bluuebunny/crossref_metadata_2025_split huggingface dataset:
Introduction and establishment of baculovirus for the control of rhinoceros beetle Oryctes rhinoceros (Coleoptera: Scarabaeidae) in the Andaman Islands (India)
Authors: Jacob T.K. 
Published: July 2009

AbstractThe Kerala isolate of Oryctes baculovirus (OBV-KI) was introduced into the Andaman Islands in May 1987 for the population suppression of Oryctes rhinoceros (Linnaeus). The virus was released initially at four locations along the island chain. In all the places of virus release, damage to coconut palms was reduced by about 90% within 43 months of release. At one place of virus release, Sipighat, the adult beetle population in the field was reduced by 80% within 18 months and by 96% by the end of 55th month of release. Sixty per cent of the adult beetle population in the field showed symptoms of infection 30 months after virus release. The decline in the numbers of breeding sites at Viper Island and Sipighat were 100% and 98% respectively at the end of 43 months of virus release. The rate of spread of the virus in the field was estimated to be about 1 km/month. The beetle population remained at low levels after the establishment of the virus in these islands.
The unusual occurrence of savanna members of the Simulium damnosum species complex (Diptera: Simuliidae) in southern Sierra Leone in 1988
Authors: Thomson M.C. , Davies J.B. , Post R.J. , Bockarie M.J. , Beech-Garwood P.A. , Kandeh J. 
Published: July 2009

AbstractAll available identifications of sibling species of the Simulium damnosum complex in southern Sierra Leone for the years 1983–1987 have been analysed for any evidence that they might provide on whether the appearance of S. sirbanum in this area in 1988 is indicative of a gradual southerly extension of range, or a unique occurrence. No evidence was found to suggest a long-term immigration trend over the five years prior to 1988, and the latter of the two possibilities is the more likely. No meteorological or other factors are known that might account for the sudden appearance of S. sirbanum in southern Sierra Leone in 1988, but the possible causes of such immigration into forested parts of West Africa and their epidemiological implications for human onchocerciasis in the region are briefly discussed.
Factors affecting the response ofLongitarsus jacobaeae(Coleoptera: Chrysomelidae) to upwind plant odours
Authors: Zhang Zhi-Qiang , McEvoy Peter B. 
Published: July 2009

AbstractFactors (developmental state, starvation time, host local density and host distance from insects) affecting the response of the ragwort flea beetle,Longitarsus jacobaeae(Waterhouse), to upwind plants of tansy ragwort,Senecio jacobaeae(Compositae), were examined in a wind tunnel. There was seasonal variation in beetle response to host odours. Individuals collected during spring and early summer (6 May to 14 July 1993) showed directed movement toward the upwind plants. However, individuals collected in mid-summer (23 July 1993) showed no significant response to upwind host plants and walked randomly in the wind tunnel. Individuals collected during late summer to autumn (4 August to 23 October 1994) once again showed response to upwind plants, whereas those collected in winter (January 1994) walked randomly in the wind tunnel. The absence of beetle response to plant odours coincided with potential summer aestivation and winter ‘hibernation’. For spring and early summer beetles that responded to plant odours, the strength of the response did not change significantly with the number of plants (1, 2, 4 or 6) presented upwind in the tunnel nor with the starvation time (2, 6, 10, 12, 24 or 36 h) of the tested beetles, and these patterns were consistent for male and female beetles. Individuals responded to plants from a distance of 60 and 300 cm. The speed of movement, similar for males and females, increased slightly asL. jacobaeaeoriented more directly toward host plants.
Studies on age and trypanosome infection rate in females of Glossina pallidipes Aust., G. palpalis fuscipes Newst. and G. brevipalpis Newst. in Uganda
Authors: Harley J. M. B. 
Published: July 2009

During 1964–65, 1,646 newly emerged females of Glossina pallidipes Aust., 1,898 of G. palpalis fuscipes Newst. and 2,528 of G. brevipalpis Newst. were marked and released in an area on the north-eastern shore of Lake Victoria in Uganda so that, by examination of those subsequently recaptured, the relation between physiological and calendar age could be determined. In the light of the results, records of physiological age and trypanosome infections in large numbers of wild-caught females of the same three species caught in the same area in 1962–63 were examined, together with published observation on the animals on which they fed, and the effects of age and food-animals on the incidence of infections were investigated.Physiological age was determined by examination of the reproductive system and was expresses as the exact or approximate number of ovulations that had taken place. Infections with Trypanosoma were classified as brucei-type, vivax-type or congolense-type, and the last two as mature (infective) or immature, according to the sites in which trypanosomes were found in the flies. All brucei-type infections were regarded as mature.The relation between physiological and calender age indicated that the length of the ovulation cycle was 11 days in G. pallidipes, 11 1/2 in G. brevipalpis and about 15 in G. palpalis fuscipes, but from other evidence that the last figure should have been about 11 days it is considered that ovulation was retarded in the released females of G. palpalis fuscipes.The incidence of mature vivax- and congolense- type infections rose with age in all three species, beginning for the most part when flies were about a fortnight old. Brucei-type infections were rare and were found only in flies more than about 35 days old; nearly all flies with such infections also had one or both of the other types. The incidence of immature vivax-type infections rose with age up to about 25 days and then levelled off, which suggests that all eventually became mature. Immature congolense-type infections were rare.G. pallidipes had the highest total infection rate and G. brevipalpis the lowest. The percentage of order flies in the samples was, however, greater in the later than in G. palpalis fuscipes, which suggests that age is not the sole factor determining infection rate. Food-animals appeared to influence it, since the infection rates of the three species were proportional to the percentages of meals obtained from Bovids.The age at which females were inseminated was lowest in G. palpalis fuscipes, greatest in G. pallidipes and intermediate in G. brevipalpis. Abnormal ovulation cycles were rare in wild-caught flies, and few females that from their age should have been pregnant were found with an empty uterus.
Development of a changed response in Lucilia cuprina (Wied.) to organophosphorus insecticides in New South Wales
Authors: Shanahan G. J. 
Published: July 2009

Since 1956, samples of Lucilia cuprina (Wied.) from many parts of New South Wales have been tested annually for signs of resistance to organophosphours insecticides, which are used there to prevent fly-strike in sheep. For tests, 0.1 μg. diazinon per fly was applied topically; this discriminating dose was twice that required to kill 100 per cent. of susceptible flies. In 1965, some of the flies in a sample from Dubbo, in central-western N.S.W., survived the discriminating dose. Sensitivity tests of the progeny of the survivors (DB strain) and of a normal susceptible strain revealed that the LC50 of the DB strain was about three times that of the normal one. Further tests established that a roughly similar change in sensitivity had ocurred to other diethoxy (dichlofenthion, fenthion-ethyl, bromophos-ethyl, parathion) and to dimethoxy (fenchlorphos, parathion-menthyl, bromophos) organophosphors compounds. The change was therefore non-specific and, since it was also small, is regarded as an example of tolerance rather than of resistance.Subsequent field surveys in 1965–66 showed that tolerance of L. cuprina to diazinon was widespread in N.S.W. The possibility that resistant strains will be selected out by continued use of organophosphorus insecticides is discussed.
The nutritional state of tsetse flies from different vegetation types in Rhodesia
Authors: Bursell E. 
Published: July 2009

The nutritional state of males of Glossina morsitans Westw. (subsp. orientalis Vanderplank) obtained by two different methods from four vegetation types at two contrasted seasons during 1964–65 in Rhodesia was assessed by determining their fat content, haematin content and size. The results showed that even in the hot dry season, when Brachystgia and Commiphora woodlands were leafless, the nutritional state was better in flies from these two vegetation types than in those from evergreen riverine fringe vegetation; in the rainy season, the difference persisted but was smaller. Only in Combretum bushland, which is sparsely wooded, did the poor nutritional state of flies caught in both seasons accord with the relatively inhospitable appearance of this vegetation type.The total food-reserves (fat plus the fat-equivalent of haematin) were higher in flies captured on fly-rounds than in those captured on bait-oxen, but the difference was smaller in populations under nutritional stress, e. g., in flies from riverine fringe vegetation and Combretum bushland in the hot season, which suggests that the period of sexual appetitive behaviour in males is shortened under conditions of nutritional stress.The implications of these results are discussed in relation to methods of control that involve discriminating between parts of the tsetse habitat.
Observations on the biology and taxonomy of the eggs of Anopheles mosquitos
Authors: Hinton H. E. 
Published: July 2009

A study of the egg shells of 11 species of Anopheles was made with the stereoscan electron microscope. A number of structures have been found that are useful in distinguishing between eggs of different species; all of them can also be seen with the light microscope. A list is given of these structures, together with others already known to be of taxonomic importance.The functional significance of the network of the outer layer of the chorion of Anopheles eggs is discussed. It is suggested that the film of gas held by the network is of selective advantage in that it contributes to the buoyancy of the egg, provides it with a part of its protective coloration, and functions as a plastron when the egg is submerged. The plastron of A. labranchiae atroparvus Van Thiel resisted wetting at an excess pressure of more than half an atmosphere.The relation of Anopheles eggs to the surface film is discussed. A highly stable line of contact with the water is formed, such that the water surface is depressed along the sides of the egg and raised at each end. Because like menisci are attracted and unlike ones repelled, eggs make contact with each other end to end or side to side, never end to side. Water spreads on most natural objects, forming menisci like those at the ends of the egg, which is thus provided with anautomatic trapping device that tends to attach the egg endwise to an object projecting from the water. The selective advantage of endwise over sideways attachment is not known, but it may facilitate hatching.The structure of the egg of A. pseudopunctipennis Theobald has been disputed, and it is therefore described in some detail.
A possible genetic method for the control of insect pests, with special reference to tsetse flies (Glossinaspp.)
Authors: Curtis C. F. 
Published: July 2009

The use of chromosome translocations for the control of pests, with particular reference toGlossina, is proposed. A translocation arises if two non-homologous chromosomes in the same cell undergo breakage and the fragments re-join with the wrong partners. At meiosis in an individual heterozygous for a translocation, gamete nuclei with several different combinations of chromosomes are produced. Some of these are diploid for one part and lack completely another part of the normal chromosome set; when such unbalanced gametes fertilise normal gametes inviable embryos are produced. It has been found in a number of organisms that about half the gametes of translocation heterozygotes are of the unbalanced type and such heterozygotes are described as semi-sterile. If an individual inherits the same translocation from both parents it is described as a translocation homozygote; this is often inviable but, if not, its fertility is usually normal.Adult males ofG. austeniNewst. have been irradiated and each of their progeny are being screened for the occurrence of semi-sterility. Any individuals found to be semi-sterile would probably be translocation heterozygotes and their progeny will be inbred to try to produce a viable stock, homozygous for a translocation. If this can be done, large numbers of such translocation homozygotes could be reared and released into a wild population, where matings with wild types would produce heterozygotes, and hence a reduction in the fertility of the population.Using simple assumptions, the effects of releasing translocation homozygotes were computed. Provided the numbers released were such that the translocation frequency approached the optimum value of 50 per cent., the reduction in population fertility would be prolonged for many generations after the releases had finished. It is shown that it would be more efficient to release the translocation homozygotes at successive generations rather than all at once and that the homozygotes released could with advantage be of both sexes. For this reason, and because of the prolonged effect of releases of translocations, it is concluded that the number of individuals that would have to be reared to achieve a given result by the translocation method might be considerably less than if the sterile-male method was used. However, the reduction in population fertility at each generation that can be achieved with the translocation method is limited, and the method would therefore be ineffective against populations whose size was strongly buffered by density-dependent factors.
Studies on the chemical control of wireworms (Agriotes spp.) III.—The direct and residual effects of BHC, aldrin and dieldrin
Authors: Raw F. , Lofty J. R. , Potter C. 
Published: July 2009

To find out if it were possible to reduce wireworm populations by means of seed dressings which are convenient to use, and desirable in other ways, the direct and residual effects of insecticides on wireworms (Agriotes spp.) attacking spring-sown and winter-sown wheat were tested on a clay soil at Rothamsted, Hertfordshire. Treatments comprised dressing seed with dusts containing 20% (standard) and 60% (high-rate) γ-BHC and 40% (standard) dieldrin, all at 2 oz. per bushel, 60% dieldrin at 70 oz. per bushel (high-rate), or a liquid containing 30% dieldrin at 1 fl. oz. per bushel; combine-drilling 0.5% γ-BHC dust at 1 cwt. per acre with the seed; and spraying the soil surface after sowing with 1 gal. 30% aldrin in 40 gal. water per acre. The high-rate BHC and dieldrin seed dressings, the combine-drilled BHC dust and the aldrin spray significantly reduced wireworm populations when applied to spring- or winter-sown wheat, the reduction in the former case being apparent two years later in one experiment; these reductions were, in general, reflected in increased yields. The standard seed dressings tended to be less effective. Similar results were obtained in an experiment on a fen peat soil in Lincolnshire.Tests done in one experiment on plots sown with dieldrin-dressed seed showed no evidence that birds grub up plants or seeds that would otherwise have germinated.
Observations on the Association of Ants with Coccids of Tea
Authors: Das G. M. 
Published: July 2009

Certain species of COCCIDAE that excrete honeydew and are attended by ants or enclosed in their nests are quite prevalent on tea bushes and seed trees in the plains of Assam and West Bengal but those which are not attended by ants are kept under considerable check by the activities of their natural enemies. In Darjeeling, where the natural enemies are fewer, a number of species occur abundantly and are often responsible for serious damage to tea.From the studies of the relative population of the ant, Crematogaster dohrni Mayr and the Coccid, Saissetia formicarii (Green), occurring on tea bushes it is doubtful if more than a small portion of the food requirement of the vast ant population in the nests which contain sexual forms could be met from the honeydew excreted by the small number of Coccids enclosed therein. The major part of food must, therefore, come from other sources. Insects attacking or visiting the tea bushes and tea seed trees or even those found on the ground appear to constitute the major part of the food of the ants, C. dohrni and Oecophylla smaragdina (F.).Several factors are responsible for the decrease in the population or disappearance of the Coccids in the absence of attendant ants. In the plains, Eriochiton theae Green, Coccus hesperidum L. and S. formicarii entirely disappear in the absence of attendant ants either due to the activities of their natural enemies or by contamination with honeydew accumulation or both. Parasitism may be slightly higher in ant-free colonies, but no estimation was possible since, in the absence of ants, the Coccids are quickly destroyed by predators.The ants do not protect the Coccids from Hymenopterous parasites; but their active movements hinder the parasites in their efforts to oviposit, and this leads to a reduction in the rate of parasitisation.In the presence of the ants, O. smaragdina and Crematogaster dohrni, predators are rare; they are destroyed as are any other insects or any foreign bodies that happen to be near their nests, whether they constitute food or not. The larvae of predators which have a protective covering or which resemble Coccids, if they happen to have gained access to the Coccid colonies, are not attacked by the ants, because they are not recognised as different from the Coceids.O. smaragdina does not normally transport Coccids, though young nymphs of E. theae and Coccus hesperidum may be aided in their dispersal, but Crematogaster dohrni and Crematogaster sp. are primarily responsible for the dispersal of S. formicarii and this takes place when an occasion arises to remove the Coccid to more favourable sites.O. smaragdina does not destroy the nymphs and sedentary form of Coccus hesperidum for food, but sedentary forms which are unable to establish themselves on transfer from withered leaves to a new nest are eaten.With the control of the attendant ants, the honeydew-producing Coccids disappear or at least they become rare. Conversely, where the Coccids are controlled, the ants automatically disappear.
Biology and Ecology of the Garden Chafer,Phyllopertha horticola(L.). vi.—The Flight Season: Reproductive State of Females
Authors: Milne A. 
Published: July 2009

SummaryThis part of the study of the garden chafer,Phyllopertha horticola(L) in the English Lake District deals with the reproductive state of the females during the flight season. Total egg-production depends entirely on stores (fat-body) accumulated in the final larval instar. On the average, the fat-body enables about 16 or 17 mature eggs to be manufactured per female, the usual range being 9–32. Rate of reproductive development is the same in the largest and smallest female adults. The outstanding mass features of the flight season are the two roughly equal and half-overlapping Phases: Phase 1, swarming over the grass sward, followed by Phase 2, swarming on the surrounding bracken, hedges and trees. Mass aspects of the female reproductive state throughout the two Phases are as follows.At primary emergence on the grass sward, females always contain some fat-body together with some fully developed and/or immature eggs. On the average they have about one-third of their full complement of eggs matured, the range being from none (with about 50% of the original fat-body still remaining) up to four-fifths (with about 10% of the fat-body). Since primary emergences in a homogeneous population extend over about a fortnight, females taken from the grass sward throughout Phase 1 are in various reproductive states. Thus after the first few days of the Phase and until the last individual makes its primary emergence, sample females may have half their fat-body and no eggs yet fully matured or no fat-body and all their eggs actually laid, or any intergrade between these extreme states. Towards the end of Phase 1 (which finishes about a week after the last primary emergence), females have no fat-body remaining and have already laid most or all of their eggs; and a small proportion of them now has food in the gut.In Phase 2, about 99 per cent, of females on bracken, hedges and trees contain no fat-body and therefore cannot manufacture any more eggs. On the average they have two mature or very nearly mature eggs left (range 0–26). This egg content is much the same as at death. The remaining 1 per cent, of females are aberrants with some fat-body still unconsumed. ‘ Bee-liners ’, the females which shoot out bullet-like from the bracken, hedges or trees to alight comparatively far afield, either have some fat-body remaining, or, if not, considerable numbers of eggs (mean about 9 as compared with the general mean of 2). Thus bee-liners are the phase-2 individuals with most eggs still unlaid. Obviously they are a minority.Deductions as to individual behaviour are made from the mass aspects of the reproductive state and are to be examined in the next paper of this series.Since females of the garden chafer have already laid all or most of their eggs before appearing on hedges and trees, gardeners will not control this pest by killing all they find on their hedges and trees.
Interaction of insecticide resistance genes in field populations of Culex pipiens (Diptera: Culicidae) from italy in response to changing insecticide selection pressure
Authors: Bonning B. C. , Hemingway J. , Romi R. , Majori G. 
Published: July 2009

AbstractCulex pipiens Linnaeus larvae were collected from various locations in Italy and colonized as separate strains. These were analysed for elevated nonspecific esterase activity and frequency of altered acetylcholinesterase (AChE) mechanisms of insecticide resistance, and bioassayed, to define the cross-resistance spectra conferred by these to organophosphorus and carbamate insecticides. These mechanisms were further characterized by polyacrylamide gel electrophoresis. Elevated esterase A1 (formerly known as Est 3A) which predominated in C. pipiens from Italy in 1985 had been replaced by two esterases, A2 and B2. Altered acetylcholinesterase was still present at high frequencies. Altered and normal acetylcholinesterase were distinguished by differential mobility on polyacrylamide gel electrophoresis. Levels of insecticide resistance were higher in the Lucca region of Italy than in other areas sampled, in response to intensive use of temephos and to a lesser extent chlor-pyrifos, employed to reduce mosquito biting nuisance to tourists in this area.