bluuebunny/crossref_metadata_2025_split huggingface dataset:
Season-long control of yellow stem borer,Scirpophaga incertulas(Lepidoptera: Pyralidae) by mating disruption with the natural ratio of pheromone components
Authors: Cork A , De Souza K , Krishnaiah K , Ashok Reddy A , Zainullabuddin S 
Published: July 2009

AbstractControl of yellow stem borer,Scirpophaga incertulas(Walker), in rice was attempted by mating disruption using the natural ratio of pheromone components, a 1:3 blend of (Z)-9- and (Z)-11-hexadecenal, in replicated trials at three locations in Andhra Pradesh, India, during the 1994 and 1995 dry seasons. The pheromone was formulated in SelibateRand applied by hand at a rate of 40 g a.i./ha. In Medchal and Nellore, pheromone-mediated communication was reduced by at least 94% for the first 50 and 64 days after application respectively, as measured by pheromone trap catch suppression. Compared with adjacent farmers' practice plots, subsequent dead heart and white head damage were reduced by 74 and 63% and 83 and 40% in Medchal and Nellore, respectively. In Medchal, average rice yields were increased compared to the farmers' practice plots, 4108 and 3835 kg/ha respectively, but in Nellore, they were the same as those obtained in the farmers' practice plots, 6400 and 6733 kg/ha respectively. In Warangal, the level of communication disruption over the first 70 nights after pheromone application was less than obtained in either Medchal or Nellore and averaged between 50 and 87%. The maximum dead heart and white head damage recorded in the pheromone-treated plots in Warangal were 2.8 and 15.7% respectively compared to 7.0 and 20.9% respectively in the farmers' practice plots. Differences inS. incertulaslarval damage estimates obtained from the pheromone-treated and farmers' practice plots in Warangal were reflected in grain yields, 4036 and 3715 kg'ha respectively. Surveys of insecticide use indicated that 92% of smallholders in Medchal applied insecticide at least once per season while in Warangal over 60% applied insecticide on two or more occasions. The data show that season-long control ofS. incertulascomparable to that obtained with conventional insecticides can be achieved by mating disruption in smallholder rice fields in India.
Tethered flight and morphometric studies with Cicadulina storeyi and C. mbila leafhoppers (Hemiptera: Cicadellidae) vectors of maize streak virus in Uganda
Authors: Downham M.C.A. , Cooter R.J. 
Published: July 2009

AbstractTethered flight studies, carried out in southern Uganda with the leafhoppers Cicadulina storeyi China and C. mbila Naudé, showed that depending on species, the factors of age, gender, gravid status and rearing on virus infected maize had significant effects on flight, whereas host plant species and mated status appeared unimportant. Distributions of wing length (WL), body length (BL) and the parameters WL/BL and WL-BL were mostly uni-modal, but in two cases very weakly bi-modal. Regressions of log-transformed flight duration against these morphometric parameters were all non-significant, except for very weak (r2 = 0.01–0.04) relations with wing length. There was no conclusive evidence for the existence of separate short- and long-duration flight morphs among the leafhoppers. It is proposed that differences between our results and those of an earlier study of Zimbabwean Cicadulina populations, particularly in respect of the effects of gravid status on flight, and the existence of distinct flight morphs, are explicable in terms of the different seasonal and environmental constraints experienced by Ugandan and Zimbabwean populations. These favour long-range migratory flight at certain times of the year in Zimbabwe, but not in Uganda.
Selection for and against resistance to insecticides in the absence of insecticide: a case study of malathion resistance in the saw-toothed grain beetle,Oryzaephilus surinamensis(Coleoptera: Silvanidae)
Authors: Mason P.L. 
Published: July 2009

AbstractIn the absence of insecticide there may be intense selection against alleles conferring insecticide resistance, so that these alleles will decline in frequency. On the other hand, selection will act to favour alleles at modifier loci which cause resistance alleles to become coadapted and increase in fitness even in the absence of insecticide. The relative effectiveness of these two processes is of practical importance and theoretical interest. The fate of polymorphism for malathion resistance was studied in the saw-toothed grain beetle,Oryzaephilus surinamensis(Linnaeus). Five to six lines of each of four strains (8401, 8401sel, 8518B and L1040), each polymorphic for resistance phenotypes, were maintained in insecticide-free culture for up to nine generations, over which period the response of individuals to a discriminating dose of 65 mg m-2malathion was determined. There was significant reversion to susceptibility in the related strains 8401, 8401se1 and 8518B. Assuming resistance to be primarily controlled by a single major locus, resistant homozygote and heterozygote fitnesses in the absence of insecticide were estimated to be 0.92, 0.83 and 0.68, respectively. The initial frequency of the resistant allele was inversely related to the time since last exposure to insecticide, and also to the fitness of the resistant allele. This could be explained by the selection of modifier alleles that reduce the fitness cost of resistance in the absence of insecticide. In strain L1040 the proportion of resistant individuals actually increased over time (after the second generation) in the absence of insecticide. The fitness of the susceptible allele in this case was 0.83. In all strains there was significant variation among lines in relative fitness and initial resistance allele frequency. Analysis of knockdown proportions revealed highly significant variation between generations that is not easily interpreted in genetic terms but is better explained by limitations of the knockdown bioassay.
Revision of the subgenusCeratitis(Ceratalaspis) Hancock (Diptera: Tephritidae)
Authors: De Meyer M. 
Published: July 2009

AbstractThe fruit fly genusCeratitis(Diptera: Tephritidae) comprises several important pest species attacking a wide range of unrelated fruits. This is the second paper in a series revising this genus, and deals with representatives of the subgenusCeratalaspis. Thirty-six species are recognized, of which five are described as new:C. sucinisp. n.,C. hancockisp. n.,C. neosticticasp. n.,C. paradumetisp. n.andC. mlimaensissp. n.Ceratitis pycnanthi(Ghesquière) is considered to be synonymous withC. striatellaMunro, and the possible synonymies ofC. giffardiBezzi andC. sarcocephali(Bezzi) withC. cosyra(Walker), as well asC. lineata(Hering) withC. striatellaMunro are discussed. Lectotypes are designated for the following species:C. connexa(Bezzi),C. discussaMunro,C. divaricata(Munro),C. dumetiMunro,C. lentigeraMunro,C. lunataMunro,C. marriottiMunro,C. melanopus(Hering),C. parinarii(Hering),C. quinaria(Bezzi),C. scaevolae(Munro), andC. simiMunro. A key is provided, with illustrations of mesonotal and wing patterns and shape of aculeus tip. All species are Afrotropical and most are restricted to the sub-saharan region, except forC. quinariawhich is also known from the Middle East (Yemen). Distribution and known host plant data are given. Tentative species groups within the subgenus are discussed.
Olfactory responses of Glossina fuscipes fuscipes (Diptera: Glossinidae) to the monitor lizard Varanus niloticus niloticus
Authors: Mohamed-Ahmed M.M. 
Published: July 2009

AbstractVisual and olfactory responses of Glossina fuscipes fuscipes Newstead to the monitor lizard, Varanus niloticus niloticus Laurenti were studied using various catching devices near Lake Victoria, Kenya. Electric nets baited with visible lizards caught more males (×2.1) and significantly more females (×2.0) than unbaited nets. Lizards concealed in electrified black PVC pipe models, simulating the shape and size of a monitor lizard, increased significantly the catches of tsetse by 2.1 times. Fresh lizard urine dispensed at an evaporation rate of 500 to 1000 mg/h also increased significantly the catches of flies at biconical traps, electrified models and electric nets. Identification of chemical constituents of the odour could improve monitoring and control strategies for G. f. fuscipes, and possibly for other palpalis tsetse species.
Variation in attack by the mahogany shoot borer, Hypsipyla grandella (Lepidoptera: Pyralidae), in relation to host growth and phenology
Authors: Newton A.C. , Cornelius J.P. , Mesén J.F. , Corea E.A. , Watt A.D. 
Published: July 2009

AbstractIn order to evaluate the relationships between attacks by the mahogany shoot borer Hypsipyla grandella (Zeller) and host growth and phenology, field trials of Spanish cedar Cedrela odorata and American mahogany Swietenia macrophylla established in Costa Rica were assessed intensively over an 84 week period. Height growth of C. odorata was approximately twice that of S. macrophylla, with mean growth rates of 2.0 and 1.3 cm week−1 respectively. Cedrela odorata displayed pronounced temporal variation in leaf phenology, with a minimum of 51% of trees in leaf during a relatively dry period. In contrast, the minimum proportion of foliated S. macrophylla trees was 87%. No shoot borer attacks were recorded on S. macrophylla until week 50 after the onset of assessments, whereas initial attacks of C. odorata were recorded during week 6. By week 84, the proportion of trees attacked was 74% and 77%, respectively. In both species, attacks were concentrated in seasonal peaks, coinciding with the production of new shoots. Pronounced spatial variation in attack was observed in both species. At week 12, the number of attacks per block in C. odorata was negatively correlated with available calcium concentration (r=0.85, P<0.001), whereas mean height growth of C. odorata was positively correlated with available phosphate concentration (r=0.84; P<0.0001). Significant variation in height to first damaging attack was observed in both species. By the end of the observational period, only 6% of C. odorata and 0.4% S. macrophylla remained undamaged to a height of 3 m. It is suggested that control methods for the mahogany shoot borer should take account of temporal dynamics in attack, and relationship to host phenology. Manipulation of the soil nutrient status may also form part of an integrated approach to pest management.
Dispersal and survival of Anopheles funestus and A. gambiae s.l. (Diptera: Culicidae) during the rainy season in southeast Tanzania
Authors: Takken W. , Charlwood J.D. , Billingsley P.F. , Gort G. 
Published: July 2009

AbstractIn a rural area of southeastern Tanzania, studies were undertaken on the dispersal and survival of Anopheles funestus Giles and A. gambiae Giles s.l. during the rainy season. Blood fed, resting mosquitoes were collected indoors, marked with fluorescent powder and released on the same day from two different sites in the study area. For two weeks indoor resting mosquitoes were collected from 11 houses in the release area. Additional collections were made with a light trap from a sentinel house in the centre of the study area. Anopheles funestus was more abundant than A. gambiae s.l. Of 4262 A. funestus and 645 A. gambiae s.l. released, 4.3% and 7.4%, respectively, were recaptured. Dispersal of mosquitoes was not random: one of three areas was favoured significantly more than the other areas, as shown by the recapture and movement rates of marked mosquitoes. Based on the regression of the recapture rate, estimated daily survival rates of A. funestus and A. gambiae s.l. were 0.63 and 0.78, respectively. These were significantly different. The differences in dispersal and survival rates between the two species are discussed in view of local topography and species-specific characteristics.
On a new Species of Ephialtes (Hym., Ichneumonidae) parasitising the Codling Moth
Authors: Perkins J. F. 
Published: July 2009

In 1939 I dealt with two species of Ephialtes which parasitise the codling moth, Cydia pomonella, L., namely E. caudatus, Ratz., and E. crassiseta, Thoms., and showed how they differed from E. punctulatus, Ratz. (=extensor, Tasch.) with which species they had formerly been confused. During 1940, F. J. Simmonds, of the Imperial Institute of Entomology, sent to the British Museum a series of a species of Ephialtes bred from this same host in the south of France. This is a new species, and it was previously known to me only from a single female which had been bought by D. S. Wilkinson from O. Schmiedeknecht, who had incorrectly named it Pimpla roborator, F. In fact, this new species does not belong to the same species group as Ephialtes (Exeristes) roborator, F., Grav. (=Pimpla roborator, F., Schmied.), which is a well-known parasite of the European Corn Borer (Pyrausta nubilalis, Hb.) and also parasitises many other hosts.As there has been considerable confusion in the synonymy and interpretation of E. roborator, F., it seems advisable to give notes on the relevant type specimens seen by me. It has been impossible to find the type of Ichneumon roborator, F. Gravenhorst's interpretation of this very variable species has therefore been taken. The description given by Schmiedeknecht in his Opuscula Ichneumonologica is adequate for the recognition of the female ; the male is very distinct, having a tubercle in the middle of the clypeus, a character unknown in any other described European species. Pimpla cicatricosa, Ratz., which is given by Schmiedeknecht as a synonym of P. roborator, F., is a distinct species.
Studies of the Responses of the femaleAëdesmosquito. Part V. The Role of Visual Factors
Authors: Sippell W. L. , Brown A. W. A. 
Published: July 2009

The role of visual factors in the attractiveness of bodies to adultA. aegyptiwas investigated by exposing deer-mice in transparent or opaque, airtight or perforated, plastic containers. The visual factors proved to be roughly equivalent to the airborne emanations in attractiveness, being slightly the more attractive when the mice were normally moving, and the less attractive of the two when the mice were motionless.The attractiveness of a moving black object was found to be nearly twice that of a stationary one. A deer-mouse immobilised by anaesthesia was roughly one-half as attractive as a normally moving one.Mirroring surfaces are significantly more attractive than dull ones; a black enamel surface was more attractive than a flat black surface, and a silvered mirror more attractive than a polished metal surface. It was found that enhancement of the attractiveness of a black surface could be obtained by the movement of lines of shadow, not of points of light, across it.
Simulium damnosumand its Relation to Onchocerciasis in the Anglo-Egyptian Sudan
Authors: Lewis D. J. 
Published: July 2009

Observations were made chiefly in the southern Sudan, particularly at Mvolo where human onchocerciasis is common. The country and climate are briefly described.Methods are described at some length.The distribution ofS. damnosumand places where it is known to be abundant are shown on a map. It does not appear to exist at the Fola Rapids.Changes in certain organs were studied, chiefly in relation to the approximate estimation of age and (particularly in the case of the mid-gut and peritrophic membrane) to the movements of microfilariae. Recently emerged flies can frequently be readily detected by the clarity of the halteres (in which glycogen has not yet been stored) and the presence of abundant fat body, and by less conspicuous features such as the absence of an old peritrophic membrane. The oesophageal diverticulum often contains plant sugars and particles of grit but never blood.The peritrophic membrane is formed at the time of a blood meal by the epithelium of the expanding part of the mid-gut. It is a laminated chitinous envelope completely surrounding the blood and remains unbroken for 24 hours or more. When very large numbers of microfilariae are ingested they appear to prevent the completion of the membrane so that blood quickly passes to the hind-gut.
Aircraft Applications of Insecticides in East Africa. V.—The Deposition in open Country of a coarse Aerosol released from an Aircraft
Authors: Yeo D. , Thompson B. W. 
Published: July 2009

An investigation has been made of the deposition in open country of a coarse aerosol released from an aircraft flying at approximately 30 feet. A constant drop spectrum was used, with a mass median diameter of approximately 80 microns.It is shown that the rate at which the aerosol deposits is greatly affected by the degree of atmospheric turbulence, a practical measure of which is described. The rate of deposition is approximately inversely proportional to the time interval elapsing between production of the aerosol and deposition, except for deposits laid down near the line of emission.Droplets less than 10 microns in diameter are not deposited appreciably within any useful time interval, and it would be most uneconomical to attempt to produce deposits upon the ground by using drop spectra consisting mainly of such small droplets.The solution used was a 10 per cent. w/v solution of technical DDT in a solvent consisting of 1 part of Shell Power Kerosene to 1 part of Shell Diesoline. Evaporation of the volatile constituents takes place very rapidly during the first few seconds after production of the droplets, and deposits formed immediately beneath the aircraft track have lost 50 per cent of their initial volume. Solvent losses increase significantly with time, but so slowly that for most practical purposes the solution strength of the ground deposit is very nearly constant for all important sampling points.
Field Observations on a Breeding Place of Glossina pallidipes Austen in Kenya
Authors: Parsons B. T. 
Published: July 2009

A breeding-place of Glossina pallidipes Aust., in evergreen shrubs of Craibia sp. on the Kiangine river, Makueni, Kenya, was studied by means of hand-searching for puparia in conjunction with records of rainfall and temperature. A fly-patrol was also operated. The country away from the river was thorn-scrub, with Acacia and Commiphora trees predominating.Three sites, each of 200 sq. yards, divided into 50 squares, were marked out, and two of them were searched monthly and the third quarterly.Site “ A ” was searched nearly every month between April 1949 and June 1952, and full puparia were nearly always found. Numbers varied very widely; and it was noted that few could be found in rainy seasons during the months of November to January and April to May, though 1950 was an abnormal year. A consistently large increase in numbers was observed in February, the hottest and driest month, and a rather less marked increase towards the end of the long dry season in September and October. Large numbers of full puparia also tended to coincide with times of low average minimum temperature.The numbers of flies caught on the fly-patrol did not appear to bear any close relation to the numbers of full puparia discovered.Testing for efficiency of searching by means of marked puparia showed that about 40 per cent. of puparia were recovered, so that results must be taken as relative.
Aspects of the biology of Diclidophlebia eastopi Vondracek and D. harrisoni Osisanya (Homoptera, Psyllidae)
Authors: Osisanya E. O. 
Published: July 2009

AbstractDiclidophlebia eastopi Vondráček and D. harrisoni Osisanya are pests of the timber tree Triplochiton scleroxylon in Nigeria. The egg and five nymphal instars are described and illustrated. Under laboratory conditions the life-cycle (egg-egg) of D. eastopi was completed in 18½ days, and mated fed females had a life span of 15 days. The sex ratio in the field was 1:1. Nymphs feed near the veins of mature leaves, causing premature leaf fall; adults feed on leaves of any age and cause no symptoms. Fecundity averaged 502 eggs, with a daily oviposition rate of 38; most eggs are laid in batches along the veins of mature leaves. The life-cycle of D. harrisoni was 16 days; mated and fed females lived 10 days. The feeding of firstinstar nymphs near the margins of young leaves causes leaf tunnels to form, inside which the nymphs complete their development; adults feed only from young leaves. In the field the female:male ratio was 2:3. Fecundity averaged 131, with a daily oviposition rate of 31. Fertility improved with multiple matings. The eggs are laid singly, partially embedded in the epidermis, and only on young leaves.
Diel periodicities of landing of nulliparous and parous Aedes aegypti (L.) at Dar es Salaam, Tanzania (Diptera, Culicidae)
Authors: Corbet Philip S. , Smith Stephen M. 
Published: July 2009

AbstractThe results derive from three 24-h catches of Aedes aegypti (L.) (1190 females, 504 males) using human bait at Buguruni, Dar es Salaam, Tanzania, in April 1971. The diel periodicity of all females is predominantly diurnal (at least 99·83% arrive during daylight or twilight) and bimodal, with consistent peaks at 06.00–07.00 h (post-sunrise) and 17.00–18.00 h (pre-sunset). The diel periodicities of nullipars and pars, and of uninseminated and inseminated females are virtually identical. The diel periodicity of males is also bimodal but differs from that of females in that at least two-thirds (instead of about half) of the individuals arrive between noon and sunset, more activity occurs between 09.00 and 15.00 h, and the post-sunrise peak falls at 08.00–09.00 h. A large influx of nullipars one afternoon did little to modify the close correspondence between the diel periodicities of nullipars and pars on subsequent days. Females land on bait in all ovarian stages (I–V), but in these catches more than 80% of nullipars and pars were almost equally divided between stages I and II. Among nullipars relatively more uninseminated females, and among pars relatively more with relict eggs, land in stage I than do so in stage II. It is inferred that pars with relict eggs usually expel them between stages I and II. This work reveals the likelihood that (at least at Buguruni) the frequency of potentially infective bites on a given day could be monitored with acceptable precision by limiting the catch to seven hours and the part that was age-graded to two hours.
Observations on the Life History of Laemophloeus minutus (Ol.) (Col. Cucujidae) when bred on various Stored Cereals and Cereal Products
Authors: Williams Gwyneth C. 
Published: July 2009

Laemophloeus minutus (Ol.) has been reared on six food materials of a type with which the genus, Laemophloeus, is commonly associated in the field. Consideration of the length of egg to adult development, together with the mortality, recorded from each medium indicates that Manitoba wheat and whole-meal flour are equally favourable for the development of the species, followed in order of precedence by Plate maize, English wheat and, finally, National (85 per cent. extraction) and Canadian (70–75 per cent. extraction) flour which proved equally unfavourable.The stage of the life-history at which mortality mainly occurred varied with the diet. The high death-rate on English wheat was caused by the inability of newly hatched larvae to enter grains undamaged in the germ region. Mortality on National and Canadian flour occurred chiefly in the fourth instar.There were indications of cannibalism in both larval and adult stages, at any rate when the diet was unfavourable.The germ of wheat was attacked in preference to any other part of the grain. Maize germ was also consumed but whether it was preferred to the same extent as that of wheat was not established.Pupation was mainly, but not exclusively, intergranular in wheat. Normal cocoons were formed in National and Canadian flours but some larvae pupated in loose webbing or in flour free from webbing and freshly emerged adults were observed in unwebbed National and Canadian flour.