bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incidence of yellows in sugar beet as affected by variation in plant density and arrangement
Authors: Johnstone G. R. , Koen T. B. , Conley H. L. 
Published: July 2009

AbstractAphid species found infesting sugar-beet in Tasmania were Aphis craccivora Koch, Aulacorthum solani (Kalt), Macrosiphum euphorbiae (Thos.) and Myzus persicae (Sulz.). The activity of infective alatae over plots of sugar-beet established by sowing at different densities and arrangements to produce 12 treatments was gauged by recording the numbers of plants which became affected with virus yellows symptoms. The incidence of yellows increased as plant density decreased and as plant arrangement altered from rectangular to more square patterns. A regression equation of the form: where a, b, c and d were constants and x and y the intra- and interrow spacings, respectively, accounted for 92% of the variation produced by the 12 treatments. These results indicate that the incidence of virus infection in row crops resulting from aphid flight activity may be manipulated through altering plant density and arrangement.
Studies on the flight of black-flies (Diptera: Simuliidae). I. Flight performance ofSimulium ornatumMeigen
Authors: Cooter R. J. 
Published: July 2009

AbstractThe flight performance ofSimulium ornatumMg. s.l. was measured under laboratory conditions using a simple flight mill. Males and unmated females were flown and the duration, distance and average speed of flight were recorded for adults fed on water only, sucrose, blood & water, or blood & sucrose. On 91% of all test occasions sucrose-fed insects flew but 25% of those on water only did not fly. Feeding flies on 10% sucrose solution markedly improved both willingness to fly and flight performance, and under these conditions maximum duration, distance and average speed recorded were 4.9 h, 4·2 km and 2·84 km/h, respectively. The ratio of average to maximum speed was 0·631 for females and 0·610 for males, with absolute maximum speeds of 3·19 and 2·99 km/h, respectively. Duration and distance flown were well-correlated, speed being the least variable aspect of flight performance measured. The distributions of flight duration and distance flown were skewed such that few insects made long flights. Mean flight performance at different ages was measured; unmated females appeared to retain a high level of willingness to fly throughout the age-range tested (up to 33 days). The longest recorded flight (5·3 h) was made by a female during an overnight experiment. The implications for long-range flight movements by simuliids are discussed.
The development of resistance to certain organophosphorus and carbamate ixodicides by the blue tick, Boophilus decoloratus (Koch) (Acarina, Ixodidae), in Rhodesia
Authors: Matthewson M. D. , Wilson R. G. , Hammant C. A. 
Published: July 2009

AbstractEight strains of Boophilus decoloratus (Koch) are described from farms in the High veld area of Rhodesia. All eight strains showed resistance to a number of organophosphorus ixodicides and four showed additional resistance to the carbamate, carbaryl. This is the first recorded resistance to these two groups of ixodicides in Rhodesia.Biochemical studies on the Alicedale West Farm strain indicated a level of resistance between that of the Berlin strain of B. decoloratus and the Biarra strain of B. microplus (Can.).
The genetic basis for organophosphorus resistance in the Australian sheep blowfly, Lucilia cuprina (Wiedemann) (Diptera, Calliphoridae)
Authors: Arnold J. T. A. , Whitten M. J. 
Published: July 2009

AbstractOrganophosphate resistance in Lucilia cuprina (Wied.) is shown, by the backcross and discriminating dose technique, to be controlled by two major genetic loci on chromosomes 4 and 6. Respectively designated Rop-1 and Rop-2, they are positioned on the known genetic map. Rop-1 has three resistance alleles and one of these, and the Rop-2 allele, demonstrated stable transmission and expression in the absence of insecticide. Expression of resistance was either intermediate or incompletely dominant depending on locus and stage of maturity. This, and interaction between the loci, suggests that they have different biochemical mechanisms.
Effects of human blood group, sweating and other factors on individual host selection by species A of the Anopheles gambiae complex (Diptera, Culicidae)
Authors: Thornton Christine , Doré Caroline J. , Willson J. O. C. , Hubbard Judith L. 
Published: July 2009

AbstractThe suggestion that mosquitoes can discriminate ABO blood group status in man was re-examined and an attempt made to determine recognition mechanisms.Host choice was assessed in the laboratory by recording landings on and blood-meals taken from the forearms of pairs of human volunteers in a 10-min exposure to 20 females of species A of the Anopheles gambiae complex, and an alternative procedure, which did not involve mosquitoes probing the host's skin, was developed and evaluated. The presence of weals on the host's skin was found to be an unreliable indicator of probing or feeding activity by mosquitoes. The effect of thermally induced sweating was also investigated.No effect of ABO blood group status on host choice was found. Mosquitoes did, however, show a highly significant preference to land and feed on a subject when thermogenic sweating was induced. Secretor substances in the sweat did not influence host selection.The predictive value of host variables such as MN blood group, skin temperature and humidity, skin colour and forearm hair density in determining host choice was examined. Very little of the observed variation in mosquito activity could be accounted for by these host variables within the ranges used.
Biology and ecology of Stomoxys nigra Macquart and Stomoxys calcitrans (L.) (Diptera, Muscidae) in Mauritius
Authors: Kunz S. E. , Monty J. 
Published: July 2009

AbstractThe distribution and seasonal abundance of Stomoxys nigra nigra Macq. and S. calcitrans (L.) in Mauritius was determined by field surveys in 1973–74. S. nigra, the species of major importance, is most common throughout the wetter, higher elevations where it becomes a major pest of cattle. S. calcitrans occurs throughout the island to a much lesser extent. Coastal areas with less than 60 inches of rain are generally free of damaging infestations of both species. Seasonal infestation levels were determined by making counts of flies feeding on animals and of flies on resting surfaces. Populations of up to 200 S. nigra per animal were highest during the warm, wet, sugar-cane cropping season but declined to generally non-damaging levels during the cool season. S. calcitrans increased up to 145 flies/animal during the cool, drier season and virtually disappeared during the wet season. S. nigra accounted for up to 98% of the total Stomoxys infestation with S. calcitrans making up 62 % of the total at one study site during the study.Sugar-cane debris in fields was found to be the primary breeding source for 5. nigra, whereas decaying manure and organic matter provided the source for S. calcitrans. Generation-to-generation increases were usually below five-fold for both species. Both species exhibit two feeding peaks throughout the day at temperatures of 14°C or above.
Descriptions ofTachinobiagen. n. and three new species of Tetrastichinae (Hymenoptera: Eulophidae), with a tentative key to genera
Authors: Bouček Z. 
Published: July 2009

AbstractTachinobiagen. n. is defined andT. repandasp. n. andT. gradwellisp. n., both of which are parasites of Taohinidae, are described and illustrated.Kocourekia clavigerasp. n., a parasite ofMegachile, is also described. A tentative illustrated key to 17 genera of Tetrastichinae is given, with notes on all genera and details of hosts and geographical distribution for included species. One species,Quadrastichodella eucalypti, is probably phytophagous and is widely distributed on cultivated eucalypts.
Development of Gryon gnidus (Nixon) (Hymenoptera: Scelionidae) in eggs of Acanthomia tomentosicollis (Stål) (Hemiptera: Coreidae) killed either by gamma irradiation or by freezing
Authors: Egwuatu R. I. , Ajibola Taylor T. 
Published: July 2009

AbstractThe effects of host quality on the development of Gryon gnidus (Nixon), a scelionid egg-parasite of Acanthomia tomentosicollis (Stål), are reported. A minimum exposure period of 24 h at —4°C or an irradiation dose of 1000 rads from a cobalt-60 source killed 98–99% of freshly-deposited, fertile eggs of A. tomentosicollis. Sub-lethal periods of exposure delayed hatching in both treatments and the incubation period was increased from 4 days to 5–7 days in eggs exposed to freezing temperature and 4–7 days in irradiated eggs. About 44% of the fertile, untreated eggs hatched normally while 56% were parasitised by G. gnidus. The irradiated or frozen eggs did not hatch and were not parasitised by G. gnidus, thus indicating that G. gnidus would not parasitise dead eggs of A. tomentosicollis. The significance of these results is discussed.
Effects of gamma radiation on the stable fly, Stomoxys nigra Macquart (Diptera: Muscidae)
Authors: Ramsamy M 
Published: July 2009

AbstractFreshly formed (less than 1-day-old) pupae of Stomoxys nigra Macq. treated with gamma rays showed a linear-regression mortality-response with radiation exposure. Mature 5-day-old pupae did not show this effect and were considered more suitable for sterility studies. Flies emerging from both groups of treated pupae showed no deviation from a 1:1 sex ratio. Radiation inhibited fecundity. An exposure dose of 1000 R halved egg production and a dose of 2000 R almost stopped oviposition. Females from pupae exposed to 3000 R produced no eggs. Complete sterility of males was not achieved within the range of tested dosage; exposures of 3000 R and 4000 R induced 98–8 and 99–7% male sterility, respectively. Radiation reduced the longevity of both males and females. A dose of 3000 R did not impair either male mating ability or sexual competitiveness in small-scale laboratory tests.
Observations on the biology ofCerambyx duxFaldermann in the Maltese Islands
Authors: Saliba L. J. 
Published: July 2009

AbstractThe distribution and host-range ofCerambyx duxFald. are summarised, and the detailed life-history in Malta, where the hosts are apple and pear, is described. Collections of various stages from host material indicate that the duration of the complete life-cycle is three years, including a 26–28 month larval period. The number of larval instars is estimated at six. Egg survival is dependent on high humidity. The early months of larval activity are confined to the superficial regions of the trunk and main branches of the host, penetration of the sapwood and heartwood occurring later. No special air-holes appear to be constructed by the larva. No exit gallery is constructed, and the emerging adult makes use of the existing burrows, finally gnawing its way to the exterior. The period of emergence is short (8–10 days) and may be stimulated by rain. Adult life lasts about one month. The average number of eggs laid per female is approximately 13. The main predator onC. duxlarvae is the larva ofZeuzera pyrina(L.). This is confined to the lesser limbs of trees in Malta, but extends throughout the trees in Gozo, and has practically eliminatedC. duxfrom this island.
Large-scale rearing of tsetse flies (Glossina spp.) in the absence of a living host
Authors: Mews A. R. , Langley P. A. , Pimley R. W. , FLOOD M. E. T. 
Published: July 2009

AbstractA successful technique for feeding colonies of Glossina morsitans morsitans Westw. and G. austeni Newst. in the absence of living hosts is described. Insects are fed through membranes made of silicone rubber or of agar and Parafilm, overlying blood pools poured onto grooved glass plates. The diet employed is fresh pig blood, collected at slaughter, and aseptic procedures are adopted at every stage of diet preparation and presentation. The reproductive performance of these in vitro-fed colonies in terms of adult survival, fecundity, and offspring size, is the same as that of colonies fed on living hosts, when compared over a long period of time. The fact that the technique is successful when used with a diet of pig blood, but is not successful when used with cow blood prepared in the same way, suggests that the technique per se is adequate to elicit a normal feeding response from these tsetse species. The nature of the nutritional superiority of pig blood is not understood.
Ecological studies of ixodid ticks (Acari: Ixodidae) in Zambia. III. Seasonal activity and attachment sites on cattle, with notes on other hosts
Authors: MacLeod J. , Colbo M. H. , Madbouly M. H. , Mwanaumo B. 
Published: July 2009

AbstractThe seasonal activity of the adults of 13 tick species was studied on cattle herds in the Central Province of Zambia from 1969 to 1972. The six main species, Boophilus decoloratus (Koch), Hyalomma marginatum rufipes Koch, H. truncatum Koch, Amblyomma variegatum (F.), Rhipicephalus appendiculatus Neum., and R. evertsi Neum. behaved as previously described for the Southern Province. R. compositus Neum. appeared from August, with peak numbers in September–October. R. simus Koch and R. tricuspis Dön. appeared from October, for seven months and three months respectively. R. supertritus Neum. and Ixodes cavipalpus Nutt. & Warb. had a brief activity season from November to January, and R. pravus gp. and R. sanguineus gp. were active from December to July. The distribution of ticks over the body of cattle was determined by fractionised collections, which gave reliable quantitative information for nine of the species. A limited number of collections from sheep, goats and dogs are analysed in relation to season. Collections from 127 wild animals, mainly along the escarpment and riverine bush of the Zambesi, are recorded.
Seasonal fluctuations of Culicoides species (Diptera: Ceratopogonidae) in Kenya
Authors: Walker Alan R. 
Published: July 2009

AbstractLight-traps were used to collect adult Culicoides from 61 sites throughout Kenya and to sample long-term population fluctuations at six sites. Activity patterns were recorded with a suction trap and larval habitats were sampled with laboratory emergence traps. Culicoides cornutus De Medllon, C. milnei Aust., C. pallidipennis C, I. & M., C. schultzei (End.) gp. and C. zuluensis De Meillon were found widespread and also concentrated at livestock pens. Their seasonal population fluctuations did not correlate clearly with rainfall but all these species persist throughout the year. The activity of C. pallidipennis and C. schultzei gp. extends over the whole night and is inhibited by winds in excess of 3 m/s and stimulated by high temperatures and relative humidity. Larval habitats were mainly in mud mixed with detritus or dung; larvae of C. pallidipennis and C. schultzei gp. were both found in swamp mud but not in dung pats. The significance of these findings is discussed in relation to the epidemiology of bluetongue virus disease of sheep and ephemeral fever virus disease of cattle.
The influence of climatic factors on catches of the red bollwonn Diparopsis castanea Hampson (Lepidoptera: Noctuidae) in sex pheromone traps
Authors: Marks R. J. 
Published: July 2009

AbstractMales of Diparopsis castanea Hmps. were caught in a water trap baited with sex pheromone sited 2·0 m above ground level in a cotton field in the Lower Shire Valley, Malawi. Analysis of catches for 21 nights between 8.iii.75 and 3.vi.75 showed that optimal catches of males occurred at wind speeds of 1·0−2·5 m s−1. Wind speeds in excess of 3–4 m s−1 depressed activity. Regression analysis revealed an optimal relative humidity for flight of 60−70%. Inclusion of humidity in a multiple regression analysis with wind speed and temperature failed to improve significantly the relationship with catch provided by a model that considered wind speed and temperature only. No simple relationship existed between temperature and moth abundance, and wind speed clearly exerted the greatest independent effect on catch. Male Diparopsis nevertheless exhibited a temperature-related pheromone responsiveness, with peak catches occurring earlier in scotophase during periods of cool weather. Analysis of data gathered during the 1973 and 1974 seasons indicated a slight, but significant, positive correlation between night rainfall and moth catch. However, none of the various independent and joint relationships established between moth catch and climatic factors could be reliably used for forcasting moth abundance.
Studies on the biology and taxonomy of someChilocorusspp. (Coleoptera: Coccinellidae) preying onAulacaspisspp. (Hemiptera: Diaspididae) in East Africa, with the description of a new species
Authors: Greathead D. J. , Pope R. D. 
Published: July 2009

AbstractField studies of predators onAulacaspis tegalensis(Zhnt.) and laboratory breeding experiments, supplemented by taxonomic studies, showed thatChilocorus discoideusCrotch andC. bilineataKorsch. are junior synonyms ofC. schioedteiMuls. and that two other forms, originally described as ‘aberrations’, may also belong to this species. Similarly,C. erythrocephalusMuls. andC. solitusWeise are junior synonyms ofC. distigma(Klug).C. rufoplagiatussp. n., allied toC. distigma, is described from the shores of Lake Victoria, and the Oriental speciesC. nigritus(F.) is recorded from the African mainland for the first time.C. distigmais found in the savanna and steppe areas of Africa andC. schioedteiin the forest and adjoining zones. Comparative studies suggest that, althoughC. schioedteihas a higher fecundity, it is not displaced byC. distigmaas, unlike the latter, it is unable to breed under hot dry conditions. Comparison of host records for these two species show thatC. distigmais not restricted to feeding on Diaspididae, as isC. schioedtei, but that otherwise the range of hosts and associated plants is similar for both species. The potential of these species andC. nigritusfor use in biological control is discussed and it is suggested thatC. schioedteiis only suitable for trial in tropical areas without a dry season, but thatC. distigmaandC. nigritusmay be useful under a wider range of conditions.
A New species of Exaeretopus Newstead (Homoptera: Coccidae) attacking wheat in Iraq
Authors: Williams D. J. 
Published: July 2009

AbstractExaeretopus tritici sp. n. is described and illustrated from specimens collected in the Ninevah and Arbil Provinces of Iraq. In 1975, it was present in considerable numbers on the stems and inner surfaces of the leaves of wheat. Triticum aestivum, and the infestations reduced ear and grain size.
The flight of tsetse flies (Diptera : Glossinidae) to and from a stationary ox
Authors: Vale G. A. 
Published: July 2009

AbstractGlossina morsitans morsitans Westw. and G. pallidipes Aust. flying to and from a stationary ox were captured by a wall of electrocuting netting at distances ranging from 45 m upwind of the ox to 120 m downwind. The pattern of catches at each distance suggested that most flies not recently fed were attracted to the ox from downwind, from distances up to about 90 m. Most flies leaving the ox flew downwind. This was most marked for flies that had fed on the ox, some of which travelled 120 m within about 30 min of engorging.
The immature stages ofElachiptereicus abessynicusBecker andPachylophus lugensLoew (Diptera: Chloropidae)
Authors: Deeming J. C. 
Published: July 2009

AbstractThe larvae and pupae ofElachiptereicus abessynicusBecker and ofPachylophus lugensLw. are described and illustrated and those of the latter species are compared with those ofPachylophus beckeriCurr. A previous misidentification ofP. beckeriis recorded and additional records of host plants and distribution are given for all three species.
Population dynamics of Xyleborus fornicatus Eichhoff (Coleoptera: Scoly-tidae) in relation to yield trends in tea
Authors: Sivapalan P. 
Published: July 2009

AbstractA highly significant negative linear correlation (r=– 0·911, P=0·001) was observed between Xyleborus fornicatus Eichh. population levels in tea plants and the crop size in the preceding month. A highly significant negative linear correlation (r=– 0·858, P=0·001) was also observed between Xyleborus population levels and the percentage of healed galleries of the respective samples. Cambial activity, which has a direct relationship with crop size, determines the rate of healing of brood galleries, and this seems to be the critical factor that regulates population size within a pruning cycle. Since the population has an inverse relationship to crop size and as the latter could be predicted in advance using weather parameters, it should be possible to predict population levels of Xyleborus in advance.
A critical review of procedures for sampling populations of adult mosquitoes
Authors: Service M. W. 
Published: July 2009

AbstractA critical review is presented of the many and varied procedures for sampling adult mosquitoes. All sampling methods are subject to bias, but human-bait collections are probably the most reliable single method for detecting and monitoring populations of anthropophilic species. The estimation of realistic man-biting rates, however, remains difficult. The recent advances in computer technology have generated considerable interest in population modelling, with the aim of getting a better insight into the complexities of population dynamics, mosquito control and disease transmission. Although such approaches may be informative, it is stressed that models should be based on meaningful values of the critical parameters and that these are best obtained from field populations. The difficulties of interpreting mosquito collections in both attractant traps, such as animal-baited traps, carbon-dioxide-baited traps and light-traps, and in non-attractant ones, such as Malaise traps, sticky traps, ramp traps, rotary traps, suction traps and vehicle-mounted traps, are described. Suction traps probably provide the least biased catches of aerial populations of mosquitoes, but, if populations as a whole are to be considered, then resting adults also must be adequately sampled, and this may prove difficult. It is emphasised that different trapping techniques usually sample different components of a population, and that the choice of sampling methods depends much on the type and quality of information required. The limitations of using mark-recapture techniques to study adult dispersal and obtain absolute population estimates are discussed, together with the advantages and disadvantages of applying simple and more complex mathematical procedures for analysing recapture data.
Sensory receptors on the ovipositor of the carrot fly (Psila rosae (F.)) Diptera: Psilidae and the cabbage root fly (Delia brassicae) (Wiedemann) (Diptera: Anthomyiidae)
Authors: Behan Mary , Ryan M. F. 
Published: July 2009

AbstractThe ovipositor of Psila rosae (F.) comprises abdominal segments seven, eight and nine, the latter with well-defined tergite, sternite and anal cerci. Approximately 110 trichoid sensilla are located on the ovipositor. The ovipositor of Delia brassicae (Wied.), comprising abdominal segments six, seven, eight and nine, has a well-defined sternite on segment eight, with a tergite, sternite and cerci on segment nine. Approximately 245 trichoid sensilla are located on the ovipositor, in addition to 20 styloconic-type and four basiconic-type sensilla. These extra sensilla may enhance chemical discrimination, and thus host-finding, by D. brassicae. Transmission electron microscopy was used to reconstruct a trichoid sensillum, probably a mechanoreceptor, on the cerci of D. brassicae.