bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on acaricide resistance in Rhipicephalus evertsi evertsi Neumann (Acarina: Ixodidae) in East Africa. Identification and inheritance of a resistance factor to organochlorines
Authors: Lourens J. H. M. , Tatchell R. J.
Published: July 2009

Difficulties were experienced in determining the susceptibility status of populations of Rhipicephalus evertsi evertsi Neum. to organochlorine acaricides. A susceptible strain of this species was found at Maswa, Shinyanga District, Tanzania. Susceptibility for toxaphene, dieldrin and γ–BHC was assessed by means of an FAO recommended test method, the oil-based packet test. A homogeneously responding resistant strain was built up from larvae from Ngong, near Nairobi, Kenya, that had survived a discriminating dieldrin concentration of 0·2%. These showed resistance factors of 10·8 for toxaphene, 30 for γ-BHC and 95 for dieldrin. The F1 cross between susceptible and resistant populations responded homo-geneously and was intermediate in resistance between the parental strains, with resistance factors of 8·7, 9 and 8·1 for ithese compounds, respectively. Larvae from backcrosses of F1 adults with the parental strains showed stepped ld-p lines such as would be expected in a case of inheritance of a single gene allele with partial dominance for resistance. A population of R. e. evertsi near Dar es Salaam, Tanzania, was controlled by application of 0·3% toxaphene despite it having resistance factors similar to those of the F1 hybrids.
Aspects of the feasibility of employing odour-baited traps for controlling tsetse flies (Diptera: Glossinidae)
Authors: Hargrove J. W. , Vale G. A.
Published: July 2009

Catches of Glossina morsitans morsitans Westw. and G. pallidipes Aust. attracted to an odour-baited trap in riverine woodland in Rhodesia declined by about three-quarters over a 50-day period in the hot dry season. Concurrent catches from refuges suggested that the decline in trap catches was due to a reduction in population densities rather than a decreasing responsiveness of tsetse to the trap. Of G. pallidipes marked and released 250, 1250 and 2250 m from the trap, the percentages recaptured in the trap after 5 days were about 20, 10 and 4, respectively, and after 40 days about 28, 15 and 13. The sustained responsiveness to the trap and efficiency with which marked flies were removed suggested that odour-baited traps at an economical spacing of roughly one per 10 km2 could produce effective control of G. pallidipes.
Further laboratory and field evaluations of experimental baits to control leaf-cutting ants (Hymenoptera: Formicidae) in Brazil
Authors: Phillips F. T. , Etheridge P. , Martin A. P.
Published: July 2009

Four features concerned with the baiting of leaf-cutting ants were studied. A liquid concentrate containing attractive and arrestant substances together with a toxicant was developed for the production on site of cheap baits for leaf-cutting ants in Brazil by addition to suitable locally available particulate carrier materials (matrices). The five non-organochlorine insecticides that performed best in previous baiting trials were further tested in Brazil at slightly higher concentrations against Atta cephalotes (L.), which had been shown to be the most difficult species to eradicate; two of these showed promise as substitutes for the well-proven but persistent organochlorine insecticide mirex. Other tests showed that bait widely scattered over a nesting site containing colonies of A. sexdens (L.), in simulation of a broadcast application from aircraft or ground dispensers, was as effective as that placed by hand at entrance holes of nest mounds. Weathering tests in a forest area showed that spoilage by rain and fungal growth, not loss of insecticide, were the main factors governing the effective life of dried citrus pulp baits under wet or humid conditions.
Probable natural hybrids of Nephotettix virescens (Distant) and N. nigropictus (Stal) (Hemiptera: Cicadellidae) from Sabah, Malaysia
Authors: Ramakrishnan U. , Ghauri M. S. K.
Published: July 2009

Hybrids of Nephotettix virescens (Dist.) and N. nigropictus (Stål) have been bred in the laboratory, and they could transmit rice tungro virus even though only one of the parents is a vector. In the present paper, evidence is presented based on coloration and on male genitalia that suggests that such hybrids occur in nature. The potential danger from such hybrid vectors is pointed out, and taxonomists are alerted to the risk of accepting such hybrids as new species, thus completely hiding their potential as vectors.
The biology and pest status of cereal aphids (Hemiptera: Aphididae) in Europe: a review
Authors: Vickerman G. P. , Wratten S. D.
Published: July 2009

The biology and pest status of the common species of Sitobion, Metopolophium and Rhopalosiphum found on wheat, barley and oat crops in Europe is critically reviewed. After preliminary sections on species and sampling, the factors that induce the production of the different morphs of cereal aphids are considered. Basic life-cycles are described and the importance of migration and dispersal considered. Host-plant preferences, survival and reproduction on different Gramineae, and feeding site preferences are considered, particularly in relation to the type and amount Of damage caused by the aphids. The effects of constant temperatures on the biology of some species have been investigated, but little is known about the effects of weather in the field. There have been few quantitative studies on the effects of natural enemies on cereal aphids, but the evidence suggests that they may be important in reducing their numbers. Side-effects of pesticides and fertilisers on aphids are also discussed. Aphids may reduce grain yield and quality. Direct damage may result from reductions.
Studies on the sibling species Anopheles gambiae Giles and Anopheles arabiensis Patton (Diptera: Culicidae) in the Kisumu area, Kenya.
Authors: Highton R. B. , Bryan Joan H. , Boreham P. F. L. , Chandler J. A
Published: July 2009

A study was undertaken of the seasonal abundance, feeding habits, resting habits and malaria infection rates of the sibling species Anopheles gambiae Giles and A. arabiensis Patton on the Kano Plain, Kenya, and the surrounding foothills. A. arabiensis was the dominant species on the plains and A. gambiae in the foothills. A. gambiae was highly anthropophilic with 92% feeding on man, whereas 59% of A. arabiensis fed on cattle. In both species, the choice of host was affected by the availability of cattle. A. arabiensis rested out of doors more commonly than A. gambiae. The sporozoite rate in A. gambiae was 5·33%, 15·98 times higher than the rate of 0·33% found in A. arabiensis.
Toxic bait for the control of Anoplolepis longipes (Jerdon) (Hymenoptera: Formicidae) in the Seychelles. II. Effectiveness, specificity and cost of baiting in field applications
Authors: Haines I. H. , Haines J. B.
Published: July 2009

Bait containing 1% a.i. aldrin and used at a rate of 10 kg/ha gave good control of Anoplolepis longipes (Jerd.) in the Seychelles, especially when large areas were treated. Typically, 90% or more of the ants were killed, usually within the first few days. Depending on the area baited, population recovery took at least 3–12 months and was largely by re-invasion from untreated areas. The bait was relatively specific but chickens starved for 24 h would eat it when no other food was available. It is concluded that baiting is relatively inexpensive and provides a safe method of controlling infestations of A. longipes over large areas.
Overwintering and spring emergence of Heliothis armigera (Hübner) (Lepi–doptera: Noctuidae) in the Namoi Valley, New South Wales
Authors: Wilson A. G. L , Lewis T. , Cunningham R. B.
Published: July 2009

The overwintering of Heliothis armigera (Hb.) was studied in the Namoi Valley, north-western New South Wales, Australia. In field observations, over 80% of pupae formed during late April and May were found to be in diapause and did not resume development until September. Moth emergence from diapausing pupae occurred in a protracted period between September and November. Laboratory studies indicated the probability of two phases of diapause development, one completed under cool soil conditions of winter and a second requiring a temperature above about 17° C. The threshold of the second phase was higher than that for non-diapausing pupae and was not normally reached until late September. The times to diapause termination in populations of overwintering pupae were satisfactorily fitted to a geometric distribution, which was reflected in the protracted emergence period of moths in field cages. The limited availability of suitable host-plants for the overwintering generation and for emerging moths is discussed.
Monitoring wheat bulb fly, Delia coarctata (Fallén) (Diptera: Anthomyiidae), with light-traps
Authors: Bowden John , Jones Margaret G.
Published: July 2009

The flight activity of adult Delia coarctata (Fall). was studied on Rothamsted Farm from 1969 to 1977 using light-traps. These catch, almost exclusively, dispersing mature females, more being caught at full moon than at new moon. Dispersal begins in response to an acceleration in the rate of decrease of daylength, and at Rothamsted begins on 10 July, soon after the rate of decrease accelerates. Maturation of eggs is controlled by temperature; at Rothamsted, the first mature females appear when temperature accumulation above 5° C has reached 314·5±10·5° after 12 June. Maturation usually coincides with dispersal, but females that have matured before 10 July do not disperse until after that date. Catches of females in light-traps are correlated with the numbers of emerging females per hectare and the numbers of eggs per hectare. Light-traps could be used as a simple way of forecasting numbers of eggs early enough to give advice on seed treatment for winter wheat on land subject to attack by D. coarctata.
Descriptions and host ranges of the sorghum midge, Contarinia sorghicola (Coquillett) (Diptera: Cecidomyiidae), and of eleven new species of Contarinia reared from Gramineae and Cyperaceae in Australia
Authors: Harris K. M.
Published: July 2009

Detailed taxonomic studies of adult Cecidomyiidae reared from inflorescences and seed-heads of species of Gramineae and Cyperaceae during field surveys in Queensland and the Northern Territory of Australia in 1970–73 established that Contarinia sorghicola (Coq.) is restricted to non-indigenous crop and weed species of Sorghum section Sorghum that have been introduced to Australia by man and that three morphologically distinct species of Contarinia occur on native Australian grass species of Sorghum section Parasorghum. An earlier report that the wild grasses Dichanthium, Bothriochloa and Eriochloa serve as alternative hosts of C. sorghicola was not confirmed by detailed examination of long series of specimens reared from these hosts, nor was the pest species found on any other genera of Gramineae. It is therefore concluded that, in Australia, C. sorghicola has been spread (probably in contaminated seed) and maintained by grain and forage sorghums and that wild grasses are not potential sources of crop infestation. Eleven new species are described: C. roperi sp. n. and C. plumosi sp. n. from Sorghum plumosum; C. intrans sp. n. from S. intrans and S. stipoideum; C. sehimae sp. n. from Sehima nervosum; C. bothriochloae sp. n. from B. bladhii; C. dichanthii from D. annulatum var. fecundum and D. tenuiculum and possibly from D. affine and D. sericeum; C. passlowi sp. n. from D. annulatum var. fecundum; C. alloteropsidis sp. n. from Alloteropsis semialata; C. brevipalpis sp. n. from Eragrostis brownii; C. scirpi sp. n. from Scirpus lacustris and C. fimbristylis sp. n. from Fimbristylis bisumbellata. Characters of the female cerci were especially useful in diagnosing species, making it easier to identify females than males. Cecidomyiids of the genus Geromyia were reared from Setaria and cecidomyiids of the genus Lasioptera were reared from ten grass genera and one sedge genus during the surveys, but this material is not dealt with in detail. The needs for further field work and taxonomic studies are stressed and it is suggested that apertures on the dorsal surface of abdominal segment VIII in female C. sorghicola may be the openings of sex pheromone glands and would merit further detailed investigation.
The Aphid of tea, coffee and cacao (Toxoptera coffeae, Nietner)
Authors: Theobald Fred. V.
Published: July 2009

Nietner in 1880 (“ The Coffee Tree and its Enemies ”) described an Aphis from coffee found in Ceylon and Java as Aphis coffeae. The description is as follows:—“ Both sexes naked, shiny pitch-black with whitish rostrum and legs and greenish abdomen. The rostrum reaches beyond the base of the second pair of legs. The antennae are 7-jointed, the first, second and sixth being short, the rest long, the two basal joints are black, the rest are whitish, black towards apex. Legs with femora and tarsi nearly black, tibiae nearly white, hind legs with base of tibiae slightly curved. Male four-winged, with black stigma in the upper ones. Female apterous. Abdomen in both sexes 2-corniculate and with an anal tube. Size moderate. Young individuals light coloured.” Apparently the male and female described refer to the alate viviparous and apterous viviparous female.
Malathion resistance conferred by a carboxylesterase inAnopheles culicifaciesGiles (species B) (Diptera: Culicidae)
Authors: Malcolm C. A , Boddington R. G.
Published: July 2009

A strain ofAnopheles culicifaciesGiles (species B) originally collected from Aurangabad, Maharashtra State, India, showed highly specific resistance to malathion. Homogenates of one-day-old adults metabolized14C-labelled malathion at a level comparable with strains ofA. stephensiListon andA. arabiensisPatton known to possess the malathion carboxylesterase resistance mechanism and at a higher rate (6.4 and 7.8 times, respectively) than malathion-susceptible strains of these species. The major metabolite obtained was malathion dicarboxylic acid, a carboxylesterase product, which suggests that this may be the principal resistance mechanism in this strain. Levels of non-specific esterase activity in larvae and adults were similar to those shown by both the susceptible and resistant strains ofA. stephensi, implying that no quantitative increase in esterases had occurred. Microtitre plate assays on individual mosquitoes provided no evidence for the presence of the insensitive acetylcholinesterase resistance mechanism.
Biology of Bruchus dentipes Baudi (Coleoptera: Bruchidae) on Vicia faba and a method to obtain gravid females during the imaginal quiescence period
Authors: Tahhan O. , Van Emden H. F.
Published: July 2009

Bruchus dentipes Baudi was found to have four larval instars, and the sex ratio was very close to 1:1. Both sexes fed on pollen and nectar of faba beans (Vicia faba) for seven days before and throughout the oviposition period of the females, which was about 33 (range 26–40) days. The beginning and peak of oviposition were influenced by the phenology of the crop, particularly flowering and pod-setting dates, but also temperature. Females laid an average of 123 (range 28–310) eggs, and the end of the adult life in the field came in May when the pods had matured. In different years, peak oviposition occurred on different dates in April when the pods were still all green. During the quiescence period in the winter, females obtained from wetted seeds were fed with different diets in the laboratory, but only those supplied with faba bean flowers laid eggs. No major adult mortality occurred in seeds harvested in May and stored until the end of March of the following year, after which mortality rose steeply till all adults had died by early June. Therefore, storing seeds and delaying their planting till the following year will ensure 100% adult mortality. As the seeds remain viable, such storage is one method for reducing infestation in the field. Mortality of larvae in the stored seeds was from cannibalism when two larvae met at the same tunnel (10%), from the mite Pyemotes tritici (Lagrèze-Fossat & Montagné) (11%), from the braconid larval parasite Triaspis thoracicus (Curtis) (2%) and from unknown reasons (5%).
Resistance of faba bean, Vicia faba, to Bruchus dentipes Baudi (Coleoptera: Bruchidae)
Authors: Tahhan O. , Van Emden H. F.
Published: July 2009

Field screening experiments for resistance of faba bean (Vicia faba) to Bruchus dentipes Baudi in Syria between 1982 and 1985 involved about 1000 accessions and indicated that only phenological resistance was present. Two accessions were chosen, on the basis of seed infestation with larvae, for further study. The two accessions (BPL33 and ILB1814) were tested against natural infestations as well as under four levels of bruchid infestation and at two different times of release of adults. BPL 33 maintained its resistance (about 50%) in relation to ILB1814 under these different conditions, except when adults were released at a time when both accessions carried pods simultaneously. This confirms that the resistance of BPL33 was phenological, related to late flowering and late pod setting. An intergrated control approach is there fore suggested.
Ticks (Acari: Ixodoidea) of the Yemen Arab Republic. II. The Rhipicephalus sanguineus (Latreille) group
Authors: Pegram R. G. , Zivkovic Danica , Jongejan F.
Published: July 2009

Triks of the group of Rhipicephalus sanguineus (Latreille) in 423 total monthly collections taken from camels, cattle, donkeys, sheep and goats between September 1978 and August 1979, and in a few miscellaneous collections, from the Yemen Arab Republic were examined. Adult ticks of three species in the group were identified: R. camicasi Morel, Mouchet & Rodhain, R. turanicus Pomerantsev and R. sanguineus s.s. Host relationships and ecological affinities were analysed. R. sanguineus s.s. occurred rarely, only on dogs. R. turanicus occurred on all host species including dogs but more frequently on cattle and camels. It was collected from both dry and wet habitats but was taken regularly at only one wetter site. R. camicasi, the most common species in the group, occurred at most collecting sites on all host species except dogs. Overall, the numbers of R. sanguineus group ticks were low throughout the country and no seasonal patterns could be detected.
Some factors affecting the reliability of pheromone traps for measurement of the relative abundance of Helicoverpa punctigera (Wallengren) and H. armigera (Hübner) (Lepidoptera: Noctuidae)
Authors: Wilson A. G. L. , Morton R.
Published: July 2009

Experiments were conducted in a cotton field in north-western New South Wales to determine the effect of pheromone trap design and placement on the catch of Helicoverpa punctigera (Wallengren) and H. armigera (Hübner) adults in paired traps. A cone trap design was found to give consistently larger catches of moths than two funnel trap designs. Furthermore, lower efficiency of catch of H. punctigera tended to bias relative catches in the funnel traps towards H. armigera. In comparison to the ratios of the two species in egg samples from the field, the cone trap did not show much bias to either species of moth. Traps located 40 m inside a cotton field showed larger catches and reduced variation compared with egg species ratios than traps placed at the edge of the field. Wind speed and direction and insecticide application also affected the catch in the traps. The catch data tended to become unreliable after the end of February, possibly due to changes in crop attractiveness for oviposition. It was found that the less numerous moth species at a given time still tended to be over-represented in pheromone traps in comparison to the ratios in egg counts. A linear time trend was introduced to compensate for the bias. The use of the traps shows promise in determining the relative abundance of the two species for use in resistance management strategies and other purposes.
Feeding responses of the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), to resistant and susceptible host-plants
Authors: Padgham D. E. , Woodhead S. , Rapusas H. R.
Published: July 2009

The feeding responses, growth and population development of Nilaparvata lugens (Stål) are quantified on a range of twelve susceptible or resistant host-plants. Paris of rice varieties carrying the Bph1, bph2 and Bph3 resistance genes are compared as hosts for N. lugens, and it is concluded that such notations do not adequately describe the diversity of plant resistance mechanisms. Evidence is presented for resistance mechanisms involving enhanced insect activity and gustatory responses to unacceptable phloem.
The responses of individual males in an isolated population of Glossina morsitans morsitans Westwood (Diptera: Glossinidae) to pheromone-baited decoy ‘females’
Authors: Hall Martin J. R. , Langley Peter A.
Published: July 2009

The responses of individually marked males of Glossina morsitans morsitans Westwood to decoys (9 × 3-mm rectangles of 2-mm-thick brushed nylon) baited with sex pheromone (15,19,23-trimethylheptatriacontane) were studied after their release onto an island in Lake Kariba, Zimbabwe. Some 45–60% of resighted flies were seen on decoys, the percentage being greater for flies released at an older age. For flies released on emergence, the mean age at first contact with decoys on a static screen was 6.6 days, an average of four days later than their first observed contact with a bait ox. There was great variability in the response towards decoys on successive contacts. In general, the intensity of the responses to decoys in the first minute after contact (the ‘pre-copulatory’ responses) decreased from one enounter to the next in a single 1–2-h observation session, but were restored to high levels after an interval of several hours. The intensity of responses towards decoys after this initial period (the ‘copulatory’ responses) were not affected by previous contacts. Neither previous sexual experience nor age at first contact affected the durations of response on decoys. There were no differences between the responses of wild flies and those from a laboratory colony. The results are discussed in relation to the use of decoys with chemosterilant for tsetse autosterilization. Over 60% of flies contacting decoys did so more than once, which would increase, cumulatively, the chances of their being sterilized.
Sexual responses of males of Glossina morsitans morsitans Westwood and G. pallidipes Austen (Diptera: Glossinidae) to traps and targets in the field
Authors: Wall Richard
Published: July 2009

Studies were conducted in Zimbabwe to determine the nature and degree of sexual responses of males of Glossina morsitans Westwood and G. pallidipes Austen around host animals, traps and targets. Males of both species, after being attracted, appeared to accumulate around a stationary bait. This was supported by observations of concentrations of unfed males of G. m. morsitans on bait animals and unfed males of G. pallidipes on the surrounding ground. Nutritional analysis confirmed that traps attract males with a range of hunger states but catch mainly hungry males of both species. Movement of electrified targets significantly increased the catches of both sexes of G. m. morsitans but not of G. pallidipes. Artificial female-mimicking decoys made from black felt sewn onto electrified targets significantly increased the numbers of G. m. morsitans males caught when the targets were stationary and of G. pallidipes males when they were moving. The electrified targets caught a higher proportion of males of both species than traps, most probably as a result of their killing the males accumulating around the target in search of virgin females. The results show that the behaviour of relatively well-fed males attracted to host animals, traps and targets does appear to have a sexual component in both G. m. morsitans and G. pallidipes and that it may be possible to exploit the sexual responses of males to increase capture efficiency further. However, targets may have far greater potential for such manipulation than traps.
Preliminary investigation of the mechanisms of DDT and pyrethroid resistance in Culex quinquefasciatus Say (Diptera: Culicidae) from Saudi Arabia
Authors: Amin A. M. , Hemingway J.
Published: July 2009

High levels (>1000-fold) of resistance to DDT, permethrin and deltamethrin were detected in Culex quinquefasciatus Say from Saudi Arabia. Biochemical enzyme and metabolic studies indicated that there is evidence for a metabolic basis to both the organochlorine and pyrethroid resistances. Electrophysiological studies indicated that there is no kdr-type mechanism conferring resistance to the pyrethroid lambda-cyhalothrin neurophysiologically, although there is evidence of cross-resistance between DDT and the pyrethroids by bioassays. There was a change in the oxidase system in both the DDT- and permethrin-selected strains and an increase in glutathione transferase activity in the DDT-selected line. Metabolic studies indicated that both oxidases and glutathione transferases are involved with DDT resistance as DDA and DDE were the predominant metabolites after a 5-h in-vitro incubation period. Permethrin resistance is likely to involve an increase in oxidative degradation, but further metabolic studies are needed to confirm this.
Copidosoma graminis sp. n. (Hymenoptera: Encyrtidae), a polyembryonic parasitoid of armyworms (Lepidoptera: Noctuidae) in Australia
Authors: Noyes J. S.
Published: July 2009

Copidosoma graminis sp. n., a polyembryonic encyrtid parasitoid of armyworm pests of gramineous crops and pasture in Australia, is described and compared with related species. The parasitoid plays an important role in the natural control of these pests in Australia.
Graft-transmissibility of resistance to cowpea aphid, Aphis craccivora Koch (Hemiptera: Aphididae), in six highly antibiotic cowpea varieties
Authors: Ansari A. K. , van Emden H. F. , Singh S. R.
Published: July 2009

The use of six cowpea varieties highly resistant to Aphis craccivora Koch in grafts (as resistant scion and rootstock) with the susceptible variety Prima indicated the presence of a graft-transmissible chemical involved in the resistance. Wrapping the resistant part in light-proof foil indicated that photosynthesis is involved in the production of the chemical. In a third test, intergrafting is involved in the production of the chemical. In a third test, intergrafting the resistant part with and without leaves confirmed the importance of photosynthesis in the transfer of resistance. Finally, covering the resistance intergrafts with foil showed that the accumulation of the chemical in the stem before the foil was applied was the major source of the graft-transmissible resistance.
Laboratory colonization of the tsetse fly Glossina pallidipes Austen (Diptera: Glossinidae) using an in vitro feeding method
Authors: Langley P. A.
Published: July 2009

Attempts to establish a laboratory colony of Glossina pallidipes Austen from adults and puparia of Uganda origin (Lugala) sent from a colony previously established in Amsterdam have been highly successful. Flies are maintained at 25 ± 0·5°C, L:D 12:12 and 85% RH. They are fed six days per week on whole defibrinated pig blood collected aseptically and irradiated at 1·5 kGy before storage at 4°C. The blood is presented through silicon rubber membranes at 37°C. Virgin female flies are mated when 7–9 days old with equal numbers of 9–12-day-old males in a 30 × 30 × 10-cm cage covered with white Terylene netting and illuminated with a fluorescent light from above, providing 300–500 lux on the cage bottom. The sexes are left together for 40–48 h, during which time they are offered food twice. After separation of the sexes, 30 females are housed in a cage 15 cm in diameter and two males are added. Flies are kept for 90 days before discarding. The establishment of this colony is discussed in terms of the mating behaviour of the species, highlighting differences in the laboratory between G. pallidipes from Uganda and Zimbabwe and between G. pallidipes and G. morsitans morsitans Westwood.
Associations between host-plant nitrogen and infestations of the sugarcane borer, Eldana saccharina Walker (Lepidoptera: Pyralidae)
Authors: Atkinson P. R. , Nuss K. J.
Published: July 2009

Infestations of Eldana saccharina Walker in South Africa are higher in intensively-grown than in peasant-grown sugarcane, and are worse in water-stressed plants. Although field trials showed negligible increases in the incidence of the pest with applied nitrogen, the degree in which the degree of water stress could not be controlled. Pot-plant trials, in which the degree of water stress was controlled as well as the amount of fertilizer, showed that the combination of nitrogen with stress resulted in increased survival of larvae and greatly increased biomass with shortened development times. Adults did not appear to choose stressed or fertilized plants in preference to normal or unfertilized ones. In every case, whether in the field or in insectary trials, increased infestation levels were associated with increased stalk total nitrogen. Amino acid determinations showed that the balance of individual acids did not appear to alter but that the balance of individual acids did not appear to alter but that glyphosate ripener had a similar effect to water stress, increasing all amino acids together. Infestations in older cane were disproportionately higher than in younger cane, weight for weight, despite reduced levels of stalk nitrogen. This anomaly may be due to the presence of phenolic compounds in younger cane, or in cane tops. Levels of nitrogen are much higher in the feeding sites of the insect in natural host-plants than in cane stalks, and the fecundity of feral moths natural hosts appeared to be higher than that of moths from sugarcane. The insect appears to have invaded sugarcane when stalk nitrogen levels reached sufficiently high levels for its survival as a result of intensive cultivation.
Myosoma nyanzaensis sp. n. (Hymenoptera: Braconidae) parasitic on the stem-borer pest Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) in Kenya
Authors: Quicke Donald L. J. , Wharton Robert A.
Published: July 2009

Myosoma nyanzaensis sp. n. is described and illustrated, and is distinguished from the only other known Old World species, M. chinensis (Szépligeti) comb. n. (= Bracon chinensis Szépligeti). M. nyanzaensis is the first species of the genus to be described from the Afrotropical Region, where it has been reared as a gregarious ectoparasitoid of larvae of the pyralid moth Chilo partellus (Swinhoe) infesting maize and sorghum.
The influence of adult size and protein diet on the human-oriented behaviour of the bush fly, Musca vetustissima Walker (Diptera: Muscidae)
Authors: Tyndale-Biscoe Marina
Published: July 2009

Adults of Musca vetustissima Walker that were caught when attracted to humans in the field responded positively in a later test when a hand was inserted in a cage, both in terms of proportion responding and time spent on the hand. Flies with a similar adult diet, whether of culture origin or the first-generation offspring of field-caught flies, responded similarly to the hand in the cage provided they were of similar size. A larger proportion of small flies than of large ones came to the hand, and stayed for longer periods. Large protein-deprived and dung-fed (suboptimal protein) flies had a nuisance value between 28 and 35 times as great as large blood-fed flies, while small blood-fed flies had a nuisance value 18 times as great. The nuisance value of small protein-deprived and dung-fed flies was between 61 and 67 times as great. Residence period on the hand increased with time in large protein-deprived flies but not in flies in the other categories tested. Few flies responded to the hand during the first 15 day-degrees C post eclosion, or when gravid or nearly gravid; the most responsive flies were in ovarian stages 0B, 1, 2 and 3. The implications of these results are discussed in terms of the fly nuisance levels experienced in south-eastern Australia.
Population dynamics of the sugarcane borer, Eldana saccharina Walker (Lepidoptera: Pyralidae), in Natal, South Africa
Authors: Atkinson P. R. , Carnegie A. J. M.
Published: July 2009

Infestations of the sugarcane pest Eldana saccharina Walker have been consistently serious in one part of the cane-growing belt of Natal, South Africa. Mortality in this region over seven years was estimated from moth catches in light traps, checked against population change measured from extensive larval counts, and plotted against climatic indices. The object was to construct a predictive model to illustrate mortality in other regions of the cane belt, to which infestations have spread in recent years. The spread southwards along the coast did not seem to have resulted from a decrease in natural mortality, but the spread to higher altitudes appeared to be due to lower mortality associated with warmer and drier years. The phenology of the insect and the effect of the annual harvesting cycle on phenology are discussed.
The responses of Glossina pallidipes Austen (Diptera: Glossinidae) to odourbaited traps and targets in Somalia
Authors: Torr S. J , Parker A. G , Leigh-Browne G
Published: July 2009

Studies were carried out at Jilaal Moogi, south-eastern Somalia, of the responses of Glossina pallidipes Austen to traps and targets. F3 traps caught three times as many tsetse as a biconical trap. Baiting F3 traps with acetone (released at 5–50 000 mg/h), butanone (10–50 mg/h) or octenol (0·05–5 mg/h) either alone or as mixtures did not affect the catch significantly. The catch was increased by 1·6 times (P<0·05) by releasing a mixture of 4–methylphenol (at 0–2 mg/h) and 3-n-propylphenol (0·04 mg/h), and by four times by releasing a mixture of acetone (500 mg/h), octenol (0·5 mg/h) and the two phenols. Baiting a target enclosed in an electric net with the combination of acetone, octenol and phenols increased the catch only 1·3 times, (P>0.05). Baiting an electric net plus target with natural ox odour increased the catch 1·8 times (P<0·05). A pthalogen blue (peak reflectivity = 40% at 450 nm) target caught 1·7 times as many tsetse as a black target (P<0·01) and a standard blue (reflectivity = 29%) target caught 7·4 times the catch of a yellow one (P<0·001). The results are compared with published data from Zimbabwe, Kenya and Mozambique, and it is noted that the level of response of G. pallidipes in Somalia to host odours is lower than elsewhere.
Tethered flight ofChilo partellus(Swinhoe) (Lepidoptera: Pyralidae)
Authors: Päts Peeter , Wiktelius Staffan
Published: July 2009

Static tethered flight was used under laboratory conditions to investigate the flight duration ofChilo partellus(Swinhoe). A flight mill was used to measure flight velocity. Mated females flew for a longer time than unmated ones. Females also flew for a longer time than males. Mated females were able to fly and lay eggs alternately for at least three nights in a row. Flight did not affect the number of eggs deposited by females. The results from the flight mill show that the mill is an accurate device to measure flight velocity. The airspeed ofC. partellusproved to be 0.9 m/s, and there appeared to be no difference between the flight velocity of mated or unmated males and females.
The effects of intercropping and mixed varieties of predators and parasitoids of cassava whiteflies (Hemiptera: Aleyrodidae) in Colombia
Authors: Gold Clifford S. , Altieri Miguel A. , Bellotti Anthony C.
Published: July 2009

Cassava intercropped with cowpea in Colombia had lower numbers of Aleurotrachelus socialis Bondar and Trialeurodes variabilis (Quaintance) per leaf and per plant than did monoculture cassava. These differences persisted for up to six months after harvest of the cowpea. These results are examined in light of the natural enemies hypothesis, which suggests that natural enemies may be favoured in diversified systems, thereby reducting herbivore load. In this regard, the effects of different cropping systems on the whitefly predator Delphastus pusillus (Le Conte) and on the combined action of the parasitoids Amitus aleurodinus Haldeman and Eretmocerus aleyrodiphaga (Risbec) are discussed. D. pusillus displayed a functional responce and was more abundant in monocultures than in intercrops. Predator:prey ratios were similar between treatments and so low that predation appeared to have little impact on whitefly numbers. Parasitism levels of Aleurotrachelus socialis were not affected by crop combinations. The data suggest that the activity of the natural enemies does not explain cropping system effects on cassava whitefly populations.
Temporal and spatial patterns in pheromone-trap catches of Helicoverpa spp. (Lepidoptera: Noctuidae) in cotton-growing areas of Australia
Authors: Fitt G. P. , Zalucki M. P. , Twine P.
Published: July 2009

Helicoverpa armigera (Hübner) and H. punctigera (Wallengren) are major pests of cotton and other field crops in Australia. Using data on then abundance of males in pheromone traps at many sites over three seasons, the spatial and temporal variation in trap catch of both species were examined using Taylor's power law and spatial autocorrelation. The distribution of both species was highly clumped, both temporally and spatially. Regression Coefficients for the relationship of spatial mean to variance (bs) were similar to those for noctuids in general, while similarly derived temporal values (bt) for H. armigera fell towards the upper end of the noctuid range and those for H. punctigera well above the range given by Taylor & Woiwood (1980). Taylor and colleagues suggested that patterns of dispersion are species-specific and that they reflect density-dependent patterns of movement towards and away from centres of abundance. Although the relationship between variance and mean abundance for both spatial and temporal aspects of trap catches of Helicoverpa is well fitted by Taylor's power law, it is argued that these patterns of dispersion are a consequence of demographic and environmental stochasticity. Little need is to invoke specific density-dependent behaviours as the major factor responsible in this case. In addition, while Taylor's power law indicated both species had a similar clumped distribution, limited autocorrelation analysis suggested a random dispersion of pheromone-trap catches for H. armigera and small scale patchiness (over distances of 1–2 km) in trap catches of H. punctigera.
A key for the identification of Afrotropical species of the shoot-fly subgenus Atherigona of Atherigona (Diptera: Muscidae), with a description of some new species from Africa
Authors: Dike M. C.
Published: July 2009

A key for the identification of males of all Afrotropical species of the subgenus Atherigona of Atherigona described to date is presented. Four new species, A. alaotrana sp. n. from Madagascar, A. bowdeni sp. n. from Uganda, A. dentifolia sp. n. from Kenya and A. palpalis sp. n. from Nigeria, are described.
The influence of drought stress on the distribution of insects on four groundnut genotypes grown near Hyderabad, India
Authors: Wheatley A. R. D. , Wightman J. A. , Williams J. H. , Wheatley S. J.
Published: July 2009

Four groundnut genotypes were grown in a randomized block design across a drought-stress gradient to determine the influence of this factor on insect distribution in the 1985–86 post-rainly season near Hyderabad, in peninsular India. The leaf-miner Aproaerema modicella (Deventer) was most abundant on the most stressed plants. The cicadellid Empoasca kerri Pruthi had the reverse distribution. The thrips Frankliniella schultzei (Trybom) and Scirtothrips dorsalis Hood were at first densest where drought stress was least. Their distribution subsequently became reversed and, as the condition of their hosts worsened, they again became most abundant at the wetter end of the gradient. Bud necrosis disease caused most mortality where drought stress was highest. A subsidiary experiment indicated that the intensity of overhead irrigation did not influence the density of A. modicella. There were marked genotype effects: JL 24 carried the highest density of insects and was most susceptible to bud necrosis disease: NC Ac 343 had the lowest leaf-miner and cicadellid populations. M 13 and ICGS 11 had intermediate characteristics.
Impact assessment of the biological control of the cassava mealybug,Phenacoccus manihotiMatile-Ferrero (Hemiptera: Pseudococcidae), by the introduced parasitoidEpidinocarsis lopezi(De Santis) (Hymenoptera: Encyrtidae)
Authors: Neuenschwander P. , Hammond W. N. O , Gutierrez A. P. , Cudjoe A. R. , Adjakloe R. , Baumgärtner J. U. , Regev U.
Published: July 2009

The impact ofPhenacoccus manihotiMatile-Ferrero on growth and tuber yield of cassava, and the results of its biological control by the exotic parasitoidEpidinocarsis lopezi(De Santis) were investigated in a survey of 60 farmers' fields in Ghana and Ivory Coast over an area of 180 000 km2of the savana and forest ecosystems. Twenty-nine variables associated with plant growth, agronomic and environmental factors, and insect populations were recorded. Densities ofP. manihotiwere closely correlated with stunting of the cassava shoot tips and, less so, with the rate of stunting early in the growing season. With increasing mealybug infestations, average harvest indices declined and populations ofE. lopeziand of indigenous coccinellids increased, but parasitoids were found at lower host levels than were predators. The length of timeE. lopezihad been present in an area was the most important factor influencing mealybug densities. Thus,P. manihotipopulations were significantly lower whereE. lopezihad been present for more than half the planting season than in areas whereE. lopeziwas lacking or had been only recently introduced. A significant proportion of the farmers in the savanna zone, whereP. manihotipopulations were much higher than in the forest zone, had observed this decline due toE. lopezi. Tuber yield losses due toP. manihotiin the absence ofE. lopeziwere tentatively estimated at 463 g/plant in the savanna zone. No significant effect was found in the forest region. WhenE. lopeziwas present, averageP. manihotidamage scores were reduced significantly, both in the savanna and forest regions. The increase in yields was 228g/plant or about 2.48 t/ha in the savanna region.
The life-history and host specificity ofComostolopsis germanaProut (Lepidoptera: Geometridae), a biological control agent ofChrysanthemoides monilifera(Compositae)
Authors: Adair R. J. , Scott J. K.
Published: July 2009

Larvae of the southern African geometrid mothComostolopsis germanaProut feed on the shoot apices and axillary buds ofChrysanthemoides monilifera, a serious alien weed of native vegetation in Australia. The insect was found in low abundance throughout the distribution of its hosts,C. incanaandC. monilifera, in southern Africa. Larvae were present throughout the year in subtropical Natal, but were absent in winter in the cooler, Mediterranean type climate of Cape Province. In host-specificity tests using 65 plant species from 26 families,Comostolopsis germanacompleted development only onChrysanthemoides monilifera moniliferaandC. monilifera rotundata. Insignificant, exploratory feeding occurred onOlearia axillaris(Compositae) and pea,Pisum sativum(Leguminosae). In multiple-choice oviposition tests eggs were laid on 41 species, but a strong preference was shown for the foliage and stems ofC. monilifera. Larvae grazing the flower buds, pedicels and peduncles ofC. moniliferamay reduce the reproductive capacity of their host and contribute to its control.Comostolopsis germanahas been approved for release as a biological control agent ofChrysanthemoides moniliferain Australia.
Temephos resistance in Simulium damnosum Theobald (Diptera: Simuliidae): a comparative study between larvae and adults of the forest and savanna strains of this species complex
Authors: Hemingway J. , Callaghan A. , Kurtak D. C.
Published: July 2009

Temephos resistance in savanna cytospecies of Simulium damnosum Theobald s.l. and the forest cytospecies S. sanctipauli Vajime & Dunbar, from West Africa is correlated with an increase in general esterase activity. Metabolism studies indicated that esterase products were the major metabolities in both forest and savanna resistant strains of S. damnosum s.l. compared to the susceptibles. In the presence of an esterase synergist, a large amount of the oxon analogue of temephos was produced by the resistant forest cytospecies S. sanctipauli. This strain is also resistant to chlorphoxim, and it is likely that the increase in oxidative activity observed is connected with the chlorphoxim rather than the temephos resistance. There was no evidence of glutathione transferase-, oxidase- or acetylcholinesterase-based temephos resistance machanisms in the savanna species of S. damnosum s.l.
The control of Rastrococcus invadens Williams (Hemiptera: Pseudococcidae) in Togo by the introduction of Gyranusoidea tebygi Noyes (Hymenoptera: Encyrtidae)
Authors: Agricola U. , Agounké D. , Fischer H. U. , Moore D.
Published: July 2009

Rastrococcus invadens Williams was first noticed in Togo in 1981 and has since become a serious pest on many plants, especially mango and citrus. In June 1986, a programme for its biological control was begun, resulting in the introduction into Togo in October 1987 of an encyrtid parasitoid, Gyranusoidea tebygi Noyes. The parasitoid was reared under a simple system and releases were made from November 1987. The parasitoid established readily under a range of ecological conditions and produced significant control within the first year up to 100 km from each release point.
The behaviour of Triatominae (Hemiptera: Reduviidae): a review
Authors: Schofield C. J.
Published: July 2009

Five aspects of the behaviour of the Triatominae are reviewed: hostfinding, defence from predators, habitat selection, activity patterns and substrate preferences, and mating and oviposition behaviour. It is emphasised that knowledge of behaviour is largely restricted to the three speciesTriatoma infestans(Klug),Rhodnius prolixusStål andPanstrongylus megistus(Burm.) and that the behaviour of other species, particularly those with predominantly sylvatic habits, may be quite different in some respects.
Prostaglandins in the salivary glands and reproductive organs of Hyalomma anatolicum excavatum Koch (Acari: Ixodidae)
Authors: Shemesh M , Hadani A , Shklar Ania , Shore L. S. , Meleguir F
Published: July 2009

Prostaglandin F (PGF) and E2 (PGE2) were assayed in the reproductive organs, salivary glands and egg-batches of laboratory-bred males and females of Hyalomma anatolicum excavatum Koch. Salivary glands and reproductive organs were dissected from unfed male and female ticks as well as from ticks that had fed for six days on rabbits; these organs were cultured for 24 and 72 h in tissue culture medium-199 with Earle's salt and HEPES buffer at pH 7·6 and 37°C. The amounts of PGF and PGE2 accumulated in the culture were determined by a radioimmunoassay using specific antibodies. Both salivary glands and reproductive organs were shown to synthesise PGEa and PGF. This synthesis and also the prostaglandin content of the organs were significantly increased after engorgement. The synthesising capacity and content of PGE2 and PGF in both the salivary glands and reproductive organs were higher in the female than in the male.