bluuebunny/crossref_metadata_2025_split huggingface dataset:
AN APPARATUS FOR TESTING AND COMPARING THE BIOLOGICAL ACTION OF INSECTICIDES ON FLYING INSECTS AND A METHOD FOR SAMPLING THE CONCENTRATION OF THE ATOMIZED INSECTICIDE
Authors: POTTER C. , HOCKING K. S. 
Published: February 2008

Summary

An apparatus and method for testing the effect of atomized sprays on flies and mosquitoes are described. The apparatus consists of a revolving wire gauze cage placed in a thermostatically controlled chamber, the whole of which may be easily cleaned and freed from toxic residues. The insecticide is sprayed into the chamber by means of an Aerograph MP gun and distributed by means of a slow‐moving fan. When the insecticide has been injected and an interval allowed for the initial rapid fall of concentration, the movement of the cage is stopped and the insects are introduced into it by means of a special tube and plunger. The time required for paralysis to take place is recorded. After a given interval the insects are removed from the gauze cage and kept to ascertain the mortality.
A technique for sampling the concentration of insecticide in the air space is described. The insecticide carrier is coloured with a dye, Sudan III for petroleum oil bases and methylene blue for water bases. The percentage of atomized material remaining in the atmosphere at any given time is determined by aspirating a known quantity of the atmosphere of the chamber through a sintered glass filter. The dye is retained in the filter, it is washed out with a measured quantity of liquid and compared with known standards. Reasons are given for the assumption that the dye molecules will behave in the same way as the insecticide molecules.This sampling method has been used to study the behaviour of a light oil, a heavy white oil and water at different degrees of atomization. Tables and graphs are given which show that, except with a fine atomization where most of the insecticide remains suspended for a considerable time, there is an initial rapid fall, which varies in amount with the degree of atomization. This initial fall is followed by a much more gradual decrease of concentration. The experiments show clearly that oil bases of different physical properties cannot be compared adequately unless a sampling method is used to ascertain the quantities of material remaining suspended. Where water bases are used it is shown that the time concentration curve varies not only with the degree of atomization, but also with the degree of saturation of the atmosphere before spraying. The concentration remains higher in an unsaturated atmosphere than in a saturated one.
OBSERVATIONS ON APPLE CANKER
Authors: MUNSON R. G. 
Published: February 2008

Summary

The fungus causing apple canker is described and its identity with Nectria galligena Bres. is confirmed.
The methods of dispersal of the spores of Ngalligena have been examined. The ascospores are discharged forcibly from the perithecium, the eight spores of each ascus typically being ejected simultaneously.
Field investigations have shown that spores are discharged during wet periods at all times of the year. Ascospore discharge reaches its maximum in January‐February and falls to a minimum in the summer months.
The dispersal of conidia occurs during wet periods in the spring and autumn.
Germination both of ascospores and conidia occurs over a range of temperature from 2 to 30°C, the optimum being at 20°C.
OBSERVATIONS ON APPLE CANKER
Authors: MARSH R. W. 
Published: February 2008

Summary

Inoculations with N. galligena on unwounded shoots of apple show that canker infections through leaf scars may be initiated in October and April but not in November and January. Shoots sprayed before inoculation with a Bordeaux‐casein‐oil mixture gave a much lower proportion of infection than those unsprayed.
Inoculations with N. galligena on pruning cuts showed that freshly made pruning cuts on apple shoots are susceptible to canker infection throughout the dormant season. Pruning cuts made during autumn and winter acquire a natural immunity to infection within 2 months.
Several wound sealing materials applied to pruning cuts failed to give protection from canker when the treated surfaces were inoculated with N. galligena. The most promising wound protectant tested was a mixture of monohydrated copper sulphate, hydrated lime and linseed oil.
SUCCESSION OF FUNGI DECOMPOSING WHEAT STRAW IN DIFFERENT SOILS, WITH SPECIAL REFERENCE TO FUSARIUM CULMORUM
Authors: SADASIVAN T. S. 
Published: February 2008

SummaryA study has been made of the sequence of fungi developing on wheat straw buried in four arable soils, an allotment soil, and a glasshouse compost. Both natural untreated straw, and straw autoclaved in a 2 % solution of sodium nitrate were employed. Fusarium culmorum and Mucor spp. appeared to be dominant organisms in the earlier stages of straw colonization, but these were replaced by Penicillium spp. in the latter stages of decomposition. The nitrogenous treatment of the straw favoured the development of Penicillium spp. at the expense of Fusarium culmorum and Mucor spp. The pathogenicity of the Fusarium culmorum isolates to wheat seedlings was established by inoculation experiments.The data provided by this investigation are considered sufficient to justify the inclusion of F. culmorum in Reinking & Manns' (1933) group of soil‐inhabiting Fusaria, or true soil fungi.
THE HISTOLOGY AND PHYSIOLOGY OF ROTENOIDS IN SOME PAPILIONACEAE. I
Authors: WORSLEY R. R. LE GEYT 
Published: February 2008

Summary

All available parts at all available stages of growth, of twenty‐two species of Papilionaceae have been examined microscopically for the presence of rotenoids: fourteen contain them, and Table V summarizes all the plant parts in which they occur.
The rotenoid content varies from mere traces in the seeds only of one species to appreciable quantities in nearly every organ of another species.
Seeds of twelve of the rotenoid‐containing species were available: all contained rotenoids. It appears to be the rule that if any species contains rotenoids in any tissue it will contain them in its seeds.
Roots of thirteen of the species were available: twelve contained rotenoids.
In general, rotenoid cells in the roots and stems are normal ones, but in all other tissues they are usually morphologically distinct, and frequently relatively very large.
Rotenoids occur in the seeds of species of Millettia and Derris not in cells but in iysigenous cavities.
In many species rotenoids are first detected in the cortex of the root opposite the protoxylem and primary medullary rays.
In general, the roots contain rotenoids in the xylem parenchyma, especially in the medullary rays, and in the cortex. In stems they occur mainly in the pith, when not lignified, and also in the phloem, especially in the rays, and in the cortex.
At nodes there is frequently an increase in the number of rotenoid cells, especially in the pith.
On germination, the seeds of Mundulea and Tephrosia species at first produce new rotenoid cells, accompanied by an increase in total rotenoid content, in the growing radicle and in the cotyledons. Later, the rotenoids diminish to nil in the radicle and to between 45% and nil. for different species, in the cotyledons. With Millettia. new rotenoid cavities are at first formed in the radicle, and later all rotenoids disappear from it: only a small reduction in the rotenoid content of the oetyledons, however, occurs. With Derris, no new rotenoids are formed in the radicle: the amount in the cotyledons in one species diminished to 62 %.
Rotenoids in the plumules of Millettia and Derris species disappear soon after germination.
Two instances only of lability of rotenoids have been proved: in the germinating seeds of all species, and in the lignifying pith of the stems of two species.
Derris elliptica plants placed in the dark until dead show no reduction in the amount of rotenone per plant: indicating that the rotenone is not available as a food reserve.
The application of the sap from Derris roots and stems to Derris cuttings produces no increase in percentage rooting or in the speed of rooting.
The results suggest that rotenoids are of some direct use to the germinating seed and seedling, but that they are probably waste products in all other tissues.
THE EFFECT OF CLIMATIC EXPOSURE ON TEXTILE FIBRES AND FABRICS
Authors: THAYSEN A. C. , BUNKER H. J. , BUTLIN K. R. , WILLIAMS L. H. 
Published: February 2008

SummaryVarious textile fabrics were exposed to a wide range of climatic conditions.Those exposed to waterlogged conditions were destroyed rapidly. In the case of cellulose fabrics this destruction was due solely to bacteria, and not to fungi or actinomycetes. In the case of wool, the evidence of microbiological action was not conclusive.Cellulose, wool, silk and cellulose rayon fabrics disintegrated on exposure in microbiologically active soils. The destruction was due to microbiological action, the rate being governed by the moisture content of the soil and, to a lesser extent, by the temperature. Cellulose acetate rayon was completely resistant.Cellulose and wool fabrics exposed in the shade to very humid tropical conditions were damaged much less rapidly than in soil, although there was extensive “mildewing”.“With fabrics exposed for a year in the shade at stations with subtropical or temperate climates, and with a rainfall of about 30 in., the microbiological damage suffered was insufficient to affect the strength of the fabric, but there was much”mildewing“. No microbiological damage or”mildewing“was observed in shade‐exposed fabrics in arid climates where the annual rainfall did not exceed 9·5 in.Where fabrics were exposed to the action of sun as well as rain and wind, microbiological damage occurred when the moisture conditions were suitable for the growth of micro‐organisms. This damage was invariably less than that of fabrics exposed in the shade at the same station.Exposure of cellulose fabrics both in sun and shade caused a lowering in viscosity, whereas soil exposure, which causes more extensive microbiological destruction, did not affect the viscosity. All sun‐ and shade‐exposed samples showed a lowering in pH value during the first 3 months, but subsequent exposure caused little further change. Soil exposure caused practically no change.Inert substances such as glass, metals and rubber, when used as a covering for cellulosic fabrics, retard microbiological decay in soil and sea exposures. Some commercial protective substances owe their value to their shielding action. The parenchymatous and epidermal tissues surrounding the fibre bundles of jute exert no shielding effect. In a micro‐biologically active soil, flax, hemp and jute fabrics decay at approximately the same rate as cotton, which contains no protective tissue.A provisional technique is described by which the relative merits of “mildew”‘ protective treatments may be evaluated. The only treatment which has been found to give permanent protection in the case of cellulosic fabrics is partial acetylation.
STUDY OF BYSSOCHLAMYS FULVA AND CONTROL MEASURES IN PROCESSED FRUITS
Authors: HULL R. 
Published: February 2008

Summary

A survey of various fruit‐producing areas in England showed that fruit and foliage were liable to be contaminated with ascospores of Byssochlamys fulva. Contamination was most pronounced on mummified plums and on certain fruit refuse.
The thermal death point of ascospores is about 96°C., but only a small proportion of spores show this maximum heat resistance. Conidia are killed by exposure to relatively low temperatures.
The reaction and the sucrose concentration of the heating medium, and the strain of the fungus, are factors influencing the heat resistance of ascospores.
Ascospores germinate slowly and irregularly, but their germination is stimulated by previous heating to about 70°C. Ascospore germination and mycelial growth take place at relatively high temperatures, in high sucrose concentrations, in acid media, and in very high concentrations of carbon dioxide.
Ascospores are relatively insensitive to antiseptics and to desiccation.
Growth is accompanied by the production of a pectin‐destroying enzyme.
The results of laboratory experiments were applied to canning experiments and good agreement was obtained. Natural contamination on fruits could be overcome in cans by heating the contents to 195°F.
The amount of mycelial growth developing in an infected can depends upon the size of head space and the storage temperature.
THE INTERNAL TEMPERATURES OF FRUIT TREE BUDS
Authors: Grainger John 
Published: February 2008

SummaryAn account is given of the distributions of heat and relative humidity from three methods of orchard heating, together with the results of experiments with a simple type of humidified heating. Ignited balls of papier mache which had been soaked in crude oil, were humidified with saturated garden refuse, such as long grass or lawn clippings. This arrangement heats the air, and at the same time either maintains or enhances the relative humidity. No lowering of the internal temperature of the bud is produced, and the method helps to control a frost at its source, by diminishing radiation of heat from the earth to an open sky. Frosts may therefore be controlled in practice by the expenditure of about one‐third the fuel used in the flame‐type heaters.Lateral distribution of heat from orchard heaters is not great. Suggestions are made for the alternate disposition of fruit trees and heaters upon a slope. Advantage may thereby be taken of the katabatic wind which occurs during a radiation frost, to direct the heated air towards the trees.
Experiments to determine the effect of certain wood preservatives on the growth and cropping of the cultivated mushroom (Psalliota campestris)
Authors: Pizer N. H. , Glasscock H. H. 
Published: February 2008

A small‐scale laboratory method of determining the effect of wood preservatives on growth and cropping of the cultivated mushroom is outlined. Experiments with a number of well‐known wood preservatives are described. According to these experiments wood treated with the following preservatives had no adverse effect on mycelial growth or on croppings: 5 % copper sulphate solution, green Cuprinol, 5 % Celcure solution, 2 % Triolith (Wolman salts) solution. On the other hand, wood treated with 2 % Chromel salt and coal‐tar creosote reduced the vigour of growth of mushroom mycelium to a depth of 1/2 in. in compost that was in contact with it. Under these conditions, however, the mycelium was not killed nor was the cropping reduced even when the treated wood was only 1 1/2 in in. below the casing soil. As in all experiments the treated wood was covered with compost, the chance of vapours from the preservatives coming into contact with sporophores was very small, and the possibility of harmful effect in mushroom houses from such vapours should not be ignored.The experiments indicate that full‐scale trials in commercial mushroom houses could be undertaken with copper sulphate, green Cuprinol, Celcure and Triolith with negligible risk to the crop, but that it is advisable to carry out trials on a smaller scale with Chromel and coal‐tar creosote of known composition to determine whether these preservatives have any adverse effect on cropping. Owing to the great range in composition shown by coal‐tar creosote it is most important that the conclusions reached with the particular sample used in the above experiments should not be applied to creosotes in general.
Value of phloem necrosis in the diagnosis of potato leaf‐roll
Authors: Sheffield F. M. L. 
Published: February 2008

In plants infected with leaf‐roll virus a type of phloem obliteration and necrosis occurs which is distinct from any abnormality produced by other pathogens or arising from physiological causes. The necrosis occurs in the primary phloem only of the bicollateral bundles. The affected tissue reacts with phloro‐glucinol in HCI. It was present in all of 179 plants of 33 varieties showing secondary leaf‐roll which were examined and was not found in any of 83 healthy plants of 20 varieties. The amount of necrosis varies in different plants. If the disease is severe, necrosis may extend to almost all parts of the plant except the stolon, tubers and roots. If the infection is mild it may be confined to a very few strands in two or three nodes near the base of the main stem. Phloem necrosis can always be found before leaf rolling is apparent.In primary leaf‐roll, slight necrosis can be found in the stem near the bases of the lowest rolled leaves and sometimes in the petioles.A technique is suggested for the use of this symptom in diagnosis.
Experiments on the poisoning of honeybees by insecticidal and fungicidal sprays used in orchards
Authors: Butler By C. G. , Finney D. J. , Schiele P. 
Published: February 2008

Losses of bees by poisoning have been greatly increased in recent years by the growing practice of applying insecticidal and fungicidal sprays to fruit trees. Preliminary laboratory tests showed that, of the common constituents of spray mixtures, only lead arsenate and flowers of sulphur were likely to cause serious honeybee poisoning, though Derris emulsion may cause slight poisoning. Syrup containing lime sulphur, nicotine sulphate, or copper sulphate was strongly repellent to the bees.It seemed possible that spray mixtures might be made repellent to the honeybee by the addition of suitable substances. Further trials showed that lead arsenate solution, at least in the concentrations normally used, was no more attractive to the bee than distilled water. Concentrations of 1/500 lime sulphur or 1/2000 nicotine sulphate were sufficient to reduce the uptake of M/1 sucrose to less than 10% of that of unadulterated sucrose solution, and very much lower concentrations appreciably affected the uptake. The presence of lead arsenate in these solutions seemed to make them even more repellent. The repellent effect was reduced, though not entirely destroyed, when the solutions were evaporated to dryness and taken up in distilled water again.Creosote (0.13%), which has been suggested as a possible repellent, gave erratic results under laboratory conditions, and, in view of the danger of phytocidal action it is probably unwise to attempt to use its repellent property.Open flowers of apple trees were sprayed with various spray mixtures in an orchard experiment, and counts of bees showed both lime sulphur (1%) and nicotine sulphate (0.05 % nicotine) to have retained their repellent value for at least 7 days, in spite of heavy rain. If bees can thus be deterred from visiting the open blossom, it should be possible to deter them even more thoroughly from collection of water contaminated by sprays applied at the correct time.Data collected throughout the country during the last 3 years show calcium or lead arsenate to be the constituent of orchard sprays causing honeybee poisoning. Bees may collect arsenic when visiting fruit trees, or plants growing beneath or near the trees, for pollen or water, contaminated water apparently being the chief cause of poisoning; about 0.00005 mg. internal arsenic per bee has been found to be a lethal dose. When arsenical sprays alone are applied to trees, particularly if to the open blossom as is sometimes the case with gooseberries and cherries, severe poisoning from the pollen may be expected. On the other hand, much of the danger from contaminated water should be removed by the incorporation of lime sulphur (1% or more) or nicotine sulphate (0.05% nicotine) into sprays intended for application either before flowering or after petal fall, provided that alternative sources of water are available for foraging bees. Provision of water within the hive is suggested as a further safeguard.
Black scurf and stem canker of potato (Corticium Solani Bourd. & Galz.)
Authors: Ph.D. T. Small 
Published: February 2008

Black scurf and stem canker of the potato was investigated in field trials on infected soil at Warburton, Cheshire, to study the effect of planting clean and contaminated seed, and the relation between the dates of planting and lifting and the contamination of the crop tubers.Black scurf was prevalent on crops grown from clean seed but was more severe on crops raised from contaminated seed. Under conditions favourable for the disease the yields from clean and contaminated seed were satisfactory and were not significantly different. Young shoots of plants from contaminated seed were severely attacked and tuber formation was checked; these results were not obtained on clean seed plots.More black scurf occurred on late‐dug crops; on early‐dug plots the disease, although almost absent in 1941, was prevalent in 1942. Late planting failed to reduce appreciably the amount of black scurf.Variety trials included Arran Banner, Kerr's Pink (two vigorous varieties), King Edward and Majestic (two less vigorous varieties). All were heavily infected and each recovered well from an attack on the young shoots.Inoculation of the seed at planting time did not affect the results; in all trials, misses and wilted shoots caused by Corticium were rare and there was no relation between the yield and the amount of black scurf on the crop tubers.The results indicate that the disease causes little, if any, loss under farm conditions.
The preparation of a standard pyrethrum extract in heavy mineral oil, with observations on the relative toxicities of the pyrethrins in oil and aqueous media
Authors: Martin J. T. 
Published: February 2008

The preparation of a pyrethrum extract in highly refined heavy mineral oil, suitable for use as a basis of reference in the biological evaluation of commercial pyrethrum‐heavy oil preparations, is described. The solution was standardized with respect to colour, resin content and equal proportions of the pyrethrins. A standard solution containing pyrocatechol remained stable, when judged by the chemical determination of the pyrethrins, over a period of months.When applied in a heavy mineral oil medium, pyrethrin II was shown to possess a toxicity to Tribolium castaneum Hbst. approaching, if not equal to, that of pyrethrin 1. When applied in an aqueous medium the toxicity of pyrethrin II was very much lower than that of pyrethrin I.
The natural cross‐pollination of crop plants with particular reference to the radish
Authors: Crane M.B. , Mather K. 
Published: February 2008

Experiments were carried out to determine what degree of intervarietal cross‐pollination occurs when two radish varieties are grown at varying distances apart. The varieties chosen were Icicle and Scarlet Globe. Hybrids are distinctive; thus crossing is readily determined.In closely planted experiments, where one half of the plot was Icicle and the other half Scarlet Globe, the amount of intercrossing ranged from 30 to 40 % at a distance of 9 in. to an average of about 1 % at 15 ft. Intercrossing decreased fairly regularly and rapidly with distance.Single plants of Icicle were run out from plots of Scarlet Globe; in 1941 at distances from 9 in. to 95 ft. and in 1942 from 9 in. to 408 ft. In the plants near the red plots crossing was approximately 100 %. In 1941 there was a regular and rapid fall with distance and intervarietal crossing stopped at 95 ft. In 1942 the plots were closer to beehives; intercrossing was less regular and extended farther than in 1941, but beyond 240 ft. it was only 0.1%, and in an all‐white plot 360 ft. from a red plot with no intervening stringer plants it was nil.Given a mass of plants and a profusion of flowers, bees confine their flower visiting to a small area. When radishes are grown in quantity 300 ft. guards against contamination of stock due to intervarietal crossing. If only small numbers are grown intercrossing is likely to occur over a greater distance.