bluuebunny/crossref_metadata_2025 huggingface dataset:
Problems in assessing insecticidal control of Amnemus species (Coleoptera. Curculionidae) in clover pastures of north coastal New South Wales
Authors: Braithwaite B. M. , Jane Annette
Published: July 2009

Results are presented of 15 experiments made in north coastal districts of New South Wales from 1957 to 1961 with insecticides against the weevils Amnemus quadrituberculatus (Boh.) and A. superciliaris (Pasc.), the larvae of which have been reported as pests attacking the roots of clover (Trifolium repents, T. pratense and T. subterraneum) there. The adults live above ground, and single surface applications of insecticides were made to pastures in the form of dusts, granules or dilutions of emulsifiable concentrates in January, when maximum numbers of weevils were present and before significant oviposition had taken place. Insecticidal control was assessed by soil sampling for larvae in July–August, during the following winter. Pasture cuts were made in an attempt to assess the effect of treatments on the yield of clover.

Dieldrin at rates of 2 and 4 lb. per acre gave near eradication of Amnemus for one year, and satisfactory control was obtained with 1 lb. per acre. Aldrin, endosulfan (Thiodan) and BHC were less effective, and limited tests with heptachlor suggested that it was inferior to dieldrin. The scanty results available suggest that dieldrin is effective against Amnemus for only one year, but it is doubtful if annual applications are warranted. Owing to the patchy distribution of clover in the pastures, only one experiment showed an increased yield of clover associated with the reduction in numbers of larvae of Amnemus brought about by the application of 1 lb. dieldrin per acre. Similarly, poor persistence of clover on all plots prevented assessment of any residual effect on yield in the second year.

No method was found by which accurate estimates could be made of the density and distribution of adults of Amnemus in pastures to which insecticides were to be applied. Treatments, therefore, were replicated more frequently than was needed statistically in order to ensure that measurable levels of larval infestation were present at sufficient sites.

Small plots (500–700 sq. ft.) proved of little value, and this is attributed not only to contamination of control plots but possibly also to the death of weevils that moved from untreated into treated plots. Large plots (13,000–21,000 sq. ft.) gave the most consistent results in assessment of insecticides.

Control of Amnemus did not increase the productivity or persistence of clover, and it is concluded that any benefits from control are unlikely to be significant unless other factors, such as competition from grasses, drought, floods, nematodes and diseases of clover, which affected the density and persistence of clover in these experiments, are not limiting.
Toxicology and genetics of two types of insecticide resistance in Chrysomyia Putoria (Wied.)
Authors: Busvine J. R. , Bell J. D. , Guneidy A. M.
Published: July 2009

Resistant and normal colonies of the blowfly Chrysomyia putoria (Wied.) were obtained from the Congo and cultured in London. By selection and inbreeding, sub-colonies homogeneous for resistance to (a) the BHC/dieldrin group of chlorinated insecticides and (b) malathion, were obtained. Homogeneous resistant colonies were markedly less fertile and were difficult to perpetuate.

Toxicological investigations of the BHC/dieldrin-resistant colony revealed a characteristic resistance spectrum similar to that of six other insect species. Genetical experiments with the BHC/dieldrin-resistant strain indicated inheritance by a single gene pair, intermediate in dominance, very similar to that reported in nine other insect species.

Toxicological investigations of the malathion-resistant colony, including tests with 19 organophosphorus insecticides, showed a resistance largely specific to malathion and malaoxon. This was rather similar to malathion-resistant strains of two other species, for which data were available. It is known that the toxic action of malathion on mammals can be potentiated by prior treatment with small doses of certain organophosphorus compounds, which inhibit an aliesterase that detoxifies malathion by carboxylic hydrolysis, and furthermore that potentiation has been found in malathion-resistant strains of the house-fly, Musca domestica L. Accordingly, the phenomenon was investigated in C. putoria by adding non-lethal amounts of EPN or tri-o-cresyl phosphate (TOCP) to malathion. It was found that specific malathion-resistance was virtually abolished by this means, a result that suggests that such resistance in this species depends on a carboxyesterase. Genetical experiments with the malathion-resistant strain indicated inheritance by a single gene pair, with nearly complete dominance, similar to that in three other insect species.

It is concluded that both types of resistance in C. putoria have much in common with those occurring in analogous strains of other insect species.
Cattle-tick control in Northern Nigeria: a field study of BHC, Sevin, toxaphene and ronnel used as sprays
Authors: Thorpe R. J. , Walker P.
Published: July 2009

A field study was made of the effects of γ BHC, Sevin, toxaphene and ronnel (fenchlorphos) used as sprays on the numbers of ticks infesting cattle at Shika stockfarm in the Northern Guinea Savannah zone of Nigeria.

The tick population included Boophilus annulatus (Say), B. decoloratus (Koch), Amblyomma variegatum (F.), Hyalomma truncatum Koch and Rhipiccphalus simus simus Koch, and its distribution on the host is described.

Significance tests of treatment difference were carried out for initial kill and reinfestation rate. In both dry- and wet-season trials toxaphene proved to be the most effective ixodicide. A satisfactory degree of control was given by γ BHC but not by Sevin or ronnel.

It is concluded that spraying at 21- and 7-day intervals during the dry and wet seasons, respectively, with either toxaphene or γ BHC will maintain a stable, satisfactory level of tick parasitism and premunity to tick-borne diseases in the herd.
The biology of Cryptolestes pusilloides (Steel & Howe) (Coleoptera, Cucujidae), a pest of stored cereals in the Southern Hemisphere
Authors: Lefkovitch L. P.
Published: July 2009

Cryptolestes pusilloides (Steel & Howe) has, since 1944, become a regularly occurring pest of stored cereals in South America, Australia, South Africa, and to a lesser extent, East Africa, and apparently occurs also in North America as well as in Portugal (where it has recently been found on stored almonds), but has not established itself in flour mills in the U.K., notwithstanding its frequent introduction. Prior to that time it appears to have been very rare. Its life-cycle resembles that of C. ugandae Steel & Howe, and in common with that species and with C. turcicus (Grouv.), it is unable to breed successfully at relative humidities below 50 per cent. Its temperature range is 15–35°C., the optimum for development and fecundity being at about 30°C. at 90 per cent. R.H. Survival was greatest at 27·5°C. and newly formed adults weighed most at 22·5°C. In general, males weighed more than females and their developmental period under any one set of conditions was slightly longer than that of females. The biological information now available shows that C. ferrugineus (Steph.) and C. capensis (Waltl), which are taxonomieally associated by exhibiting sexual dimorphism in the structure of the mandibles, are species that can withstand dry conditions, whereas C. ugandae, C. turcicus, C. pusillus (Schönh.) and C. pusilloides, all of which show sexual dimorphism in the antennae, are unable to breed at relative humidities much below 50 per cent.
The control of the sources of virus yellows of sugar-beet
Authors: Ribbands C. R.
Published: July 2009

The means whereby sugar-beet yellows viruses and their predominant vector,Myzus persicac(Sulz.), overwinter in Britain are reviewed.M. persicaeoverwinters mainly on cultivated secondary host plants that are not associated with the viruses: the viruses overwinter principally in the mangold and sugar-beet seed crops, which are the main source of infection in the following summer; mangold clamps may be a minor source and weeds seem unimportant.

Despite autumn certification of first-year sugar-beet seed crops, visible infection within them in the following June is never negligible, and rapid spread of virus within these crops during their second year can cause a high proportion of the plants therein to be infective, although still symptomless. The many aphids that may leave these crops and the uncertified seed crops are an important source of infection for the root crop.

It is suggested as a new control measure that seed crops of beet and mangolds should be grown in Britain in alternate years only. Consideration of the low frequencies of winds of a speed and direction suitable for carrying viruliferous aphids from Continental beet-growing areas to Britain, and of the low incidence of virus yellows in areas of Britain that are free of seed crops and comparable, in distance and direction relative to the main British beet-growing areas, with those of the latter in relation to the Continent, suggests that the effectiveness of the proposed measure is unlikely to be nullified by intrusion of infected aphids from the Continent.
Laboratory studies on dispersion behaviour of adult beetles in grain. IV.—The lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera, Bostrychidae)
Authors: Surtees Gordon
Published: July 2009

Dispersion behaviour of the adult of the lesser grain borer, Rhyzopertlia dominica (F.), was investigated under controlled conditions by observing the numbers occurring on the surface, or at various depths below it, in small bulks of grain. The effects of population density, temperature and moisture content of the grain on numbers at the surface were studied by using groups of insects in 500 g. wheat, and on dispersion in the vertical plane by confining beetles within a monogranular plate of wheat held between vertical glass sheets, through which the positions of individuals could be observed.

In grain at 25°C. and 14 per cent, moisture content (70 per cent. R.H.), the proportion of a group on the surface averaged approximately six per cent, for densities of 5–100 insects in 500 g., and the proportion was higher than in grain at the same temperature and 9 or 17 per cent, moisture, or at the same moisture content and 15 or 35°C.

In grain of 14 per cent, moisture content, the level of individual locomotory activity increased from 15 to 35°C. At 25°C., locomotory activity was depressed in grain of 9 and 14 as compared with 17 per cent, moisture content. These results are discussed in relation to group formation and dispersal of R. dominica and its contact with Sitophilus granarius (L.) if both species are present in the same grain bulk.
Biology and ecology of the garden chafer,Phyllopertha horticola(L.). VIII.—Temperature and larval growth
Authors: Laughlin Roger
Published: July 2009

Fecundity in the garden chafer,phyllopertha horticola(L.), is extremely variable. Fecundity depends entirely on reserves laid down by the larva.

Previous work in Britain showed that (a) early larval feeding periods in the field produce heavy pupae; (b) in an experiment comparing early with late-hatched larvae, the heavier diapause larvae developed from the early batch; (c) in the field, the earliest larvae to enter diapause were the heaviest.

Further data (hitherto unpublished) showed that larvae reared at 25°C. entered diapause heavier than larvae reared at field temperature, although mortality was high. The above data also indicated that time of entry into diapause was fixed and unaffected by temperature.

A repeat of the field experiment (b) showed the same result and also showed how a population of feeding third-instar larvae can be destroyed by frost while larvae in diapause deeper in the soil are unaffected. Thus a late season produces light larvae and a high risk of death before diapause.

Observations on larvae kept at constant temperatures (12, 16 and 18°C.) showed that the temperature threshold of development is about 12°C. in the first instar but is lower in succeeding stages; the length of the first and the second instars decreases with rise in temperature; high temperature probably produces larger larvae by the end of the second instar, but the effect was small and none at all was detected at the first moult.

The length of the third-instar feeding period is not affected by temperature in the range 12–20°C. Kate of growth (increase in weight) increases with temperature. The higher temperatures (perhaps as a result) produce heavy diapause larvae and pupae in both sexes. Entry into diapause is hindered at 20°C. The weight of a larva at the second moult is positively correlated with its diapause weight.

It is suggested that the temperature effects described can be most simply explained by postulating the existence of differential temperature coefficients for the various growth processes.
Insecticidal activity and structure of some organotin compounds
Authors: Gardiner B. G. , Poller R. C.
Published: July 2009

The insecticidal activities of 13 triphenyltin compounds having the general formula (C6H5)3Sn X were compared with those of other organotin compounds and DDT by exposing adults ofSitophilus oryzae(L.) for 48 hours on filter paper impregnated with 1 per cent, solutions of the compounds in benzene, and by allowing larvae ofTineola bisselliella(Humm.) to feed for 14 days on pieces of woollen cloth impregnated with 1 per cent, by weight of the compounds. The triphenyltin compounds were ineffective as contact insecticides, virtually all theSitophilusadults surviving, whereas all were killed by DDT. Their effectiveness as stomach poisons varied with the nature of the Group X, mortality after 14 days amongst theTineolalarvae ranging from 76 per cent., for triphenyltin thiophenoxide, down to zero, for hexaphenylditin. All except the latter and triphenyltin sulphide were highly effective moth-proofing agents, the weight lost by the test pieces being less than 5 per cent, of that lost by the untreated control. Tetraphenyltin afforded no protection againstTineola, but tributyltin oxide caused 100 per cent, mortality, apparently by contact action, since none of the test piece was eaten.
Laboratory assessment of the toxicity of field-weathered deposits of insecticides to larvae of the codling moth, Cydia pomonella (L.)
Authors: Gratwick M.
Published: July 2009

The toxicity of naturally weathered deposits of 21 chemicals to larvae of the codling moth, Cydia pomonella (L.), was assessed by spraying apple trees in the orchard and testing samples of the fruit picked at various intervals after treatment. Each apple was placed in a separate glass container with one first-instar larva from a laboratory culture, and larval mortality and damage to the fruit (defined as removal of a portion of the skin) were recorded after three days in a constant environment.

The site of entry of the larvae was shown to vary with fruit size, calyx entries decreasing and side entries increasing with increase in the surface area of the fruit.

The relationship between larvicidal activity and age of the spray deposit for periods up to ten weeks after spraying is illustrated graphically; data are presented for fruit damage caused by larvae applied one and three weeks after spraying.

On the basis of larval mortality and fruit damage recorded in tests on deposits up to three weeks after application, a spray containing 0·1 per cent, carbaryl was the most effective, followed by 0·05 per cent, fenthion, while Bayer 5024, Zectran, DDT, DDD (all at 0·l per cent.) and 0·04 per cent, azinphos (as the methyl or ethyl homologue) were only slightly less effective. Deposits from 0·1 per cent. Kepone, 0·02 per cent, diazinon, 0·11 per cent, malathion, 0·01 per cent, parathion and 0·05 per cent, carbophenothion, dimethoate and ethion also caused 90–100 per cent, mortality when fresh, but were less persistent. Fresh deposits from 0·1 per cent, endosulfan, 0·04 per cent, dioxathion, 0·05 per cent, phenkapton, 0·02 per cent, phosphamidon, 0·2 per cent, lead arsenate and 0·6 per cent, ryania only killed 50–88 per cent, of the larvae, and their residual toxicity was proportionately low.

Heavy rain soon after spraying caused a large reduction in deposits from wettable powders but the accompanying reduction in larvicidal activity was shown to be greater in the case of carbaryl than for DDT or DDD.
On the biology and taxonomy of some European species of the genus Elachertus Spinola (Hymenoptera, Eulophidae)
Authors: Askew R. R.
Published: July 2009

A key is given for the separation of a group of allied species of Eulophidae comprising Elachertus nigritulus (Zett.), E. geniculatus (Eatz.), E. olivaceus (Thoms.), E. scobiciae Erdős, and a species here described as E. pallidus sp. n. Biological data for each species are given. E. nigritulus and E. geniculatus have previously been regarded as synonymous; the latter parasitises Laspeyresia strobilella (L.), a pest of conifers, whereas E. nigritulus, and also E. pallidus, attacks Lepidoptera associated with fruit trees.
Blaesoxipha filipjevi Rohd. (Diptera, Sarcophagidae) parasitising Zonogerus variegatus (L.) (Orthoptera, Acridoidea) in Nigeria
Authors: Taylor T. Ajibola
Published: July 2009

Adults of Zonocerus variegatus (L.) collected in southern Nigeria in January to May 1963 were found to be parasitised by larvae of Blaesoxipha filipjevi Rohd. Of 1,691 adults of Z. variegatus dissected, 43 contained from one to six larvae of B. filipjevi, but none was found in 167 nymphs dissected mostly in January and February. No parasites were found in 155 examples of 11 other locally occurring species of Orthoptera. Full-grown larva left their hosts through the cervical membrane; they pupated within 48 hours, probably in the soil in natural conditions, and the adult Sarcophagid emerged 9–10 days later. No larva was observed to undergo diapause. The presence of the parasite restricted the ovarian development of the female host, but the species is considered to be of negligible importance in the control of Z. variegatus because of its low incidence.
The growth of restricted populations of Lasioderma serricorne (F.) (Coleoptera, Anobiidae)
Authors: Lefkovitch L. P.
Published: July 2009

Two types of population history shown by Lasioderma serricorne (F.) are described, one when the food was renewed at regular intervals, the other when there was no food renewal. Initially, both of these populations increased together to a high level, the former continuing at this level until the observations were discontinued, the latter declining and eventually becoming extinct. Stage-specific properties, which relate the numbers in each stage to those a unit of time previously and which are functions of the survival, developmental and fecundity rates, were estimated for each type of population; they are compared as between the two types and with the corresponding properties of a population given effectively unlimited space and food. It is shown that the effect of the limiting conditions produced a decrease in survival, developmental and fecundity rates. From this, together with other evidence, it appears that food shortage, not space shortage, was the primary cause. After the initial increase in numbers, the stage-specific properties shown by the species in both populations imply that there was a regular oscillation in the developmental, survival or fecundity rates, which would result in corresponding fluctuations in numbers.
Insect reinfestation problems in fumigated maize on the Kenya coast
Authors: Ashman F.
Published: July 2009

Bagged maize stored in large stacks on the Kenya coast is subject to reinvasion by stored-products pests following successful fumigation with methylbromide, and treatment of the stack surfaces with insecticidal sprays has been unsatisfactory in preventing reinfestation.

Further tests are described of different methods of applying insecticides to small experimental stacks, each composed of ten 200-lb. bags of maize, exposed within a warehouse, after fumigation, to reinfestation from a large bulk of maize heavily infested with Tribolium castaneum (Hbst.). Populations of adults and pre-adult stages of T. castaneum were recorded from samples of grain obtained by a sampling spear from each bag at intervals.

In the first of two experiments, single applications of malathion in a spray at 100 and 150 mg. per sq. ft. to the entire external surface of each bag during the construction of the stack did not give good control of reinfestation in the six months after fumigation, but were not significantly worse, respectively, than a dust containing 1 per cent. lindane similarly applied to the upper surface of each bag and, four weeks later, to the outside of the stack at the rates of 3 and 6 oz. per bag. When the malathion treatments were followed by 24, 12 or 8 applications, at intervals of 1, 2 or 3 weeks, respectively, of sprays containing malathion to give 100 and 150 mg. per sq. ft. over the whole external surface of the stack, good control of T. castaneum was obtained with all treatments.

Mean residues of malathion in the outer inch of maize in the bags six months after the start of the experiment varied from 3 to about 19 p.p.m., according to treatment, suggesting that little penetrated through the bag wall and that after thorough mixing of the grain before use the malathion content would not exceed the permissible limit.

In the second experiment, an admixture of malathion dust with the maize before bagging to give 8 p.p.m. active ingredient gave almost complete control of larvae and pupae, and application of 3 oz. 0·5 per cent, malathion dust, or a spray affording 400 mg. malathion per sq. ft., to the upper surface of each bag during stacking gave highly significant reductions in numbers of T. castaneum in the pre-adult stages. The last of these treatments, followed, after fumigation, by malathion applied in a spray at 150 mg. per sq. ft. every three weeks to the external surfaces of the stack, is recommended for large-scale trial.
Studies on the responses of the femaleAedes Mosquito. X.—Comparison of oestrogens and amino acids as attractants
Authors: Roessler P. , Brown A. W. A.
Published: July 2009

The attractiveness of oestriol and of a sample L-lysine to females ofAedes aegypti(L.) was tested (a) in an olfactometer of the Wieting-Hoskins type, and (b) in a free-flight cage enclosed in glass. Similar results were given by both methods, L-lysine being the more attractive at higher concentrations, but oestriol retaining its attractiveness down to much lower concentrations. When 27 L-amino acids were tested in the free-flight cage, 16 showed significantly positive stimulation. Of these lysine was the most attractive, representing a group of 11 which carried CO2in carbaminoyl or adsorbed form or in both; the other five, of which tyrosine was the most attractive, carried no CO2.
Genetical studies on dieldrin-resistance in Musca domestica L. and Lucilia cuprina (Wied.)
Authors: Guneidy A. M. , Busvine J. R.
Published: July 2009

The mode of inheritance of dieldrin-resistance in house-flies, Musca domestica L., was investigated by crossing experiments, using a selected, inbred resistant colony (R) and a normally susceptible one (N). Levels of susceptibility in both colonies and in various hybrids derived from them were determined by treating batches of flies with different concentrations of dieldrin by topical application.

Reciprocal crosses gave closely similar results, which were pooled. Results obtained with males and females were analogous, but were treated separately. The F1 hybrids were intermediate in resistance and the F2 generation segregated into susceptible, hybrid and resistant individuals in the ratio 1:2:1. The F1 generation back-crossed to either parental strain gave 1:1 segregation, corresponding to NN + NR or NR + RR. After killing the more dieldrin-susceptible forms in each case, the remaining males were back-crossed again. The second back-cross to normal gave a further 1:1 segregation of susceptibles and hybrids. The second back-cross to resistant now gave all homozygous resistant forms.

These results strongly indicate monofactorial inheritance.

Two highly dieldrin-resistant colonies of the sheep blowfly Lucilia cuprina (Wied.) had been colonised, one from Australia and one from South Africa. These were crossed and the progeny maintained to the F2 generation. Tests with dieldrin on the F1 and F2 generations gave results resembling those obtained with the parents. Since there was no appearance of susceptible or hybrid forms in the F2, it is concluded that the genes in the two colonies occur on the same chromosome and are either allelic (possibly identical) or very closely linked.
A dipping technique for selecting house-flies, Musca domestica L., for resistance to insecticides
Authors: Sawicki R. M. , Farnham A. W.
Published: July 2009

A dipping technique for exposing large numbers of house-flies (Musca domestica L.) to measured doses of insecticide is described. It is suitable for selecting resistant populations and, while giving consistent results, is more rapid than other techniques used for this purpose.

Up to 2,000 flies of both sexes, less than 24 hr. old, are immersed for three minutes in 100 ml. of a 70 per cent, mixture of acetone and water containing the required concentration of insecticide, using a 9-cm. sintered glass Büchner funnel as the immersion chamber. The liquid is then removed by suction, the sides of the funnel are wiped with filter paper, and the flies are allowed to drain for three minutes; they are then transferred in small batches to plastic recovery chambers containing food. Mortality is recorded next day, and the survivors are released into breeding cages.

Experiments showed that immersion for three minutes in 70 per cent, acetone was virtually harmless to the flies and that the amount of insecticide deposited on individual flies was reasonably uniform (coefficient of variation about 20%). Batches of 2,000 flies, but not more, could be treated at one time.

When the dipping technique was compared with topical application of measured drops of insecticide, using a susceptible strain of house-flies and two other strains that were resistant to DDT and diazinon, dipping gave steeper log-probit regression lines than topical application, and the LD50's and resistance factors of the resistant strains were smaller. With flies resistant to DDT, dipping gave straight regression lines whereas topical application gave compound lines.
A preliminary assessment of the effectiveness of pyrethrum against the stalk borer, Busseola fusca (Fuller) in the field in Kenya
Authors: Weaving A. J. S.
Published: July 2009

Five trials were conducted in Kenya in 1962–63 to investigate the effectiveness of a 0·2 per cent, w/w pyrethrum dust, synergised with 5 parts piperonyl butoxide to 1 part pyrethrins, against the stalk borer Busseola fusca (Fuller) by applying it to maize at 20 lb. per acre. In three trials, it was compared with a dust containing 5 per cent. DDT applied at the same rate. Pyrethrum showed an efficiency in controlling B. fusca equal to that of DDT. Both insecticides produced reductions of more than 50 per cent, in the incidence of infestation, and in the final trial there was a significant reduction of over 40 per cent, in the number of cobs damaged by stalk-borer larvae; at the same time, an increase in yield was apparent. Further work is required in order to determine the lowest effective concentration of pyrethrins in the dust, which is likely to be less than 0·2 per cent., and to indicate the best time of application.
The occurrence of two strains ofBrontispa longissima(Gestro) (Col., Hispidae) based on resistance or non-resistance to the parasiteTetrastichus brontispae(Ferrière) (Hym., Eulophidae) in Java
Authors: Tjien-Mo Tjoa
Published: July 2009

In Java,Brontispa longissima(Gestro) (Col., Hispidae) is represented by chr. var.javanaWeise and in South Sulawesi (South Celebes) by chr. var.selebensisGestro. The endoparasiteTetrastichus brontispae(Ferriére) (Hym., Eulophidae) attacks both chr. var.javanaandselebensis.However, in Java, there are two distinct strains of chr. var.javana. In one strain (A-strain) the parasite completes its development normally but in the other (B-strain) the parasites usually die in the larval stage. The areas where each strain occurs have been demarcated.

In laboratory studies at Bogor during 1958 it was established that the lifecycles of the A- and B-strains were similar.T. brontispaecompleted its development from egg to adult in 15 to 21 days (16 on average) in A-hosts but died in the larval stage in B-hosts within three to four days. In a few instances parasites in B-hosts were able to complete their development, but generally the host died a few days after the death of the parasites.

In the laboratory, adult parasites attacked B-hosts as readily as A-hosts, although the former were not suitable for parasite development. Phagocytosis by encapsulation or melanisation was occasionally encountered but was not the usual cause of the death of the parasites.
Method of attachment of pupae of Mansonia annulifera (Theo.) and M. uniformis (Theo.) to Pistia stratiotes
Authors: Burton George J.
Published: July 2009

Detailed studies are described, and illustrated by photomicrographs, of the method by which the newly emerged pupae of Mansonia annulifera (Theo.) and M. uniformis (Theo.), which are important vectors of filariasis in Kerala State, India, attach themselves to the aquatic plant Pistia stratiotes. After emergence of the cephalothorax through the ruptured larval skin, the latter continues to support the pupal abdomen while this doubles over so that the respiratory trumpets of the cephalothorax are directed towards and eventually reach the point of insertion of the larval siphon into the Pistia root. The trumpets are then plunged into the hole occupied by the larval siphon, which is almost simultaneously yanked out of it by the straightening of the pupal abdomen, leaving the pupa attached by its trumpets. The pupa casts off the larval skin posteriorly and then curls round to assume the usual comma shape. The entire process occupies under one minute in M. annulifera and 3–6 minutes in M. uniformis.
Similarity in response to diazinon, dieldrin and pyrethrum extract by allatectomised and normal house-flies (Musca domesticaL.)
Authors: Sawicki R. M.
Published: July 2009

Allatectomy of newly emerged house-flies (Musca domesticaL.) prevents maturation of the ovaries, and experiments were done to find whether this affected the sensitivity of the flies to insecticides.

The apparatus and operational procedure for removing the complex comprising the corpus allatum and corpora cardiaca are described.

Females of a diazinon-resistant strain (SKA) were allatectomised less than 12 hr. after emergence, and when three days old their sensitivity to diazinon, dieldrin and pyrethrum extract was tested by topical application. Approximately equal numbers of intact females were tested simultaneously, and untreated controls of both kinds of flies were included in every test. The failure of the ovaries to mature in allatectomised flies was confirmed by examination of a majority of the operated flies that lived for four days, and normal development of the ovaries of intact flies was similarly confirmed.

The results showed that there was no difference in sensitivity between allatectomised and normal flies. It is concluded that allatectomy does not affect susceptibility to the insecticides used. Since earlier work had shown that a 9- to 18-fold increase in resistance to diazinon takes place during the period from emergence to the third day afterwards, it is further concluded that this increase is unaffected by allatectomy and the failure of the ovaries to mature.
Laboratory analysis of oviposition behaviour in the red locust,Nomadacris septemfasciata(Serv.)
Authors: Woodrow D. F.
Published: July 2009

Gravid females of the red locust,Nomadacris septemlasciata(Serv.), were initially influenced by the microclimate in the selection of oviposition sites, and a laboratory investigation showed that females preferred to lay in well-illuminated areas with a soil temperature between 43 and 37°C., and avoided areas of very high surface humidity. Final acceptance of the soil took place only after the locust had probed with its ovipositor, and experiments demonstrated that particle size, compaction, moisture content and chemical composition of the soil all influenced the choice of oviposition site, while pH did not.
Morphology of the immature stages of Meligethes aeneus (F.) and M. viridescens (F.) (Coleoptera, Nitidulidae)
Authors: Osborne P.
Published: July 2009

Experimental evidence is given to show that only two larval instars occur during the development of Meligethes aeneus (F.) (Coleoptera, Nitidulidae) under laboratory conditions in Scotland, based on the facts that there is only one moult and only one increase in head-capsule width. The egg, first- and second-instar larvae, prepupa and pupa of M. aeneus are described and compared with the corresponding stages of M. viridescens (F.). The larvae of the two species are differentiated for the first time by the arrangement of dorsal cuticular tubercles, the size and form of the urogomphi and the width of the head capsules.
Observations on the bionomics of Laspeyresia ptychora Meyr. (Lepidoptera, Eucosmidae) infesting cowpea in Nigeria
Authors: Taylor T. Ajibola
Published: July 2009

One of the principal pests of cowpea (Vigna unguiculata) in southern Nigeria is Laspeyresia ptychora Meyr., the larvae of which attack the seeds within mature pods and cause considerable loss of yield. It has not so far been recorded from northern Nigeria. Details of the life-history of this Eucosmid are described from laboratory and field observations made in Nigeria in 1962–63. Eggs are laid on mature pods, which the larvae enter very soon after hatching, feeding on the seeds within. Pupation normally takes place in a cocoon in the soil, but pupal development can be completed in the absence of soil and of a cocoon. Four generations normally occur on the two crops of cowpea that can be grown each year in southern Nigeria, a complete first and a partial or complete second generation on each; but five generations may sometimes occur. The pest survives through the dry season and between the two crops in the rainy season by means of generations that develop on stand-over and volunteer cowpea, on leguminous plants grown in market gardens, and possibly on some yet undiscovered wild plant. No diapause in any stage was observed.

Annual fluctuations in larval populations and levels of infestation are described in relation to the cowpea crops and to the damage caused. In a field trial in 1963, 35 per cent, (by weight) of seed from the early crop and 20 per cent, of that from the late crop was damaged. These figures take no account of seed that was completely destroyed, so that the true losses are greater than they indicate. Damaged seed is usually unmarketable as a result of contamination with frass and webbing.

Investigations showed that, although larvae may be carried into stores when the crop is harvested, L. ptychora cannot become a pest of stored cowpea seeds because it is unable to develop on dried seeds.

The possibilities of chemical, cultural and biological control are discussed, the latter not at present being promising. Field trials with γ BHC, dieldrin, carbaryl, isobenzan and phosphamidon were carried out; only the last-named, which is a systemic insecticide, showed promise of affording satisfactory control. The difficulties of successfully attacking L. ptychora with insecticides are discussed, and it is concluded that chemical measures will need the support of modified cultural practices, particularly those directed towards destruction of stand-over and volunteer cowpea plants, if a satisfactory level of control is to be achieved.
Life-cycle of the tropical warehouse moth,Cadra cautella(Wlk.), at controlled temperatures and humidities
Authors: Burges H. D. , Haskins K. P. F.
Published: July 2009

The life-cycle of five stocks ofCadra cautella(Wlk.) (Phycitidae) and the duration of the various developmental stages were studied at temperatures from 15 to 37·5°C. and relative humidities between 0 and 100 per cent, on a mixture of wheatfeed, wheat germ and yeast. At 70 per cent. R.H., the limiting temperatures for the completion of the life-cycle were about 15°C. and about 36°C. At 30°C., the limiting humidities were about 20 and above 90 per cent. R.H. Development was quickest at 30–32°C. and 70–80 per cent. R.H., taking 29–30 days from the laying of the egg to the formation of the adult moth. This period increased with lower temperature and humidity, reaching 145·0 days at 15·5°C. (70 per cent. R.H.) and 51 days at 20 per cent. R.H. (30°C.).

Near the optimal conditions for rapid development, the egg occupied about 10 per cent, of the developmental cycle, the larva about 70 per cent, and the pupa 20.

Temperature influenced the duration of all developmental stages, but humidity had a marked effect only on the larva. The pupation of some mature larvae was delayed: whether or not this delay is a diapause is discussed. Virgin adults lived 4·8 days at 35°C. to 18·9 days at 17·5°C. (70 per cent. R.H.). At 30°C., low humidity halved the length of adult life.

The mortality, even in favourable conditions, was often rather high, principally among eggs and young larvae.

There was poor survival of small numbers of larvae kept on maize and on cocoa beans, but survival on wheat was similar to that on the usual food mixture. The developmental period on wheatfeed alone was shortened by the addition of honey or glycerine or a combination of wheat germ and yeast.

The incidence of disease is discussed.
Investigations of the chemical control of insect pests of cotton in central Africa. III.—Field trials
Authors: Matthews G. A.
Published: July 2009

Field trials in 1958–62 at Gatooma Research Station, Rhodesia, in which carbaryl, DDT, endrin and endosulfan were compared for controlb of insect pests of cotton, confirmed earlier laboratory results which showed that larvae of Diparopsis castanea Hmps. were more susceptible to carbaryl than those Heliothis armigera (Hb.) but that the latter were more susceptible to DDT. Counts of larvel populations showed that neither insecticide used alone could control the bollworm complex statisfactorily. The results indicated that optimum control could best be achieved by applying one or other insecticide as appropriate after inspection of the crop to determine the level of insects attack at diffetent stages during the seasons, rather than by use of mixtures of both insecticides. It is recommended that dimethoate should be added to either of the insecticides for aphid and red spider mite control when required.
A new species of Neospastis Meyrick (Lepidoptera, Xyloryctidae) on tea (Camellia sinensis) in Hong Kong
Authors: Bradley J. D.
Published: July 2009

A species of Xyloryctid moth bred from larvae feeding on the leaves of tea (Camellia sinensis) in Hong Kong is described as new and is named Neospastis sinensis sp.n. The species is differentiated from the three other known representatives of the genus, and also from Synchalara rhombota (Meyr.), which is a pest of tea in India, and S. rhizograpta Meyr., which was originally described from China. Illustrations of both sexes of the adult and genitalia and of N. sinensis are given.
Reactions of larvae of Plodia interpunctella (Hb.) (Lep., Pyralidae) to insecticidal droplets
Authors: Antunes de Almeida A.
Published: July 2009

In tests of the reactions of freshly hatched larvae of Plodia interpunctella (Hb.) to droplets of liquids containing an insecticnde, 16 droplets of the test material were disposed in a ting 23 mm. in diameter on a glass surface. The mean diameter of dtoplets of the different oils used as solvents varied from about 330 to 615 μ. Minute glass beads about 680 μ in diameter were used as controls. The larvae were tested individually by placing them at the ecntre of the ring and noting whether ot not they succeeded in escaping from it without making contact with a droplet, and their time to do so, termed the avoiding-time.

Six petroleum hydrocarbon oils, and pyerthrin at different concentrations in one of them (Shell Risella Oil 17) and pyrethrin synergists, piperonyl butoxide and Bucarpolate (2-(2-n-butoxyethoxy)ethyl 3,4-methylenedioxybenzoate), were tested. Droplets containing 20 per cent. pyrethrins proved the most repellent, over 98 per cent. of the larvae avoiding contact with them, whereas only 47.5 per cent. avoided the glass beads. The degree of avoidance elicited by the oils was inversely related to the values of their physical characteristics, such as initial boiling point and mean molecular weight. Increasing concentrations of pyrethrins increased both the degree of avoidance and the avoidingtime, and the addition of piperonyl butoxide or Bucarpolate enhanced both these reactions.
Chemical control of potato tuber moth, Phthorimaea operculella (Zell.), in Rhodesia
Authors: Richardson Margaret E. , Rose D. J. W.
Published: July 2009

An account is given of the history of chemical control Phthorimaea operculella (Zell.) in potato fields in Rhodesia since the introduction of DDt prior to 1952. The failure of DDT and endrin, in routine spraying, to control field infestations is reproted, and some evidence that this is due to insecticide resistance is given. The results of critical field trials made in 1961, 1964 and 1965 to evaluate a range of insecticides for control of P. operculella and for their effects on populations of Macrosiphum euphorbiae (Thos.) are presented, together with the results of some laboratory tests. Good control of P. operculella in the field was obtained with sprays of azinphos-methyl at the rate of 0.5 lb active ingredient in 20 gal. water per acre, and two new compounds, methidathion and chlorfenvinphos, showed promise for the future.
Agromyzid leafminers and their parasites in Iraq
Authors: Al-Azawi A. F.
Published: July 2009

Following heavy infestations of garden pea (Pisum sativum) by leadmining insects at an experimental farm near Baghdad in 1963, collections of infested leaves from crop plants and associated weeds were made in 1963–1965 in central and souther Iraq and teh insects emerging from them identified. These included the following six pieces of Agromyzid flies: Phytomyza atricornis Mg., Liriomyza congesta (Beck.), L. Brassicae (Ril), L. strigata (Mg.,) Liriomyza sp. and Agromyza nana Mg. Of these, P. atricornis was the most abundant and widely distributed, followed by L. congesta.

P. atricornis was found on a wide range of hosts, of which P. sativum and Taraxacum monochlamydeum wwre those most attacked. Six species of Hymenopterous parasites were recorded from P. atricornis and these are listed.
The relative potency of insecticides to tsetse flies assessed by two methods
Authors: Busvine J. R. , Abdurrahim U. , Mohammed N. N.
Published: July 2009

The insecticidal Potencies of DDT, dieldrin, isobenzan, malathion, diazinon and arprocarb were assessed both by topical application of oil solutions to test insects any by exposing the latter to residues on glass, using young male and non-pregnant female adults of Glossina morsitans submorsitans Newst., G. austebi Newst., and Chrysomya putoria (Wied.).

By topical application, dieldrin and isobenzan were 10–23 times as potent as DDT, but their residues were on ly 2.2–6.3 times as effective; arprocarb was likewise more effective by topical application than as a residue, being, respectively, 9 and 3.5 times as effective as DDT. In contrast, diazinon, and, especially, malathion tended to be more efficient, relative to DDT, as residues than might be expected from application tests.

It is presumed that the difference between the ralative potency of an insecticide as a reesidue and as applied topically reflects the physical factors affecting contamination and penetration of the insect, but these matters have nor been stuided with tsetse flies.
A method of maintaining Glossina austeni Newst. singly, and a study of the feeding habits of the female in relation to larviposition and pupal weight
Authors: Nash T. A. M. , Jordan A. M. , Boyle J. A.
Published: July 2009

To permit detailed study of individual tsetse, either as insects or as the vectors of trypanosomiasis, a method has been devised which resulted in excellent survival and reproduction when tested on females or Glossina austeni Newst.

Each mated female was maintained in asmall cage comprising a stainless steel frame covered with non-absorbent black Terylene netting through which the larvae and faeces fell into a tray. Each cage was applied daily to the ear of a rabbit, and records were kept of the number of feeds, time taken to feed, numbers of larvae produced, lengths of interlarvel periods and weights of pupae.

The following conclusions are tentative as they are based on detailed studies of only eight females. Five of these produced larvae regularly at 8½- to 9-day intervals. Ninety-six interlarval periods were investigated. Although the mean interval between meals was two days, the flies tended to fast before larviposition and to engorge repeatedly afterwards.

Among nearly regular breeders, failure to larviposit did not seem to interrupt the normal feeding rhythum: the reproductive rhythum later re-integrated with the feeding ehythum. A tendency to deviate from the normal feeding pattern either by too frequent feeding after larviposition or by prologation of the fasting period before larviposition, may possible be related to pemature death, but flies which tend to feed on the day before larviposition centainly risk death from pupation in utero—a condition found in 5 per cent. of dead rabbit-fed flies; the complex of pressures which lead to this condition is described.

Limited data suggest that females which live to a great age enter a post-productive period when about 6½ month old; the feeding pattern breaks down completely, the fly fasting for periods of up to 11 days, or even longer in the immediate pre-death period. The maximum output of reasonably sized pupae is probably about 20 for G. austeni.

Pupal weight increased until the parent flies were about 90 days old, but there was much individual variation; thereafter the weight remained high, but among very old dlies it fell towards the end of reproductive life. Certain individuals tended to produce heavy pupae, a characteristic probable associated with the size of the fly and the total weight of blood taken up in each interlarval period—not with the frequency of feeding; a very infrequent feeder may, however, produce underweight pupae at irregular intervals.
Descriptions of larval and pupal stages of four Lepidopterous rice borers in Malaysian Borneo (Sarawak)
Authors: Rothschild G. H. L.
Published: July 2009

The larvae and pupae of Tryporyza innotata (Wlk.), T. incertulas (Wlk.), Chilo suppressalis (Wlk.), C. polychrysa (Meyr.) (Pyralidae) are described and notes are given on Sesamia ingerens (Wlk.) (Noctuidae) with particular reference to setal characters of the larvae. No obvious difference in chaetotaxy was found between T. incertulas and T. innotata, but the two species of Chilo could be distinguished on this basis. The pupae of the species of Tryporyza could be separated by differences in the shape of the labrum and those of the species of Chilo by differences in that of the thoracic tubercles.
A new genus and species of Delphacidae (Homoptera: Fulgoroidea) infesting molasses grass in Kenya
Authors: Fennah R. G.
Published: July 2009

A new genus and a new Malsxoodes farinosus Fennah, are erected to accommodate examples of a population of Tropidocephaline Delphacidae (Homoptera: Fulgoroidea) found infesting Molasses Grass (Melinis minyutiflora) at Kitale, Kenya.