even curing, physiological disorders, especially those of the “deficiency” type. Methods for injecting whole trees, separate branches, with or without their corresponding roots, or separate twigs are described.Some effects of injection on the vigour of the tree and on disease are mentioned.
COMPETITION IN SEEDS MIXTURES AT HIGH ELEVATIONS (850 FT.) AT MOELGLOMEN, TALYBONT, CARDIGANSHIRE
Authors: THOMAS M. T. 
Published: February 2008

Summary.The experiment was designed to obtain further information on the value of certain species and strains of grasses and legumes for permanent grass on upland, thin soiled, dry fields of low fertility.Their ability to compete in mixtures and their persistency were studied in detail and the evidence indicates, in a general way, that these factors operate in rather a different manner on the uplands as compared to the lowlands.Pedigree cocksfoot is superior in productivity to pedigree perennial rye‐grass, but the need for a small seeding of pedigree perennial rye‐grass to help protect the pedigree cocksfoot during the first few years is suggested.Montgomery red clover has proved itself to be infinitely better than Lotus major, kidney vetch and wild red clover, especially for hay. Of the bottom grasses in the test, smooth‐stalked meadow grass has been a failure, and although rough‐stalked meadow grass made a fair contribution to the second crop of hay when sown at a heavy seed rate, crested dogstail and the fine‐leaved fescues have been far more aggressive. The heavy contribution of crested dogstail to the second‐year hay crop is worthy of note. The aggressiveness of the fine‐leaved fescues in the aftermath of the third harvest year is a factor to be further considered. Chewing's fescue, in distinct contrast to red fescue (pedigree), gets very winter‐burned and unpalatable.Wild white clover is an essential constituent in mixtures for these conditions. It is probable that Italian rye‐grass at 10 or even 12 lb. per acre is not too much where the spring grazing is hard and where the fields are not closed for hay until early May. Indigenous and pedigree strains have given more hay, more leaf and have been more persistent than the commercial strains.
PSYLLIA PEREGRIN A FÖRST., THE HAWTHORN RACE OF THE APPLE SUCKER, P. MALI SCHMIDB.
Authors: LAL K. B. 
Published: February 2008

Conclusions and SummaryThe conclusions based on these investigations may be summarised as follows:“P. peregrina” and P. mali of hawthorn are identical, and are only the seasonal forms of one and the same species. These insects are also morphologically indistinguishable from P. mali o. apple.The nymph of the forms occurring on hawthorn is different from the typical nymph of the apple sucker (P. mali), and has long been known as the nymph of “P. peregrina.” In it, however, there occurs a small percentage of variations, in which the characteristic brown longitudinal streak of the wing pads does not occur.Although morphologically similar, specimens of P. mali of hawthorn and apple do not mate with each other, nor do they oviposit interchangeably on each other's host plants. The nymph of either when transferred to the food plants of the other does not survive very long. 4. P. mali of the apple has a biological race on hawthorn, which has long been known as P. peregrina. This race should be distinguished as P. mali Schmidb. race peregrina, which is the name it is proposed to assipn to it. The two races, in view of their dissimilar nymphs, furnish an instance of poecilogony.
THE EFFECT OF ENVIRONMENTAL CONDITIONS UPON PYRETHRUM (CHRYSANTHEMUM CINERARIAEFOLIUM). I.
Authors: MARTIN J. T. , TATTERSFIELD F. 
Published: February 2008

Summary.The effect of soil fertility upon the insecticidal value of the flowers has been studied in a series of pot experiments. On heavy soil the pyrethrin I content of the flowers was not increased by the application of fertilisers. The plants produced good yields of flowers, rich in pyre‐thrins, when grown in soil of low fertility.Under conditions of normal growth and vitality, the extent of production of the pyrethrins in the flowers was characteristic of the individual plant and was dependent upon some factor which appeared to be genetical in character. A plant initially producing flowers of high or low percentage poison content continued to give flowers of the corresponding degree of richness in succeeding years, independently of the application of manures, or apparently of the number of heads produced. Plants derived from rooted shoots produced flowers corresponding in quality with those initially yielded by the parent plant. The insecticidal value of pyrethrum flowers may be improved by plant selection, followed by vegetative propagation.In the fully open flowers, the complete disc florets contained 90 per cent. of the total pyrethrins present in the flowers, and of this the greater part was found to be located in the ovaries.
THE PHYSICAL ENVIRONMENT OF SCOTTISH AGRICULTURE IN RELATION TO CROP IMPROVEMENT PROBLEMS1
Authors: SNODGRASS C. P. 
Published: February 2008

Summary.

The co‐ordination of the available data relating to the environmental conditions of agricultural regions is advocated as a means of facilitating the testing and ultimate distribution of new crop varieties.
The physical environment (topographical, geological, climatic and edaphic) of three agricultural regions is described, and its influence on the length of the growing season, the length of crop rotation, and the distribution of the principal crops is discussed.
Taking the parish as the unit, maps for the three regions are given to illustrate the mean elevation of cultivated land (Figs, 1a, b and c), the estimated accumulated temperatures (Figs. 2a, b and c), the mean annual rainfall (Figs. 3a, b, c and d), the percentage of farm land under rotation (Figs. 4a, b and c) and the length of rotation (Figs. 5a, b, and c).
FURTHER STUDIES ON QUANTITATIVE METHODS WITH TWO PLANT VIRUSES
Authors: SAMUEL GEOFFREY. , BEST R. J. , BALD J. G. 
Published: February 2008

Summary.The arrangement of experiments for intercomparison of a number of virus samples is discussed and the use of randomised blocks or Latin squares, combined in certain cases with half‐leaf comparisons between all samples or against a standard, is recommended.Improvements in the ground‐glass spatula method of inoculation have been suggested.Provided there is sufficient inoculum to cover the leaf when the spatula is rubbed over it, the amount, of inoculum makes no difference to the number of lesions produced.The conditions to which test plants are subjected shortly before inoculation were found to influence the number of lesions produced by a given inoculum.The number of lesions produced by otherwise similar inocula is influenced by their pH value and electrolyte content. The optimum pH. range for the virus of tomato spotted wilt is very limited (roughly pH 6.0–8.5). Tobacco mosaic virus in a potassium phosphate buffer at a pH value about 7 produced the maximum number of lesions in the concentration range 0.05‐0.2M. It is recommended that for most quantitative work viruses should be buffered at a definite pH value.When effects due to varying pH value and electrolyte content were excluded, the virus of tomato spotted wilt was still found to be inactivated by certain oxidising agents and preserved by certain reducing agents.
INSECT INJURY SIMULATING FUNGAL ATTACK ON PLANTS
Authors: LEACH R. 
Published: February 2008

Summary.

Four different types of disease of the mango tree are shown to be caused by the capsid bug, Helopeltis bergrothi Reut.
Symptoms of a stem canker, an angular leaf spot, a fruit scab and a fruit rot of mangoes are described.
A description of the morbid anatomy of these diseases is given.
References to control measures advocated against H. bergrothi are cited.
A discussion of the results shows the possibility of the importance of further co‐operative work between entomologists and mycologists in the study of plant diseases.
INCIDENCE OF TAKE‐ALL ON WHEAT AND BARLEY ON EXPERIMENTAL PLOTS AT WOBURN
Authors: GLYNNE MARY D. 
Published: February 2008

Summary.Surveys were made in 1931, 1932 and 1933 of the incidence of take‐all on wheat and barley grown in the continuous experiments at the Woburn Experimental Station. Ten random samples consisting of all the plants in two half‐metre lengths separated by a metre and taken from adjacent rows were obtained from each plot. The numbers of clean and diseased plants, their tillers and yield of straw and of grain were determined for each sample. No manure had been applied since 1925‐6 except to certain of the barley plots.There was little or no take‐all on plots which had received ammonium sulphate alone, with minerals, or with 1–2 tons of lime, while the disease was present in most of the other plots.In general there was a higher percentage infection on wheat, reaching a maximum of 52.5 per cent, on one plot, than on barley in which the highest percentage infection on any plot was 16.2.Little or no take‐all appeared on either wheat or barley in plots whose pH. was 5 or less, comparatively little at pH 5.1 and in general considerably more at higher pH values. In spite of considerable variation in infection at the same pH. values there was a general tendency for percentage infection to rise with pH in wheat, but this was not apparent in barley.The wheat plot 10 B which had received rape dust was exceptional in that though it had a pH. of 5.4 little infection appeared. The corresponding barley plot also had little infection but its pH. was only 5.1. No clear relationship between yield and incidence of take‐all was found.In the three years in which observations were made take‐all appeared to increase in wheat till 35 per cent, of the plants were infected and then to decrease. Two years' observations on barley suggest that the corresponding figure for this crop is about 10 per cent.The total number of plants obtained from all the wheat samples increased slightly from 1931 to 1932 and decreased by more than half in 1933. The average percentage of take‐all increased considerably from 1931 to 1932 and remained about the same in 1933.The average loss in yield due to take‐all in thirteen affected plots rose from 16 per cent, in 1931 to 20 per cent, in 1933, with a maximum loss in any plot of 42 per cent.A white mycelium belonging to an Agaric of the Cortinarius type was found frequently on the roots and basal parts of wheat and barley. In general it did not appear parasitic but there is some evidence that in certain plots it had become so, causing considerable loss in yield.Take‐all was very much less on wheat grown in alternate years with green manure intervening than on the continuous wheat.
FURTHER EXPERIMENTS ON THE ARTIFICIAL FEEDING OF MYZUS PERSICAE (SULZ.)
Authors: HAMILTON M. A. 
Published: February 2008

Summary.

A method is described for the feeding of Myzus persicae on media of which one constituent is a radioactive indicator containing polonium.
The results show that Myzus picks up the indicator from the medium and transmits it to a leaf on which it is subsequently fed.
The volumes imbibed are of the same order of magnitude as those imbibed by aphids under natural feeding conditions.
A constant proportion of the amount imbibed is transferred to the leaf, from which it is deduced that the polonium is transmitted through the bodies of the aphids and not on the outsides of the stylets.
Evidence is given to show that the virus probably behaves in the same way as the polonium.
OBSERVATIONS ON THE TIMOTHY GRASS FLY (AMAUBOSOM A ARMILLATUM ZETT.)
Authors: KING L. A. L. , MEIKLE AGNES A. , BROADFOOT A. 
Published: February 2008

Summary.

A type of damage to the inflorescence of Timothy grass, which appears to be widely distributed, has been found in the west of Scotland to be due to Amaurosoma armillatum Zett.
Information is given as to occurrence in the field, method of attack on the plant, life history and characteristics of the insect in its different stages. Three larval instars are distinguished and the life history is noted as monocyclic.
Two Hymenopteron parasites are recorded.
Experiments are described which were designed to test possible methods of control (a) by soil‐treatment, (b) by deterrents.
Of the latter an emulsion of crude naphthalene in ground‐nut oil is recommended as promising.
It is suggested that the grass to be reserved for seed should be set apart early in the season and sprayed with this fluid at a time as near as possible to that of the egg‐laying.
SHEEP BLOWFLY INVESTIGATIONS
Authors: DAVIES W. MALDWYN , HOBSON R. P. 
Published: February 2008

Summary.The present paper is intended as the first of a series dealing with various aspects of the sheep maggot problem, especially the causes of susceptibility. Since this pest is more common in moist weather, an investigation was made of the effect of humidity on sheep maggots; also, a method was devised for studying the humidity at the base of the wool–the site of attack.The following is a brief summary of the results obtained:

The eggs and young larvae of Luclia sericata Mg., the sheep maggot fly, are extremely sensitive to desiccation at 37° C.
Dry conditions prevail in the fleece near the skin, except in the region of the rump, and the relative humidity seldom exceeds 70 per cent., even during wet weather.
These results show that the microclimate at the base of the wool is normally too dry for the development of maggots; this has been confirmed by finding desiccated eggs and larvae on sheep in the field.
Sheep do not become infested with maggots unless predisposing conditions are present; the humidity at the base of the wool appears to be the main factor which determines susceptibility.
The wool around the rump is often moist owing to soiling with faeces and urine, the humid conditions favouring the development of eggs and maggots.
STUDIES ON THE SECRETION OF DIASTASE AND INVERTASE BY EMPOA8CA SOLAN A DELONG (RHYNCHOTA, HOMOPTERA, JASSIDAE)
Authors: HERFORD G. V. B. 
Published: February 2008

Summary.

It has been shown that adults and nymphs of the Jassid, Empoasca solaria DeLong, are able to eject diastase into the feeding medium.
This diastase, besides being secreted in the salivary glands, is apparently also formed by certain yeasts which are regurgitated from the gut of the insects.
A technique is described for feeding the leaf‐hoppers on a liquid.
The insects have also been shown to be capable of secreting an enzyme, probably invertase, which has the power of inverting pure sucrose.
EXPERIMENTS WITH FOLLICULAR AND OTHER HORMONES AND PLANT GROWTH
Authors: TINCKEK M. A. H. 
Published: February 2008

Summary.In the experiments described the writer failed to obtain accelerated growth or acceleration of flowering by presenting small quantities of ketohydroxyoestrin and theelol to flowering plants in different ways—in solution given to the roots, or by injection, or when applied to cut surfaces.From one experiment, designed for another purpose, possible confirmation of the results of Knight and Fildes was obtained in that auxin accelerated bacterial growth.
FURTHER EXPERIMENTS ON THE FUSARIUM BULB ROT OF NARCISSUS
Authors: HAWKER LILIAN E. 
Published: February 2008

Summary.1. Experiments on the inoculation of roots of Narcissus with Fusarium bulbigenum in the autumn show that, under suitable conditions of moisture and rather high temperature, the fungus is able to penetrate and destroy the roots of all varieties tested. Under similar suitable conditions it can penetrate bulbs of susceptible varieties via the parasitised roots. It is concluded that temperature conditions in England are seldom favourable to such penetration via the young roots during the autumn.2. Some evidence is given that penetration of the bulbs may take place via the old roots at the end of the growing season when soil temperature is likely to be more favourable to attack. Further work on this point is desirable.3. Gregory's statements that heavy losses from Fusarium may follow the standard hot‐water treatment against bulb eelworm, when carried out in the autumn, and that in such cases penetration usually takes place at the base of the bulb are confirmed and amplified.4. Experiments in which bulbs were hot‐water treated, with the addition of Fusarium spores to the water, at intervals during the storage period, indicate that bulbs pass through, a phase of minimum susceptibility in late August and early September, i.e. at the normal time of bathing.5. It has been shown that, where bulbs are hot‐water treated in the presence of Fusarium spores, the addition of formalin (0.1 per cent. or more) to the water materially reduces the resulting losses.6. A comprehensive series of experiments, with fourteen varieties, has been carried out during four seasons in order to test the effects of the addition of fungicide to the hot‐water bath. These experiments, for reasons which are discussed fully in the text, have not yielded any conclusive evidence on the effect of this treatment on the spread of the disease. It has been amply shown, however, that the incorporation of 0.1‐1.5 per cent. formalin in the bath has no harmful effects on foliage, date of flowering, quality and number of blooms or amount of increase in weight of bulbs during the growing season, but is often beneficial.7. Cold steeps in 0.1 per cent. mercuric chloride solution led to a retardation of the date of flowering.8. It is desirable that fungicidal treatment should take place before the normal date of hot‐water treatment, and experiments are in progress to test the efficacy of various cold steeps and dry dustings carried out in the early part of the storage season.In conclusion the writer wishes to express her thanks to Prof. W. Brown, who suggested this work, for much advice and assistance during its progress. Thanks are also due to Dr A. K. Ghamrawi who carried out some of the observations in the 1931 experiments.
STUDIES ON EUROPEAN FOUL BROOD OF BEES
Authors: TARR H. L. A. 
Published: February 2008

Summary.An unidentified bacillus which appears to replace B. alvei in certain cases of European foul brood has been isolated from two different cases of this disease.Strains of B. alvei from various sources exhibit certain differences in their fermentative powers, and it is suggested that these may form a basis for differentiating strains of this organism.The etiology of European foul brood is discussed.
A NEW VIRUS DISEASE OF THE TOMATO
Authors: SMITH KENNETH M. 
Published: February 2008

Summary.A new virus disease of the tomato plant is described. An account is given of the symptoms produced on a variety of host plants, mostly in the Solanaceae. Some of the physical properties of the virus have been investigated and its particle size measured by ultrafiltration through Gradocol membranes. The size as measured by filtration in plant sap is approximately 17–25 mμ. The virus is compared with other viruses commonly affecting tomato and tobacco and methods of differentiating them are discussed.
AN ACCOUNT OF THE CONSTITUTION AND USE OF AN ATOMISED WHITE OIL—PYRETHRUM FLUID—TO CONTROLPLODIA INTERPUNCTELLAHB. ANDEPHESTIA ELUTELLAHB. IN WAREHOUSES
Authors: POTTER C. 
Published: February 2008

Summary. The problem of the infestation of imported stored products by the Phycitid moths,Ephestia elutellaHb. andPlodia interpunctellaHb., is outlined. An outline account is given of the life history ofEphestia elutellaHb. andPlodia interpunctellaHb. in the London warehouse. The specification of the insecticidal material used is given, together with a description of its properties and the factors influencing its choice. An account is given of inflammability tests on the material when in an atomised state. The apparatus used is described. The process as used against moths is described. The process as used against migrating larvae is described. The precautions which should be taken by operators are given. An account is given of a series of biological tests and observations made on the effects of this material and process on the moths and larvae ofPlodia interpunctellaHb. andEphestia elutellaHb.
ON THE OCCURRENCE OF APLANOBACTER RATHAYI E. F. SMITH ON DACTYLIS GLOMERATA IN ENGLAND
Authors: DOWSON W. J. , D'OLIVEIRA M. 
Published: February 2008

Summary.

The occurrence of baeteriosis of D. glomerata, with which is associated the non‐motile organism A. Rathayi E. F. Smith, is recorded for Cambridgeshire definitely for the first time, but there seems little doubt that the disease has been present unrecognised for some time and is being constantly introduced on imported Danish seed.
The disease is similar to that originally observed near Vienna in 1897, but differs from the latest account from Germany where the damage caused was far more severe. The general symptoms were partial or complete destruction of the spikelets which were embedded in a bright yellow bacterial slime.
The associated organism was isolated and found to agree exactly in its cultural and growth characters with the descriptions of Rathay and Smith.
The naturally occurring bacterial slime proved pathogenic when inoculated into a healthy shoot of Dactylis, but no infection resulted when pure cultures on artificial media were used.