bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of biodiversity in the dynamics and management of insect pests of tropical irrigated rice—a review
Authors: Way M.J. , Heong K.L.
Published: July 2009

Biodiversity relevant to pest management of tropical irrigated rice pests is discussed in terms of variation within rice plants, rice fields, groups of rice fields and rice associated ecosystems. It is concluded that, in the unique cropping conditions and stable water supply of tropical irrigated rice, the manipulation of a relatively few manageable components of diversity can confer stability such that pests are mostly kept at levels which do not justify the use of insecticides. Durable rice plant resistance, including moderate resistance, together with ability to compensate for damage by certain key pests, are regarded as fundamental to successful biological control by the natural enemy complex. Reliable natural enemy action is also considered to depend on all-year-round continuity of prey or hosts made possible by the relatively short fallow periods between staggered two to three rice crops per year and by proximity of certain non-rice habitats, notably the vegetation-covered bunds (levées) surrounding each field. In contrast, synchronous cropping could upset stability by destroying the continuity needed for natural enemy success. Such conclusions are supported by the experience of farmers who use little or no insecticide. Much evidence on destruction of natural enemies by certain insecticides supports the contention that insecticide use, especially early in the crop season, upsets natural enemy control of insects such as Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) and also creates heavy selection pressure for strains of pests that can overcome previously resistant rice cultivars. Such circumstances create outbreaks of secondary pests and impair biological control of some key primary pests such as stem borers. It is concluded that pest management of much tropical irrigated rice must be based on natural controls rarely supplemented by insecticides. The success of this approach depends in particular on further research on dynamics of natural enemy and pest communities in rice ecosystems, especially where climatic conditions and water supply are marginally stable. Much more needs to be known about the nature and utilization of rice plant compensation for damage, particularly by defoliators and stem borers. The justification for, and supplementary use of, insecticides needs to be radically reassessed. There is no evidence that a natural control-based approach, as recommended in this review, is incompat ible with farmer practicability or with future developments in rice production technology, except perhaps the possible mechanization-driven increase in field size which would decrease bund area. In contrast, the insecticide-based approach is not only harmful to natural controls but is costly and mostly demands impracticable decision making by farmers on need-based use.
Field investigation of an attracticide control technique using the sex pheromone of the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae)
Authors: Downham M.C.A. , McVeigh L.J. , Moawad G.M.
Published: July 2009

A series of trials examining the feasibility of an attracticide technique for control of Spodoptera littoralis (Boisduval) are described. The technique combined the sex pheromone of S. littoralis with pyrethroid insecticide, λ-cyhalothrin, in 500 point-sources/ha at low rates of application of both components. It was envisaged that male moths would be attracted to contact the sources and subsequently suffer lethal or sub-lethal effects which would prevent mating. The pheromone was applied either as a sprayable microencapsulated (MC) formulation or in polyvinyl-chloride lures; emulsifiable concentrate and MC formulations of the insecticide were employed. Treatments were assessed by monitoring pheromone trap catches, mating of tethered females and, in one trial, numbers of eggmasses found in experimental areas. Mating levels and trap-catch in treatment plots were siginificantly reduced, compared to controls, for periods up to 5 and 24 nights after treatment, respectively. However despite a continuous period of mating suppression, achieved by repeated applications, no treatment-related reduction in egg-masses was observed. Two trials compared attracticide with mating-disruption treatments in which the insecticide was omitted. Similar levels of mating and trap-catch suppression were observed in the two treatments. It was concluded that the mating suppression observed in attracticide plots was due principally to disruption of chemical communication between the sexes, not to male mortality arising from contact with the insecticide sources. None of the attracticide treatments represented a viable control technique. Other practical and theoretical considerations arising from the results are discussed.
Predicting the severity of Spodoptera exempta (Lepidoptera: Noctuidae) outbreak seasons in Tanzania
Authors: Harvey A.W. , Mallya G.A.
Published: July 2009

Outbreaks of the African armyworm, Spodoptera exempta (Walker), in East Africa follow a seasonal pattern related to the movement of the inter-tropical convergence zone. The season typically begins in central Tanzania with primary outbreaks that coincide with the arrival of the rains. An analysis of 27 years' light trap records shows a high negative correlation between the total number of moths caught by light traps during the season over the whole country and the number of rain days during November in central Tanzania. Out of the 27 seasons, 22 could have been correctly predicted as ‘light’ or ‘severe’, using the November rainfall at one station, Dodoma, in time to give two months' warning before the peak of the season.
Life cycle of Liposcelis entomophila (Psocoptera: Liposcelididae) and a culturing regime for liposcelids
Authors: Leong Edmund C.W. , Ho S.H.
Published: July 2009

The life cycle of Liposcelis entomophila (Enderlein) (Psocoptera: Liposcelididae) was studied at 30 ± 1°C and 75 ± 3% r.h. The mean developmental period of the females was 22.3 days and that of the males was 18.4 days. This corresponded to the males undergoing three, and the females four, nymphal stages. A 28% developmental mortality was observed. The average number of offspring produced in the first fornight was 9.6 and the natural mortality of the females was noted only from the sixth week, increasing to 54.1% by the 12th week. An extraction and culturing regime to obtain populations of one- to three-week old adult females was developed. This procedure was also found to be ideal for L. bostrychophila Badonnel.
The biology of the ectoparasitoid wasp Eulophus pennicornis (Hymenoptera: Eulophidae) on host larvae of the tomato moth, Lacanobia oleracea (Lepidoptera: Noctuidae)
Authors: Marris G.C. , Edwards J.P.
Published: July 2009

There is a need to identify potential biological control agents for use against noctuid pests in greenhouses. The gregarious ectoparasitoid Eulophus pennicornis (Nees) attacks a limited range of macrolepidopterous larvae, including those of some important horticultural pest species. Laboratory trials designed to investigate the biology of E. pennicornis on larvae of the tomato moth, Lacanobia oleracea Linnaeus, reveal that wasps preferentially parasitize penulitmate (fifth) or final (sixth) instar hosts. More than two-thirds of wasps lay viable eggs, and individual females oviposit on up to four hosts during their lifespan. Wasp fecundity is high, preadult development is rapid, and offspring show a markedly female-biased sex ratio. Parasitized fifth instar L.oleracea hosts do not grow as quickly as unparasitized larvae, and neither do they undergo normal ecdysis to the final larval stadium. Furthermore, the consumption of artificial diet by parasitized fifth instar hosts is greatly reduced in comparison to that of unparasitized larvae (overall feeding-reduction over a 12 day period was 64.7%). Our results suggest that E. pennicornis affects both the developmental and feeding physiology of host larvae, and that inoculative releases of this parasitoid could provide effective biological control for L. oleracea and other greenhouse pests.
The use of random amplified polymorphic DNA (RAPD) analysis for studies of genetic variation in populations of the blowfly Lucilia sericata (Diptera: Calliphoridae) in southern England
Authors: Stevens Jamie , Wall Richard
Published: July 2009

The use of the random amplified polymorphic DNA (RAPD) polymerase chain reaction to characterize individual Lucilia sericata Meigen from southern England was evaluated. Some simple techniques which allowed the preservation and extraction of DNA to be optimized without the complications of transporting liquid nitrogen were investigated. The RAPD results show that closely related L. sericata, including those from a single strike, can be readily distinguished from each other on the basis of their RAPD profiles resolved using electrophoretic analysis; profiles were defined with ten random primers. Analysis of these RAPD data using a similarity coefficient method and a recently developed randomization test to detect the non-random association of alleles at different loci, allowed the genetic homogeneity of L. sericata within southern Britain to be explored. This study shows that while a number of factors can complicate the use and interpretation of RAPD fragments as genetic markers, RAPD fingerprinting can be a valuable technique for studies of intraspecific genetic variation in L. sericata.
The residual Toxicity of DDT to Bed-bugs (Cimex lectularius, L.)
Authors: Barnes Sarah
Published: July 2009

The investigations herein recorded show that DDT is more toxic to bed-bugs when available on a surface as an oil solution than as a dry film, and that the toxicity of the latter is determined to some extent by the volatility of the medium in which DDT is applied. The results of trials on filter paper, glass and unpainted wood suggest that the minimum period of exposure to a dry film of DDT necessary for the insect' to acquire a lethal dose is one hour, and that this critical period is constant irrespective of the nature of the DDT-treated material to which the insect is exposed. Tests with bugs on DDT-impregnated filter paper show that this period can be curtailed considerably by the addition of a fine oil spray.
The Mosquitoes of Bwamba County, Uganda. III.—The vertical Distribution of Mosquitoes in a Banana Plantation and the biting Cycle of Aëdes (Stegohyia) simpsoni, Theo.
Authors: Haddow A. J.
Published: July 2009

1. The work here reported was carried out in Bwamba County, Uganda, a district where human yellow fever has recently occurred. It consisted of continuous 24–hour catches of biting mosquitoes in a banana plantation, made simultaneously at ground level, 6 ft., 12 ft. and 18 ft.

2. Aédes (Stegomyia) simpsoni, Theo., the carrier of human yellow fever in Bwamba, was found to be active throughout the day at all these levels.

3. The presence of sylvan mosquitoes in the banana plantation was noted. The nearest forest was ½ mile away.

4. The biting cycle of the strictly diurnal A. simpsoni was studied, and it was found that this species was most active on warm cloudy days. The main factors decreasing its activity appeared to be cold, wind, and direct hot sunshine.
Notes on the Bionomics of Hieroglyphus nigrorepletus, Bolivar (Orthoptera, Acrididae) at Benares, United Provinces, India
Authors: Roonwal M. L.
Published: July 2009

Since the recognition by Bolivar (1912) of Hieroglyphus nigrorepletus as a distinct species, Coleman's (1914) note and Uvarov's (1922) valuable revision of the rice grasshoppers, it has been clear that in the earlier literature this species has been confused with H. banian, F., chiefly under the name of H. furcifer, Serv., while H. bettoni, Kirby, 1914, and H. vastator, Carl. 1916, are synonyms.
Biochemical Differences between the solitary and gregarious Phases of Locusts and Noctuids
Authors: Matthée J. J.
Published: July 2009

The theory of phases, Uvarov (1921), had the object of explaining the interrelationship between different forms ofLocusta migratoriaandLocustana pardalina. This theory has been accepted by most entomologists working on locust problems. Authors such as Faure (1923 and 1932), Johnston and Maxwell-Darling (1931) and later a series of others including Hussein and Ramchandra Rao, proved and confirmed the truth of Uvarov's theory.
The Action of the Systemic Insecticide Systox, on Aphids
Authors: David W. A. L. , Gardiner B. O. C.
Published: July 2009

The work described in this paper has been carried out with two proprietary samples, designated Systox 50 emulsion and E 1059, of a systemic insecticide of which the active ingredient, subsequently referred to throughout as Systox, is a mixture of O,O-diethyl O-ethylmercaptoethyl thiophosphate and its isomer, O,O-diethyl S-ethylmercaptoethyl thiophosphate.

The samples were tested against Aphids for contact and systemic action.

It is concluded that, as a contact insecticide against Aphis fabae Scop, on broad beans, Systox is about equitoxic with paraoxon and so more toxic than schradan and dimefox.

Systox is readily absorbed by the roots of broad bean and cabbage plants from soil, sand and aqueous solutions and the translocated material is very effective as an insecticide against A. fabae on broad bean, and Myzus persicae (Sulz.) and Brevicoryne brassicae (L.) on cabbage.

Applied in this way, Systox is more effective than schradan, dimefox and paraoxon, and about equal to the most toxic compound previously tested, sodium fluoroacetate.

An experiment by the cut tap-root technique confirms these conclusions. A dose of 1 mg. of Systox per kg. of fresh bean-plant tissue gave a complete kill of A. fabae by the 10th day. The same amount of sodium fluoroacetate had previously been shown to give a complete kill in three days.

The plants were carefully watched for signs of damage during the tests. It was concluded that there was a considerable margin between the insecticidally effective and the phytotoxic concentrations.

Systox is also translocated from older to younger leaves of bean and cabbage plants and it may reach concentrations sufficient to kill the Aphids feeding on the untreated leaves. This effect was more consistently obtained in the broad bean than in cabbage plants. In both cases, however, the results were variable.

Solutions of Systox exert a direct fumigant action on Aphids, but there is little evidence that toxic material is transpired by treated plants.
The Action of the Systemic Insecticide Systox, on Pieris brassicae (L.) and Phaedon cochleariae (F.)
Authors: David W. A. L. , Gardiner B. O. C.
Published: July 2009

The mixture of O, O-diethyl O-ethlmercaptoethyl thiophosphate and O, O-diethyl S-ethylmercaptoethyl thiophosphate, known as Systox, which has been previously tested against Aphids, has now been tested as a systemic insecticide against the eggs and larvae of Pieris brassicae (L.) and the eggs, larvae and adults of Phaedon cochleariae (F.).

Systox is toxic by direct contact to all stages of these insects but is much less effective in this way than diethyl p-nitrophenyl phosphate (paraoxon).

As a systemic insecticide applied to the roots of teh host-plant, Systox again acts on all stages of the insects (except the eggs of Phaedom), but, compared with the dose which killed Aphids, about twice as much is required to kill Phaedon larvae and between 20 and 100 times as much to kill Pieris larvae, depending on the method employed.

When applied systemically Systox, like paraoxon, can prevent the emergence of Pieris larvae from the eggs.
A Method for estimating Populations and counting large Numbers of Aphis fabae Scop
Authors: Banks C. J.
Published: July 2009

A method for estimating population changes of Aphis fabae Scop. on bean plots is described. This involved the classification of bean stems in the field according to five arbitary classes of infestation and the removal to the laboratory of ten samples of each class of infested stem for the estimation of their Aphid numbers. A simple volumetric method for counting large numbers of A. fabae is described and the results obtained from three bean plots are presented.
Notes on Pseudendaphis maculans Barnes, a Cecidomyid Endoparasite of Aphids in Trinidad, B. W. I.
Authors: Kirkpatrick T. W.
Published: July 2009

An account is given of the life-history of Pseudendaphis maculans Barnes, a common and widely distributed endoparsite of Aphids, especially of Toxoptera aurantii (Boy.), in Trinidad. Alates are parasitised to a much smaller extent than apterae : it is thought that this is due to the parasite larva inhibiting wing development. Nymphs appear to be attacked usually during the first stadium; the parasite larva is fully fed after 6 to 7 days. Shortly before the larve leaves its host the latter assumes a characteristic spotty appearance, due to numerous granules of dark matter that are readily visible through the integument, which has become paler and more transparent than normal. Pupation takes place in the soil: 9–10 days after leaving the host the adult emerges, invaribaly during the early afternoon.
Observations on the Incidence of Trypanosomes in Glossina palpalis (R.-D.) in Sierra Leone
Authors: Squire F. A.
Published: July 2009

Observations were made in Sierra Leone from September 1949 to November 1951 on the incidence of trypanosomes in Glossina palpalis (R.-D.), in continuation of those previously reported that began in September 1948. Flies were dissected; trypanosomes found to be restricted to the proboscis were classed as Trypanosoma vivax and those found also or only in the mid-gut as T. congolense. None of the flies had infected labial glands. The whole data are presented for the sexes separately by months.

The existence of a marked seasonal variation in the incidence of T. vivax in G. palpalis is confirmed. The highest rates of infection occured in the months of heavy rain, and there was a significant inverse correlation between the monthly means of infection rate and of hours of sunshine. The cause is unknown, but possible explanations are discussed.

The older the fly, as judged by its appearance, the greater the rate of infection by both species of trypanosme; the virtual absence of infection in the youngest group of flies does not support the theory that they can only be infected when very young.

In the case of T. vivax, but not in that of T. congolense, females flies were more heavily infected than males. This may be due to larger food intake by the females, or to males, because of their more active life, appearing to be older than they are.
An experimental study of early stage survival of Helicoverpa armigera (Lepidoptera: Noctuidae) on cotton
Authors: Kyi Aung , Zalucki Myron P. , Titmarsh Ian J.
Published: July 2009

The pattern and cause of mortality of the early stages of Helicoverpa armigera (Hübner) on cotton was investigated in both field and glasshouse situations for two seasons. In 1987, egg losses were high (32–88%) over days 1–3 following oviposition, more so from the lower than upper leaf surface. The mortality of first instar larvae was 93–100% over days 4–5 following oviposition, and losses were higher from seedling stage than squaring cotton. Wind, rain (or watering), aerial predators, dispersal of first instar larvae, and host plant effects (including leaf orientation) were important mortality factors. In 1988 trials, egg losses over days 1 to 3 after oviposition on plants in glasshouse and field situations, respectively, were 0–1% and 5–6% due to changing leaf orientation alone; 4–22% and 16–32% due to rain/watering and changing leaf orientation combined; 14–31% and 12–31% for wind and changing leaf orientation combined; and 4–38% and 23–52% for the combination of wind, rain/watering and changing leaf orientation. Mortality of first instar larvae on day 4 was 32% and 29% on plants in glasshouse and field, respectively, from which the action of such mortality factors had been excluded. Mortality on plants with changing leaf orientation alone was 30% and 68%, with rain/watering and changing leaf orientation combined 48% and 74%; with wind and changing leaf orientation combined 40% and 63%; and with all factors combined 45% and 69%, respectively. The highest losses (of eggs) occurred on day 1 after oviposition, and similarly for first instar larvae on day 4, which coincided with hatching.
Temperature preference in Triatoma infestans (Hemiptera: Reduviidae)
Authors: Lazzari Claudio R.
Published: July 2009

The thermal preference of adults of the reduviid bug Triatoma infestans (Klug) was investigated along a temperature gradient by means of video recording. The preferred temperature varied with a daily rhythm, reaching the highest value at the onset and the lowest at the end of the dark phase. The daily range of preferred temperatures depended on the starvation level. After feeding it was about 28–29°C, and after 12 days of starvation 25–26°C. The number of eggs laid showed a bimodal pattern, with maxima at 29°C and 26°C. Along a gradient of relative humidity, the bugs were always found around 40% r.h.
Population phenology of whitefringed weevil, Graphognathus leucoloma (Coleoptera: Curculionidae), in pasture in a Mediterranean-climate region of Australia
Authors: Matthiessen J. N.
Published: July 2009

In undisturbed annual pasture in a Mediterranean-climate region of Australia adults of the whitefringed weevil, Graphognathus leucoloma (Boheman), were present from summer to early winter (December–June), with upsurge in numbers of first instar larvae only occurring after the rains began in April. The G. leucoloma population was predominantly first instar larvae in high abundance throughout the winter period (May–August). Larval growth, with high mortality, occurred in the spring period (September–January). The survival of eggs during the dry summer when adults were most abundant, although only at times of unseasonal rainfall, indicated that low larval recruitment at that time resulted primarily from the absence of high-quality legume food essential for oogenesis. It was inferred that most larvae arose from heavy oviposition by the few adults present in autumn when rainfall germinated annual legumes. A steady year-round abundance of late-instar larvae indicated that not all individuals completed their development in the one year.
Sampling lepidopterous pests on maize in West Africa
Authors: Schulthess F. , Bosque-Pérez N. A. , Gounou S.
Published: July 2009

The spatial distribution of five lepidopterous pests, Sesamia calamistis Hampson (Noctuidae), Eldana saccharina Walker (Pyralidae), Spodoptera exempta (Walker) (Noctuidae), Mussidia nigrivenella (Ragonot) (Pyralidae), and Cryptophlebia leucotreta (Meyrick) (Tortricidae), on maize in West Africa is described using Taylor's power law and the relationship of proportion of infested plants to the mean density. All five species showed a highly aggregated distribution, with Taylor's indices of aggregation ranging between 1.23 for C. leucotreta and 1.52 for Sesamia calamistis. Enumerative and binomial sampling plans that incorporate Taylor's power law are proposed to estimate mean densities of S. calamistis, C. leucotreta and the species complex consisting of E. saccharina, M. nigrivenella and Spodoptera exempta which showed similar spatial distributions, with a predefined reliability level.
DNA fingerprinting to study spatial and temporal distributions of an aphid,Schizaphis graminum(Homoptera: Aphididae)
Authors: Shufran Kevin A. , Black William C. , Margolies David C.
Published: July 2009

The length of the intergenic spacer in the rRNA cistron varied within and among individuals ofSchizaphis graminum(Rondani). Spacer lengths did not vary among offspring of a single maternal lineage (clone). The intergenic spacer was used as a molecular fingerprinting probe on individual aphids and to study spatial and temporal distributions of clones. A spatially nested sampling design was used in wheat and sorghum to estimate numbers of clones among aphids on leaves, among leaves on plants, among plants in fields, among fields in counties, among counties, and among dates. Each level of nesting added a level of clonal diversity to the entire population. 82.3% of the total population diversity was found among aphids on one sorghum leaf. Sampling additional leaves increased diversity slightly (5.4%), whereas plants (0.9%), fields (0.6% to 3.6%), and counties (1.2%) added very little. Sample dates contributed the highest increase in diversity (11%). Diversity rose and fell in wheat along with aphid numbers but remained constant in sorghum. Little variation in Mahalanobis distances could be explained by geographic distances. No genotypes were unique to any field, county, crop, or year. Kansas populations are made up of a large mixture of genetically diverse clones that recolonize wheat and sorghum each year. Sampling many plants, fields, or counties is an ineffective way to increase clonal diversity. Plant breeders developing crop resistance toS. graminumcan expect plant entries to be exposed to most of the genetic diversity present in Kansas populations regardless of location.
Responses of tsetse flies (Diptera: Glossinidae) to odour-baited trees
Authors: Vale G. A.
Published: July 2009

Field studies in Zimbabwe elucidated how trees might be enhanced as baits for controlling Glossina morsitans morsitans Westwood and G. pallidipes Austen. Catches from electrocuting devices at the bases of trees were near nil when sampling tsetse flies landing on the trunk but much greater when sampling them flying within 1 m of the trunk. Catches increased 5–8 times when 2 m2 of the trunk were blackened and given odour of acetone, 1-octen-3-ol, 3-n-propyl phenol and 4-methyl phenol, but were still only ca. 30% of the catches from an odour-baited, free-standing, 1 × 1 m screen of black cloth. The upright trunk of real and model trees hindered their attractiveness but leaves and branches 5 m above ground had no clear effect. Real and artificial stumps of trees were as effective as the screen if they were 1 m2, compact and sharply outlined. The practical and biological implications of the results are discussed, with particular reference to the use of insecticide-treated netting with modified tree stumps as baits for control.
Avermectin residues in sheep and cattle dung and their effects on dung-beetle (Coleoptera: Scarabaeidae) colonization and dung burial
Authors: Wardhaugh K. G. , Mahon R. J.
Published: July 2009

Data from dung-baited pitfall traps show that dung beetles (Coleoptera: Scarabaeidae) do not discriminate against dung from sheep or cattle treated with avermectin. On the contrary, for a period post-treatment, dung from animals treated with avermectin attracted more beetles than dung from untreated animals. This effect was more marked with cattle dung than with sheep dung. The period of enhanced attractiveness of sheep dung was restricted to dung produced during the first day after treatment, whereas with cattle dung, the effect was still evident in faeces produced 25 days after treatment. Cattle dung produced from 3–25 days post-treatment caused 100% mortality in newly hatched larvae of the bushfly,Musca vetustissimaWalker (Diptera:Muscidae). In dung of day 35, mortality was 93.6%. Dung collected from sheep from 1–6 days after treatment also caused 100% mortality of fly larvae, but by day 28, no toxic effects were detectable. Field observations on the colonization of cattle pats confirmed the enhanced attractiveness of dung from treated animals and suggested that departure rates from treated dung were lower than those from untreated dung. Treated pats supported higher beetle populations than untreated pats and burial was more rapid. The potentially serious implications of the enhanced attractiveness of avermectincontaminated dung are discussed in relation to the survival of dung beetle communities.
Colony dispersion and nesting habits of the ants, Dolichoderus thoracicus and Oecophylla smaragdina (Hymenoptera: Formicidae), in relation to their success as biological control agents on cocoa
Authors: Way M. J. , Khoo K. C.
Published: July 2009

In mixed cocoa-coconut palm plantations in Malaysia the palm spadices provide large, stable nesting sites for Dolichoderus thoracicus (Smith) in contrast to impermanent sites on cocoa and on the ground. D. thoracicus and the arboreal leaf-nesting Oecophylla smaragdina (Fabricius) both benefit from the mixed system which also provides a more stable food supply from honeydew-producing Homoptera. A scoring method showed that about 50–200 O. smaragdina or 200–2000 D. thoracicus on a cocoa tree can protect it effectively from Helopeltis theobromae Miller (Hemiptera: Miridae). The relatively greater efficiency of O. smaragdina as a biological control agent is associated with its actively dispersive predatory behaviour in contrast to the localized concentration of D. thoracicus workers at sites such as cocoa pods where it tends honeydew-producing Homoptera, and where it acts largely by deterring H. theobromae. Despite its biological control potential, the painfully biting O. smaragdina, unlike D. thoracicus, is normally considered unacceptable to plantation staff. Nevertheless it should be recognized as valuable in integrated pest management of cocoa pests especially where D. thoracicus is difficult to establish.
Preliminary List of the Acari occurring on the Brown Rat (Mus norvegicus) in Great Britain, with the description of a New Species (Haemogamasus oudemansi)
Authors: Hirst Stanley
Published: July 2009

The English specimens listed below were captured on wild examples of the brown rat by the author, and those from Scotland by Waterston. Several of these mites have already been recorded by Dr. A. C. Oudemans and other authors as occurring on this host. Only three of the species (Laelaps echidninus, Notoedres muris and Myobia ensifera) can be regarded with certainty as being practically restricted to Mus norvegicus, but this is possibly also the case with Haemogamasus oudemansi, which so far has only been found on this host. The other species are frequently found on other mammals or in their nests, especially in that of the mole (see Oudemans, Acarologisches aus Maulwurfsnestern, Arch. Naturg. Berlin, 1913).
New Culicidae from Borneo and Hong Kong
Authors: Edwards F. W.
Published: July 2009

The following nine new species of Culicidae have recently been received by the Imperial Bureau of Entomology; the types have been presented to the British Museum.
The Anopheles of Malaya.—Part II.
Authors: Stanton A. T.
Published: July 2009

This species was first described by Dönitz from specimens taken in Sumatra. About the same time Theobald had prepared from Malayan specimens the description of an Anopheline species for which he proposed the name ocellatus, but recognising that Dönitz' kochii and his own ocellatus were the same species he published his description as that of Anopheles kochii, Dönitz.
Australasian Hispidae of the Genera Bronthispa and Promecotheca which destroy Coconut Palm Fronds
Authors: Froggat Waltes W.
Published: July 2009

With the increasing demand for copra all over the world for the production of coconut oil, the cultivation of coconut palms has increased enormously during the last ten years in the Solomon Islands, New Britain, Papua, Samoa, and the New Hebrides, and large areas of virgin forest have been cleared and planted on regular scientific principles. In olden times most of the nuts were collected from the native plantations, where the palms were grown under almost wild forest conditions, arid were then more hardy and did not suffer to the same extent from insect pests as do the palms planted under modern conditions. It is probable that the increased food supply, represented in the fronds of the thousands of young coconut palms planted out, has been responsible for the enormous increase of a number of indigenous leafeating beetles, which, under the conditions previously prevailing, lived upon the wild coconut and other species of palms growing in the jungle. In addition to many insect pests allied to or identical with those known in Ceylon, India, and the Malay States, we have in these Eastern islands a number of leaf-destroyers in the small flattened beetles belonging to the family Hispidae. The larvae of these beetles feed either on the upper surface, or in the tissue of the leaf under the protection of which they finally pupate, so that one can sometimes obtain the whole life-history from the egg to the perfect insect in a single palm frond. The majority of these leaf beetles, which are causing so much damage in the coconut plantations, belong to the genus Protnecoiheca, Blanchard, and from what we know of the life-history of several species that have become serious pests, it is fairly safe to assume that the habits of all the species are similar.
Two New Species of Fruit Flies from Southern India
Authors: Bezzi M.
Published: July 2009

Very nearly allied to B. scutellaris, Bezzi (Memoirs of the Indian Museum, iii, 1913, p. 98, pl. viii, fig. 10), but differing in its smaller size, black face, differently coloured scutellum and unicolorous wings. This last character distinguishes it at once from any other Oriental species of this genus at present known.
Descriptions of five New Species of Anoplura and Mallophaga
Authors: Cummings Bruce F.
Published: July 2009

The following systematic work was carried out in the Entomological Department of the British Museum and is based on material in the National Collection. An endeavour has been made to extend the area of the field usually covered by the systematist in his search for characters, although the author ia well aware how far short of the ideal in this matter the paper falls. The species described are:—
A Note on Pseudaonidia fossor, Newst
Authors: Rutherford A.
Published: July 2009

In January 1912, the writer collected in Trinidad, B.W.I., what is in all probability Pseudaonidia fossor, Newst. (Bull. Ent. Research, iv, p. 308, 1914). The insects occurred on the twigs of a plant that has been determined as Ficus comosa. The leaves of the same plant were heavily infested on the under surface by what is probably Aspidiotus personatus, Comst.
A proposal for the development of a world-wide biological control organisation
Authors: Wilson F.
Published: July 2009

It has been proposed that the existing Organisation Internationale de Lutte Biologique (a mainly western European and Mediterranean body) should be enlarged and restructured to form a world-wide International Organisation for Biological Control. IOBC would be open to individual as well as institutional members, and would have largely autonomous regional sections in different parts of the world. IOBC is expected to come into being early in 1971.
Studies in West Pakistan on the biology of one Nitidulid species and two Coccinellid species (Coleoptera) that attack scale insects (Hom., Coccoidea)
Authors: Ahmad Rafiq
Published: July 2009

One Nitidulid species,Cybocephalus semiflavusChamp, and two Coccinellid species,Chilocorus nigritus(F.) andSimmondsius pakistanensisRafiq Ahmad & Ghani, commonly attack Diaspididae in West Pakistan. The known distribution and prey of each species are reviewed, and new records from West Pakistan given. The immature stages are described.

The development ofCybocephalus semiflavusfrom egg to adult was completed in 37–41 days atc. 26°C. Mating occurred 3–5 days after emergence and oviposition began 3–6 days later, 15–69 eggs being laid. An individual adult could consume up to 47 Diaspidid eggs daily, but all Diaspidid stages were attacked. In the field the predator persisted at low prey densities, but onAonidiella orientalis(Newst), the preferred prey, its population rose in proportion to that of its prey.

The development ofS. pakistanensistook 32–41 days from egg to adult atc. 24°C when fed onA. orientalisandQuadraspidiotus perniciosus(Comst). Mating was 8–11 days after emergence and oviposition began 6–11 days later, 153–242 eggs being laid. An individual could consume up to 35Leucaspis coniferarum(Hall & Williams) daily. The predator was abundant during April-May, but later its effect was limited byTetrastichus epilachnae(Giard).

Atc. 24°CChilocorus nigrituscompleted development from egg to adult in 33–40 days. Mating was 4–7 days after emergence, and oviposition began 8–13 days later, 228–351 eggs being laid.C. nigritusattacked several species of Diaspidids, an individual consuming up to 41 scales daily. The adults congregated on banyan trees during November-March in the coastal area and during September-June in the foothills, but dispersed to scale-infested plants at other times of year.
The effect of particle size on the contact toxicity of insecticides to adult mosquitoes, Anopheles stephensi List
Authors: Hadaway A. B. , Barlow F. , Turner C. R.
Published: July 2009

The optimum size range of particles of two carbamates and two organophosphorus compounds in deposits on plywood and plaster for contact toxicity to blood-fed females of Anopheles stephensi List, was 5–30 µm. The effect of particle size on the contact toxicity of these compounds of high intrinsic toxicity was not great and in this respect resembled that found previously for dieldrin and γBHC. In the few tests done, the concentration of active ingredient in wettable powder formulations was not an important factor in determining the contact toxicity of deposits of such toxic materials.
Ecological notes on species A and B of the Anopheles gambiae complex in the Kisumu area of Kenya
Authors: Service M. W.
Published: July 2009

During November and December 1969, larvae and adults of the Anopheles gambiae complex from the Kisumu area of Kenya were identified by cytogenetical methods as species A and B. There appeared to be no difference between their choice of larval habitats. Although adults of both species were common in village huts, species B comprised 80·6% of the exophilic population. Adults of both species caught from huts and out of doors had fed predominantly on bovids; the incidence of human feeds was below 40%. The impact of residual insecticidal house-spraying would depend on the relative sizes of the endophilic and exophilic populations of species B.
The mealybugs (Homoptera, Coccoidea, Pseudococcidae) of sugar-cane, rice and sorghum
Authors: Williams D. J.
Published: July 2009

The taxonomy of 39 species of mealybugs (Pseudococcidae) attacking sugar-cane, rice and sorghum is discussed. Twenty-seven species are described, eight of them as new. Some aspects of the biology derived from the literature are added, together with a key to the 39 species, and host and distribution records of each.
Esterase variation and squash induction in B-type Bemisia tabaci (Homoptera: Aleyrodidae)
Authors: Byrne Frank J. , Bedford Ian D. , Devonshire Alan L. , Markham Peter G.
Published: July 2009

Polyacrylamide gel electrophoresis was used to study esterase variation in a population of B-type Bemisia tabaci (Gennadius). A total of six esterases was identified within an overall B-type pattern. However, both qualitative and quantitative variation in some of these esterases gave three clearly defined phenotypes. One of these lacked esterase E0.14 which until now has been the key band used to classify B-type strains electrophoretically. A strain homozygous for the E0.14 null allele (B-Null) retained the ability to induce squash silverleaf, a plant physiological disorder which hitherto has only ever been associated with whitefly strains possessing this band.
Pyrethroid and organophosphate resistance in the tobacco whitefly Bemisia tabaci (Homoptera: Aleyrodidae)
Authors: Cahill Matthew , Byrne Frank J. , Gorman Kevin , Denholm Ian , Devonshire Alan L.
Published: July 2009

Eleven strains of Bemisia tabaci (Gennadius), including a laboratory susceptible strain, were bioassayed as adults with three organophosphorus (OP) insecticides, three pyrethroids and one OP/pyrethroid combination. The contemporary strains were from diverse geographical areas and hosts and included examples of the A-, B-, and non-B-biotypes. All recent collections were multi-resistant to these insecticides which have been used extensively for their control. The patterns of cross-resistance for the OPs were clear but less so for the pyrethroids. All populations that resisted profenofos and cypermethrin also resisted the combination of profenofos and cypermethrin. Although the importance of selection pressure on levels of resistance was not easily quantifiable the highly selected populations exhibited the highest levels of resistance. The significant within, as well as between, biotype variation in resistance factors clearly indicated that insecticide resistance and biotype were not directly related. The roles of acetylcholinesterase sensitivity and general esterase activity in resistance to OPs and pyrethroids are discussed.
Clonal variability in the response of Sitobion avenae (Homoptera: Aphididae) to resistant and susceptible wheat
Authors: Caillaud Claudia M. , Dedryver C.A. , Di Pietro J.P. , Simon J.C. , Fima F. , Chaubet B.
Published: July 2009

The development and reproduction of 60 clones of Sitobion avenae (Fabricius), collected in the Rennes Basin, were compared on a resistant Triticum monococcum (Linnaeus) line (Tm44) and a susceptible Triticum aestivum (Linnaeus) cultivar (Arminda). All clones had lower larval survival and mean fecundity when reared on Tm44 in comparison with Arminda. They all performed equally well on Arminda whereas there was a marked and continuously distributed variation in performance parameters among clones maintained on Tm44. The plant species, from which clones originated, significantly affected aphid performances on resistant Tm44. A more detailed experiment was carried out with four clones, shown to differ in their level of fitness on Tm44. Their performances were compared on resistant (Tm44 and Tm46) and susceptible (Tm47 and Arminda) wheat genotypes. On the basis of larval development time and intrinsic rate of natural increase (rm), two types of response were distinguished among the four clones: clones Sa1 and Sa39 appeared to be less affected by Tm44 and Tm46 resistance than Sar2 and Sa48. Moreover, Tm46 was much less resistant to clone Sal than was Tm44. These results are discussed in relation to the origins of the variation in performance of S. avenae on resistant wheat, and their implications in plant breeding for resistance to S. avenae.
The phenology ofBemisia tabaci(Homoptera: Aleyrodidae) populations on cassava in southern Côte d'Ivoire
Authors: Fishpool L. D. C. , Fauquet C. , Fargette D. , Thouvenel J.-C. , Burban C. , Colvin J.
Published: July 2009

Population phenologies of the whitefly,Bemisia tabaci(Gennadius) (Homoptera: Aleyrodidae), in young cassava crops in Côte d'Ivoire, West Africa, are described for three field seasons. Populations of all stages were consistently greatest 6–12 weeks after the crop was planted. The number of adults on plants as well as on attractive and non-attractive sticky traps displayed cycles of buildup and decline each year, the periodicity of these cycles corresponding to the generation time ofB. tabaciunder field conditions. Adult population declines were probably caused by emigration from the crop. Rainfall was negatively correlated with both nymph and adult populations, possibly due to reduced oviposition after rain.B. tabaciis the vector of African cassava mosaic geminiviruses (ACMV) and the observedB. tabacipopulation trends fit well with the pattern of ACMV buildup in the crop.
Insecticide susceptibility status in individual species of the Anopheles gambiae complex (Diptera: Culicidae) in an area of The Gambia where pyrethroid impregnated bednets are used extensively for malaria control
Authors: Hemingway J. , Lindsay S.W. , Small G.J. , Jawara M. , Collins F.H.
Published: July 2009

Pyrethroid-impregnated bednets are being used nationwide in The Gambia. The future success of this malaria control programme depends partly on the vectors remaining susceptible to those insecticides used for treating the nets. The present study was carried out on the south bank of the river Gambia, during the first large scale trial of nets in this country. Thus this area represents a sentinel site for detecting insecticide resistance in local vectors. This study gives an example of how a system of early detection for resistance problems can be set up in a relatively complex situation where multiple vectors and non-vectors are present. Samples of the Anopheles gambiae complex were caught indoors using light traps in twelve villages used in the bednet study. In all villages A. gambiae sensu stricto Giles was the predominant member of the complex as determined using the rDNA-PCR diagnostic assay. Limited bioassays with DDT and permethrin, and biochemical assays for a range of insecticide resistance mechanisms suggest that the A. gambiae complex remains completely susceptible to all major classes of commonly used insecticides including pyrethroids. Biochemical assays suggest that a low frequency of DDT resistance may occur in A. melas Theobald. This is based on elevated glutathione S-transferase levels coupled with increased levels of DDT metabolism and does not involve cross-resistance to pyrethroids. Therefore we do not envisage a decline in the efficacy of treated nets against malaria vectors in the study area in the immediate future, although monitoring should be continued whilst wide-scale use of impregnated bednets is operational.
Spatial patterns of the parasitic mite Hemisarcoptes coccophagus (Astigmata: Hemisarcoptidae): host effect, density-dependence of aggregation, and implications for biological control
Authors: Izraylevich Sergey , Gerson Uri
Published: July 2009

The spatial distribution of the parasitic mite Hemisarcoptes coccophagus Meyer on two armoured scale insects (Homoptera: Diaspididae) was highly aggregated in the field. Mites were more aggregated on young than on ovipositing host scale females. No differences in the mite's distribution pattern were found between latania scale (Hemiberlesia lataniae (Signoret)) and oleander scale (Aspidiotus nerii (Bouché)). Mite aggregation was density-dependent on ovipositing host females (the degree of overdispersion decreased as mite abundance increased), but density-independent on young females. The effect of density-dependent and independent mite aggregation on the proportion of hosts escaping attack at different parasite abundances was simulated, and its relevance to biological control of Diaspididae is discussed.
A trial of a cypermethrin ‘pour-on’ insecticide to controlGlossina pallidipes, G. fuscipes fuscipesandG. morsitans submorsitans(Diptera: Glossinidae) in south-west Ethiopia
Authors: Leak S.G.A. , Mulatu Woudyalew , Rowlands G.J. , D'Ieteren G.D.M.
Published: July 2009

Tsetse populations and trypanosome prevalence in cattle were monitored from 1986 to 1993 in the Ghibe valley, south-west Ethiopia. From January 1991 to December 1993 between 2000 and 4000 cattle were treated at monthly intervals with a synthetic pyrethroid insecticide, cypermethrin (RS-alpha-cyano-3-phenoxy- benzyl [1RS]-cis, trans-3-[2,2-dichlorovinyl]-2,2-dimethylcyclopropane carboxylate). An approximate dosage of 1 ml per 10 kg bodyweight was used to control tsetse flies (Glossinaspp.). Treatments were given as ‘pour-on’ applications along the backlines of animals, using automatic drench-gun applicators. This resulted in a decline of 93% in the apparent density ofG. pallidipesAusten. A reduction of 83% in the apparent density ofG. morsitans submorsitansNewstead was also observed. This reduction was associated with a reduction in trypanosome prevalence in cattle of over 74% in 1993, despite a high level of resistance to all available trypanocidal drugs. The numbers ofStomoxysspp. (Diptera: Muscidae) and Tabanidae were also significantly reduced (P < 0.01).