bluuebunny/crossref_metadata_2025 huggingface dataset:
Uroplata lantanaeBuzzi & Winder (Coleoptera: Chrysomelidae: Hispinae), a Potential biological control agent ofLantana camarain Australia
Authors: Winder J. A. , Harley K. L. S. , Kassulke R. C.
Published: July 2009

Field studies were carried out between 1974 and 1978 on the hispineUroplata lantanaeBuzzi & Winder which feeds onLantana tiliaefoliaplants under shade in temperate climate areas of Paraná State, southern Brazil. The life-cycle from egg to adult took 48–54 days between October and January with only one generation a year. Adults fed by rasping leaves and larvae mined leaves, occasionally destroying up to 24% on individual plants. Adults colonised tall plants preferentially and chose to oviposit on the higher branches, which suffered significantly less leaf abscission. Greater numbers of all stages of the hispine were found on lantana plants around which a plant-free zone was created compared with those growing amongst other understorey plants. Larvae were parasitised by a complex of braconid, eulophid, chalcid and torymid parasitoids, with greater parasitisation occurring at lower branch heights. Multiple-choice host-specificity tests and field observations showed thatU. lantanaefed only onL. tiliaefoliaandL. camara. The effectiveness ofU. lantanaeas a biological control agent of lantana in Australia is discussed.
Infection of Strategus aloeus (L.) (Coleoptera: Scarabaeidae) and other Dynastinae with Baculovirus oryctes
Authors: Lomer C. J.
Published: July 2009

Adults of Strategus aloeus (L.) were shown to be capable of supporting Baculovirus oryctes replication. This was confirmed by serology and by restriction endonuclease analysis. Although bioassays were not performed, the quantity of virus produced was similar to that produced in Oryctes rhinoceros (L.) and should encourage further trials on the potential of this virus to control S. aloeus. Scapanes australis (Boisduval) and Papuana biroi Endrödi did not support adequate virus replication. Previous findings on the susceptibility of O. monoceros (Olivier) were confirmed.
The use of biochemical tests to identify multiple insecticide resistance mechanisms in field-selected populations of Anopheles subpictus Grassi (Diptera: Culicidae)
Authors: Hemingway J. , Jayawardena K. G. I. , Weerasinghe I. , Herath P. R. J.
Published: July 2009

Anopheles subpictus Grassi in Sri Lanka is under selection pressure from both agricultural and public health insecticides. Agricultural selection pressure has produced larval specific carbamate resistance which appears to be correlated with high esterase activity. High esterase activity was found in both larvae and adults, but one of the larval elevated bands was not present in the adult, and two other adult bands were not found in the larvae. Broad spectrum organophosphate resistance was found in both the larvae and the adults and was associated with an increase in mixed-function oxidase activity. There was no evidence of an altered AChE mechanism in this population.
Population studies, physiological state and mortality factors of overwintering adult populations of females ofCulex pipiensL. (Diptera: Culicidae)
Authors: Onyeka J. O. A. , Boreham P. F. L.
Published: July 2009

The biology of overwintering populations of adults ofCulex pipiensL. was studied between October 1977 and April 1980 in southern England. Data obtained from population studies showed that there was a rapid build-up at the beginning of hibernation in August, reaching a peak in late October-early November each year and gradually decreasing from December. Extensive movement both in and out and within the hibernation site occurred, with many individuals changing their locations or hibernacula during the course of hibernation. Studies on induced feeding showed that in the early months of hibernation (August-October) exposure to constant light for a minimum period of 12 days was required before the females would take a blood-meal. This period decreased during the course of hibernation. Observations on the physiological condition of hibernating females revealed that up to 90% of the population were inseminated. A few parous females entered hibernation shelters at the onset of winter but did not survive the winter. Furthermore, females used up about 80% of their fat food reserves during hibernation, while there was little or no change in the quantity of glycogen present. From an assessment of the impact of mortality factors on a population of known size, it was observed that exodus from the hibernation shelters accounted for about 30% reduction in the population size while depletion of food reserves and predation by spiders accounted for approximately 15 and 20% mortality, respectively.
Aspects of the population dynamics of adults of Haematobia thirouxi potans (Bezzi) (Diptera: Muscidae) in southern Africa
Authors: Fay H. A. C. , Doube B. M.
Published: July 2009

Changes in adult populations of Haematobia thirouxi potans (Bezzi) were studied in Hluhluwe Game Reserve, Natal, South Africa, between October 1981 and May 1983. While there were no unequivocal seasonal changes in fly abundance, population increases were recorded late spring–early summer and mid–late autumn. Of the two measures of fly abundance, namely the number of flies that emerged from dung pads almost free of other fauna and counts of flies from culled buffalo (Syncerus caffer), the former was correlated with the proportion of nulliparous females in the population (r = 0·82). While the average female completed a minimum of 2·7 ovarian cycles, up to 78% of females during winter were in the 4th or subsequent cycle. The size of flies collected from buffalo and from dung pads showed an overall reduction during the study period and was an important factor in both survival and fecundity. Differences in the preference of flies for buffalo over an Afrikander-Shorthorn cross heifer, were manifested in the sex ratio and proportions of nulliparous females and fed flies.
Mechanized extraction of arthropods from cattle dung
Authors: Sutherst R. W. , Macqueen A. , Kelley B. M. , Stegeman D. A. , Asher K. G. , Tozer R. S.
Published: July 2009

Ecological, population and community studies of arthropod fauna inhabiting dung require large-scale quantitative data to produce statistically adequate results. A mechanized extraction technique is described which recovers fauna accurately and rapidly from large numbers of cattle dung pads. The equipment comprises a motor-driven paddle which agitates the dung sample in a bucket with fine mesh panels inlaid into its walls and through which is passed a continuous flow of water. An electric motor drives five such units simultaneously. Most dipteran puparia and adult arthropods float on water and are recovered following the washing. Puparia are recovered manually, while mites and adult beetles are extracted from the floating debris with heat in modified Berlese-Tullgren funnels. The wash bucket and its drained contents are then immersed in a flotation vat through which a sodium carbonate solution is recirculated. Insect eggs and larvae are floated off into sieves and rinsed before preservation. The resulting samples are fixed and preserved in 70% ethanol for later identification and counting. The procedure recovered 70–90% of most types and stages of dung fauna. Up to 25 complete dung pads can be processed per day with a team of three people.
Phenacoccus gossypiiTownsend & Cockerell,P. madeirensisGreen and some related mealybug species (Hemiptera: Pseudococcidae)
Authors: Williams D. J.
Published: July 2009

The identity ofPhenacoccus gossypiiTownsend & Cockerell is established as a local species in Mexico and southern USA. AlthoughP. madeirensisGreen was described from Madeira and is recorded from much of the African mainland, it was probably introduced from tropical America. It is now known to be common on many crop and ornamental plants in North and South America where it has often been mistaken forP. gossypii. Both species are redescribed and illustrated, and their range of variation is discussed.P. grenadensisGreen & Laing andP. harbisoniPeterson are synonymized withP. madeirensis. A related species,P. baccharidissp. n., is described from Brazil, andP. sphaeralceaesp. n. is described from Arizona.P. hurdiMcKenzie is redescribed and is now recorded from an extensive area in southern USA and Mexico. All five species have numerous dorsal multilocular pores and are included in a key to 15 related species in North and South America.
Avermectins in insect control and biology: a review
Authors: Strong L. , Brown T. A.
Published: July 2009

In a variety of laboratory and field experiments, avermectins have been tested against some 84 species of insects in ten orders, most of which are pests of livestock or horticultural crops or are of general nuisance value. This work is reviewed, comparing doses used, methods of application, and responses of the insects. Avermectins (abamectin and ivermectin) are toxic to almost all insects examined, although tolerance varies and death can be uncommonly slow, taking 24 h to 30 days. There is a marked absence of information on physiological processes that are affected by the pesticides, although at the cellular level they are thought to disrupt receptors for y-aminobutyric acid and glutamic acid in the central nervous system and muscular system. At high doses, treated insects are progressively immobilized, and although initially many can move when stimulated, this ability becomes lost. Some show a disturbed water balance and become distended with fluid, while others show disruption of moulting and metamorphosis. Feeding inhibition is commonly observed at sub-lethal doses. Avermectins affect many aspects of reproduction including mating behaviour, egg development, oviposition and egg hatching. The possibility is raised that these diverse disturbances are not all due to disruption of neuromuscular or central nervous system synapses, and the need for work in this area is stressed. Field studies have shown ivermectin to be most valuable in eradicating insect pests of livestock, but the use of abamectin against horticultural pests has produced less impressive results. The limited work on non-target species is discussed, and attention is drawn to some possible environmental consequences of excreted ivermectin on dung-breeding insects.
A sensitive and efficient isoenzyme technique for small arthropods and other invertebrates
Authors: Easteal Simon , Boussy Ian A.
Published: July 2009

An electrophoretic method for the study of enzyme variation, which uses cellulose acetate sheets with an agar overlay for staining, the use of a very good general purpose buffer (citric-aminopropyldiethanol amine) and the use of sodium azide as a bacteriocide to allow long term storage of chemicals as solutions are described. Tests are reported of the technique onTetranychus urticaeKoch,Aedes aegypti(L.) and several species ofDrosophila. The results demonstrate that the technique offers sensitivity equal to or greater than starch or polyacrylamide gel electrophoresis and that it is applicable to very small organisms, allowing either the testing of single individuals for large numbers of enzymes or the testing of fewer enzymes under different electrophoretic conditions (i.e. to detect cryptic variation under a single condition). The technique is efficient of time and materials, and safer than conventional methods.
Food quality and foraging response by the subterranean termite Coptotermes formosanus shiraki (isoptera: rhinotermitidae)
Authors: Waller Deborah A. , Fage Jeffery P. La
Published: July 2009

In previous laboratory studies, it was demonstrated that baldcypress (Taxodium distichum) diets eliminated a critical gut protozoan, Pseudotrichonympha grassii, from Coptotermes formosanus Shiraki. The present authors surveyed field colonies of C. formosanus confined within baldcypress trees growing in a river in Louisiana and found P. grassii was present. Termites inhabiting baldcypress trees preferred pine (Pinus) and rejected baldcypress in choice tests in the field. Significantly more termites were recruited to baits when twice as much pine was offered, indicating that C. formosanus adjusted its foraging response to resource amount. In laboratory tests, sound baldcypress sapwood and heartwood depressed survival and gut protozoan counts in C. formosanus, but baldcypress infected with the basidiomycete fungus Rigidoporus sp. and an unidentified imperfect species was favourable for the termites and their symbionts. These results suggest an important role for microbial modification in termite host selection.
Acclimation to, and recovery from, low temperatures in scottish clones ofmyzus persicae(sulzer) andaulacorthum solani(kaltenbach) (hemiptera: aphididae) susceptible and resistant to organophosphates
Authors: Pozarowska Barbara J.
Published: July 2009

Acclimation had a beneficial effect on Scottish clones of Aulacorthum solani (Kaltenbach) as seen in enhanced reproduction and development at 5°C, compared with non-acclimated clones at this temperature. In contrast, not all Myzus persicae (Sulzer) clones tested benefited. When reared at 5°C for a second generation, both species had slower nymphal development and M. persicae also had less efficient adult reproduction (a longer pre-reproductive period and reduced fecundity) compared with the first generation. Both species demonstrated a high capacity for recovery from low temperatures, A. solani being the better of the two. In general however, the ability of clones to survive, reproduce and develop at low temperatures or upon transfer to high temperatures, was variable and was not related to annual cycle, origin or organophosphorus resistance. These differing responses support previous results and are suggested as being an efficient means of ensuring variability in aphid populations surviving after winter.
Aspects of migration and colonization of the coconut palm by the coconut mite, Eriophyes guerreronis (Keifer) (Acari: Eriophyidae)
Authors: Moore D. , Alexander L.
Published: July 2009

Migration and colonization of the coconut palm by Eriophyes guerreronis (Keifer) was studied in St Lucia in the West Indies. Mites were not found in unfertilized flowers but were present within a few weeks of fertilization. Nuts remained vulnerable to colonization for a number of months, and mites were present on nuts for up to 13 months. Protection of nuts for the first few months after fertilization is of most importance. On the tree, much migration could be due to mites walking in large numbers across nut surfaces, and they could move from one inflorescence to another if the two were in contact. Increased nut damage appeared to encourage mite migration.
Morphological discrimination of a tobacco-feeding form from Myzus persicae (Sulzer) (Hemiptera: Aphididae), and a key to New World Myzus (Nectarosiphon) species
Authors: Blackman R. L.
Published: July 2009

Multivariate techniques, principally the method of canonical variates, were used to investigate morphological variation within and between populations of the group of Myzus persicae (Sulzer) from North and South America, Europe, Africa and Asia. The scores on the first canonical variate of samples from tobacco in North America, the Mediterranean region, the Middle East, Africa and Sri Lanka all grouped consistently when compared with samples from other host-plants, even after aphids from tobacco had been reared for up to seven years on a non-tobacco host. Thus there is a widely-distributed tobacco-adapted form, closely related to M. persicae but with its own characteristic morphology. Morphological discriminants are given for the recognition of apterous and alate viviparae of this tobacco form, which is given the name M. nicotianae sp. n. Both M. persicae and M. nicotianae have 2n = 12, and both are frequently heterozygous for apparently the same autosomal translocation, which they must have acquired independently. M. nicotianae is presumably isolated from M. persicae by being permanently parthenogenetic. In Japan and Central Asia, however, aphids of the M. persicae group on tobacco can produce sexual morphs; the taxonomic status of these latter populations is still unclear. Multivariate comparison of European and North American populations of dark green aphids of the M. persicae group with 13 or 14 chromosomes in somatic cell nuclei instead of the normal 12, led to the conclusion that these all belong to one morphologically variable taxon, M. antirrhinii (Macchiati). Keys are provided to the apterous and alate virginoparae of the species of the M. persicae group in America.
The Solitary Phase of Schistocerca Gregaria, Forsk., in North-Eastern Kordofan (Anglo-Egyptian Sudan)
Authors: Maxwell-Darling R. C.
Published: July 2009

This is an account of work carried out in Kordofan on behalf of the Imperial Institute of Entomology. The period August-September 1931 was occupied with preliminary surveys and observations on hopper bands. From July to September 1932 and from March to July 1933 the ecology of the solitary phase of Schistocerca gregaria was studied at Um Darag ; and in January 1933 a locust survey of the more northern parts was carried out.
Fertility and Climatic Adaptations in Siberian Grasshoppers
Authors: Rubtzov I. A.
Published: July 2009

1. The number of egg-tubes and the number of eggs in each tube varies in accordance with the food and the climatic and microclimatic conditions of each habitat. The majority of Siberian grasshoppers have adaptations in the ovaries which enable them to take full advantage of the available heat.

2. In the species possessing 10 or more egg-tubes, their number varies in different parts of the distribution area. It decreases towards the centre of the area with increasing warmth and dryness, and increases towards the colder and more humid margins of that area (e.g., in the Far East and in Western Europe).

3. The potential fertility is more or less stable in different species of grasshoppers, and in the species studied it fluctuates between 84 and 388 eggs per female.

4. There is no correlation between the potential fertility and the abundance of the species in nature, for the greatest fertility is met with in those species which occur but rarely. The injurious (i.e., very numerous) grasshoppers have a medium, or somewhat less than a medium, potential fertility.

5. The actual fertility is greatly dependent on the environment and has a wide range of fluctuation.

6. Lack of food in reservations was observed to lower the fertility of grasshoppers by 30–40 per cent. The parasites (Blaesoxiphaspp.,Mermisspp.) greatly reduce the degree of fertility of the Siberian grasshoppers. However, the percentage of infestation by these parasites is low, but in the reservations it is somewhat higher than outside. Thus, the actual fertility in reservations is rather lower than outside.

7. The outbreaks of the Siberian grasshoppers are determined by the climatic and microclimatic conditions. The fluctuations in fertility never have any real importance in causing the outbreaks. Lack of food, parasites, predators and diseases are of minor importance; among the latter the main factors are the diseases of the egg-pods, which again depend on the microclimate.
Further Studies upon Chemical Factors Affecting the Breeding of Anopheles in Trinidad
Authors: Buxton P. A.
Published: July 2009

During the last decade, entomologists have made progress in understanding the environment in which certain insects live; in particular, we begin to understand the effect of certain physical and chemical factors, which make up a part of the environment. With this gain in knowledge, it is sometimes possible to forecast outbreaks of insects and of diseases conveyed by them, and one can sometimes say that a particular alteration of the environment will result in loss or gain. But so far as mosquitos are concerned, one must admit that though much work has been devoted to the analytical study of the water in which the early stages are passed, the results are disappointing. A consideration of the published work suggests several reasons for this. Investigation into the ecology of the mosquito has had a vogue, and much of it has been done by workers who were isolated and whose knowledge of chemical technique and freshwater biology was limited. Apart from that, the inherent difficulties are great, for the worker must hunt for the limiting chemical and physical factors among a host of others which are doubtless unimportant, and there are few clues to indicate which of the chemical constituents of the water affects the mosquito. The data are therefore voluminous and it is difficult to reduce them to order and present them so that they can be readily understood.
Notes on Dutch East Indian Mosquitos
Authors: Brug S. L.
Published: July 2009

Most of the mosquitos described here were collected by Dr. H. de Rook and the author during a tour of investigation of filariasis in the eastern part of the Malay Archipelago. The tour was undertaken with a grant from the “Koningin Wilhelmina Jubileum-Stichting” in Batavia.
Varying durations of arrested oocyte development in relation to migration in the African armyworm moth, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae)
Authors: Page W. W.
Published: July 2009

The rate of oocyte development in Spodoptera exempta (Walker) was investigated in the laboratory and in the field in Kenya. Stages and rates of development were examined in relation to moth size and timing of mating and oviposition. The stage of oocyte development was established by measuring the widths of the second or third oocyte at the distal end of one ovariole. Data from moths of known age showed that oocytes were partially developed at eclosion and that a linear progression in development occurred up to 30 h after emergence, by which time the oocytes had reached approximately half their mature size. Oocyte development continued unbroken in some moths up to the time of oviposition on the second night after emergence, whilst the remainder arrested oocyte development for a varying number of days. Mating occurred after midnight, but only once the oocytes had reached a certain size, irrespective of whether development was continuous or arrested. In the latter case, this stage was reached immediately after development resumed. Oviposition usually occurred the night after mating, mainly around midnight and with a second peak towards dawn. The dawn peak derived from mature moths which mated and oviposited on the same night. It is suggested that moths arrest oocyte development to minimize wing loading during migration and that, since moths stay in arrested development for varying lengths of time (thought to be genetically regulated), dispersal is greatly enhanced.
Preliminary spray trials of a nuclear polyhedrosis virus as a control agent for the brown-tail moth, Euproctis chrysorrhoea (L.) (Lepidoptera: Lymantriidae)
Authors: Kelly P. M. , Sterling P. H. , Speight M. R. , Entwistle P. F.
Published: July 2009

A spray trial of a nuclear polyhedrosis virus (NPV) as an insecticide for Euproctis chrysorrhoea (L.) is described. The trial was carried out indoors in the spring on third-instar larvae emerging from overwintering nests onto small potted hawthorn trees (Crataegus sp.); the equipment used was the Turbair Fox Ultra Low Volume Sprayer. Dosages applied ranged from equivalents of 1 × 1011 to 1 × 1013 polyhedral inclusion bodies (PIB) per hectare. Infection was first detected in samples of live larvae after ten days and indicated rates of infection consistently lower than the final mortality attained. Larvae began to die of NPV infections 11 days after spraying, and mortality due to the virus ceased after ca 20 days; most larvae died in the fourth instar. Over the range of virus doses from 1 × 1011 to 5 ×10 12 PIB/ha mortality levels rose with dose, to a maximum of over 90%. Increasing the dosage to 1 × 1013 PIB/ha elicited no further increase in mortality. This preliminary trial suggests that the virus has considerable potential as a control agent, and field trials are, therefore, in progress.
Monitoring of endosulfan and lindane resistance in the coffee berry borer Hypothenemus hampei (Coleoptera: Scolytidae) in New Caledonia
Authors: Brun L.O. , Marcillaud C. , Gaudichon V. , Suckling D.M.
Published: July 2009

Endosulfan resistance in the coffee berry borer Hypothenemus hampei (Ferrari) was discovered in New Caledonia after six years of lindane and 12 years of endosulfan biannual applications. The direct spray technique was used to study cross resistance with lindane and to monitor resistance to both pesticides in 15 regions of New Caledonia. An easier monitoring technique was developed for early detection by field laboratories. Results from this simple method, using twice the LC99 of endosulfan to susceptibles (400 ppm) showed a comparable distribution of resistance to the direct spray method in five regions where resistance was detected. The percentage of surveyed fields containing resistant insects in these areas was: Poindimié, 100%, Ponérihouen, 97%; Touho, 63%; Houailou, 10%; Hienghène, 6%. Resistant insects were significantly more frequent in the new sunny fields than in older shady plantations (P<0.05), and fields with endosulfan used in the preceding year (P<0.001). The possible reasons for the observed distribution of resistance are discussed.
Field evaluation of methyl 4-methylpyrrole-2-carboxylate, an ant trail pheromone, as a component of baits for leaf-cutting ant (Hymenoptera Formicidae) control
Authors: Robinson S. W. , Jutsum A. R. , Cherrett J. M. , Quinlan R. J.
Published: July 2009

In the laboratory, the trail pheromone methyl 4-methylpyrrole-2-carboxylate (M4MP2C) when added to bait particles acts as an attractant to leaf-cutting ants, increasing the pick-up of pheromone-impregnated bait compared with plain bait. However, field trials in Trinidad, Brazil and Paraguay were disappointing. Bait with and without pheromone was scattered in the foraging area, and the proportion of each taken to the nest by Atta sexdens rubropilosa Forel, A. cephalotes (L.) and Acromyrmex octospinosus (Reich) was assessed. In only one of the experiments (A. octospinosus foraging bait with 50 p.p.m. of M4MP2C) was increased pick-up detected. Four reasons for this are suggested: (1) small pheromone effects are difficult to measure as scattering bait produced a patchy distribution and heterogeneous replicates, whilst choice trials on plain and pheromone-impregnated bait placed close together were difficult to interpret, as the pheromone probably excited the ants, increasing pick-up of plain bait; (2) A. octospinosus workers, the subject of detailed studies, were less sensitive to M4MP2C in the field than in the laboratory; (3) as the pheromone only attracts, it does not produce a comparable increase in the number of pieces picked up, contact/pick-up ratios of sucroseimpregnated discs increasing from 2·26 at 5 pg pheromone to 16·39 at 50 ng; and (4) soyabean oil, citrus-pulp extract and orange juice were found to be attractive, and when pheromone was added, its effects were not additive. Early studies used sucrose-impregnated paper discs, and as these have no attractants of their own, the addition of M4MP2C had a more marked effect. It is concluded that M4MP2C is not a cost-effective addition to current leaf-cutting ant baits which possess food odours, a much cheaper source of attractiveness.
The role of bacterial odours in oviposition byLucilia cuprina(Wiedemann) (Diptera: Calliphoridae), the Australian sheep blowfly
Authors: Emmens R. L. , Murray M. D.
Published: July 2009

Extracts from cultures ofPseudomonas aeruginosa, Bacillus subtilis, Proteus mirabilisandEnterobacter cloacaein samples of fleeces from sheep were incorporated into nutrient agar and exposed to females ofLucilia cuprina(Wied.) in cages. The blowflies often laid eggs in response to the odours emanating from the cultures of all bacteria.Pseudomonas aeruginosaandE. cloacaedid not appear to utilise fleece components in the production of oviposition stimulants, whereasB. subtilisdid, utilising compounds such as palmitic acid, andProteus mirabilisdegraded wool fibres to produce sulphurous compounds. The results are discussed in relation to the role ofL. cuprinain cutaneous myiasis of sheep.
Sterilising effects of benzyl-l,3-benzodioxoles on the tsetse fly Glossina morsitans morsitans Westwood (Diptera: Glossinidae)
Authors: Langley P. A , Trewern M. A , Jurd L.
Published: July 2009

Three benzyl-l,3-benzodioxoles and three benzylphenols were tested for their ability to sterilise Glossina morsitans morsitans Westw. following topical application in acetone. Two of the former compounds, 5-ethoxy-6- (4-methoxyphenylmethyl)-l,3-benzodioxole and 5-ethoxy-6-[l-(4-meth-oxyphenyl)ethyl]-l,3-benzodioxole, caused total sterility in females at a dose of 10 μg per fly, and remained effective even after one year's storage at 4°C. Dose-fecundity data indicate a reduction to 50% fecundity (ED50) was achieved with 2·5 μg of the former or 0·5 μg of the latter per fly. An ED90 of 8·5 μg and 2·5 μg, respectively, is indicated. The latter compound reduced the survival of treated females and males and surviving males were incapable of inseminating even though copulation appeared normal. The effects on female survival and fecundity, of feeding the compounds at 0·25 and 1·0% in blood, were variable, owing to their low solubility and variations in the size of blood-meals. The highest doses of the former compound led to ovarian atrophy in females, which can be described as an effect on fecundity. Lower doses induced sterility through egg death and atrophy after ovulation. The latter compound acted more rapidly than the former, preventing ovulation of the first mature oocyte in a higher proportion of flies. The activity of these compounds, which were derived by modification of plant materials, and are non-mutagenic, renders them likely candidates for evaluation as contact insecticides for Glossina in the field.
The effect of bed nets on feeding by Anopheles gambiae Giles (Diptera: Culicidae)
Authors: Port G. R. , Boreham P. F. L.
Published: July 2009

In the Gambia, bed nets are often used for protection from mosquitoes although some of the nets are often in poor condition. In a village where the most abundant man-biting mosquito was Anopheles gambiae Giles s.s., nets in different condition were compared by assessing the success of mosquitoes in feeding. All the nets tested reduced mosquito feeding, and this reduction correlated with the number and size of holes in the nets. The experiments were conducted in purpose-built huts with verandah traps to sample the mosquito population leaving the hut. Although the majority of males and fed females of A. gambiae remained in the huts each morning, unfed females usually left the huts the same night, probably in search of alternative food sources.
The distribution and movement of engorged females of Anopheles gambiae Giles (Diptera: Culicidae) in a Gambian village
Authors: Boreham P. F. L. , Port G. R.
Published: July 2009

The distribution of fed mosquitoes in a village in the Gambia where bed nets are widely used was studied. A total of 3470 blood-meals from Anopheles gambiae Giles s.s. and other mosquitoes was analysed to determine the human blood index (HBI). A. gambiae s.s. collected within nets gave an index of 0·99, whereas those within houses but outside nets gave an index of 0·70. The importance of distinguishing biotopes when presenting HBI values is stressed. By using a unique host, mosquitoes were ‘ marked ’ (with a blood-meal) and their dispersion was studied. Evidence was obtained for movement from house to house and from outside into houses before resting.
The biology and host specificity ofLiothrips mikaniae(Priesner) (Thysanoptera: Phlaeothripidae), a potential biological control agent ofMikania micrantha(Compositae)
Authors: Cock M. J. W.
Published: July 2009

Liothrips mikaniae(Priesn.) comb. n. is one of the most promising biological control agents forMikania micrantha, a sprawling composite vine native to the Neotropics which is a serious weed of plantations in South-East Asia. A description and illustrations of the adult and larvae of this thrips is followed by details of the life-history, culture technique, host specificity (including laboratory studies demonstrating oligophagy) and natural enemies. It is recommended for introduction to South-East Asia.
Selection for increased resistance to a granulosis virus in the potato moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)
Authors: Briese D. T. , Mende H. A.
Published: July 2009

Serial exposure of a susceptible laboratory strain of Phthorimaea operculella (Zell.) recently obtained from the field to granulosis virus over six generations produced a 140-fold increase in LD50. The evidence suggests that this was due to a change in frequency of a resistance gene within the population. An attempt to select for even greater resistance in an already highly resistant laboratory strain resulted in only a small increase, due mainly to reduced variability in response of the population. The implications of resistance to viral insecticides developing under field conditions are discussed.
The effects of Empoasca dolichi Paoli (Hemiptera: Cicadellidae) on the performance and yield of two cowpea cultivars
Authors: Parh I. A.
Published: July 2009

The effects of feeding by groups of 0, 15, 30, 45, 60, 75 or 90 adults of Empoasca dolichi Paoli per plant on the growth and yield of caged Prima and Ife Brown cowpea plants infested 14, 21 or 28 days after planting were studied in Ibadan, Nigeria. Caging had no significant adverse effects on yield. E. dolichi caused severe hopper-burn in plants infested 14 days after planting. The mean pre-flower-opening stage lasted 42–1, 38–0 and 39–0 days in Prima and 446, 407 and 423 days in Ife Brown plants infested 14, 21 and 28 days after planting, respectively, the first figure for each cultivar being significantly different from the other two. The mean yields were 23 3, 28 5 and 298 pods per plant for Prima, and 350, 48–1 and 437 for Ife Brown, respectively, the first figure for each cultivar being significantly lower than the other two. The reduction in seed yield in damaged plants infested 14 days after planting ranged from 287 to 413% for Prima and 272 to 56–9% for Ife Brown, the reductions being significantly correlated with scores for feeding damage by E. dolichi.
The assessment of mealybugs (Pseudococcidae) and other Homoptera on mature cocoa trees in Ghana
Authors: Campbell C. A. M.
Published: July 2009

The numbers of mealybugs and other Homoptera on 96 cocoa trees in Ghana were assessed by examining four branches from each tree. The trees were then felled and examined in detail. Ten species of mealybugs, eight other coccoids, an aphid and a psyllid were recorded. Ninety–five of the trees were infested with mealybugs, 66, 90 and 69 trees, respectively, with Planococcoides njalensis (Laing), Planococcus citri (Risso) and Phenacoccus hargreavesi (Laing). Stictococcus sjostedti Ckll., a species of Gascardia near G. zonata (Newst.) and Mesohomotoma tessmanni (Aulm.) were found on 70, 68 and 48 trees, respectively. The remaining 14 species were found on fewer than 48 trees. All species other than Pseudococcus calceolariae (Mask.) and Ferrisia virgata Ckll.) were most prevalent in the canopy. In the field, mealybug densities recorded on shoots underestimated true levels by an average of 95%. Branches were as effective as whole trees for detecting mealybugs, but less effective for other Homoptera. Branches were suitable sample units for estimating population densities of mealybugs, stictococcids and psyllids. All species of mealybug other than F. virgata infested vegetative buds. An average of 21.7% of buds on the youngest shoots were infested. Samples of buds can be used for detecting mealybug infestations.
The biology of the oak bark beetle, Scolytus intricatus (Ratzeburg) (Coleoptera: Scolytidae), in southern England
Authors: Yates M. G.
Published: July 2009

Scolytus intricatus (Ratz.) is a potential vector of oak wilt and is distributed throughout Europe wherever oak (Quercus) occurs. Its biology was studied in England in Monks Wood National Nature Reserve, Cambridgeshire, Alice Holt Forest, Surrey, and the New Forest, Hampshire, in 1977–83. S. intricatus was univoltine. Oviposition occurred from June to September in the bark of cut or weakened oak (Q. robur) over 5 cm in diameter. Eggs were laid in a single batch in maternal galleries cut across the grain of the cambium and phloem. The mean egg batch size was 17–36. Eggs hatched after 10–14 days, and the larvae ate the phloem and underwent five, or occasionally six, instars. The beetle overwintered as third-fifth-instar larvae, which were cold hardy and were located in cells in the phloem or outer xylem. Pupation occurred in spring, in cells in the bark or outer xylem. Emergence occurred between mid-May and mid-July and spanned a period of 3–4 weeks. The sex ratio was 1:1. Males and females differed externally by the presence of a tuft of setae on the frontal-clypeal suture of the head of the male. Newly emerged adults fed on twigs of live oak, but twig feeding was not obligatory for sexual maturation. Mating was observed during attacks on new hosts, which occurred in June-September. The eulophid Entedon ergias Wlk. was an endoparasite of larvae while larvae of the dolichopodids Medetera and Dolichopus and woodpeckers were predators.
The pattern and speed of displacement of females ofSimulium damnosumTheobald s.l. (Diptera: Simuliidae) across the Onchocerciasis Control Programme area of West Africa in 1977 and 1978
Authors: Johnson C. G. , Walsh J. F. , Davies J. B. , Clark S. J. , Perry J. N.
Published: July 2009

Breeding ofSimulium damnosumTheobald s.1., the vector ofOnchocerca volvulus, had been eliminated by 1977 from about 654 000 km2of the Onchocerciasis Control Programme in the Volta River Basin Area (OCP) of West Africa. Nevertheless, migrating adult females continually invaded the controlled area, being blown on the prevailing south-westerly winds from uncontrolled breeding sites beyond the south-western border of the OCP area. Graphs of numbers of females caught per man per day (the daily biting rate) throughout the wet season, March to October, at 16 sites in 1977 within the OCP controlled area were remarkably similar in pattern from site to site over a range of about 500 km downwind. In 1978, only seven sites within the OCP area were similarly monitored, and the graphs were different in pattern from those in 1977, when they each consisted of three or four well-defined waves or cycles of daily biting rate which could be easily identified and traced across country, their times of occurrence lagging increasingly as the distance of the site from the south-western border of the OCP area increased. Four methods were used to demonstrate and estimate the lag: visual comparison of seasonal graphs; comparison of the mean dates of cycles at different sites and the regression of these dates on distance from the south-western border; the dates when particular cumulative percentages of the total season's catch occurred at each site and their regression on distance; and principal coordinate analysis of the data and its relation to distance from the south-western border. Statistically significant lags were demonstrated and averaged one day for every 10–30 km from the border in 1977, which indicated an average speed of migration across country. In 1978, a rate of one day per 7–35 km was indicated. Where some graphs at outlying sites were anomalous, possible alternative sources of immigrant flies are considered. The possible behaviour of flies in causing the lag is discussed.
Larval characteristics of Cactoblaslis spp. (Lepidoptera: Pyralidae) and the selection of species for biological control of prickly pears (Opuntia spp.)
Authors: McFadyen R. E.
Published: July 2009

The black markings on larvae of Cactoblastis spp. can be used to separate different biotypes or species. These markings are figured, together with host and locality records for ten distinct biotypes or species, at least five of which are undescribed. Past introductions of C. cactorum (Berg) and Cactoblastis spp. to Australia and elsewhere are reviewed, and it is suggested that some of the undescribed biotypes might be of value in the biological control of Opuntia spp.
Genetic variation inHeliothisin Australia: species identification and gene flow in the two pest species H. armigera (Hübner) and H.punctigeraWallengren (Lepidoptera: Noctuidae)
Authors: Daly Joanne C. , Gregg Peter
Published: July 2009

Genetic (electrophoretic) variation was examined in the two pest species ofHeliothisfound in Australia,H. armigera(Hübner) andH. punctigeraWallengren. They could be differentiated by seven loci which enabled identification of individual eggs and small larvae not normally distinguishable by their morphology. The traditional criteria for distinguishing the larger larvae of the two species were shown to be unreliable. The genetic distance between the two species was 0·34 ± 0·02. The percentage of loci polymorphic in both species, 32%, and the mean heterozygosities, 11·3% forH. armigeraand 10·8% forH. punctigera, are lower than those reported in the American species,H. virescens(F.) andH. zea(Boddie). Populations throughout Australia were differentiated from each other, but there did not appear to be a marked geographic pattern to the variation. Genetic distances between populations ofH. armigerawere low (<0·01). It was concluded that the effective population size ofHeliothisis large and that significant gene flow probably occurs between widely separated regions.
Genetic investigations of laboratory stocks of the complex of Anopheles balabacensis Baisas (Diptera: Culicidae)
Authors: Hii Jeffrey L. K.
Published: July 2009

Examination of the polytene chromosomes and cross-breeding data confirmed the specific status of Anopheles dirusPeyton & Harrison within the complex of A. balabacensis Baisas. The data also strongly suggested that A. dirus itself is a complex of at least two species, one of which, a hitherto unrecognized species, provisionally designated A. dirus species B, previously known as the Perlis form, occurs in northern Peninsular Malaysia. A distinct population from Thailand was designated A. dirus species A. The mosquitoes studied also include material from natural populations in Sabah, here provisionally designated A. balabacensis s.s., and may represent the first genetic analysis of this species. The Sabah material is distinct from either of the A. dirus forms. Hybrid males from crosses of A. balabacensis × A. dirus species A and of A. dirus species B females × A. dirus species A males were sterile. Chromosome studies also showed that reproductive isolation was accompanied by genetic changes in both the autosomesand X chromosome in the hybrid larvae.
Olesicampe monticola (Hedwig) (Hymenoptera: Ichneumonidae) redescribed together with notes on its biology as a parasite of Cephalcia lariciphila (Wachtl) (Hymenoptera: Pamphiliidae)
Authors: Billany D. J. , Winter T. G. , Gauld I. D.
Published: July 2009

The sawfly Cephalcia lariciphila (Wachtl) is a pest of larch (Larix spp.) that has recently become widespread in Britain. Before taking measures to control the sawfly the status of parasites in the infestations was investigated. The only insect parasite species found was the ichneumonid Olesicampe monticola (Hedwig), which is new to Britain. As this insect is taxonomically so poorly known it is redescribed from specimens collected in South Wales. The preliminary biological observations show O. monticola to be well-adapted to its host and that it can significantly reduce an infestation.
The susceptibility of Glossina pallidipes Austen (Diptera: Glossinidae) to insecticide deposits on targets
Authors: Torr S. J.
Published: July 2009

Studies were made of the susceptibility of wild-caught females of Glossina pallidipes Austen to deposits of DDT, dieldrin and deltamethrin on cotton canvas and Terylene netting. Aqueous suspensions of 3% dieldrin wettable powder, 3% dieldrin emulsifiable concentrate, 5·0% DDT wettable powder and 0·0625% deltamethrin flowable concentrate, were sprayed on the canvas at 0·36% litre/m2 Over 95% of the flies resting for 45 s on fresh deposits of these insecticides died within 72 h. Deposits of dieldrin, DDT and deltamethrin exposed to the sun during 140 days of the dry season produced mortalities of 100, 0 and 10% compared with 100, 75 and 100% for shaded deposits. The concentration of dieldrin and deltamethrin on exposed canvas was about 1% that on shaded canvas, but dieldrin produced photodieldrin upon exposure to the sun. Flies colliding with Terylene netting that had been immersed in 0·75–6·0% suspensions of dieldrin wettable powder and 0·01–0·1% suspensions of deltamethrin flowable concentrate produced mortalities of 100%. Deltamethrin deposits were resistant to weathering by rain, but dieldrin deposits were not. It is suggested that deltamethrin flowable concentrate should be used during the wet season and that dieldrin wettable powder should be used during the dry season. Dieldrin sprayed on an electrocuting target reduced the catch, but deltamethrin did not.
The incidence and distribution of the armyworms Mythimna convecta (walker) and Persectania spp. (Lepidoptera: Noctuidae) and their parasitoids in major agricultural districts of Victoria, south-eastern australia
Authors: McDonald G. , Smith A. M.
Published: July 2009

Field studies of Mythimna convecta (Walker), Persectania ewingii (Westwood) and P. dyscrita Common, and their associated parasitoids, were conducted in cereals and pastures in Victoria, Australia, in 1980–83. The study included a survey of the armyworm fauna in the major agricultural districts, detailed phenological studies within five oat crops, and ultraviolet-light trapping of adults. M. convecta was the most abundant species in cereals and was found more commonly in the warmer months of spring and summer in all districts. Larval development in oat crops during spring was preceded by little moth activity in light traps. P. ewingii was common in the southern districts and in the cooler months from May to September. It was the most prevalent armyworm species in pastures and rarely occurred in barley. P. dyscrita was the least abundant species and occurred mostly in the drier inland areas, particularly in the west. Light-trap catches of P. ewingii and P. dyscrita suggested there were two generations, one in spring and one in the autumn. Regular sampling in oat crops showed that M. convecta developed faster and was usually more abundant than P. ewingii during seed development and ripening, and hence had the potential to inflict more crop damage. Of the 17 species of parasitoids reared from field-collected larvae, the wasp Campoletis sp. was the most abundant. In 1980–82, average parasitism ranged from 13 to 16% but fell to 2% after the drought of 1982.