bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between bioassay data and the simulated field performance of insecticides against susceptible and resistant adult Bemisia tabaci (Homoptera: Aleyrodidae)
Authors: Cahill Matthew , Denholm Ian , Ross Gavin , Gorman Kevin , Johnston Diana 
Published: July 2009

AbstractAdults from seven strains of Bemisia tabaci (Gennadius) were tested with nine insecticides or combinations in both leaf-dip bioassays and the Rothamsted field simulators. A statistical model was used to describe the survival of the insects in the field simulators and comparisons made to the resistance factors from leaf-dip assays. Strains of B. tabaci shown to be susceptible in bioassays were well controlled by field rates of the insecticides in the field simulators. For each insecticide or combination, the degree of adult survival in field simulators after insecticide treatment was positively related to the resistance factor. However, similar resistance factors for different insecticides gave quite different adult field simulator survival. In populations with high resistance factors, adult mortality in the field simulators after insecticide application was not different to untreated controls. These data provide information about the implications of B. tabaci resistance on the field performance of insecticides.
Resolution of baseline responses and documentation of resistance to buprofezin in Bemisia tabaci (Homoptera: Aleyrodidae)
Authors: Cahill Matthew , Jarvis Wayne , Gorman Kevin , Denholm Ian 
Published: July 2009

AbstractThe insect growth regulator buprofezin was tested using a leaf-dip assay on immatures of Bemisia tabaci (Gennadius). The method was robust and repeatable, and baseline data were calculated for a laboratory strain and a number of field collections from Pakistan where the insecticide has not been used. A baseline LC50 of 0.53 ppm buprofezin was defined and compared to other field collections. Populations known or suspected to have been intensively selected with buprofezin showed substantial tolerance to the insecticide at both the LC50 and at specific diagnostic doses, with the highest resistance factor of 47 fold in a population from the Netherlands. Reasons for the variation between populations, biotypes and geographical areas are discussed and the dangers of human-assisted movement of resistance genes are highlighted.
Winter moth (Operophtera brumata(Lepidoptera: Geometridae)) outbreaks on Scottish heather moorlands: effects of host plant and parasitoids on larval survival and development
Authors: Kerslake J.E. , Kruuk L.E.B. , Hartley S.E. , Woodin S.J. 
Published: July 2009

AbstractOutbreaks of the winter moth,Operophtera brumataLinnaeus (Lepidoptera: Geometridae), have recently become widespread on heather moorlands in northeast Scotland. These outbreaks represent remarkable phenomena given the poor nutritional quality of the dominant moorland host plantCalluna vulgaris(Linnaeus) Hull (Ericaceae). Winter moth performance onC. vulgariswas compared with that on the other available moorland host plant,Vaccinium myrtillus(Linnaeus) (Ericaceae), and parasitism levels were measured in two moorland outbreak populations. Larval densities in the field were generally higher onCallunathan onVaccinium. However, larvae showed better survival, more rapid development and greater pupal weights onVacciniumthan onCalluna. Feeding trials indicated thatVacciniumwas more digestible thanCalluna. No evidence of parasitism was found in a high-altitude moorland winter moth outbreak population from mainland Scotland, but the parasitoidPhobocampe neglecta(Holmgren) (Hymenoptera: Ichneumonidae) was present in 27% of larvae from a lower-altitude moorland outbreak on Orkney. The results indicate that the presence ofVacciniumand the opportunity to escape from parasitism may facilitateO. brumataoutbreak formation in high-altitude moorland sites. However, neither factor can provide a full explanation for the present phenomenon.
Susceptibility of larvae of the sandflyPhlebotomus papatasi(Diptera: Psychodidae) toBacillus sphaericus
Authors: Pener H. , Wilamowski A. 
Published: July 2009

AbstractLaboratory experiments were conducted to measure the susceptibility of larvae of the sandflyPhlebotomus papatasiScopoli to the insect pathogenBacillus sphaericusapplied to the larval breeding medium.B. sphaericushad no effect on larvae aged 30 ± 2 days old, but larvae aged 13 ± 2 and 20 ± 2 days were highly susceptible and a clear dose response effect was detected. WhenB. sphaericuswas left in the rearing medium for 18 days there was a significant increase in larval mortality, indicating persistence and possibly recycling. The results support the feasibility of employingB. sphaericusin the integrated control of sandflies.
Population status of the bush fly, Musca vetustissima (Diptera: Muscidae), and native dung beetles (Coleoptera: Scarabaeinae) in south-eastern Australia in relation to establishment of exotic dung beetles
Authors: Tyndale-Biscoe Marina , Vogt W.G. 
Published: July 2009

AbstractWe compare the pest status and age structure of bush fly,Musca vetustissima Walker, populations, and the abundance of native dung beetles at Uriarra, ACT, for five fly seasons before (1976–81) and three seasons after (1990–93) the exotic dung beetles Euoniticellus fulvus (Goeze) and Onthophagus taurus (Schreber) became established in the area during the late 1980s. Fly populations in all post-introduction seasons of 1990–93 were much older than in the pre-introduction seasons, indicating reduced levels of local fly breeding and higher proportions of immigrants. During the pre-introduction period, the fly annoyance index exceeded the ‘minimum discomfort’ threshold of 10.0 in parts of all seasons. The mean index was 11.3, and this did not differ significantly between seasons. The total dry weight of dung beetles at the time of the first influx of bush flies each year was consistently below 3 g/dung pad which was apparently too low to depress bush fly breeding below their replacement level of 3%. The mean annoyance index of 3.1 for the 1990–91 season was significantly lower than for the pre-introduction period and the total dry weight of beetles during November-December exceeded 3 g/dung pad on all sampling occasions. In the 1991–92 and 1992–93 seasons fly annoyance indices reverted to pre-introduction levels (seasonal means of 13.7 and 7.8 respectively) and total dry weight of beetles was again below 3 g/dung pad when the bush flies first appeared. Survival of immature bush flies in local dung pads remained below the replacement level of 3% during 1990–91, but exceeded 3% on two occasions during 1991–92. Apart from 1976–77, when mean catches of native dung beetles (O. australis and O. granulatus) were exceptionally high, mean catches of native dung beetles during pre- and post-introduction years were very similar, but the mean dung beetle biomass increased following the establishment of exotic species.
Effect of pirimicarb on the foraging behaviour of Diaeretiella rapae (Hymenoptera: Braconidae) on host-free and infested oilseed rape plants
Authors: Umoru P.A. , Powell W. , Clark S.J. 
Published: July 2009

AbstractThe effects of the aphicide pirimicarb on the foraging behaviour of the aphid parasitoid Diaeretiella rapae were investigated in the laboratory, using aphid-infested and uninfested, young oilseed rape plants. Female parasitoids spent significantly less time foraging on plants sprayed with pirimicarb within the previous 24 h than on untreated plants, regardless of the presence of aphid hosts. Whilst foraging on sprayed plants, parasitoids spent relatively more time walking than they did when foraging on untreated plants. On sprayed plants foraging parasitoids tended to avoid leaf surfaces, thereby reducing the chances of encountering aphid hosts whilst on the plant. These sublethal effects of the aphicide on foraging parasitoids would considerably reduce their impact on aphid populations which survived in a crop after spraying. This has important implications for the control of aphids, such as Myzus persicae, which have developed pesticide resistant strains.
Multitrophic interactions and management of the diamondback moth: a review
Authors: Verkerk Robert H.J. , Wright Denis J. 
Published: July 2009

AbstractThe diamondback moth,Plutella xylostellaLinnaeus (Yponomeutidae), remains one of the most serious pests of crucifers in many parts of the world, particularly in South East Asia. This paper reviews the wide array of strategies which have been used in attempts to controlP. xylostellaover the last 40 years and consolidates the fragmented and sometimes hard-to-access literature on two and three level trophic interactions (e.g. host plant—herbivore, herbivore—natural enemy and host plant-herbivore—natural enemy interactions) involving the pest. Special reference is made to studies and examples from South East Asia, and in particular Malaysia, whereP. xylostellaand its primary parasitoids have been well studied owing to the great economic significance of the pest in this region. It is suggested that a multitrophic approach to research may assist in the development of more sustainable methods for the management ofP. xylostellaand overcome some of the problems inherent with insecticide-intensive methods.
Age composition of the filarial vector Culex quinquefasciatus (Diptera: Culicidae) in Calcutta, India
Authors: Chandra G. , Seal B. , Hati A.K. 
Published: July 2009

AbstractAge composition of the filarial vector mosquito Culex quinquefasciatus (Say) was determined by examining the number of ovariolar dilatations of 1200 adult females from Calcutta. Average duration of the gonotrophic cycle was 4.5 days. The proportion parous, the daily survival rate and daily mortality rates of the natural population were 0.53, 0.87 and 13%, respectively. The oldest mosquito sampled in the study area passed eight gonotrophic cycles in its lifetime.
Ecological and geographical variations in the siphonal index of Culex pipiens larvae (Diptera: Culicidae)
Authors: Vinogradova E.B. , Reznik S.Ya. , Kuprijanova E.S. 
Published: July 2009

AbstractCulex pipiens Linnaeus is represented by two forms: the form molestus which is autogenous, stenagamous and has no reproductive diapause, and the form pipiens which is anautogenous, eurygamous and diapauses. The ecological, physiological and geographical variations in the larval siphonal index of C. pipiens (the ratio of the length of the siphon to its width at the base) was investigated using both original measurements and previously published data. In all, data were used from 259 collections from open water bodies (marshes, ditches, holes, barrels, etc.) and underground waters (house basements) in areas of Europe, Asia and part of Africa. Autogeny was studied in some cases by dissection of females. In C. pipiens the mean siphonal index was strongly correlated with ecology (water body type) and adult physiology (autogeny). In spite of high geographical and individual variation, which makes the identification of individual larvae difficult, the mean siphonal index can be used with certainty for the differentiation of populations of the two forms of C. pipiens.
‘Phytophagous’ thrips are facultative predators of twospotted spider mites (Acari: Tetranychidae) on cotton in Australia
Authors: Wilson L. J. , Bauer L. R. , Walter G.H. 
Published: July 2009

AbstractPredatory feeding on Tetranychus urticae Koch (Acari: Tetranychidae) populations on cotton by phytophagous thrips, Thrips imaginis Bagnall, T. tabaci Lindeman and Frankliniella schultzei Trybom (Thysanoptera: Thripidae), was investigated in the field and laboratory. Phytophagous thrips are a common early season pest of cotton in Australia, though their true pest status is undefined. In California, the phytophagous thrips (Frankliniella occidentalis (Pergande)) is regarded as an opportunistic predator of mite eggs, their consumption of which increases fitness over a diet of leaf tissue alone. Thrips are among the most abundant of insects on young cotton. If they consume mite eggs, even at relatively low rates, they could have a significant influence on the probability of survival of early season spider mites. Consumption of eggs of T. urticae by thrips was investigated in the laboratory. Second instar F. schultzei consumed more eggs per day (ca. 4 eggs per day) than did second instar T. tabaci or T. imaginis (ca. l egg per day). Consumption by first instar F. schultzei was much lower than for second instars. Adult T. tabaci consumed ca. l egg per day whilst adults of F. schultzei consumed only ca. 0.5 eggs per day, although some individuals of this species did consume substantial numbers of eggs. Larvae of all thrips species showed a type II functional response to prey density. In the field, adults and larvae of T. tabaci and F. schultzei showed a preference for cotton seedlings that were also infested by spider mites. In a glasshouse, larvae of T. tabaci showed a highly significant preference for feeding within mite colonies. In the field, suppression of predators, predominantly T. tabaci and F. schultzei, with a broad spectrum insecticide (dimethoate) contributed to outbreaks of mites occurring earlier than they would have otherwise. The results show that phytophagous thrips eat mite eggs and that they are potentially important predators of spider mites in the field, especially given their abundance on young cotton and preference for inhabiting situations in which mite colonies are found.
The ovarian cycle in Culicoides barbosai Wirth & Blanton and C. furens (Poey) (Diptera, Ceratopogonidae)
Authors: Linley J. R. 
Published: July 2009

The ovarian cycle in Culicoides barbosai Wirth & Blanton and C. furens (Poey), two biting midges of considerable importance in Jamaica, was studied in the laboratory. In C. furens, a single blood-meal was sufficient for development of a substantial number of eggs; in C. barbosai, which took a relatively smaller blood-meal, very few eggs were matured (usually between 10 and 20 but sometimes fewer than 10), and some females failed to produce any eggs at all.A high degree of gonotrophic harmony was observed in C. furens, but in C. barbosai the degree of harmony was low and a large proportion of the ovarian follicles degenerated; these differences may be associated with the relative size of the blood-meals of the two species.The duration of the gonotrophic cycle (from feeding to the appearance of mature eggs in the ovaries) at 68, 77, 85 and 91°F. was 156, 104, 82 and 72 hr., respectively, in C. barbosai and 102, 59, 42 and 36 hr. in C. furens.In experiments on the effect of temperature and carbohydrate feeding on egg production, temperature did not influence egg production in C. barbosai, and greater numbers of eggs were not matured by females given access to honey during the period of egg development. However, access to honey did increse the proportion of individuals surviving the period of egg maturation and also the numbers that mastured any eggs at all. Females of C. furens kept at 77°F. matured more eggs than those kept at 91 or 85°F.; access to honey improved survival, but its effects on egg production were inconclusive in these experiments.Observations indicated that adults of both species are probably in the habit of taking carbohydrate food in nature.Females of both species may be autogenous, though the proportion of such individuals varied considerably between populations from different breeding sites. Autogenous females of both species emerged from the pupa with ovaries already relatively well developed; in C. barbosai the ovarian follicles were in Stage IIB or III, in C. furens they were in late Stage IIA or IIB. Large numbers of eggs were matured by autogenous females of the former, and the same is probably true of the latter.The egg stage is apparently of longer duration C. barbosai than in C. furens. At 68, 77, 85 and 91°F., most eggs of C. barbosai hatched on days 12, 6–7, 5–6 and 5, respectively, whereas at the three higher temperatures most eggs of C. furens hatched on days 4, 3 and 2. Percentage fertility varied between individual egg batches of both species.
Measurements by two methods of the susceptibility to DDT and Dieldrin of Glossina palpalis (R.-D.) in Northern Nigeria
Authors: Riordan K. 
Published: July 2009

The susceptibilities to DDT and to dieldrin of one-day-old teneral examples of Glossina palpalis (R. -D.), obtained from pupae collected from the field, were measured in the laboratory in Nigeria by two methods, one recommended by the W.H.O. Expert Committee on Insecticides (1963) and the other described by Kernaghan & Johnston (1962).Pupae were kept in dry sand at a controlled temperature of 78–79°F. and 70–80 per cent. relative humidity until the adult flies emerged, and the latter were then kept individually in 3 × 1 in. glass tubes. All exposures to insecticides were carries out at room temperatures. Five flies were exposed together for one hour in the W.H.O. method, and flies were exposed individually for 1 1/2 minutes in the other method. After exposure, they were kept in a cabinet at 78–79°F. and 60–70 per cent. relative humidity. Mortalities were assessed 8, 24 and 48 hr. after the end of exposure, but only the 24-hr. results are presented. Regression lines and values for LC50’s were calculated by the method of probitsThe mortalities amongst untreated flies averaged 5.6 per cent. for males and 5.1 for females, the latter value being insignifiantly affected by the method used. Dieldrin was far more toxic than DDT to both sexes, and females were apparently more susceptible than males to both insecticides; it is suggested that females pick up relatively more of a given deposit because of their greater weight.The slope of the regression line relating mortality to insecticide concentration was steeper for long exposures than for short ones; it is suggested that this comes about because some insecticide picked up by the flies is lost after they are removed from the treated surface, the loss being relatively greater when greater discussed, and it is concluded that exposure for 1 1/2 minutes is long for satisfactory assessment of susceptibility when continuous contact with the insecticide is ensured (as in the method used for this period), but that exposure for 1 hour, ensuring 100 per cent. mortality at some concentrations, is preferable for detection of resistance. Although mortality from an insecticide may not be completed until 72 hr. after exposure, observations 24 hr. after are considered adequate.The relative merits of the two methods of testing susceptibility are discussed. It is concluded than the method of Kernaghan & Johnston, which involves less handling and therefore less stimulation of the flies, is the more precise. The impregnated papers available from W.H.O. are a convenient means of exposing flies to known deposits of insecticide.
Investigations of the chemical control of insect pests of cotton in central Africa. II.—Tests of insecticides with larvae and adults
Authors: Matthews G. A. 
Published: July 2009

Further tests of insecticides, mainly carbaryl, endosulfan, endrin and DDT, for possible use against pests of cotton in Central Africa are described. In laboratory tests in Rhodesia, carbaryl was the most effective against first-instar larvae of Diparopsis castanea Hmps. exposed on leaves, stems and bracts of effective against second-instar larvae of Heliothis armigera (Hb.), to which the insecticides were applied directly, and carbaryl the least.When adults of Dysdercus intermedius Dist. and D. fasciatus Sign. were caged with treated bolls, carbaryl was the most effective, endrin the next and (against the former sp. only) endosulfan the least. Deposits on leaves from 0.5 per cent. sprays of carbaryl, DDT and endosulfan remained effective in dry conditions for two weeks, but application of 0.05–1.0 in of simulated rain reduced their effectiveness immediately, especially that of carbaryl. The effectiveness of deposits was also reduced by plant growth and was affected by plant habit; on a hairy variety the deposits persisted longer than on a glabrous one, partly because the hairs retained them and partly because they made movement of the larvae more difficult.
Bioassay and histochemical studies of the poisoning and recovery of house-flies (Musca domestica L.) treated with diazinon and diazoxon
Authors: Farnham A. W. , Gregory G. E. , Sawicki R. M. 
Published: July 2009

Newly emerged and 3-day-old house-flies (Musca domestica L.) of a diazinin-susceptible and a diazinon-resistant strain were treated topically with diazinon or diazoxon and examined for symptoms of poisoning and recovery at intervals up to 5 hours and at 24 hours after treatment. The effects of the poisons varied with the age and strain of the flies and with the poison used. Most of the flies that became paralysed died, but some recovered, even after appearing to be dead. Of flies treated when newly emerged, more of the resistant than of the susceptible strain recovered from paralysis, and more recovered from diazoxon than from diazinon treatment. Recoveries were fewer amongst flies treated when three days old and occurred in appreciable numbers only amongst those of the resistant strain treated with diazoxon.Histochemical tests on flies, treated with diazoxon showed a close correlation between inhibition of cholinesterase activity in the thoracic ganglion and the external symptoms of poisoning. Inhibition was slight in apparently unaffected flies, more extensive in severely affected flies, and total or nearly so in completely paralysed flies. Inhibition first appeared at the periphery of the ganglion and spread inwards to the centre. Flies that recovered from paralysis had normal or almost normal cholinesterase activity, partially recovered flies showed activity only in the central parts of the ganglion. Recovery of cholinesterase activity seems to occur from the centre of the ganglion outwards.