bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tick infestation patterns in the southern province of Zambia
Authors: MacLeod John 
Published: July 2009

The species-patterns and incidence level of ticks on the larger wild animals and on rodents were examined between 1966 and 1969 in the Southern Province, Zambia. The rodents, except for the elephant shrew, porcupine, and hare, were infrequently infested. The antelopes, except for the eland, had a mean infestation of under nine per individual, the buffalo, zebra, suids and the eland over 20. Twenty species of ticks were found on these hosts. On the ruminants Hyalomma rufipes Koch was absent, and H. truncatum Koch was the most frequent; Rhipicephalus simus Koch, R. tricuspis Dön. and R. pravus group were common. Boophilus decoloratus (Koch) was rare, R. evertsi Neum. infrequent except on zebra and lechwe, and R. appendiculatus Neum occurred on only four of the 15 ruminant species examined. Except on the elephant, Amblyomma was represented solely by A. pomposum Dön.Periodic deticking of cattle, sheep and goats yielded precise quantitative information on the seasonal changes in incidence and species-patterns of ticks. Eighteen species were found on the domestic herbivores. On cattle B. decoloratus was usually numerous and often dominant, except where controlled by dipping or spraying. Compared with infestations on wild animals, H. rufipes was frequent, A. pomposum was replaced by A. variegatum (F.), and R. evertsi and R. appendiculatus were numerous; R. simus, R. tricuspis and the R. pravus group were usually in relatively low numbers.The proportions of the different species on cattle varied widely between the stations and at different seasons. Intensive stocking, with resultant grazing down of the fieldlayer, increased the R. evertsi numbers markedly throughout the year, and depressed the numbers of Hyalomma sp., A. variegatum and of the less common Rhipicephalids during the dry season; except for A. variegatum, their numbers and those of R. appendiculatus rose, however, during the wet season to higher levels than on the less intensively stocked paddocks. Some evidence is presented that Barotse cattle are more heavily infested than Sindhi and Boran cattle.
Recent developments in the ecology and methods of control of tsetse flies (Glossina spp.) (Dipt., Glossinidae)—a review
Authors: Jordan A. M. 
Published: July 2009

AbstractThe literature published during 1964–72 concerned with the ecology and control of Glossina is reviewed and put into context with previously published information. Thirty species or subspecies of Glossina are recognised. Improved methods of sampling have been developed which catch many more females of the morsitans group than other methods and allow more accurate estimates of population density and structure to be made than has been possible hitherto. New concepts of the activity and behaviour patterns of G. morsitans Westwood have been developed from work carried out both in the field and in the laboratory. Detailed studies on resting sites have been followed by successful control campaigns based on the selective use of insecticides. Most large-scale control campaigns during the period under review were based on applications of insecticides from the ground; other control methods used were aerial applications of insecticides, mechanical clearing of vegetation, selective game destruction and a small-scale project using the sterile insect release method. Techniques for identifying and assessing trypanosome infections in Glossina are described and a Table is given of infection rates in various species of tsetse. Differences in observed infection rates can result according to the time and method of sampling but actual infection rates are affected by a variety of factors including the maintenance temperature of puparia and adults, the age of the fly at the time of the infective feed, the age structure of the tsetse population and the hosts on which it feeds. Genetic differences in infectibility may occur between different individuals of a single species and certainly occur between different species.
Effect of temperature on the cereal aphids Metopolophium dirhodum (Wlk.), Rhopalosiphum padi (L.) and Macrosiphum avenue (F.) (Hem., Aphididae)
Authors: Dean G. J. 
Published: July 2009

AbstractThe effect of temperature within the range 10–30°C on Metopolophium dirhodum (Wlk.), Rhopalosiphum padi (L.) and Macrosiphum avenae (F.) was measured in controlled environment cabinets. Development rates increased with temperature to a maximum at 20°C for Metopolophium dirhodum, 22·5°C for Macrosiphum avenae and 25°C for R. padi, decreasing thereafter to zero by 30°C when all the nymphs died. The fourth instar and pre-reproductive adult appeared to be affected at temperatures below those for the younger instars. Mortalities of immature M. avenae were similar between 10° and 25°C, but more immature Metopolophium dirhodum died at high, and R. padi at low, temperatures. Survival rates decreased with increase of temperature, and fecundity was largest at 20°C. Rates of increase became largest at 20°C for M. dirhodum and Macrosiphum avenae and at 25°C for R. padi. Above 15°C, R. padi had a 4–16 times larger capacity for increase than the other two species because it developed faster and achieved its rate of maximum fecundity sooner.
A new procedure and counting instrument for acaricide tests
Authors: Bonin W. , Hilgner W. 
Published: July 2009

AbstractAfter exposure for 24 h in polypropylene envelopes impregnated with the test substance, larvae of Boophilus microplus (Can.) are placed on a hot-plate (40°C) under light to stimulate movement among the survivors. The larvae are drawn one at a time into a suction bottle through a metal capillary into which is built a photo-electric cell that is actuated by each larva as it passes through. The electric impulses are transmitted to a counting device and recorded.
The Solana-group of Empoasca Walsh (Homoptera, Cicadelloidea): its generic status and a new species from pawpaw
Authors: Ghauri M. S. K. 
Published: July 2009

AbstractLeafhoppers collected from dying pawpaw trees in Dominica are described as new under the name Solanasca dominica. This genus is created for the solana group of Empoasca Walsh which is characterised by the shape of the aedeagus; a key is given to the 26 species now known.
The bionomics of Entypotrachelus meyeri meyeri Kolbe and E. m. micans Hust. (Col., Curculionidae) on Tea in East Africa
Authors: Benjamin D. M. , Demba W. M. 
Published: July 2009

AbstractAdults of two subspecies of Entypotrachelus meyeri Kolbe defoliate tea established on land cleared of montane rain forest, E. m. meyeri Kolbe occuring in Kenya and Tanzania to the west of the Great Rift Valley and E. m. micans Hust. only in the foothills of Mt. Kenya east of the Rift. Both subspecies are polyphagous and the host-plants are listed. Oviposition by E. m. meyeri occurs throughout the year; eggs hatch in 10–29 days, and the larvae feed on the roots of tea and various woody plants. The adults cannot fly, but field observations showed they could disperse 2–23 m in 14 days; mark-recapture data showed that 50% of the females lived 32 days, and males 37 days. The bionomics of E. m. micans were similar, but adults lived longer (50% of the females lived 55 days, males 49 days). The leaf area consumed by adults of E. m. micans was 66 mm2/day whereas the total leaf area of a seedling is 30–50 cm2, and it is shown that three adults per plant could effect defoliation in 21 days, assuming no new leaves are formed; leaf destruction at this rate is not considered economically important. Larvae of E. m. micans caused 37% rejection of tea seedlings through destruction of the tap root.
Laboratory investigations to evaluate the possible use of brood Pheromones of the leaf-cutting ant Atta cephalotes (L.) (Formicidae, Attini) as a component in an attractive bait
Authors: Robinson S. W. , Cherrett J. M. 
Published: July 2009

AbstractIn experiments with laboratory-maintained colonies of Atta cephalotes (L.) the responses of foraging workers to brood and brood extracts encountered outside the nest were assessed. Ants returned many of the brood to the nest from about one metre, but few from eight metres; any not returned were dumped over the edge of the foraging table. Living and dead pupae were not distinguished by the ants, but to some extent living and dead larvae were. There was some evidence that brood from their own and from other nests were also distinguished. Attempts were made to simulate brood, using extracts and homogenates on filter paper discs, but in no case did the responses suggest that brood pheromones could be used as arrestants in leaf-cutting ant baits.
Bivoltinism, survival rates and reproductive characteristics of the Scottish biting midge, Culicoides impunctatus (Diptera: Ceratopogonidae) in Scotland
Authors: Blackwell A. , Mordue (Luntz) A.J. , Young M.R. , Mordue W. 
Published: July 2009

AbstractStudies on Culicoides spp. biting midges in south-west Scotland in 1991 revealed that Culicoides impunctatus Goetghebuer, the dominant species throughout the season (May-September), was bivoltine, with a generation period of six weeks. Unseasonal climatic conditions during much of June resulted in a low proportion of first generation females surviving to the parous stage and a reduction in the overall, expected size of the second generation. Distinct behavioural phases of the female midges, such as resting, dispersal and host-seeking, were shown to be directly related to parity states (determined by fat body condition and ovarian development) during the gonotrophic cycle. Female flight activity increased after laying the first, autogenous egg batch, whereas males never flew far from the emergence site. The mean parous rate formula was used to calculate the survival rate of second generation nulliparous females, which was 0.57 per gonotrophic cycle.
Developmental studies on Anagyrus mangicola (Hymenoptera: Encyrtidae), a parasitoid of the mealybug Rastrococcus invadens (Homoptera: Pseudococcidae)
Authors: Cross A.E. , Moore D. 
Published: July 2009

AbstractAnagyrus mangicola Noyes, a primary parasitoid of the mealybug Rastrococcus invadens Williams, a pest of fruit crops in West Africa, was studied under controlled conditions at 27°C and 75% r.h. Data are given on the larval stages, their morphology and duration of immature development. The sex ratios of emerging parasitoids, adult longevity, host stage preference, the relationship of the size of the emerging parasitoid to host stage and development time are also investigated.
Activity rhythms of tsetse flies (Glossina spp.) (Diptera: Glossinidae) at low and high temperatures in nature
Authors: Hargrove J.W. , Brady John 
Published: July 2009

AbstractGlossina morsitans morsitans Westwood and G. pallidipes Austen were caught hourly on electric nets from dawn to dusk in the Zambesi Valley, Zimbabwe, in cold and hot weather. When middle of the day temperatures reached only 24°C, activity of G. morsitans was at a low level from dawn to early afternoon but then rose to a dusk peak (most marked in males); G. pallidipes behaved similarly, but showed almost no activity before noon. When dawn temperatures rose above ca. 24°C (and afternoon temperatures above 38°C) the evening peak disappeared, to be replaced by a peak at dawn (and with almost no activity occurring through the rest of the day). This reversal of the more usual field activity pattern of late afternoon maxima reveals that the positive correlation between activity level and temperature at dusk (Brady & Crump, 1978) breaks down above ca. 33°C, although the earlier conclusion that the typical U-shaped activity pattern of tsetse flies is mainly driven by endogenous timing is still valid for moderate temperatures.
Prey choice and substitution in Chilocorus spp. (Coleoptera: Coccinellidae)
Authors: Hattingh Vaughan , Samways Michael J. 
Published: July 2009

AbstractChoice between prey species by Chilocorus nigritus (Fabricius) and C. bipustulatus (Linnaeus) adults and larvae was determined. Strong preferences were absent and differences in the predators' feeding histories, were not reflected in their choices. The deleterious effects of a prey substitution, during larval development and adult maintenance, were investigated using C. nigritus with supplementary work on C. bipustulatus. These diet changes significantly retarded larval development rate, and subsequent adults were smaller than control individuals. Prey substitutions in the adult diet, suppressed oviposition for several days and feeding rate was reduced at one day after substitution. Larvae were more sensitive than adults to such diet changes. This was not a case of classical unsuitability of the new prey, as the fecundity and feeding rate returned to the same levels as before the substitution after a few days of exposure to the new prey. Furthermore, both prey types were suitable for larval development of C. nigritus when they fed on one exclusively, but unsuitable when substitutions were made. The effects of prey substitutions may possibly be attributed to the presence, in the new prey, of plant toxins, which the predators are initially not physiologically capable of dealing with in large quantities. These results present difficulties for the concepts of monophagy and polyphagy, being less well defined than normally thought. In view of coc-cinellid foraging behaviour and larval habitat selection by adults, the temporary reduction in fitness following a diet change is considered to be adaptive.
Effects of temperature and photoperiod on development and pre-reproductive period of the silver Y mothAutographa gamma(Lepidoptera: Noctuidae)
Authors: Hill J.K. , Gatehouse A.G. 
Published: July 2009

AbstractAdults ofAutographa gamma(Linnaeus) make regular, seasonal migrations into areas where they are unable to breed continuously. Individuals migrate into Britain each spring, and after one, two or three generations, offspring of the spring migrants return to over-wintering areas in North Africa and the Middle East. The larvae are highly polyphagous and have been recorded damaging many crops, especiallyBrassicaspp. Insects usually migrate during the adults' pre-reproductive period (PRP). The length of this period is therefore an index of migratory potential since individuals with longer PRPs have more time to express their capacity for flight and to travel further. Individuals reared outside in Britain in autumn have longer PRPs than individuals reared outside in summer. Laboratory experiments show that PRPs are extended at low temperatures and under short photoperiods and there is some evidence that PRPs are also extended under gradually decreasing photoperiods. By extending PRPs in response to environmental conditions typical of Britain in autumn, individuals are able to increase their potential for pre-reproductive migratory flight and therefore their potential for reaching suitable overwintering sites further south.
Oviposition patterns and the supplementary role of a seed-feeding weevil, Rhyssomatus marginatus (Coleoptera: Curculionidae), in the biological control of a perennial leguminous weed, Sesbania punicea
Authors: Hoffmann J.H. , Moran V.C. 
Published: July 2009

AbstractA seed-feeding curculionid, Rhyssomatus marginatus Fåhraeus, was introduced into South Africa for biological control of a perennial leguminous weed, Sesbania punicea, from South America. R. marginatus has become established even though its larval food source, seeds in ripening pods, is severely depleted by another biological control agent, an apionid, Trichapion lativentre (Beguin Billecocq), which destroys nearly all the flower-buds produced by the plants and reduces seed-set by 98% on average. In spite of this indirect competition, R. marginatus destroys up to 88% of the remaining seeds that develop on S. punicea, regardless of host plant location. Detrimental intraspecific interactions between larvae of R. marginatus are minimized, and the utilization of a depleted food source is optimized, through meticulous selection of oviposition sites by the female weevils. Although numerically inferior, R. marginatus is an important supplementary agent to T. lativentre and together the two species of weevils have almost arrested the reproductive potential of S. punicea.
Trypanosome infection rates in tsetse flies (Diptera: Glossinidae) and cattle during tsetse control operations in the Kagera River region of Rwanda
Authors: Mihok Steve , Otieno Leonard H. , Tarimo Christopher S. 
Published: July 2009

AbstractTrypanosome infections were monitored in three species of tsetse fly (Glossina pallidipes Austen, G. morsitans centralis Machado, and G. brevipalpis News-tead) at four locations in the Kagera River region of Rwanda from May 1989 to September 1990. Two of the four areas (Mpanga Ranch and Bukora Ranch) were subjected to tsetse fly suppression operations with odour-baited traps. Proboscis infections of the Trypanosoma congolense and T. vivax types accounted for roughly equal numbers of the 207 mature infections detected (3.8%). Variation in infection rates was area-specific rather than tsetse species-specific. Order of magnitude differences in tsetse fly densities among areas were not correlated with differences in infection rates at the start of tsetse fly suppression operations. Similarly, declines in population density on both control and experimental areas were not associated with significant changes in infection rates. The prevalence of trypanosomiasis in cattle at Bukora Ranch was not affected by a roughly 90% reduction in Glossina densities. T. congolense accounted for 79% of the infections at an overall prevalence rate of 5.5%. Trypanosomiasis in cattle persisted at extremely low densities of about 0.1 fly/trap/day. Treatment of cattle with diminazene aceturate (BereniR) suggested that many T. congolense parasites were drug resistant, and hence, were cycling among cattle due to the few Glossina present.
Variation between biotype E clones ofSchizaphis graminum(Homoptera: Aphididae)
Authors: Shufran Kevin A. , Margolies David C. , Black William C. 
Published: July 2009

AbstractPhenotypic and genotypic variation was investigated between biotype E clones of the greenbug,Schizaphis graminum(Rondani).S. graminumwas collected from wheat and sorghum fields in seven Kansas counties, USA. Colonies representing single maternal lineages (clones) were initiated and maintained in an insectary, and were verified as biotype E. An allozyme survey among clones did not detect any polymorphism at 24 enzymatic loci. We were unable to detect interclonal variation for nymphal survivorship, age at first reproduction, fecundity, and reproductive lifespan. Variation among genetically homogeneous daughters within clones was as great as variation among different clones for the above parameters, due to microenvironmental effects. However, by using the intergenic spacer in the rDNA cistron as a molecular fingerprinting tool, we identified 56 unique maternal lineages among 61 clones tested. The length of the intergenic spacer varied within individualS. graminum, and different maternal lineages had unique sets of spacer sizes. However,S. graminumwithin a single clone shared the same sets of spacer sizes. Extensive molecular genetic variation was found among biotype E clones, despite a lack of variation in additive genetic traits. Thus, biotype E populations are made up of many genetically distinct clones and do not represent an asexual proliferation of one or a few maternal lineages.
Odour-baited targets to control New World screwworm, Cochliomyia hominivorax (Diptera: Calliphoridae): a preliminary study
Authors: Torr Stephen J. , Hall Martin J.R. 
Published: July 2009

AbstractBiconical, F3, and wind oriented (WOT) traps, and black cloth targets, baited with the odour attractant swormlure-4, were assessed as catching and killing devices for the New World screwworm fly, Cochliomyia hominivorax (Coquerel), in Mexico. Among the traps, the WOT was significantly better than the others, with a mean catch 2.7 and 86.4 times better than those of the biconical and F3, respectively. Release of swormlure-4 could be reduced from the standard 10 ml'day to 2 ml'day without a reduction in the numbers caught in a WOT. Use of electric nets demonstrated that a large visual target was not necessary for the precise location of a swormlure-4 source by C. hominivorax. Target colour was important with respect to the landing response on targets: in a two-choice situation, flies landed much more frequently on black than on blue or yellow, and more on these two colours than they did on white. C. hominivorax tend not to circle a target before landing on it: about 75% of the flies caught on a combination of electrified black target plus electric flanking net were caught on the target. The potential for use of insecticide-impregnated cloth targets in suppression of adult C. hominivorax is discussed.
Survival and infection probabilities of anthropophagic anophelines from an area of high prevalence of Plasmodium falciparum in humans
Authors: Charlwood J.D. , Smith T. , Billingsley P.F. , Takken W. , Lyimo E.O.K. , Meuwissen J.H.E.T. 
Published: July 2009

AbstractDelayed and immediate oocyst rates; parous rates and sporozoite rates were obtained in Anopheles gambiae Giles, A. arabiensis Patten and A. funestus Giles from two villages in the Kilombero Valley, southern Tanzania during the wet season of 1991. Collection methods included light trap, indoor resting collection and nets with holes cut in their side. Mosquito survival estimates from parous rates obtained from light trap collections, were compared with estimates from capture–recapture experiments and from that obtained during a population decline. Methods of estimating the proportion of feeds infectious to mosquitoes, K, were also compared. This proportion varied between villages and species and was highest in the village with the greatest proportion of A. gambiae. We propose that absolute estimates of K should be obtained by determining the immediate oocyst rate and measuring the parous rate using the same host seeking mosquitoes. This estimate was only available from one village and ranged from 1.9% for A. gambiae s.l. to 3.4% for A. funestus.
The effect of bednets on unprotected people: open-air studies in an Afghan refugee village
Authors: Hewitt S. , Ford E. , Urhaman H. , Muhammad N. , Rowland M. 
Published: July 2009

AbstractThe possibility that mosquitoes are diverted from protected people sleeping outdoors in a bednet to an unprotected person immediately adjacent was investigated during field trials conducted in an Afghan refugee village. The presence of an untreated bednet covering three people sleeping adjacent to the subject did not cause a significant rise in the biting rate on that subject. At the dose rates studied, biting rates in the presence of an ImperatorR treated bednet fell slightly (although not significantly). K-OthrineR treated bednets had no discernible effect on biting rates. Similar studies conducted within giant net traps showed that the ImperatorR treated bednet, and to a lesser extent the K-OthrineR treated bednet, did repel mosquitoes. Within these net traps, biting on the unprotected subject decreased considerably in the presence of the imperatorR treated bednets (P < 0.05 for both culicines and Anopheles stephensi Liston in the presence of the ImperatorR treated bednet). The net traps held in volatile components from the treated bednets in much the same way as the walls of a well ventilated room. We conclude that while sleeping next to a treated bednet may be of considerable benefit inside, where one sleeps in relation to a bednet outside is of little importance. Further studies revealed that for each mosquito species, insecticide induced mortality was highest when the bednet contained the preferred host of that species. This suggests that selection for pyrethroid resistance by bednets may be relatively slow to develop in areas where the primary vectors of malaria are zoophilic.