bluuebunny/crossref_metadata_2025 huggingface dataset:
Intensification of insecticide resistance in UK field populations of the peach-potato aphid, Myzus persicae (Hemiptera: Aphididae) in 1996
Authors: Foster S.P. , Denholm I. , Harling Z.K. , Moores G.D. , Devonshire A.L.
Published: July 2009

The well-established carboxylesterase-based resistance to insecticides in Myzus persicae Sulzer has recently been accentuated by the appearance of aphids with a modified acetylcholinesterase (MACE) insensitive to pirimicarb and the novel aphicide, triazamate. This target site resistance mechanism was found in M. persicae from crops in the UK for the first time in 1996, together with especially large proportions of aphids with R2 and R3 levels of carboxylesterases, a combination that was associated with serious insecticide failures. This paper describes the incidence of both mechanisms and discusses the implications for future recommendations for aphid control in the UK.
Evaluation of Shin-Etsu twist-tie rope dispensers by the mating table technique for disrupting mating of the cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae), and the pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae)
Authors: Kehat M , Anshelevich L , Gordon D , Harel M , Dunkelblum E
Published: July 2009

Different Shin-Etsu twist-tie rope formulations, containing either the cotton bollworm, Helicoverpa armigera (Hübner) pheromone or pink bollworm, Pectinophora gossypiella (Saunders) pheromone, or both, in the same rope, were tested in Israel for mating disruption. The success of mating disruption was evaluated by the mating table technique, comparing the percentage of mating of virgin sentinel females in pheromone-treated and control plots. Two variants of this technique were evaluated, one with two mating tables per plot, each containing five to seven females, and the other with six to eight mating tables per plot, with only one female per table. The latter method was more sensitive than the former, particularly at low population densities. Two tests were conducted in 1995 in order to compare a blend of five components of H. armigera pheromone with a blend of two components for mating disruption. The application consisted of 2000 ropes/ha, each with 80 mg pheromone. Evaluation by the two mating table methods showed clearly that the formulation containing two components was superior to the five-component blend for mating disruption, suppressing mating almost completely for 49 days. A new combined formulation, HPROPE, containing 175 mg of the H. armigera two component blend and 65 mg of P. gossypiella pheromone was tested in 1996 for mating disruption of both pests. Application of 625 ropes/ha caused a high level of suppression of mating of H. armigera females for at least 94 days and that of P. gossypiella females for 161 days. The pheromone release rates were c. 625 mg/day/ha for H. armigera and 162 mg/day/ha for P. gossypiella. A ‘long-life’ formulation of P. gossypiella pheromone, PBW rope LR, applied at 125 ropes/ha releasing 137 mg/day/ha achieved complete suppression of mating over 75 days. This release rate of P. gossypiella pheromone was much lower than that currently used in Israel (275 mg/day/ha). The present study indicates that mating of females of two moth pests with different pheromones can be disrupted by one combined formulation.
Evidence for the occurrence of sibling species inEubazusspp. (Hymenoptera: Braconidae), parasitoids ofPissodesspp. weevils (Coleoptera: Curculionidae)
Authors: Kenis M. , Mills N.J.
Published: July 2009

Comparative studies were made on three presumed sibling species of the genusEubazus, parasitoids of EuropeanPissodesspp. weevils, to clarify their taxonomy and define diagnostic characters. Several populations ofE. semirugosus(Nees),E. robustus(Ratzeburg) andEubazussp. were compared with respect to their morphology (mainly through morphometric analyses), fecundity, isoenzyme patterns and host preference. Crosses were made to assess the genetic and behavioural compatibility of the populations. In addition, the North AmericanE. crassigaster(Provancher), a parasitoid ofPissodes strobi(Peck), was compared toE. semirugosus, a species selected for introduction againstP. strobiin Canada. The ratio of the length of the ovipositor sheath to the fore wing length was the most discriminating morphometric variable, but discriminant analyses including several measurements were needed to completely separate European species. A canonical discriminant function provided a total separation between males ofE. crassigasterandE. semirugosus, but not between females.Eubazus crassigasterandE. semirugosuswere totally separated by the banding pattern of the enzyme phosphogluconate dehydrogenase whereas hexokinase and esterase provided a diagnostic separation betweenEubazussp. andE. robustus. Eubazussp. differed from all the other species by having a greater number of ovarioles and, consequently, a higher potential fecundity. In a two-choice oviposition test,E. semirugosusandEubazussp. showed a significant preference for their natural host,P. castaneusDe Geer andP. piceae(Illiger), respectively. A similar test made with their progenies reared under standard conditions showed that the difference in host preference was genetically fixed. Males and females of different species did not mate readily, in contrast to individuals from the same species. All attempts to interbreedE. robustusandEubazussp. failed, but a few crosses betweenE. semirugosusand the two other European species produced fertile offspring. These observations strongly suggest that the complex ofEubazusspp. parasitoids attackingPissodesspp. in Europe is composed of at least three sibling species, two of which appear to have specialized on distinct host species that occupy exclusive microhabitats.
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

Life 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

A 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

Spectral 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

Muscidifurax 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

Flight 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

Bacillus 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

Details 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

The 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

The 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

In 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.
Biological Notes on some Coccinellidae from East Africa
Authors: Vesey-FitzGerald Desmond
Published: July 2009

During the latter half of 1936 a search was undertaken for predators and parasites that might be of use against certain Coccidae which are causing considerable damage to the coconut crop in Seychelles.
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.
Simple Tests for estimating the Suitability of Mineral Oils as Mosquito Larvicides
Authors: David W. A. L.
Published: July 2009

In practice it is seldom found that any one of the numerous grades of oil prepared from crude petroleum is a satisfactory mosquito larvicide. The final product is almost invariably blended from several constituents. Each of the constituents may confer beneficial properties on the larvicide directly, or it may serve to correct undesirable features possessed by the other ingredients.

Even under world conditions which might be regarded as normal compared with those prevailing to-day, difficulties have confronted those who wished to select or blend a larvicide. There was firstly, in the remoter parts of the world, a lack of any specialised chemical apparatus ; secondly, the lack of a complete minimum performance specification by which to judge laboratory blends ; and thirdly, the difficulty arising from the fact that the specifications supplied for commercial grades of oil do not include data on many properties of the oil which are important to the malariologist but unimportant to the usual consumer.

This paper represents an endeavour to overcome the three difficulties outlined above. It provides a minimum performance specification for a larvicide and describes a series of simple tests which may be applied (a) to a commercially blended larvicide in order to establish whether this meets the requirements of the specification, and (b) to the individual ingredients (e.g., kerosines, Diesel oils or fuel oils) so that, in each case, the one with the most desirable combination of properties may be selected for incorporation in the final blend.
The macroscopic Differentiation of Anopheline Eggs according to their Pattern on the Surface of Water
Authors: Saliternik Z.
Published: July 2009

Thus far nine species of Anopheles have been found in Palestine. These, in order of frequency and importance, are : A. elutus, Edw., A. superpictus, Grassi, A. sergenti, Theo., A. multicolor, Camb., A. claviger, Mg. (bifurcatus, auct.), A. algeriensis, Theo., A. hyrcanus, Pall., A. pharoensis, Theo., and A. coustani, Lav. (mauritianus, Grp.).

The morphological characters of the eggs of these species have been described and are well known. Workers have, however, overlooked the fact that their eggs arrange themselves on water in specific patterns, determined apparently by their structure. Observations made during 1939–41 have shown that, if a number of eggs is placed on a drop of water, they assume a pattern characteristic of the species. This pattern arrangement makes possible a macroscopic differentiation of species in the field.

Observations have been made on ovipositions of all the species, but more particularly of A. elutus (188 ovipositions), A. sergenti (365 ovipositions), A. superpictus (149 ovipositions) and A. multicolor (51 ovipositions). These results indicate that these species arrange themselves into two types of patterns :—

i. Eggs arranged in parallel patterns. To this group belong those species that breed in open unshaded water : A. elutus, A. superpictus, A. multicolor.

ii. Eggs arranged in angular patterns, the eggs lying at an angle to one another, in the form of stars, etc. This group comprises the six remaining species, all of which prefer shaded places for their development.
A Tachinid parasitic on Plutella maculipennis, Curt.
Authors: Emden F. I. van
Published: July 2009

Dr. R. H. Le Pelley has reared in Nairobi a number of specimens of a new Tachinid from the diamond-back moth (Plutella maculipennis, Curt.).

Cadurcia plutellae, sp. n : ♂♀.

♂. Head black, the pollinosity of the face, lower half of the parafrontalia and lower half of the posterior orbits inconspicuous, but appearing almost silver-white in certain directions. Eyes bare. Frons one-fifth to one-sixth head-width (slightly less than one-half eye-width) above middle, very slightly dilated to vertex, moderately dilated to lunula ; face moderately dilated with the sides almost straight to the lower margins of the eyes, which are separated by half the head-width ; parafrontalia and interfrontalia somewhat narrowed to about middle, parallel-sided from there to base, the interfrontalia velvety blackish-brown, somewhat wider than the parafrontalia, the latter with about six inclinate and two reclinate setae, the parafacialia with 3–4 descending inclinate frontals, which reach the level of the apex of the second antennal joint. Antennae fuscous-black, third joint more than twice as long aswide, almost reaching level of lower eye-margins, falling short of mouth-margin by half its width, arista minutely pubescent, the hairs shorter than its basal diameter, the basal fourth moderately incrassate. Parafacialia one-half, jowls fully as wide as the third antennal joint, vibrissae level with mouth-margin. Palpi fuscous, hardly projecting beyond mouth-margin.
A Method of transporting living Mosquito Larvae
Authors: Lewis D. J.
Published: July 2009

Outbreaks of yellow fever in the Anglo-Egyptian Sudan and Uganda in 1940 emphasised the necessity for the mosquito control measures which are in force to prevent the disease from reaching Egypt or the East African ports. Edwards (1941, Mosquitoes of the Ethiopian Region, III, p. 3), referring to yellow fever, states that “ it would seem that most of the common biting mosquitoes of West Africa are to be regarded as potentially dangerous.” This statement applies also to north-east Africa. For the further planning of control measures, more information is required as to which mosquitos can act as vectors. Transmission experiments can usually be carried out only in a few specially equipped laboratories, so that mosquitos must sometimes be transported over great distances. A convenient method of doing this is to carry several thousands of living larvae which can provide a supply of adults for experiments. The writer has, for several years, used the simple method described below and found it effective in the hot dry climate of the northern Sudan. Recently it proved useful for sending larvae of species of Aëdes to the Yellow Fever Reseaich Institute at Entebbe.

Larvae are stranded on a wet surface in a cool damp atmosphere and can be carried under these conditions for many hours or even several days. Perforated trays are made from the metal of petrol tins as shown in Fig. 1. A piece of cloth 44 cm. square is laid over each tray and tied underneath it. Water containing the larvae is poured into the tray and drains away, leaving the larvae stranded. A metal cross-piece laid on the tray serves to support another tray above it. Eight trays can be placed in a four gallon petrol tin which is then closed with a lid. In hot weather a wet towel may be wrapped round the tin.
The relative Toxicity of Rotenone and Pyrethrum in Oil to the Argasid Tick, Ornithodorus moubata, Murray
Authors: Robinson G. G.
Published: July 2009

(1) Coal-tar phenols are useful intermediate solvents for making solutions of rotenone in both mineral and vegetable oils.

(2) Medium petroleum oil showed superiority to ground-nut oil as a carrier of rotenone in xylenol tested against Ornithodorus moubata.

(3) The solutions of rotenone in xylenol and oil showed no deterioration after storage in the dark at room temperature for six weeks.

(4) In these solutions rotenone proved far less toxic to Ornithodorus moubata than an equal weight of pyrethrin I in medium petroleum oil.
Residual Effect, Skin Application and Injection of γ-Hexachlorocyclohexane in Drosophila melanogaster
Authors: Dresden D. , Oppenoorth F. J.
Published: July 2009

As a basis for future investigations on the development and the nature of resistance against insecticides, the regression lines for the toxicity of γ-hexachlorocyclohexane to D. melanogaster were estimated by means of

1. A contact method, in which the insects (adults) were exposed to a treated surface.

2. A skin-application method, in which measured doses of an acetone solution of the poison were used.

3. An injection method in which adults were injected with known doses of an emulsion containing the insecticide.

The reproducibility of the results obtained with the above methods is briefly discussed. It was found that in the case of the skin-application and injection methods the regression line did not deviate significantly from linearity. The same was true for the contact method if the results obtained with the smaller doses were not taken into consideration.
A Note on the prepupal Stage and the external Sex Characters of the Pupae of Anobium punctatum (Deg.) (Coleoptera, Anobiidae)
Authors: Bletchly J. D.
Published: July 2009

External characters enabling the sexes to be distinguished readily in the adult Anobium punctatum (Deg.), popularly known as the common furniture beetle, have been described by Kelsey & others (1945) but no account has yet been published of the external sex characters of the pupae of this Anobiid. In the course of research at the Forest Products Research Laboratory on the biology of this species, a series of larvae in the prepupal stage and of pupae have been examined to determine whether the sexes can easily be recognised in the immature stage. Sex determination, before the adult stage is reached, is of great value for expermental work on breeding techniques and other projects.
The Larvae and Pupae of some important Lepidoptera
Authors: Williams J. R.
Published: July 2009

The larvae and pupae of the following Lepidoptera, all of which are of economic importance in Mauritius and most of them elsewhere also, are described:—

The Agrotids, Sesamia calamistis Hamps. and S. inferens (Wlk.); the Crambids, Proceras sacchariphagus Boj. and P. indicus Kapur (larva only); and the Olethreutids, Argyroploce schistaceana (Snell.), A. leucotreta Meyr., Cryptophlebia peltastica (Meyr.) and C. williamsi Bradley.
The Sandflies (Phlebotominae) of Iraq
Authors: Pringle Gordon
Published: July 2009

An account is given of a survey of the sandfly fauna of Iraq made in 1949 and 1950. Two new species, one of which has been previously misidentified, and two new varieties are described, and brief notes are given on all the 12 species of Phlebotomus and Sergentomyia taken in the survey. A description is given of a male of P. palestinensis taken in Baghdad, as it differs from the male described from Jericho. Keys to the Phlebotominae in Iraq and neighbouring territories are included, together with a Table showing their distribution.

Relationship between distribution of human dermal leishmaniasis and the species of Phlebotomus is shown on a map, supporting the belief that P. sergenti is the principal, if not the sole, vector of oriental sore in Iraq.

The distribution of Sergentomyia is given in another map indicating that, in contrast to Phlebotomus, the individual species of Sergentomyia are confined to one or other side of the boundary between the Saharo-Sindian and the Irano-Turanian zoogeographical regions.
The Biology of the Coconut PestMelittomma insulare(Col., Lymexylonidae), and its Control in the Seychelles
Authors: Brown E. S.
Published: July 2009

The biology ofMelittomma insulareFairm. (Coleoptera, Lymexylonidae), a wood-boring pest of coconuts in the Seychelles and northern Madagascar, has been studied from all angles, with the object of discovering practical means of control.

The stages in the life-history are figured and briefly discussed, supplementary details being given to the earlier accounts of Vesey-FitzGerald and others.

The feeding habits of the larvae ae described in some detail, with particular reference to their association with micro-organisms which were almost invariably detected in infested wood surrounding the tunnels. The larva is shown to feed on fluid extracted from the parenchymatous tissues and not on solid wood.

The course of the development of an infestation in an individual trunk is described in detail, culminating in the fall of the palm. Variations in this process are correlated with the age of the palm and other factors. The spread of infestations through plantations and islands is also discussed. A detailed account is given of the symptoms shown by attacked palms, together with a critical revision of certain changes which have in the past been attributed toMelittommaattack.

An account is given of the occurrence ofM. insularein certain palms other than coconuts, in which it has been found.
Studies on the Responses of the Female Aëdes Mosquito. Part VI.—The Attractiveness of coloured Cloths to Canadian Species
Authors: Brown A. W. A.
Published: July 2009

A series of 32 cloths, including 8 flannels dyed to Munsell standard colours, seven coloured satins and 17 service fabrics, were tested for their attractiveness to northern Canadian Aëdes mosquitos, and were assessed for their reflectivity of visible and ultra-violet light.

Their attractiveness was found to vary inversely with their reflectivity or brightness, although the different textures represented in the series tended to obscure the generalised relationship.

When comparisons were made within a series of identical texture, the correlation was good in the range between 475 and 625 mμ wave-length, but was not present in the red or infra-red, nor in the violet and ultra-violet ranges of wavelength.

Green tended to be less attractive, and white more attractive, than was expected from this relationship. For colour values of similar lightness or darkness, the order of attractiveness to Aëdes punctor and associated species was black, red, blue, brown, green, white, yellow.
Studies of the Life History and Ecology of the Ant Oecophylla longinoda Latreille
Authors: Way M. J.
Published: July 2009

In British East Africa Oecophylla longinoda (Latr.) var. textor Santschi is locally common in the costal region. Inland it is absent from higher altitudes and from areas where there is a pronounced dry season.

In Zanzibar Island, O. longinoda at least 89 species of trees and shurbs; the largest populations occur on the clove (Jambosa caryophyllus), Citrus spp., Bridelia micrantha and Canthium zanzibaricum.

The nesting habits and colony composition of O. longinoda are such that one colony may spread over a number of adjacent trees; it contains only one gravid queen.

Winged virgin sexual forms are released at the beginning of the wet seasons and new colonies are initiated by a single queen, who uses her food reserves to bring the first batch of brood to maturity.

In Zanzibzr, O. longinoda tends a wide range of Homoptera that produce honey-dew, but apparently “ prefers ” certain Coccids, notably Saissetia spp.

The degree of attention afforded by an ant species determines the species of Homoptera which it is able to attend.

The insect species preyed upon by O. longinoda include the honey bee, Apis mellifera, and the driver ant, Dorylus nigricans, of which large numbers may be destroyed.

O. longinoda is of undoubted value for controlling certain coconut pests, notably Theraptus sp. (Coreidae), and its efficiency in coconut plantations could probably be much enhanced.
Studies on the Association of the AntOecophylla longinoda(Latr.) (Formicidae) with the Scale InsectSaissetia zanzibarensisWilliams (Coccidae)
Authors: Way M. J.
Published: July 2009

A close association exists between the antOecophylla longinoda(Latr.) and the scale insectSaissetia zanzibarensisWilliams.

Several factors cause the scale to be rare in the absence of the ant. Contamination by honey-dew and sooty moulds prevents increase of theS. zanzibarensispopulation above a relatively low level, while, in addition, insect parasites and probably predators virtually exterminate the scale. A fungal parasite may destroy honey-dew-contaminatedS. zanzibarensisunder humid conditions.

The attendantO. longinodaprevents contamination of the scale by honeydew. It gives absolute protection from Coccinellid predators and, although parasitism byCoccophagusspp. and predation byEublemmaspp. is not prevented, the mortality ofS. zanzibarensiswhich they cause is thought to be of little significance.

O. longinodaworkers benefitS. zanzibarensisin other ways. They remove débris from the scale clusters; they transport the nymphs and establish them at suitable feeding sites. The effect of these benefits is most marked when the ant population is high relative to that of the scale.

The silken shelters built byO. longinodaoverS. zanzibarensisclusters protect the ant during adverse weather and may only incidentally benefit the scales.

S. zanzibarensisand other honey-dew-producing Homoptera are the major food source forO. longinoda. Other sources are sufficient to maintain only relatively low populations of the ant.
An additional Note on the Fauna of Birds' Nests in Britain
Authors: Woodroffe G. E.
Published: July 2009

In an earlier paper (Woodroffe, 1953) full details were given of the results of a survey, the purpose of which was to study the insects and mites which inhabit certain birds' nests in Britain. Since then further work has been carried out on certain species, and, as a result, one or two statements made in the earlier publication now require correction or modification.
Temperature Coefficients of Insect Kill by volatile solid Insecticides
Authors: McIntosh A. H.
Published: July 2009

Three volatile solid insecticides (DFDT, γ BHC and aldrin) were tested against two species (Oryzaephilus surinamensis and Tribolium castaneum) at two temperatures (30°C. and 11°C.) in simple laboratory fumigation tests. DFDT killed both species faster at 11°C. than 30°C.; γ BHC killed O. surinamensis faster at 11°C. than 30°C., but T. castaneum faster at 30°C. than 11°C.; aldrin killed both species faster at 30°C. than 11°C.
The Pick-up of Spray Droplets by flying Locusts
Authors: Wootten N. W. , Sawyer K. F.
Published: July 2009

Measurements of the Horizontal Equivalent Area (HEA) of flying locusts and the toxic efficiency of Mk. IV DNC solution, as a function of spray droplet size, have been made using Schistocerca gregaria (Forsk.) flying “ naturally ” in a wind tunnel. The experimental conditions, including visual stimuli, for “ natural ” flight were determined by means of a flight balance. The observed values of locust airspeed varied from 2·5 to 6·5 metres per second with a mean value of about 3·2 metres per second.