bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantifying the impact of insect predators and parasitoids on populations of the apple ermine moth,Yponomeuta malinellus(Lepidoptera: Yponomeutidae), in Europe
Authors: Kuhlmann U. , Carl K.P. , Mills N.J. 
Published: July 2009

AbstractLife tables were developed to assess the significance of natural enemies on the dynamics of apple ermine moth,Yponomeuta malinellusZeller, in southwestern Germany and to select parasitoid species for use in the biological control of this pest in Canada. During the study from 1993 to 1995 the abundance ofY. malinellusvaried from 1.5 to 4.3 tents per 100 leaf clusters indicating that this was a non-outbreak population. From the life tables it was evident that the impact of egg predators accounted for 25–43% of the total generational mortality ofY. malinellus, more than any other known mortality factor. Percent parasitism varied from 18 to 30%, but the impact of parasitoids in relation to the total generational mortality ofY. malinellusfrom the life tables was remarkably constant at 11–14%. The loss of potential fecundity had an important influence on the generational mortality ofY. malinellus, but declined from 27% to 15% over the course of this study. This decline corresponded with a rise in the net rate of increase R0from 1.35 in 1993 to 6.8 in 1995, despite the impact of insect predators and parasitoids on the generational mortality.Yponomeuta malinelluswas attacked by five different obligate primary parasitoids, a single obligate hyperparasitoid, and three facultative hyperparasitoids. Of these, the oligophagous egg-larval parasitoidAgeniaspis fuscicollisDalman (Encyrtidae) and the oligophagous larval-pupal and pupal parasitoidHerpestomus brunnicornisGravenhorst (Ichneumonidae) were selected as potential biological control agents for Canada due to a minimal degree of interspecific competition.
Malathion-specific resistance in a strain of the rust red grain beetle Cryptolestes ferrugineus (Coleoptera: Cucujidae)
Authors: Spencer A.G. , Price N.R. , Callaghan A. 
Published: July 2009

AbstractA strain of Cryptolestes ferrugineus (Stephens) bred for malathion-specific resistance was found to be 650 fold resistant at LD50 when compared with a susceptible strain bred from the same stock. Resistance was more than 98% synergized by triphenyl phosphate and S,S,S-tributyl phosphorotrithioate, but unaffected by piperonyl butoxide. AChE inhibition by malaoxon varied slightly between the strains. Non-specific esterase activity as measured by the hydrolysis of α-naphthyl acetate was slightly reduced in the resistant strain whereas there were no inter-strain differences in the hydrolysis of β-naphthyl acetate. Products of in vitro metabolism of malathion were identified by thin-layer chromatography and gas chromatography-mass spectrometry as α- and β-malathion mono-acids. It was therefore concluded that resistance was due to the hydrolytic breakdown of malathion by a malathion-specific carboxylesterase. The rate of in vitro malathion hydrolysis was found to be 31 times greater in the resistant strain. In vitro inhibition studies indicated that resistance is attributable to a carboxylesterase unique to the resistant strain. The implications of these results are discussed in relation to work recently carried out on malathion-specific resistance in dipterous species.
Spectral sensitivity and visual conditioning in the parasitoid wasp Trybliographa rapae (Hymenoptera: Cynipidae)
Authors: Brown P.E. , Frank C.P. , Groves H.L. , Anderson M. 
Published: July 2009

AbstractSpectral sensitivity of the wasp Trybliographa rapae (Westwood), a parasitoid of cabbage root fly larvae, was measured by the electroretinogram (ERG) technique and by a complimentary behavioural technique, to 15 selected wavelength bands from 340 to 670 nm. Peaks of electroretinogram sensitivity were found in the ultraviolet, blue and green-yellow regions of the spectrum. This corresponds to known classes of photoreceptor present in the Hymenoptera. Behavioural peaks of phototactic attraction were found in the ultraviolet and green-yellow regions, but not in the blue. No differences were observed between the sexes. We suggest that ultraviolet and green-yellow wavelengths initiated ‘escape’ and ‘foliage’ orientated behaviour respectively. Blue wavelengths appear to have a less specific function but may be important for colour discrimination. Blue wavelengths did, however, become significantly more attractive to female wasps after a pre-experimental conditioning period involving exposure to blue wavelengths in combination with swede infested with cabbage root fly larvae. Thus T. rapae has been demonstrated to show plasticity in its visually motivated behaviour. This may prove advantageous in the development of an artificial egg collecting technique for this species.
The influence of host quality on progeny and sex allocation in the pupal ectoparasitoid,Muscidifurax raptorellus(Hymenoptera: Pteromalidae)
Authors: Harvey J.A. , Gols G.J.Z. 
Published: July 2009

AbstractMuscidifurax raptorellusKogan & Legner is a gregarious pteromalid ectoparasitoid that attacks pupae and pharate adults from several families of the higher Diptera. Egg-to-adult development time, adult parasitoid size and emerging offspring ( = secondary) sex ratio ofM. raptorelluswere compared with clutch size in two hosts that differed greatly in mass, the smallMusca domesticaLinnaeus and the largerCalliphora vomitoriaLinnaeus. The mean number of emerging parasitoids did not vary significantly with host species, although slightly higher clutch sizes were recorded inC. vomitoria. Irrespective of offspring sex, parasitoids completed development more rapidly inM. domesticathan inC. vomitoria. In the small host, the development time and adult size ofM. raptorelluswere negatively correlated with clutch size. By contrast, female parasitoid size was unaffected by clutch size in the larger host,C. vomitoria. In both hosts, female parasitoids were significantly larger than male parasitoids. The secondary sex ratio (percentage males) of emerging parasitoids was significantly lower inC. vomitoria, and varied with clutch size in both hosts. InC. vomitoria, the greatest proportion of females emerged from hosts with the highest clutch sizes, whereas inM. domesticahosts with the highest clutch sizes produced the lowest proportion of female progeny. The results described here show that the development ofM. raptorellusis profoundly affected by interspecific differences in host quality. Our results suggest that mating structure and host quality have potentially different effects on sex ratio decisions inM. raptorellus, and perhaps other gregarious parasitoids.
Laboratory evaluation of flight ability of the Oriental corn borer, Ostrinia furnacalis (Lepidoptera: Pyralidae)
Authors: Shirai Y. 
Published: July 2009

AbstractFlight ability of Ostrinia furnacalis Guenée was evaluated using a flight-mill in laboratory. Females flew most actively at 20–23°C, whereas the majority of the moths tested did not fly at 14–17°C. Temperature above 26°C inhibited their flight activity and survival. The age-specific flight ability of unmated males and females was similar from one to 12 days after emergence; it was highest at one day and then declined gradually. Females showed a pre-oviposition period of three to four days after emergence during which they were capable of longer continuous flight. There was no significant difference between the unmated and mated females in any aspect of flight ability at four days (commencement of oviposition) or at eight days old (peak of oviposition). In males, the flight ability of mated adults was reduced compared with that of unmated adults at both four and eight days old. Increased flight experience did not delay oviposition by mated females, but significantly reduced egg production. There was a significant negative correlation between flight duration and subsequent egg production. Ostrinia furnacalis is concluded to be an active flier that is able to male long-distance flights, because both mated and unmated adults displayed high flight ability for several days after emergence.
Bacillus thuringiensisisolates from the Philippines: habitat distribution, δ-endotoxin diversity, and toxicity to rice stem borers (Lepidoptera: Pyralidae)
Authors: Theunis W. , Aguda R.M. , Cruz W.T. , Decock C. , Peferoen M. , Lambert B. , Bottrell D.G. , Gould F.L. , Litsinger J.A. , Cohen M.B. 
Published: July 2009

AbstractBacillus thuringiensisBerliner isolates were detected in 57% of 801 samples of rice grain dust, soil, rice field arthropods, and miscellaneous habitats (rice straw compost and mammal faeces) collected at 100 sites in the Philippines. The collection yielded 3950 isolates ofB. thuringiensis(8.7 isolates/positive sample). Grain dust from rice mills was the richest source (63% of the samples were positive, with 10.2 isolates/positive sample), followed by rice field arthropods, soil, and miscellaneous habitats. Polyclonal antibodies to six δ-endotoxin groups (Cry1A, Cry1B, Cry1C, Cry1D, Cry1E, and Cry3A) were used in enzyme-linked immunosorbent assays (ELISA) to characterize the toxins produced by each isolate. Subsamples of isolates representing the diversity of isolate sources and δ-endotoxin profiles were bioassayed against the yellow stem borer,Scirpophaga incertulas(Walker) and striped stem borer,Chilo suppressalis(Walker). Eighteen isolates highly toxic to both species were selected for characterization of δ-endotoxin genes by polymerase chain reaction (PCR) with primers specific to 14 genes or gene subfamilies, and Western blotting with Cry2A antibodies. At least two novel δ-endotoxin genes, related tocry1Bandcry1F, were detected by DNA sequencing of PCR products.
Life history and feeding biology of the predatory thrips, Aleurodothrips fasciapennis (Thysanoptera: Phlaeothripidae)
Authors: Watson D.M. , Du T.Y. , Li M. , Xiong J.J. , Liu D.G. , Huang M.D. , Rae D.J. , Beattie G.A.C. 
Published: July 2009

AbstractDetails of the life history, the effects of relative humidity and temperature on survival and reproduction, and the predatory ability of Aleurodothrips fasciapennis Franklin were examined under laboratory conditions. Stage-specific development and adult longevity were similar between sexes, and the adult sex ratio was 1:1. Females laid 23.3 ± 18.0 eggs of which 83% hatched. The survival rate of first instars to adulthood was 82%. The intrinsic rate of natural increase (rm) was 0.04, assuming a zero or 5.4 day pre-oviposition interval. Temperature did not affect the proportion of eggs that hatched, the proportion of first instars surviving to adulthood or adult sex ratios. However, female fecundity was dependent on temperature being highest at 24 ndash 28°C. Relative humidity did not affect adult sex ratio or female fecundity but the proportion of eggs hatched and the survival of first instars to adulthood increased as relative humidity increased. Few eggs hatched when relative humidity was <65%. Larval and adult female A. fasciapennis were voracious feeders but the number of prey killed per progeny was high, suggesting A. fasciapennis was inefficient at converting prey into progeny biomass. The potential value of A. fasciapennis as a biocontrol agent of Aonidiella aurantii (Maskell) on Australian citrus is discussed in terms of its rm, prey killing power and environmental adaptability. It is concluded that population growth of A. fasciapennis should exceed that of A. aurantii under field conditions but A. fasciapennis may be of little value against A. aurantii on citrus grown under conditions of high temperature and low humidity, or when prey densities are low.
Relationship to human biting collections and influence of light and bednet in CDC light-trap catches of West African malaria vectors
Authors: Costantini C. , Sagnon N.F. , Sanogo E. , Merzagora L. , Coluzzi M. 
Published: July 2009

AbstractThe efficiency of miniature CDC light-traps in catching West African malaria vectors was evaluated during two rainy seasons in a village near Ouagadougou, Burkina Faso. Traps were employed both indoors and outdoors using human baits protected by an insecticide-free mosquito-net and different sources of light. Indoors, light from incandescent bulbs increased the catch of Anopheles gambiae s.l. (mainly A. arabiensis Patton and the Mopti chromosomal form of A. gambiae s.s. Giles) and A. funestus Giles c. 2.5 times as compared to traps whose light bulb was removed. Conversely, the difference was not significant when a UV ‘Blacklight-blue’ fluorescent tube was compared to the incandescent bulb. Protecting the bait with a mosquito-net increased the catch c. 3 times for A. gambiae s.l. and c. 3.5 times for A. funestus. A prototype model of double bednet gave intermediate yields. Outdoors, the addition of incandescent bulbs to unlighted traps did not significantly increase the number of vectors caught, but the addition of the mosquito-net to the unprotected human bait did so by c. 1.5–4 times. Thus, the CDC light-trap hung close to a human sleeping under a bednet and fitted with an incandescent bulb, was considered the most practical and efficient in terms of numbers of vectors caught, consequently its indoor efficiency was compared to human landing catches on single collectors and estimated to be 1.08 times and density-independent. Outdoor light-trap catches were either not significantly correlated to biting collections (as for A. gambiae s.l.), or density-dependent in their efficiency (as for A. funestus); thus, they were not considered a reliable means for estimating malaria vector outdoor biting densities in this area. No difference was found in the parous rate of A. gambiae s.l. samples obtained with CDC light-traps and human landing collections.
Genetic diversity of an introduced pest, the green spruce aphidElatobium abietinum(Hemiptera: Aphididae) in New Zealand and the United Kingdom
Authors: Nicol D. , Armstrong K.F. , Wratten S.D. , Walsh P.J. , Straw N.A. , Cameron C.M. , Lahmann C. , Frampton C.M. 
Published: July 2009

AbstractThe green spruce aphidElatobium abietinum(Walker) is an introduced pest in the United Kingdom and more recently in New Zealand. In outbreak years this aphid can cause severe defoliation and sometimes death of spruce trees (Piceaspp.). As chemical control is not financially viable, other options including host-plant resistance and biological control are currently being investigated. An understanding of the genetic variation of this pest is imperative in fully utilizing these control strategies. To examine this,E. abietinumwas collected from Sitka sprucePicea sitchensisfrom four locations in the UK that were up to 240 km apart. Of these, 40 aphids were analysed via two alternative polymerase chain reaction (PCR) analyses using primer pairs. The first analysis used 10-mer random primers, whilst the second analysis used primers designed to amplify across the intergenic spacer region of rDNA. Combining results from the two analyses allowed the 40 UK aphids to be separated into 28 different genotypes. The genetic variation was also high within each UK site, with 77 to 89% of the aphids sampled being of a different genotype. The two PCR analyses were subsequently used to examine 40 aphids across six sites in New Zealand up to 1200 km apart. No genetic variation was identified. Further analysis of several of these New Zealand aphids with 87 individual 10-mer primers and two polymerase enzymes, still did not detect any genetic variation. The high degree of genotypic diversity in the UK populations was presumably due to a longer period of establishment, multiple introductions and/or sexual reproduction. The contrasting lack of genetic variation in New Zealand populations was probably due to a very limited founder population, continued isolation and lack of sexual reproduction. Reduced genetic diversity can seriously decrease the ability of a population to adapt to control strategies. Therefore the durability of certain control methods may be more readily maintained in such an isolated population in New Zealand.
Flight initiation and flight activity in Prostephanus truncatus (Coleoptera: Bostrichidae)
Authors: Scholz D. , Borgemeister C. , Markham R. H. , Poehling H. M. 
Published: July 2009

AbstractIn an outdoor experimental set-up, the number of Prostephanus truncatus (Horn) flying from maize cobs was recorded over 38 observation weeks. Flight activity in the field was recorded for 50 weeks with three pheromone traps, each placed at c. 100–300 m from the first experimental set-up. Multiple regression analyses revealed that both flight initiation and flight activity were partly influenced by mean temperatures, but were not directly related. Flight initiation was mainly dependent on population density. An additional experiment showed that sex ratios among pheromone trap catches were not correlated with the number of beetles caught; sex ratios were female-biased throughout the year. Seasonal fluctuations in flight activity recorded with pheromone traps are mainly dependent on changes in the number and sizes of beetle populations in a given area, as well as on breeding site availability and suitability.
The Selection of a Standard Insect for the Laboratory Testing of Insecticides
Authors: Craufurd-Benson H. J. 
Published: July 2009

1. The standards adopted by the author for a test insect suitable for the laboratory testing of insecticides are given.2. The inadvisability of using insects collected in the field, or insects that do not breed naturally throughout the year, is illustrated.3. The results of a search amongst stored-product insects, involving the testing of 27 different species, are given.4. Ahasverus advena, Oryzaephilus surinamensis and Oryzaephilus mercator have been found to be suitable laboratory test insects.
Plutella maculipennis, Curt., its natural and biological Control in England
Authors: Hardy J. Eliot 
Published: July 2009

1.Plutella maculipennis, Curt., a widespread Lepidopterous pest ofBrassicawas introduced into New Zealand about sixty years ago. In most countries a high degree of natural control is maintained, but in New Zealand the moth population is permanently maintained at a high level. Investigation showed that in New Zealand there were no natural enemies of importance, while in other areas these are constantly associated withPlutella.2. The distribution of the moth throughout the world is exceedingly wide, but in England it only occasionally reaches pest proportions.3. Preliminary work indicated that two Campoplegines,Angitia cerophagaandA. fenestralis, constantly parasitized large numbers of thePlutellalarvae. Initial efforts were devoted to collecting and breeding a large supply of these in England for introduction into New Zealand as controlling agents.4. From several thousand specimens ofPlutella, fourteen species of parasites were recovered, of which eight were hyperparasites. The only parasites which were numerically important were the two parasites,Angitia cerophagaandA. fenestralis. Their efficiency is not impaired to any appreciable extent by hyperparasites. A key showing the diagnostic differences of the parasites and hyperparasites ofPlutellais given.5. These two species ofAngitiaare commonly recorded as parasites ofPlutellathroughout the world, although under different names. A large quantity was bred in the laboratory and despatched to New Zealand after overcoming certain difficulties connected with transport. It appears that both species of parasite must overwinter in other hosts thanPlutella.6. Certain experiments were performed in an endeavour to assess some of the effects of climate. The upper limiting temperature ofPlutellais approximately 40°C. and the lower limit for breeding purposes about 10°C. All stages of the moth can survive short periods of cold greater than 10°C., but it is believed that hibernation is normally accomplished in the adult stage. As the immature stages of the moth live in a specialised microclimate of high humidity, changes in the moisture content of the general atmosphere have little effect. Rain, if appearing at certain critical times in the life-cycle, may be a controlling agent.7. The most favourable areas for multiplication of the moth appear to be in the sub-tropics and warmer temperate zones. It is suggested thatPlutellaoriginated in the Mediteranean region.8. Even in the cooler temperate countries the climate would allow an indefinite increase in the moth. It is believed that an effective check on this multiplication is supplied by parasites.9. As the climate of England and New Zealand are essentially similar there is reason to suppose that the introduction of parasites from the former country will lead to eventual control being obtained in New Zealand.
The Summer Hosts of Aphis fabae, Scop.
Authors: Jones Margaret G. 
Published: July 2009

1. When spring migrants of Aphis fabae, Scop., from Euonymus europaeus and Viburnum opulus are given a choice of summer host plants enclosed by a muslin cage, they colonise bean first and then sugar beet. Dock, poppy and Chenopodium are colonised in no very definite order, but thistle is the last plant to be infested.2. Further infestation of surrounding plants takes place rapidly by means of apterae, which migrate actively and colonise plants at random.3. The total number of Aphids on the summer host plants is of the same order as the times of colonisation.4. The effect of parasites and predators is proportional to the numbers present and to the size of the colony.5. The results do not indicate the presence of biological races on the chosen host plants.I should like to thank Mr. F. G. W. Jones, of the School of Agriculture, Cambridge, for his help in preparing the ground for the plots and in rearing some of the plants, and Dr. W. H. Thorpe for his criticism.
Notes on Culicine Mosquitos in Tanganyika Territory
Authors: Harris W. Victor 
Published: July 2009

The examination of mosquito larvae collected by house searchers on Stegomyia control measures in Dar-es-Salaam, the largest town in Tanganyika, shows that Aëdes aegypti is definitely the predominant domestic breeder there. The other species of the genus Aëdes encountered are listed with their frequencies.Similarly the examination of larvae found in tree-holes in Dar-es-Salaam shows that Aëdes aegypti, A. simpsoni and A. metallicus are regularly encountered.A system of obtaining an index of the population density of both A. aegypti and A. simpsoni, unconnected with the actual process of Stegomyia control measures, is described. This would be applicable to smaller towns, rural districts, and towns in high rainfall areas where A. aegypti is not the only danger as a yellow fever vector, and where extra-domestic breeding is important. The system is based on the exposure of a fixed number of bamboo pots containing water for a constant period of days, to attract egg-laying female mosquitos. Species of mosquitos and their frequencies obtained in a series of trials are given.