bluuebunny/crossref_metadata_2025 huggingface dataset:
Reviews
Authors: BROWN W.
Published: February 2008

Vistas in Botany. Edited by W. B. Turrill

Practical Botany for the Tropics. By W. O. Howarth and L. G. G. Warne

Perspectives in Virology. Edited by M. Pollard

Progress in Biochemistry since 1949. By F. Haurowitz

Biochemistry of Antibiotics (Edited by K. H. Spitzy and R. Brunner), and Biochemistry of Morphogenesis (Edited by W. J. Nickerson)

Cell, Organism and Milieu. (17th Symposium of the Society for the Study of Development and Growth, 1958.) Edited by D. Rudnick

A Symposium on Molecular Biology, 1956–7. Edited by R. E. Zirkle

Plant Nematology. Edited by J. F. Southey

Plant Growth Substances. By L. J. Audus

Müller, P. (general editor): DDT, the Insecticide Dichloro‐Diphenyltrichloroethane and its Significance. Vol. 1. Ed. by Paul Müller

Müller, P. (general editor): DDT, the Insecticide Dichloro‐Diphenyltrichloroethane and its Significance. Vol. 11. Ed. by S. W. Simmons

Statistical Methods in Biology. By N. T. J. Bailey.

Elementary Statistics, with Applications in Medicine and the Biological Sciences. By F. E. Croxton

Subcellular Particles. (5th Annual Symposium publication of the Society of General Physiologists in America.) Edited by Teru Hayashi

Comparative morphology of Vascular Plants. By Adriance S. Foster and Ernest M. Gifford, Jr., 555

Breeding Field Crops. By J. M. Poehlman

Rice. By J. H. Grist (3rd edition)

Principles of General Physiology. Vol. 1: The Physico‐Chemical Background. By L. E. Bayliss.

Evolution of Nervous Control from Primitive Organisms to Man. Edited by Allan D. Bass

The Principles of Humane Experimental Technique. By W. M. S. Russell and R. L. Burch

Photoperiodism and Related Phenomena in Plants and Animals. Editor Robert B. Withrow

The Scientific Principles of Crop Protection. By Hubert Martin

British Parasitic Fungi. By W. C. Moore

Blakeslee: the genus Datura. By A. G. Avery, S. Satina and J. Rietsema
EFFECT OF CULTURAL TREATMENTS ON THE INCIDENCE OF STRIGA HERMONTHICA (DEL.) BENTH. AND YIELDS OF SORGHUM IN THE SUDAN: FIELD EXPERIMENTS 1957/8
Authors: LAST F. T.
Published: February 2008

Trap cropping, nitrogenous fertilizers, selective weed‐killer sprays (2:4‐D) and sorghum varieties affected the incidence of Striga hermonthica.

S. hermonthica developed more on the variety Debekri than Feterita. Usually, applying increasing amounts of nitrogen (sulphate of ammonia or urea) progressively decreased the incidence of S. hermonthica on Feterita, Dwarf White Milo and Wad Fahl. Early applications were more effective than late applications. Nitrogen given to Debekri never significantly decreased the amount of S. hermonthica and often increased it.

In an experiment on very infertile and heavily infested soil, nitrogen increased the amounts of S. hermonthica on all varieties but less on Feterita than Debekri. The weights of S. hermonthica on Feterita reached a maximum with 40 lb. N/acre but were still increasing after adding 80 lb. N to Debekri.

Weed‐killer sprays affected S. hermonthica on Feterita and Debekri equally. They delayed the appearance of its aerial stems and usually decreased their subsequent growth. Spraying with 1.6 lb. 2:4‐D/acre was usually more effective than with 0.8 lb. and sometimes spraying 3 weeks after sowing was better than after 2 weeks.

Trap cropping with Sudan grass (Sorghum sudanense) for 5 weeks, but not for 3, significantly decreased the incidence of S. hermonthica in succeeding sorghum crops and sometimes increased grain yields.

Phosphorus and potassium affected neither the incidence of S. hermonthica nor sorghum yields. On lightly infested soil where S. hermonthica was not damaging, 80 lb. N/acre trebled grain yields (from 1140 to 3530 lb./acre). As infestations increased in severity, the absolute gains decreased but the relative effects were greater. On crops infected early and severely, yields increased by 820% from 180 to 1505 lb./acre. Nitrogen applied at sowing and after 3 weeks gave larger increases than later applications.

Yield increases caused by 2:4‐D sprays are associated with the delayed emergence of aerial stems of S. hermonthica. Where infection developed rapidly and the mean levels of infection were at least 20% within 50 days of sowing, sprays increased both grain and straw yields; where infection developed slowly, only grain yields were increased. Although 1.6 lb. of 2:4‐D/acre decreased S. hermonthica more than 0.8 lb., they affected yields equally as did spraying 2 or 3 weeks after sowing.

0.8 lb. of 2:4‐D/acre and 80 lb. N/acre when applied separately to severely infected crops increased grain yields from 38 lb. in the untreated plots to only 163 and 588 lb./acre respectively, whereas applied together they gave 2170 lb./acre. In the same experiment nitrogen increased the yields of the less heavily infected Feterita more than those of Debekri. 2:4‐D affected both varieties similarly.
THE EFFECTS OF THE SIZE, POSITION AND MATURATION PERIOD OF INFLORESCENCES AND FRUITS ON ABNORMAL PIGMENTATION IN THE TOMATO VARIETY POTENTATE
Authors: COOPER A. J.
Published: February 2008

A modification to an earlier classification of pigmentation abnormalities, enabling it to be used for varieties other than Potentate, is discussed. It is shown for Potentate that the proportion of fruits giving uniform ripening colour declines with increasing fruit weight, while the proportion of Grade C fruits steadily increases. The occurrence of Grade A fruits, however, is maximal in fruits of 80 to 120 g. The occurrence of pigmentation abnormalities was shown to be independent of the length of the maturation period of the fruit. It was found that Grade A fruits occurred with greater frequency in fruits developing on upper inflorescences, while Grade C fruits occurred more frequently on lower inflorescences. The number of fruits in an inflorescence was shown to have no consistent relation to pigmentation abnormalities, nor was there any relation between pigmentation and the position of fruits within the inflorescence. Frequent examples of an antithetic relation between the occurrence of Grades A and C symptoms are noted, suggesting that conditions that are favourable for the development of the one are unfavourable for the development of the other.
DIDYMELLA STEM‐ROT OF OUTDOOR TOMATOES
Authors: FISHER) DOROTHY E. KNIGHT (NÉE , KEYWORTH W. G.
Published: February 2008

In studies on Didymella stem‐rot of outdoor tomatoes several possible modes of introduction of the disease were investigated, together with methods of avoiding them. The pathogen was found to invest and penetrate the seeds in diseased fruit without destroying their viability and methods were devised of ridding the seeds of infection. It was not, however, possible to demonstrate the infection of mature plants from infected seed. It was found that the disease could be introduced on contaminated canes, in potting soil and from plant debris from the previous season's crop. The spread of the disease was encouraged by overhead irrigation.

Tests of strains of various species of Lycopersicon showed that one line of L. hirsutum was highly resistant to stem and root infection although another line was highly susceptible.
ANTIFUNGAL ACTION OF STREPTOMYCIN‐COPPER CHELATE AGAINST PHYTOPHTHORA INFESTANS ON TOMATO (LYCOPERSICON ESCULENTUM)
Authors: CROSSE R. , McWILLIAM R. , RHODES A. , DUNN A. T.
Published: February 2008

The antifungal protection afforded by streptomycin‐copper chelate in vivo in greenhouse tests against Phytophthora infestans on tomato was found to be of the order of six times greater than that of streptomycin sulphate. The copper chelate also showed much greater resistance to simulated rainfall. Similar tests showed that streptomycin‐copper chelate (in terms of streptomycin content) was from 2 1/2 to 5 times more effective as an antifungal prophylactic spray than zinc ethylene‐bis(dithiocarbamate) (zineb), and some fifty times more active than copper oxychloride formulated as a commercial 50% wettable powder. These three materials showed roughly similar resistance to weathering by ‘rainfall’ and it was assumed therefore that 250 i.u./ml. streptomycin as streptomycin‐copper chelate might be expected to give the same degree of protection against Phytophthora infestans in the field as would the usual field rates of usage of zineb and copper oxychloride.
STUDIES ONGLOEOSPORIUM MUSARUMCKE. & MASSEE CAUSING STORAGE ROTS OF JAMAICAN BANANAS
Authors: MEREDITH D. S.
Published: February 2008

A form of anthracnose, caused byGloeosporium musarumCke. & Massee, is responsible for appreciable wastage of Jamaican Lacatan bananas. Symptoms are often evident on immature fruit after 8–10 days storage in refrigerated ships' holds. On green fruit, lesions are characteristically lenticular, having a slightly sunken, dark centre and an orange‐yellow border: they rapidly increase in size as the fruits approach maturity. The fungus readily infects small scratches on the skin and, in inoculation experiments, resulted in the development of lenticular lesions after 8–10 days storage at 55° F. Many observations suggest that naturally occurring infections often originate at small abrasions acquired during handling of fruit.

On the basis of histological findings, it is proposed to refer to lenticular lesions as ‘non‐latent anthracnose’, thus distinguishing this form of infection from the ‘latent’ type described by earlier workers.

In several experiments the antifungal antibiotic nystatin, applied as a post‐inoculation fruit‐dip at concentrations of 200 and 400 p.p.m., effected good control of wound‐infection byG. musarum.Percentage control was inversely related to the incubation period between inoculation and treatment, there being little or no control with periods exceeding about 30 hr.
THE BIOLOGICAL CONTROL OF THE WATTLE BAGWORM, KOTOCHALIA JUNODI (HEYL.), BY A VIRUS DISEASE
Authors: OSSOWSKI L. L. J.
Published: February 2008

To obtain further information about the effect of virus on wattle bagworm and on the course of an infestation cycle, suspensions of various concentrations and different origins were tested in 1957 against both young and old larvae. Virus of suspected low virulence and suspensions with and without adjuvants were also compared.

With infestations in the prodromal stage and the larvae in their first instar at the time of treatment, mortality was similar with suspensions containing 1000 or 500 polyhedra/mm.3. Mortality was less with 250 polyhedra/mm.3, but still high enough to keep the crowns of the infested trees green. With the higher concentrations, the course of the cycle was greatly accelerated and the eruptive stage and the crisis occurred later in the same season, whereas, with the lowest concentration, the infestation decreased gradually after spraying. Against older larvae, the initial mortality was too low to prevent defoliation, but 9 months after spraying the mortality had increased sufficiently to reduce the infestation to its latent stage.

Where virus was applied during the eruptive stage, there was a very high initial mortality, and defoliation of trees was light, whereas untreated trees were completely defoliated. Nine months after spraying, however, mortality was equally high in treated and untreated plantations.

Viruses from different sources differed considerably in the mortality they caused. Virus introduced from a distant source was more effective than local strains, and at the prodromal stage was more successful in preventing defoliation and loss of yield.

Methyl cellulose, used as a sticker, did not affect mortality, but skim‐milk powder decreased it.

Artificially disseminated virus can not only cause epizootics in the treated plantations, but can also spread to neighbouring blocks in the years following treatment.
INSECTICIDAL CONTROL OF PAEDOGENETIC CECID LARVAE IN MUSHROOM BEDS
Authors: HUSSEY N. W. , WYATT I. J.
Published: February 2008

Aldrin and γ‐BHC, at concentrations above 10 p.p.m., were shown to be promising materials in experiments on the prevention of sporophore contamination by cecid larvae, following the incorporation of insecticides in the casing before its application to the beds.
THE EFFECTS OF TEMPERATURE AND HUMIDITY ON THE RATE OF DEVELOPMENT AND THE MORTALITY OF TRIBOLIUM CONFUSUM DUVAL (COLEOPTERA, TENEBRIONIDAE)
Authors: HOWE R. W.
Published: February 2008

The speed of development and the developmental mortality of Tribolium confusum were studied over a series of constant temperatures between 15° and 40° C. at 10, 30, 70 and 90% R.H. using wheatfeed as food.

Eggs did not hatch at 15° or 40° C. at any humidity. At 37.5° C. about 60% of eggs hatched and at all other conditions about 90% hatched. The effect of temperature on the duration of the egg period is shown graphically, the shortest period being at 35° C. Humidity does not affect the egg period.

Larvae failed to develop to pupae at 17.5° C., at 10% R.H. at 20° C, and at 10 and 90% R.H. at 37.5° C. The rate of larval development was affected by both temperature and humidity being quickest at the higher humidities and at about 32.5° C. Larval mortality was less than 16% except at 37.5° C., at 10% R.H. or less, and at 20°C., 90% R.H.

The duration of the pupal period was not affected by humidity and was shortest at 37.5°C. The total developmental period is compared with that of T. castaneum over the range of temperature and humidity conditions in which both species can grow. The optimum for developmental speed and the maximum and the minimum temperatures at which development is possible were all about 2.5°C. lower for T. confusum than for T. castaneum. The developmental periods for the two species were equal at temperatures between 23 and 27°C., depending on humidity. At lower temperatures, T. confusum developed the more quickly and at higher temperatures the more slowly.
INFECTIVITY OF APHIDS BRED ON VIRUS‐INFECTED CAULIFLOWER PLANTS
Authors: BROADBENT L.
Published: February 2008

Caged cauliflower plants infected with either cabbage black ring spot virus (CBRSV) or cauliflower mosaic virus (CIMV) were colonized with Myzus persicae or Brevicoryne brassicae. Winged and wingless aphids that voluntarily flew or walked from these plants were transferred singly to healthy cauliflower or other brassica seedlings to compare their feeding behaviour and ability to transmit the viruses. Wingless aphids settled to probe more readily than winged, and B. brassicae was initially more restless than M. persicae. CIMV was more readily transmitted than CBRSV by both species, and B. brassicae rarely transmitted CBRSV. Wingless aphids transmitted less often than winged ones, and no wingless B. brassicae transmitted CBRSV, although they did CIMV. Fewer aphids transmitted CBRSV from old plants than from young ones, but plant age had little effect on CIMV transmission.
THE EPIDEMIOLOGY OF PHYTOPHTHORA INFESTANS
Authors: HIRST J. M. , STEDMAN O. J.
Published: February 2008

Of 3260 blighted tubers planted as seed in 5 successive years (1954‐8), twenty‐one produced stems invaded from below ground by Phytophthora infestans (0.79 and 0.52% respectively of those infected artificially and naturally). Only in 1955 was no stem found to be invaded, in every other year they started epidemics in experimental plots. On average the first stem lesions were found 62 days after planting and 38 days before blight outbreak became general in the district.

There was evidence of two patterns of dispersal for P. infestans. Distant spread was probably by air‐borne sporangia, but that near to the initial sources probably resulted from sporangia transported in water. The effects of initial sources of infection on the date when the disease became general could not be traced for more than a few hundred yards. Blight often reached crops remote from the experiments at the same time as it infected every plant within them; this often happened during the weather which elicited disease forecasts.

Under certain conditions of soil moisture, P. infestans from artificially infected tubers planted as seed seemed able to pass through the soil to infect leaves near it and to start epidemics without invading stems from below ground. Attacks originating in this way developed similarly to those started by invaded stems, but their importance and the conditions limiting their occurrence have yet to be determined.
METABOLISM OF PLANT GROWTH REGULATORS
Authors: LUCKWILL L. C. , LLOYD‐JONES C. P.
Published: February 2008

Comparison of the metabolism of 14C carboxyl‐labelled 2,4‐D in detached leaves of different varieties of apple showed that the 2,4‐D‐resistant Cox decarboxylated 57% of the 2,4‐D in the leaf in 92 hr., whereas the susceptible Bramley's Seedling decarboxylated only 2% in the same time. Comparatively high rates of decarboxylation were found with all varieties of apple having Cox in their parentage; varieties unrelated to Cox showed low rates of decarboxylation. Similar high rates of decarboxylation were found in resistant varieties of strawberry and in Syringa vulgaris. Sixteen other species tested showed low rates of decarboxylation, irrespective of whether they were resistant or susceptible to 2,4‐D.

The rate of decarboxylation of 2,4‐D in the mature strawberry leaf was proportional to the amount of 2,4‐D in the leaf. The rapid fall in decarboxylation rate in a detached leaf was due chiefly to reduction in the amount of 2,4‐D present, and not to any falling off in the metabolic activity of the leaf. Young leaves decarboxylated 2,4‐D at about half the rate of fully grown or senescent leaves. Oxidation of the methylene carbon proceeds at less than half the rate of that of the carboxyl carbon and is accompanied by an increase in the phenol content of the leaf which agrees closely with the amount of 2,4‐D demethylated.

As previously reported for currants, part of the 2,4‐D entering the leaf was bound and part inactivated by the formation of water‐soluble compounds. The reaction of strawberry variety Talisman to 2,4,5‐trichlorophenoxyacetic (2,4,5), 2‐chloro‐phenoxyacetic (2‐CPA), 4‐chlorophenoxyacetic (4‐CPA) and 2‐methyl‐4‐chlorophenoxyacetic (MCPA) acids was similar to that previously reported for red currant. Leaves of Cox's Orange Pippin apple and Talisman strawberry were able to decarboxylate all these phenoxy‐acids except 2‐CPA.
AN ATTEMPT TO INHIBIT THE MULTIPLICATION OF TOBACCO MOSAIC VIRUS IN TISSUE CULTURE BY ITS ANTISERUM
Authors: MICZYNSKI K. A.
Published: February 2008

Extracts from tobacco tissue cultures infected with tobacco mosaic virus grown in medium containing antiserum to the virus had only one‐half to one‐sixteenth as much virus as extracts from tissues grown in medium without the antiserum. When tissues grown with antiserum were thoroughly washed before they were extracted, the extracts contained as much virus as extracts of tissues grown without antiserum. The antiserum did not affect virus multiplication, but antibodies in the tissues may have precipitated virus either in the cells or when the tissues were macerated.
SOME EFFECTS OF TEMPERATURE AND OF VIRUS INHIBITORS ON INFECTION OF FRENCH‐BEAN LEAVES BY RED CLOVER MOTTLE VIRUS
Authors: SINHA R. C.
Published: February 2008

Keeping French‐bean plants before inoculation at 36, 32 or 28°C. for 1–2 days increased their susceptibility to infection with red clover mottle virus, but longer exposures to 36 and 32°C. decreased susceptibility. Susceptibility increased most rapidly at 36°C. The number of infections was unaffected by changes in post‐inoculation temperatures between 12 and 24°C., but decreased above 24°C. The rate virus multiplied increased with increase of temperature up to 28°C., but the maximum virus concentrations reached at 18, 24 and 28°C. were very similar and above the maximum reached at 30°C.

Thiouracil inhibited infection slightly but neither it nor azaguanine affected the multiplication of red clover mottle virus in French bean. Trichothecin inhibited infection and interfered with virus accumulation. Inhibition of infection was associated with macroscopic injury to the leaves, and washing leaves up to 1 hr. after inoculation prevented both inhibition and leaf damage. Virus multiplication was not resumed when leaves were transferred from trichothecin solutions to water.
VARIETAL RESISTANCE OF LETTUCE TO ATTACK BY THE LETTUCE ROOT APHID, PEMPHIGUS BURSARIUS (L.)
Authors: DUNN J. A.
Published: February 2008

Striking varietal differences in susceptibility to attack by the lettuce root aphid, Pemphigus bursarius L., were first found in lettuces grown at Wellesbourne in 1955. Subsequent work has confirmed that White Favourite and Imperials E‐4 and 19551‐M are highly resistant; Imperial 45634‐M, Continuity and Iceberg are markedly resistant. Midas, Salad Bowl and Imperial 4164 each appear to be a mixture of susceptible and resistant plants.

Immigrant winged forms of P. bursarius showed no preference for colonizing any particular variety of lettuce, and it seems that resistance to attack results from antibiosis.

It is suggested that varietal differences in the composition of root sap may account for the differences in susceptibility to lettuce root aphid, but analyses of water and alcohol extracts of root sap from resistant and susceptible lettuce varieties have not shown consistent differences.
BREAKING THE REST PERIOD IN BLACK CURRANTS WITH GIBBERELLIC ACID AND LOW TEMPERATURE
Authors: MODLIBOWSKA IRENA
Published: February 2008

A single application of gibberellic acid (GA) was successful in breaking the rest period of black currants in September, October and November, while chilling for 2 weeks was insufficient to be effective.

The highest percentage of bud burst was obtained by GA application immediately after defoliation. Delay in GA application after defoliation decreased and delayed plant response because penetration of GA was hindered. Multiple and very early GA applications immediately after taking the plants into the glasshouse caused shedding of undeveloped buds.
BROWN ROOT ROT OF TOMATOES
Authors: EBBEN M. H.
Published: February 2008

Population counts and nutritional grouping of bacteria from a tomato‐sick soil showed that steaming greatly reduced the population and the percentage of group I bacteria (i.e. those able to use inorganic nitrogen). The numbers subsequently increased, and by the time tomatoes were planted, the distribution of nutritional groups approximated to that in unsteamed soil. Rhizosphere and root‐surface population numbers did not differ widely in steamed and unsteamed soils. The nutritional groups in soil before planting differed much more between samples from steamed soil with a changing population, than from soil unsteamed for 3 years. Groups I and II (bacteria requiring amino acids) were higher in unsteamed, cropped soil than in steamed soil, and were dominant in rhizosphere and root‐surface populations. Group I increased on the root surface in unsteamed soil from July to October, whereas group II increased on root surfaces in steamed soil. Group V (bacteria requiring soil extract) was less frequent on the root surface than in soil from plots unsteamed for 1 year, but more frequent on the root surface than in soil unsteamed for 3 years.
PYRETHRUM CULTIVATION IN ENGLAND, 1925‐37
Authors: MARTIN J. T.
Published: February 2008

Small plot and field experiments on the cultivation of the insecticidal pyrethrum plant in England during 1925‐37 showed that the plant grew well and produced satisfactory yields of flowers of high pyrethrin content: costings of the field trials, however, showed that the cultivation of the plant was uneconomic. Individual plants grown from seed differed considerably in growth habit and in the pyrethrin content of their flowers.
Determination of the resistance of locusts to γ‐BHC and diazinon in relation to their age, sex and weight
Authors: MacCUAIG R. D.
Published: February 2008

The relation between body weight and resistance to γ‐BHC and diazinon was studied in experiments using the desert locust (Schistocerca gregaria) and the African migratory locust (Locusta migratoria migratorioides).

In all experiments with Schistocerca, resistance was proportional to weight within any one age and sex group. Resistance to diazinon (per unit body weight) decreased with age, that of the males at a faster rate than that of the females. Against γ‐BHC the insects showed a nearly twofold increase in resistance about 1 week after fledging.

Within groups of Locusta the resistance to diazinon was found to be independent of weight, but the resistance to γ‐BHC was dependent on weight. Similarly the resistance to diazinon at different ages after fledging was independent of age but resistance to γ‐BHC increased with age.
Effect of time and temperature on toxicity of insecticides to insects
Authors: DAS M. , NEEDHAM P. H.
Published: February 2008

The effects of a change in temperature (15–28° C.) on the toxicity of dilute suspensions of DDT to larvae of Aédes aegypti L., as assessed by a photomigration method, depended on the stage of the test during which the temperature was changed. Increase in temperature during exposure to DDT (0.02 p.p.m. for about 1 hr.) increased the toxic action. When larvae were left in the suspensions for the duration of the test (3 hr.‐4 days), increase in temperature throughout the test decreased the toxic action of a very low concentration of DDT (0.002 p.p.m.), but had no effect with higher concentrations (0.1–0.2 p.p.m.). Toxic action was greater in larvae held at a low temperature than in larvae held at a high temperature after treatment (0.025 p.p.m. for 3 hr.). Such toxic action was reversible: a change from high to low temperature increased paralysis, and larvae, paralysed at a low temperature, recovered when the temperature was raised.
Effect of time and temperature on toxicity of insecticides to insects
Authors: DAS M.
Published: February 2008

The toxicity of DDT to insects usually increases as the post‐treatment temperature is decreased in the commonly used temperature range (30‐10° C.). The toxicity increased further when the post‐treatment temperature of adult Tenebrio molitor L., dosed by topical application, was decreased from 10 to 6° C. However, when the post‐treatment temperature was decreased still more (down to — 1° C.), the toxicity by topical application or by injection apparently decreased again. The size of this ‘positive temperature coefficient’ below 6° C. decreased as time passed after treatment. Differences in toxicity below 6° C. were more apparent than real, and were the result of differences in the speeds at which symptoms appeared.

The slight toxic action at very low temperatures was evidently not caused by failure of DDT to penetrate the cuticle, or to reach its site of action. More probably, the speed of the chemical or physical process which actually caused paralysis was extremely low at the very low temperatures.
The relationships between increased oxygen uptake and locomotor ataxy or death in insecticide‐poisoned Alphitobius laevigatus F
Authors: GOSTICK K. G.
Published: February 2008

The relationships between increased oxygen uptake and locomotor ataxy or death induced by LD50's of n‐valone (2‐n‐valeryl‐1,3‐indandione), γ‐BHC, p,p'‐DDT, dieldrin, DNBP (2,4‐dinitro‐6‐sec.‐butylphenol), malathion and allethrin, in individual lesser mealworm beetles (Alphitobius laevigatus F.) have been investigated. n‐Valone did not increase the rate of oxygen uptake of treated beetles. After dosage with DDT or malathion, increased oxygen uptake occurred only in beetles which were knocked down and beetles knocked down always died. After dieldrin treatment, increased oxygen uptake was always associated with knock‐down, but a few knockeddown beetles recovered. γ‐BHC, allethrin or DNBP caused knock‐down or serious locomotor ataxy and increased oxygen uptake in all the treated beetles, but those which eventually died reached higher peaks in rate of oxygen uptake. The similarities and differences between the effects of the various insecticides are discussed together with some aspects of their possible mode of action.
Fluctuations in the aerial density of Anisopus fenestralis Scop. (Diptera) above sewage bacteria beds
Authors: HAWKES H. A.
Published: February 2008

Using a standard 9 in. diameter disc‐dropping suction trap, the aerial density of Anisopus fenestralis above bacteria beds was assessed hourly on 410 24‐hourly occasions over a period of 19 months, and the prevailing temperatures and wind velocities were recorded. Between o and 10 m.p.h. wind velocity there was a gradual rise in catch associated with a rise in temperature to an optimum, beyond which the catch decreased. This optimum fell as wind velocities rose; it occurred between 70° and 75° F. at winds between 2 and 4 m.p.h., at 65–70° F. with winds between 4 and 6 m.p.h. and at 60–65° F. between 6 and 8 m.p.h. At all temperatures between 30 and 80° F. the catch fell as wind velocity increased from o to 10 m.p.h. By comparing the dusk catches on successive days a significant positive correlation was found between the deviation in log catch from a 3‐day running mean and the corresponding temperature deviation, except when the wind velocity deviation exceeded + 2. There was also a significant negative correlation between deviation in log catch from the running mean and the corresponding deviation in wind velocity, except when the temperature deviation exceeded — 2.

The average regressions showed that for each °F. rise in temperature the log catch was raised by 0.14 and for each 1 m.p.h. rise in wind velocity the log catch was decreased by 0.19. Expressed arithmetically the catch was doubled by a 2.2° F. rise in temperature or by a fall in wind velocity of approximately 1.5 m.p.h.

The aerial density was affected not only by weather but also by fluctuations in the A. fenestralis population within the bed arising from direct and indirect climatic effects on its food supply—the microbial growths within the bed. Lower winter temperatures favour an accumulation of food, so the patterns of seasonal incidence of the flies from year to year are affected by the severity of the preceding winter.
Experiments on the value of stupefying and lethal substances in the control of harmful birds
Authors: RIDPATH M. G. , THEARLE R. J. P. , McCOWAN D. , JONES F. J. S.
Published: February 2008

Laboratory experiments and field trials in town and country were carried out with four reputedly narcotic substances (pentobarbital sodium, dithiobiuret, tri‐orthocresyl phosphate and chloralose) and four poisons (picrotoxin, nicotine, parathion and sodium fluoroacetate) to investigate their value in the control of pigeons, corvids and sparrows.

The alpha isomer of chloralose was the most satisfactory material tested; it normally produces narcosis from 15 to 30 min. after ingestion on wheat or maize and this lasts from 10 to 20 hr. Its potency was assessed using treated grain, gelatine capsules and flour pills, administered with and without food, and also from field data. It was most effective on grain and least effective in gelatine capsules. The flour pill method was the most satisfactory for obtaining an LD 50 figure which for alpha‐chloralose used against feral pigeons was about 131 mg./kg. live weight. The pure beta isomer of chloralose was ineffective.

Using alpha‐chloralose, urban populations of feral pigeons were reduced from 48 to 83% in three to seven treatments. In fifty‐two trials in towns 1544 feral pigeons were disabled, only five of the 1409 picked up being found at a greater distance than 500 yards from the baiting point. With five different concentrations between 2.5 and 0.5% by weight in bait, the lower concentrations produced lower mortality without affecting the size of the catch. Bait containing chloralose at 1.5% by weight gave the greatest efficiency with a mortality of less than 50% and this concentration is recommended for practical control operations.

In towns the risk of accidentally affecting legally protected species is negligible, whereas in rural districts it is much higher, at any rate when grain baits are used. The use of maize greatly reduces the risk to small birds which cannot swallow the large grains.

Four series of field trials in Kent and East Anglia in autumn and winter caught only seven wood‐pigeons and one stock‐dove during a total of 72 baiting days. This disregard for cereals is discussed and is thought to be due to changing ‘feeding images’.

In four field trials to catch corvids, using alpha‐chloralose on maize, only fourteen were narcotized. Two field trials using alpha‐chloralose against house‐sparrows were unsuccessful, but eighty house‐sparrows were captured incidentally during four of the trials on feral pigeons. With the possible exception of nicotine none of the other substances tested showed promise for controlling birds. The use of blue‐coloured baits, as a warning to the public, reduced takes by feral pigeons but did not prevent feeding altogether.

The value of alpha‐chloralose as a control agent and the hazards it presents to wildlife are discussed; its use probably offers a better means of controlling feral pigeons in towns than any existing method.
Verticillium wilt of tomatoes—the role of pectic and cellulolytic enzymes
Authors: WOOD R. K. S.
Published: February 2008

An isolate of Verticillium albo‐atrum, highly pathogenic to tomato plants, secreted polygalacturonase (PG) on a variety of synthetic media. Particularly active filtrates were obtained from cultures on media containing mineral salts, casamino acids and pectin or polypectate. Pectates were degraded more rapidly than pectin. None of the filtrates had high cellulase or pectinesterase activity; the most active were from cultures with carboxymethyl cellulose or pectin as carbon sources.

The fungus made little growth in exudates from xylem sap unless carbon sources were added, and then culture filtrates had appreciable PG and cellulase activity but very little pectinesterase activity. Saps from susceptible and resistant varieties gave similar results.

The fungus was also grown on a synthetic sap based upon an analysis of xylem exudate. Results similar to those for xylem sap were obtained.

Filtrates from cultures on dead stems of both varieties had little pectinesterase activity and a definite but relatively low PG and cellulase activity.

Extracts from diseased plants had no PG or cellulase activity but had a considerably higher pectinesterase activity on fresh and dry weight bases. Exudates from xylem of diseased plants had no PG or cellulase activity but had a low pectinesterase activity which was slightly higher than that from healthy plants.

The effects of different culture filtrates on cuttings is described. Filtrates with high PG activity produced some of the symptoms found in naturally diseased plants.

Solutions of pectin, polypectate and carboxymethyl cellulose caused cuttings to wilt in very low concentrations; much higher concentrations were needed after solutions of these substances had been degraded by PG or cellulase.
Studies on silvering disease of red beet
Authors: KEYWORTH W. G. , HOWELL J. SHEILA
Published: February 2008

Observations and experiments were made on silvering disease of red beet during the period 1952–59. The disease is most prevalent on seed crops of the variety Cheltenham Green Top, but also affects other cultivars of Beta vulgaris, often only mildly. The causal organism is Corynebacterium betae sp.nov. which can be found in the tap‐roots, stems and leaves of systemically affected plants causing veinal or uniform silvering of the leaves followed by wilting and death of the plant. External leaf infection gives rise to silvered lesions on the laminae or leaf margins.

About 1% of the seeds from infected plants contain the pathogen and these seeds give rise to plants showing systemic symptoms. The bacteria spread from such plants in the seedling bed during the autumn and winter, probably entering other plants through their leaf edges. Such spread can occur to distances of at least 50 yards, and the planted out seed crop may be up to 75% infected. The disease is readily transmitted on knives which have cut infected roots.

Seed treatment with streptomycin or erythromycin (200–400 g/ml.) gives almost complete control of the disease. Mercurial dusts are less effective but have been found of some value in practice.
Investigations on fungitoxic derivatives of salicylaldehyde
Authors: SMITH R. J. , READ W. H.
Published: February 2008

A number of halogenated derivatives of salicylideneaniline were synthesized, several of which showed high eradicative activity against cucumber powdery mildew when sprayed on to young pot plants. The two most promising compounds were 3‐bromo‐and 3‐chloro‐salicylideneaniline. These were subjected to commercial‐scale trial, but, although more effective (at 0.08–0.10%) than standard 2:4‐dinitro‐6‐(1‐methyl‐heptyl)phenyl crotonate (‘Karathane’) sprays in controlling severe mildew infection, they showed phytotoxic effects on mature cucumber plants.

Their toxicity to certain other fungi is outlined in the appendix.
Effect of nitrogen supply on the response of Majestic potato to gibberellic acid
Authors: HUMPHRIES E. C. , FRENCH S. A. W.
Published: February 2008

Potato plants sprayed with gibberellic acid (GA) were given extra nitrogen either through the soil (as ammonium nitrate) or through the leaves (as urea). GA increased the initial production of dry matter but the effect did not persist, even with additional N. The number of leaves on lateral branches was decreased by GA partly because leaf production on laterals at lower nodes was inhibited. N increased the rate leaves were produced on lateral branches; the soil application doubled the leaf number and the urea increased it by 50%. GA, but not N, increased the area of a main‐stem or lateral‐stem leaf; however, nitrogen produced the largest total leaf area because it produced more leaves. There was no evidence for any interaction between GA and N either in the effect on leaf number or total leaf area. The fall in total N content per unit area caused by GA found in an earlier experiment was confirmed and additional N did not arrest this decline. Loss of efficiency of GA‐sprayed plants is unlikely to result from indirect deficiency caused by rapid leaf expansion.
Some isolates of virus causing swollen‐shoot disease of cacao in Nigeria and their interrelationships
Authors: THRESH J. M.
Published: February 2008

Many symptomatically distinct virus isolates were made from cacao trees infected with swollen‐shoot disease in Nigeria. The symptoms caused by typical viruses from six different localities were studied on seedling Amelonado cacao inoculated as beans. Two isolates caused swellings as the only permanent symptom and another caused only leaf chlorosis. The others caused both swellings and chloroses of different type and severity. Two atypical isolates were much less virulent than the others and caused only transient and very inconspicuous leaf symptoms.

Isolates from the same or from adjacent trees usually protected against each other, whereas those from dissimilar areas did not. This suggests that the isolates are not all closely related and they may be grouped according to the results of plant protection tests.
Witchweed (Striga hermonthica) on rain‐grown pearl millet in nitrogen‐deficient sandy soil of the central Sudan
Authors: TARR S. A. J.
Published: February 2008

Spraying with 1 lb./acre of 80% sodium 2,4‐D 2 weeks after sowing reduced incidence of the phanerogamic root parasite Striga hermonthica (Scrophulariaceae, ‘witchweed’) attacking rain‐grown pearl millet (Pennisetum typhoides) in sandy soil of the Central Sudan, but this control resulted in increased yields only on land very deficient in available nitrogen and not when ammonium sulphate fertilizer was added. Nitrogen deficiency may be more important than Striga attack in limiting yields of millet in these sandy soils, although in inherently fertile clay soils elsewhere in the Central Sudan Striga has been reported to cause heavy crop losses to sorghum (Sorghum vulgare) before signs of soil exhaustion appear.
The growth requirements of Phoma violacea, with reference to its disfiguration of painted surfaces
Authors: EVELEIGH D. E.
Published: February 2008

Growth requirements of Phoma violacea in comparison with the commoner paint‐attacking fungi Pullularia pullulans and Cladosporium herbarum were determined. In liquid culture media, growth occurred over a range of pH values from 3 to 8, double optimal pH values being noted. A wide range of carbohydrates supported good growth. Lipolysis was not marked. Phoma violacea strains were autotrophic for vitamins. Zinc oxide exhibited fungistatic properties at 5% in agar medium, but was not fungicidal. White lead caused slight fungistasis while titanium dioxide had no marked effect on fungal growth.
Effects of time and temperature on the fungistatic action of mercury‐containing and other compounds on conidia of Botrytis fabae Sardiña
Authors: McINTOSH A. H.
Published: February 2008

The in vitro fungistatic action of nineteen compounds was measured on conidia of two strains of Botrytis fabae Sardiña in slide‐germination tests, at two or three incubation temperatures in the range 10–25° C.; the effects were assessed at intervals up to 14 days from the start of each test.

In general, the ED 50's increased as incubation time passed, finally approaching or reaching steady values. With each compound, an increase in incubation temperature increased the speed of action (i.e. decreased the time taken for the ED 50 to reach a steady value), and increased the ultimate toxicity. Temperature coefficients were calculated as ratios of ED 50's and were ‘positive’ or ‘negative’ according to whether the toxic action was greater or less at the higher temperature.

The conidia of the two strains of B. fabae behaved similarly, but the temperature coefficients were larger with one strain (A) than the other (B).

Mercuric cyanide, chloride, bromide, acetate and thiocyanate gave positive coefficients which increased in size as incubation time passed. In these tests, which lasted for only 3 days, the largest 10:25° C. coefficient (+ 35) was given by the cyanide after 3 days (strain A); the corresponding figures for the chloride and bromide were + 10.5 and +6.0. Phenyl mercury acetate, methyl mercury nitrile, silver nitrate, copper sulphate, 8‐hydroxyquinoline, acetamide, p‐nitrophenol, 2,4‐dinitrophenol and pentachlorophenol gave coefficients which were usually small and positive (about + 1.3), and changed only slightly in size as incubation time passed. t‐Butyl alcohol, pyridine, 3‐picoline, phenol and p‐chlorophenol gave coefficients which changed from negative (‐ 3.9 to ‐1.5) to positive (+1.3 to +3.2) after 2–7 days (strain B).

There was little evidence that spores are more resistant to fungicides at their optimum temperature for germination, i.e. the temperature at which maximum germination is reached soonest (15–20° C. for B. fabae).

Mercuric cyanide, chloride and bromide, which are scarcely ionized in aqueous solution, also resembled non‐electrolytes in that the sizes of their positive temperature coefficients were inversely related to their solvent: water partition coefficients, i.e. the temperature coefficients increased with decrease in the presumed rates at which lipoid membranes are penetrated by diffusion. This correlation did not extend to other compounds.
Strains of Botrytis allii resistant to chlorinated nitrobenzenes
Authors: PRIEST D. , WOOD R. K. S.
Published: February 2008

When Botrytis allii was grown in nutrient agar in the presence of vapour of penta‐chloronitrobenzene (PCNB), or isomers of tetrachloronitrobenzene (TCNB), a slow‐growing mycelium of distorted hyphae was produced on which sporulation was much reduced or suppressed. After periods which differed with the different fungicides, variants were produced which in the absence of fungicide closely resembled the parent but which, in the presence of fungicide, grew much more rapidly than the parent, and produced hyphae of normal appearance. A strain produced in response to one fungicide was more resistant than the parent to each of the other three fungicides, but the extent of this resistance depended on the origin of the strain. The most resistant was the 2,3,4,6‐TCNB‐resistant strain, followed in turn by the 2,3,5,6‐TCNB‐, 2,3,4,5‐TCNB‐, and PCNB‐resistant strains.

In liquid culture, apart from the fact that fungistatic effects were less pronounced, the results were similar to those obtained on agar; the resistant strains utilized carbohydrate more efficiently than did the parent strain in the presence of each of the fungicides.

The strains resistant to PCNB and TCNB were also resistant, in varying degrees, to diiodo‐, dibromo‐ and dichloronitrobenzenes. The diiodo‐ and dibromo‐ compounds were less active against B. allii than was TCNB, whereas the dichloro‐ compounds were more active and in certain conditions killed inocula. Resistant strains were also resistant to benzene, to 2,3,5,6‐tetrachloronitroaniline, and to 2,6‐dichloro‐4‐nitro‐aniline, the active principle of ‘Allisan’. Resistant strains retained their resistance for at least 18 months under ordinary conditions of laboratory subculturing, and were as pathogenic to onions as was the parent strain.
The effect of gibberellic acid on the incidence of loose smut of wheat
Authors: MANTLE P. G.
Published: February 2008

Under greenhouse and field conditions gibberellic acid treatment did not significantly affect the development of loose smut mycelium within a susceptible wheat plant. No control of the disease occurred; on the contrary, the results suggested an increased fungal growth following treatment under certain greenhouse conditions.
The poison baiting of corn‐ricks with particular reference to the control of house‐mice
Authors: ROWE F. P. , TAYLOR E. J. , CHUDLEY A. H. J.
Published: February 2008

Experimental warfarin treatments designed to reduce house‐mouse (Mus musculus) and common rat (Rattus norvegicus) populations in corn‐ricks are described. Baiting rick bases at permanent poison points or in rat holes was found not to be completely successful in controlling either rats or mice. Bait placed 1 ft. inside ricks in containers or wrapped in paper was effective in reducing the level of mouse infestation. In ricks treated after erection, baits wrapped in paper were more easily applied.

Samples of threshed grain taken from each sack showed that ricks baited internally contained fewer mouse droppings but more poison bait residues than ricks baited at ground level only.
The effect of paracrinkle virus on the growth of King Edward potato at different temperatures and daylengths
Authors: KASSANIS B. , SCHWABE W. W.
Published: February 2008

The growth of King Edward potatoes of a stock freed from paracrinkle virus was slightly but consistently superior to that of an infected stock, when grown in controlled environments. Although the leaves of the infected plants showed no evident symptoms, their lower water content suggested incipient N‐deficiency. Changes in daylength and night temperature affected virus‐free and infected plants similarly. Long days and high night temperature decreased tuber formation, and the higher tuber and total dry weights in short days probably resulted from increased leaf area and reduced stem growth.