bluuebunny/crossref_metadata_2025_split huggingface dataset:
DDT-resistance in Plutella maculipennis (Curt.) (Lep.) in Java
Authors: Ankersmit G. W. 
Published: July 2009

The diamond-back moth, Plutella maculipennis, and Crocidolomia binotalis are the main pests of cabbage in Indonesia. Until 1951, good control was obtained with DDT sprays and dusts, but in that year growers near Lembang (Bandung) obtained poor results with DDT against P. maculipennis as compared with previous years. Investigations were started in Lembang, and also in Patjet (on Mt. Gedeh) where no difficulties had arisen. In laboratory experiments, a marked difference in susceptibility to DDT between a Lembang and a Patjet strain of P. maculipennis was demonstrated.In field tests near Patjet with DDT, BHC and toxaphene, DDT gave satisfactory control and was better than the other two. At Lembang, however, where these three materials were again tested, but with derris and pyrethrum also, toxaphene was the most effective, followed by derris and BHC, while DDT, and also pyrethrum, gave almost no control.For the time being, toxaphene and derris are recommended, the former during the growing season and the latter subsequently, but it is feared that resistance to toxaphene will develop. It may become necessary to resort to cultural and biological measures.
On the Evening Biting Activity of three neotropical Anopheles in Trinidad, British West Indies
Authors: Senior White R. A. 
Published: July 2009

Lumsden's “standard sunset” period observations have been repeated with the three commonest species of Anopheles occurring in Trinidad. The method was modified to yield data on the ovarian and fertilisation states of these three species over a period of ten months which included the dates of the latest and earliest sunset at 10°N.A. aquasalis comprised nearly 95 per cent. of a total catch of 8,592 specimens. Just over 18 per cent. of those that attacked were newly emerged, and no more than half of these were fertilised. Relict eggs, denoting a second or later gonotrophic cycle, were found in February, June and July. The 40 minutes from sunset + 20 minutes yielded nearly 80 per cent. of the total of the first two hours of activity, this period comprising nearly half the estimated total night's attack. From one hour after sunset the proportion of newly emerged specimens that attack is well below the mean. The second hour after sunset therefore provided the greatest infection risk when age, not numbers attacking, is considered.
Aircraft Applications of Insecticides in East Africa. II.—An experimental Attempt to Produce a Fly-free Corridor through a Belt of Tsetse-infested Woodland
Authors: Hocking K. S. , Parr H. C. M. , Yeo D. , Robins P. A. 
Published: July 2009

An experimental attempt was made to produce a fly-free corridor through a belt of savannah woodland containing the tsetse flyG. swynnertoni.An area two miles wide and four miles long was treated with a coarse spray of a 4·6 per cent, w/v solution of DDT in Shell Diesoline. The dosage per application was 0·5 gallons per acre, and seven applications were made, at intervals of approximately two weeks, so that the treatment covered two pupal periods.The fly density had fallen to a very low level by the end of the experiment, and the area remained virtually free from flies for the subsequent two months. An examination of the data suggests, however, that the fly population was maintained largely by immigrant flies, and was certainly subject to wide variations, and it seems certain that the effect of the applications would have been considerably less upon a stable, self-supporting population.The drop spectrum of the ground deposit had a mass median diameter of 0·35 mm., and the recovery of insecticide in the area was approximately 60 per cent. Leeward and under sides of obstacles did not receive a dose although in some cases dosages were obtained on apparently leeward sides, probably because of local reversals of wind direction.
The responses of Prostephanus truncatus (Coleoptera: Bostrichidae) and Sitophilus zeamais (Coleoptera: Curculionidae) to pheromone and synthetic maize volatiles as lures in crevice or flight traps
Authors: Hodges R.J. , Hall D.R. , Mbugua J.N. , Likhayo P.W. 
Published: July 2009

AbstractFlight traps and crevice traps for catching Prostephanus truncatus (Horn) and Sitophilus zeamais Motschulsky were studied in Kenya. The traps were baited with pheromones of these beetles, with or without synthetic maize volatiles. In the case of P. truncatus, which has a two component pheromone consisting of Trunc-call 1 (T1) and Trunc-call 2 (T2), the components were tested singly or in a 1:1 combination. The addition of synthetic maize volatiles to pheromone traps did not result in an increase in trap catch of either S. zeamais or P. truncatus. The pheromone of S. zeamais was an effective lure in both crevice and flight traps but the actual numbers captured were low. Captures with traps baited for P. truncatus were much greater. The response of P. truncatus to the two components of its pheromone was affected by the type of trap used. Crevice traps baited with either component alone caught fewer beetles than those baited with a mixture. In contrast, flight traps baited with T2 or the mixture were equally effective while traps with only T1 caught significantly fewer than either of these. These observations clarified apparent discrepancies between earlier studies in Tanzania and Mexico and are used to derive an hypothesis about the roles of T1 and T2; T2 appears to be a long-range attractant and T1 important for modifying the response to T2 to facilitate close-range orientation. Adult P. truncatus arriving at the traps were sexed, and in both flight and crevice traps the majority of captures were females even though in the experimental maize cribs the beetles were present in a roughly equal sex ratio. The role of the pheromone is discussed in the light of this observation.
Weather associated with autumn and winter migrations of rice pests and other insects in south-eastern and eastern Asia
Authors: Rutter J.F. , Mills A.P. , Rosenberg L.J. 
Published: July 2009

AbstractTrajectory analysis was used to determine the direction and extent of windborne migrations of insects trapped in autumn and winter in south-east and east Asia for 12 years between 1968 and 1987. Nearly 2600 trajectories were drawn upwind at 10 m and 1.5 km from 15 catching sites and within the time (⋜60 h), wind speed (⋝5 km h-1) and temperature (⋝10°C) thresholds used, only 5% of the trajectories failed to locate a possible source and over 90% were completed in 40 h or less. The delphacids Nilaparvata lugens Stål and Sogatella furcifera (Horváth) dominated the trap catches (96%) with Cicadellidae (2.3%) and Diptera (0.5%) as the next most numerous. Very few Lepidoptera were reported (<0.3%). Nearly 80% of the trajectories were constructed in the prevailing Winter Monsoon and Trade winds, resulting in a southward displacement of insects towards putative overwintering areas as reported in previous studies. Tropical cyclones in autumn, produced trajectories which differed in both direction and extent from those in the prevailing winds, supporting the suggestion that the contraction of the distribution areas of rice pests at this time of year is the product of a series of movements in different directions. The results suggest that migrations continue throughout the year in the tropics and sub-tropics and indicate that this may be one way the capacity for long distance migration is maintained in some rice pest populations.
Control of summer and winter diapause in Pidorus euchromioides (Lepidoptera: Zygaenidae) on Chinese sweetleaf Symplocos chinensis
Authors: Fangsen Xue , Kallenborn H. G. 
Published: July 2009

AbstractPidorus euchromioides Walker has two separate diapauses during its life cycle, a winter diapause as a fourth larval instar and a summer diapause as a prepupa in a cocoon. Winter diapause was induced by short photoperiods. The critical day length of 13 h 20 min to 13 h 40 min at 23.3°C under insectary conditions was very similar to the critical day length (13 h 32 min) observed in the field. Sensitivity to day length was restricted to the first 9 days, corresponding to the first and second instars. The duration of larval diapause was not only strongly correlated with the inducing photoperiod, but also dependent on the number of short days experienced during the larval growth period. The shortest diapause occurred at the critical day length, or when the larvae were exposed for 6 days (a critical number of short days) to a photoperiod of LD 12 h:12 h. The summer diapause appeared to be primarily determined by a genetic factor and only occurred in part of the overwintering generation and the first generation. The two different diapause mechanisms play important roles. Winter diapause ensures that P. euchromioides synchronizes its development and activity with the phenology of specific host plants, and summer diapause provides the species with a high degree of adaptation to an unpredictable environment.
Life-history parameters of different biotypes ofBemisia tabaci(Hemiptera: Aleyrodidae) in relation to temperature and host plant: a selective review
Authors: Drost Y.C. , van Lenteren J.C. , van Roermund H.J.W. 
Published: July 2009

AbstractLife-history parameters of different biotypes of the whiteflyBemisia tabaci(Gennadius) species complex were reviewed. This included the B-biotype ofB. tabaci, identified asB. argentifolii(Bellows & Perring). Comparisons were made among different biotypes on cotton, among host plants for biotype B and among the whitefly speciesB. tabaciandTrialeurodes vaporariorum(Westwood), the greenhouse whitefly. The biotype identification of different populations ofB. tabaciwas summarized in a table. Biotypes discussed were A, B, Indian and biotypes of the Old World group. Temperature dependent relationships were estimated for egg development rate, development rate from egg to adult, immature mortality, adult longevity, sex-ratio, pre-oviposition period and fecundity. The fitted curves will be used as input for a simulation model of the population dynamics ofB. tabaciin a greenhouse when parasitoids are released. The model makes it possible to evaluate the integrated effect of different life-history parameters and behavioural parameters of parasitoids on whitefly population levels in a greenhouse.
The influence of the juvenile hormone analogue (S)-hydroprene onAprostocetus hagenowii(Hymenoptera: Eulophidae), an oothecal parasitoid of the oriental cockroachBlatta orientalis(Dictyoptera: Blattidae)
Authors: Bell H.A. , Marris G.C. , Edwards J.P. 
Published: July 2009

AbstractThe synthetic juvenile hormone analogue (S)-hydroprene can control populations of the oriental cockroachBlatta orientalisLinnaeus. Eradication ofB. orientalisinfestations, however, can take in excess of two years. In an attempt to reduce the time (S)-hydroprene takes to eliminate a population of oriental cockroaches, we explored the possibility of using the oothecal endoparasitoidAprostocetus hagenowiiRatzeburg in combination with (S)-hydroprene. For such a strategy to be successful, it is important that the parasitoid remains substantially unaffected by (S)-hydroprene. WhenA. hagenowiiwas exposed toB. orientalisoothecae in the presence of (S)-hydroprene, female parasitoids showed no reduction in their capacity to attack hosts and their fecundity was not compromised. (S)-hydroprene, at dose rates of 18 mg/m2and 100 mg/m2, induced deformity in approximately 12% and 33% respectively of parasitoids that emerged. No reduction in reproductive viability was seen in morphologically normal F1parasitoids. Deformed F1parasitoids, exposed to the higher (S)-hydroprene dose, showed a 71% reduction in the number of oothecae attacked and a 50% reduction in the number of offspring produced. These results indicate thatA. hagenowiicould be used in combination with (S)-hydroprene in an integrated pest management programme againstB. orientalis.
Cytogenetic analysis of a new subcomplex of Simulium exiguum (Diptera: Simuliidae) in amazonian Ecuador
Authors: Charalambous M. , Arzube M. , Lowell S. 
Published: July 2009

AbstractTwo new cytotypes of the onchocerciasis vector blackfly Simulium exiguum Roubaud are described from amazonian Ecuador. As transmission of the disease does not occur in the region, the two cytotypes are not currently vectors, The Napo form (N = 113) differs cytologically from the chromosomal standard of the species, the Cayapa form, through possession of the fixed paracentric inversions IL-E and IIIL-L; the Huatarac form (N = 22) differs by the fixed inversions IL-L and IIIL-D + L. Both forms form a subcomplex, termed the ‘amazonian’ subcomplex, through sharing the fixed inversion IIIL-L. They also share a number of polymorphic inversions, but neither form possesses sex-linked inversions. The fixed and sex-linked inversions of the previously described Aguarico form were found to be polymorphic and autosomal in the Napo and Huatarac forms, suggesting a close genetic relationship among these forms. The Napo form is distributed throughout the Napo river system (except in the Rio Huatarac) and found in the Rio Aguarico, whereas the Huatarac form is unique to the Rio Huatarac. As their distributions in this study were allopatric, the species status of the two cytotypes could not be tested. The Aguarico form was not found in the Rio Aguarico, nor in any of the other rivers sampled. Whether the Napo form has replaced the Aguarico form in the Rio Aguarico, or whether its absence is due to seasonal variation requires further investigation.
Does a repellent effect contribute to reduced levels of insect activity in dung from cattle treated with ivermectin?
Authors: Floate K.D. 
Published: July 2009

AbstractA two-year pitfall trapping study was performed to test the preference of coprophilous beetles (Hydrophilidae, Scarabaeidae, Staphylinidae) for dung from untreated cattle versus dung from cattle treated topically one or four weeks previously with a recommended dose of ivermectin in a pour-on formulation. In 1994, significantly more Aphodius fimetarius (Linnaeus) and A. distinctus (O.F. Müller) at each of two sites were collected with dung from treated cattle. No differences were detected for other taxa. In 1995, significantly fewer individuals of ten taxa, including A. fimetarius and A. distinctus, were collected with dung from treated cattle. No differences were detected for other taxa. A change in cattle diet may have altered levels of faecal residues, thereby changing beetle preferences between years. Comparisons between periods of spring and autumn activity identified a change in seasonal preferences for at least some species. Similar numbers of Onthophagus nuchicornis Linnaeus and of A. fimetarius were collected in spring with dung from treated or untreated cattle, but significantly more individuals of both taxa were collected in autumn with dung from untreated cattle. In contrast, the preference of Aphodius prodromus Brahm for dung from treated cattle was unchanged between spring and autumn. These results show that ivermectin therapy does influence the colonization of dung from treated cattle. However, the nature of this influence is confounded by extraneous factors. Until such time that these factors can be accounted for, general predictions regarding the effect of ivermectin therapy on the colonization of dung by coprophilous insects are premature.
The effectiveness of exclusion barriers for polyphagous predatory arthropods in wheat
Authors: Holland J.M. 
Published: July 2009

AbstractVertical polythene exclusion barriers combined with trapping out using pitfall traps have been used to create enclosures within which arthropod numbers can be manipulated. This technique has been primarily used to investigate the impact of ground-dwelling polyphagous arthropods on cereal pests. Arthropod numbers in a total of 42 enclosed areas were compared to adjacent unenclosed areas over three years in Hampshire, UK. A range of arthropod monitoring techniques was used, including pitfall traps, fenced pitfall traps and D-vac suction samples. The enclosures were effective in reducing most species of Carabidae, Linyphiidae and Lycosidae encountered and numbers in pitfall traps were reduced by an average of 74%, 62% and 77% respectively. Similar reductions in densities of these taxa were found. Staphylinidae were less effected with an average reduction of only 32% in pitfall traps, although Philonthus species were reduced by 82%. Results were compared to previous studies.
Aphids on cabbage: tritrophic and selective insecticide interactions
Authors: Verkerk R.H.J. , Neugebauer K.R. , Ellis P.R. , Wright D.J. 
Published: July 2009

AbstractLaboratory-based experiments are presented involving two aphid sepcies (Myzus persicae Sulzer, a generalist and Brevicoryne brassicae Linnaeus, a crucifer specialist), and the predatory gall midge, Aphidoletes aphidimyza Rondani, on three cultivars of common cabbage Brassica oleracea var. capitata cv. Derby Day (green-leaved), Minicole (green-leaved) and Ruby Ball (red-leaved). In a laboratory-based tritrophic system including both species of aphid, the three cabbage cultivars and A. aphidimyza, predator both species of aphid, the three feeding on M. persicae or B. brassicae on cv. Derby Day, while growth was slowest separate experiment, A. asphidimyza larva feeding on B. brassicae on each of the three cultivars were significantly smaller and consumed less aphid fresh weight when maintained outdoors (mean temperature = 13.5°C) compared with a constant environment room (20°C). However, in this latter experiment under neither regime were differeneces in predator growth or consumption significant between cultivars. Effects of selective insecticides (pirimicarb and a neem seed kernel extract, NeemAzal-T/SR) on bitrophic (aphid-host plant) interactions were also investigated in the laboratory. A pirimicarb dose equating to c. 15% of the recommended field concentration caused equivalent toxicity of M. persicae on cv. Minicole compared with aphids treated with a three-fold greater dose and reared on cv. Derby Day. Cultivar-mediated differences in aphid mortality caused by the neem extract when tested for systemic and translaminar activity were not apparent. The results are discussed in relation to ways in which host plant selection, selective insecticides and biological control could potentially be manipulated and optimized in aphid management system on brassica crops.
The potential for manipulating crop–pest–natural enemy interactions for improved insect pest management
Authors: Verkerk R.H.J. , Leather S.R. , Wright D.J. 
Published: July 2009

AbstractThis review identifies key ways in which manipulations of the crop environment based on detailed understanding of tritrophic interactions can contribute to improvements in the control of insect pests. Such approaches are likely to be of particular benefit against those pests, notably certain species of Lepidoptera and aphid, which are difficult to control with insecticides because of insecticide resistance or suppression of natural enemies. Particular attention is given to the compatibility (or otherwise) of partial plant resistance and biological control, citing examples which support contrasting tritrophic theories. Other areas considered and supported with examples include the use or effects of allelochemicals, refugia, intercropping, crop backgrounds, fertilization regimes, parasitoid conditioning (by host plants) and transgenic crops. Examples of manipulations involving use of selective insecticides which show compatibility with biological methods are also included owing to their possible suitability in integrated crop management programmes.
Genetic variability within and between English populations of the damson–hop aphid,Phorodon humuli(Hemiptera: Aphididae), with special reference to esterases associated with insecticide resistance
Authors: Loxdale H.D. , Brookes C.P. , Wynne I.R. , Clark S.J. 
Published: July 2009

AbstractThe damson–hop aphid,Phorodon humuli(Schrank), is a serious pest of hops in England. It is holocyclic (with obligatory sexual phase) and host alternating. From suction trap data,P. humuliaerial densities are known to be greatest in the main hop growing regions of Herefordshire and Kent (mid-west and south-east England, respectively), some 260 km apart. The aphid is now resistant to several insecticides. This is in part conferred by elevated carboxylesterase activity, ranging from low in susceptible to high in very resistant strains. Enzyme markers, including carboxylesterases (EST-4 to -7), separated electrophoretically from individual insects, have been used to examine the degree of genetic heterogeneity amongP. humulisub-populations on both its hosts –Prunusspp. (primary overwintering host) and hops,Humulus lupulus(secondary summer host). The esterase data revealed heterogeneity among subpopulations collected from wild, unsprayed hosts in regions less than 30 km in area, with a higher mean frequency of elevated esterase variants in the commercial hop growing regions of Herefordshire and Kent, compared with samples from a non-commercial region around Rothamsted. Esterase distributions remained similar over consecutive years. Similarly, allele and genotype frequencies for another enzyme (6-phosphogluconate dehydrogenase, 6-PGD) were also heterogeneous among subpopulations sampled at less than 30 km apart (especially fromPrunus) in each of the three regions surveyed, whilst allele and genotype frequencies sometimes remained stable over a number of summers. In addition, 6-PGD genotype frequencies were mostly congruent with Hardy-Weinberg expectations, even for parthenogenetically-reproducing aphids colonizing hops. These data suggest that the 6-PGD alleles tested are selectively neutral; that gene flow (=migration) is restricted between aphid populations, even within a single region (≤ 30 km) and, that the autumn migration from hops toPrunusis probably of shorter range (perhaps less than 20 km) compared with the spring migration fromPrunusto hops.
Evidence of density-dependent oviposition behaviour byListronotus bonariensis(Coleoptera: Curculionidae) in Canterbury pasture
Authors: McNeill M.R. , Baird D.B. , Goldson S.L. 
Published: July 2009

AbstractArgentine stem weevil (Listronotus bonariensis) (Kuschel) is a pasture pest ofLoliumspp. in New Zealand and is the target of a classical biological control programme using the parasitoidMicroctonus hyperodaeLoan. However, laboratory experiments have indicated a strong density-dependent egg laying response which may have important implications for the biological control effort. Two field experiments were conducted using a manipulated range of weevil densities within 2.0–2.4 m–2field enclosures and oviposition activity measured by weekly sampling of grass tillers within the enclosures. In both experiments, density had no effect on general oviposition behaviour although the percentage of tillers found to be infested with eggs increased significantly at higher densities. In experiment 1,L. bonariensisexhibited strong density-dependent oviposition with a significant decline in eggs/tiller/female with increasing adult density. An initial population of fiveL. bonariensism−2oviposited 32 times more eggs/tiller/female than 200L. bonariensism−2. By comparison, density-dependent oviposition was absent in experiment 2 with eggs/tiller/female comparable for all densities. The dramatic difference between the two experiments in the expression of density-dependent oviposition was attributed to prevailing spring temperatures during the sampling interval, which in the second experiment were much cooler and delayed the onset of egg laying. It is probable that in experiment 2, oviposition was not regulated by density-dependent cues but limited by temperature and age related mortality in the adult population. The mechanism for density-dependent oviposition, its occurrence in the field and impact on the effectiveness of the parasitoidM. hyperodaeare discussed.