bluuebunny/crossref_metadata_2025 huggingface dataset:
Axenic culture of the foreign grain beetle,Ahasverus advena(Waltl) (Coleoptera, Silvanidae), and the rôle of fungi in its nutrition
Authors: Hill S. T.
Published: July 2009

The extent of the dependence of the foreign grain beetle,Ahasverus advena(Waltl), upon moulds in its diet was investigated.

Using a simple technique, the insect was cultured axenically at controlled temperature and relative humidity on an autoclaved mixture of rolled oats, wheatfeed and dried yeast. After the mixture was sterilised by exposure to propylene oxide vapour, virtually no larvae completed development on it in the absence of living micro-organisms, and this effect was unchanged by the addition of a mixture of B-vitamins followed by autoclaving. However, when fungi were grown on the food previously sterilised with propylene oxide, it again permitted the complete development of the insect.

Autoelaved wheat germ was not a suitable diet forA. advenaunless a small proportion of dried yeast was added before autoclaving. It is concluded that living fungi are not essential in the diet of the insect, but that they may supplement an otherwise inadequate diet.

The minimum development time from egg to adult on a complete food at 80 per cent. E.H. and 30°C. varied from 18 to 25 days.
Laboratory culture of a Tettigoniid, Homorocoryphus nitidulus vicinus (Wlk.) (Orthoptera)
Authors: Hartley J. C.
Published: July 2009

A method is described by which Homorocoryphus nitidulus vicinus (Wlk.) was reared in numbers continuously in the laboratory. This is believed to be the first account of the continuous labouratory culture of a Tettigoniid. Details are given of a substitute oviposition site that enables the eggs to be easily collected. The basic food used was grass, which was supplemented with cereals. The problem of cannibalism and methods of reducing it are discussed. Brief information on the bionomics of the crickets under these conditions is included.
Studies on Bathycoelia thalassina (H.-S.) (Hemiptera; Pentatomidae), the cause of premature ripening of cocoa pods in Ghana
Authors: Lodos N.
Published: July 2009

Bathycoelia thalassina (H.-S.), of which the developmental stages and life history are described, is responsible for premature ripening of cocoa pods in Ghana. Experiments conducted at Tafo to determine the nature of the damage to pods showed that the insect feeds directly on the beans, and that beans so attacked turn brown and subsequently die: only the empty shell of the bean remains.

The saliva of the insect kills any tissue of the pod that it penetrates and within four days the injured areas cease to grow and become yellow, then brown, and finally black.

The symptom most characteristic of damage is the change in colour. The pod may become completely yellow, or yellow in the basal or distal half only (usually the latter) or yellow in spots, depending on the size of the pod, the site of attack, and the duration of feeding at each site.

The insect usually attacks pods of the Amazon varieties, 10–17 cm. long. The incision made by the stylets is microscopic, and is covered by a jelly-like substance, and no evident lesions develop on the surface as in damage caused by cocoa mirids or coreids.

Damage caused by B. thalassina on young pods resembles cherelle wilt of physiological origin, and the two can be distinguished only by slicing the pods, whereupon the former can be recognised by the presence of injured beans.

According to the survey of damage caused by B. thalassina in Ghana, this species seems to be an economic pest on some Amazon and hybrid types of cocoa, whereas Amelonado cocoa usually suffers little.
A new genus and species of Thysanoptera predatory on mites in Iraq
Authors: Mound L. A.
Published: July 2009

A new species of thrips is described which is predatory on Tetranychid mites on apple trees in Iraq. It bears a superficial resemblance to species of Scolothrips, but in view of the undivided tarsi and the chaetotaxy of teh head and pronotum it is placed in a new genus as Parascolothrips priesneri sp.n.
Funnel ants (Aphaenogaster spp., Formicidae) as pasture pests in North Queensland. I.—Ecological background, status and distribution
Authors: Saunders G. W.
Published: July 2009

In a study of the incidence of funnel ants (Aphaenogaster spp.) on the Atherton and Evelyn Tablelands of northern Queensland in 1959–61, 422 farms were surveyed, totalling over 98,000 acres of pasture, of which 10.8 per cent. proved to be infested with A. pythia Forel. The ants damage the introduced pasture grasses (Paspalum dilatatum and Pennisetum clandestinum) by removing soil from around their roots to from loose mounds, which smother the closely-grazedsward. Inferior species of grass and deep-rooted weeds are thus encouraged and affected areas become useless for dairying.

The natural habitat of A. pythia is wet sclerophyll forest which occurs in narrow belts fringing the rain forest and in pockets within it; the rain forest does not harbour the ant, but following its clearance and its replacement by pastures, A. pythia has spread out and colonised the latter. In areas of lower annual rainfall (under 50 in.) occupied dry sclerophyll forest and Eucalyptus woodland, A. pythia is replaced by A. longiceps F. Smith. Improved pastures have not been established here, but in the relatively restricted areas of infestation by this species, the large funnel-shaped orifices of its mounds create a hazard to stock.
Effect of temperature and humidity on the development of tea red spider mite, Oligonychus coffeae (Nietner)
Authors: Das G. M. , Das S. C.
Published: July 2009

The effects of temperature and humidity on the development of Oligonychus coffeae (Nietner) were studied by exposing the various stages of the mite to air in equilibrium with saturated solutions of appropriate salts in containers within thermostatically controlled cabinets. Adults and early stages were maintained on fresh tea shoots.

The pre-oviposition, oviposition and post-oviposition periods of adult females at 75–80% relative varied inversely with temperature, and averaged, respectively, 0.8, 5.9 and 1.4 days at 32° and 2.3, 30.6 and 2.0 days at 20°C. The mean number of eggs laid per female likewise varied inversely with temperature, from 12.0 at 32°C at 32° to 107.3 at 20°C.

No eggs hatched when incubated at 34°C., irrespective of humidity, or at 17% R.H., irrespective of temperature. Optimum conditions for incubation (those affording over 90% hatch) were provied by a combination of temperatures and relative humidities within the ranges 20–30°C. and 49–94%. When eggs were exposed daily for five days to temperatures of 37 or 40° for six hours at 72–94% R.H. and then transferred to room conditions (24–32°C., 64–88% R.H.), the percentage of eggs hatching was reduced from 94.7 (room conditions) to about 75 or 5–12, respectively.

The mean incubation period of eggs varied from 3.9 days at 32° to 10.8 at 20°C., and the mean duratio of the combined larval and nymphal stages from 4.9 days at 30° to 8.7 at 20°C. At 32°C., larval mortality was very high.
Ticks (Acari: Ixodoidea) in Botswana
Authors: Paine Gordon D.
Published: July 2009

In a survey in 1976–79 in Botswana, more than 14000 adult ticks were collected from cattle and other domestic and wild animals and identified. Larvae and nymphs were also collected but not counted. Comparison with previous records indicates that some species, particularly Amblyomma hebraeum Koch and Boophilus decoloratus (Koch), are becoming more numerous and widespread, probably due to cattle movements and favourable climatic conditions. Haemaphysalis aciculifer Warb. was found for the first time in Botswana. The counts from complete collections of ticks from groups of three cattle are analysed, host-parasite lists are given and the results of a few acaricide resistance tests are recorded.
Chemosterilisation ofGlossina morsitans morsitansWestwood andG. PallidipesAusten (Diptera: Glossinidae) in the field
Authors: House A. P. R.
Published: July 2009

Wild adults ofGlossina morsitans morsitansWestw. andG. pallidipesAust. were caught in a trap baited with carbon dioxide and acetone near Chimotsi Dam in the Zambezi Valley, Zimbabwe. The design of the trap was such that flies were induced to move into a sterilising chamber, where they were treated with a spray of the chemosterilant metepa, after which they were automatically released back into the environment. Exposure to a spray of 0·2 s duration produced between 94 and 100% sterility, with very low mortality. The sterilising unit, its action and performance are described.
The improvement of traps for tsetse flies (Diptera: Glossinidae)
Authors: Vale G. A.
Published: July 2009

Based on previous studies of the trap-orientated behaviour of Diptera, a variety of new traps was designed to maximise the speed and probability of capturing Glossina morsitans morsitans Westw. and G. pallidipes Aust. arriving near traps, and to minimise the probability of capturing other flies. In Zimbabwe, catches were made with these traps in the presence and absence of carbon dioxide and acetone as odour attractants, leading to the identification of a simple trap for which the probability of capturing Glossina spp. was up to twice as great as it was for a standard biconi-cal trap, and for which the probability of capturing other Diptera was very much less than it was for the biconical trap. The probability of capture by the simple trap was 100% for G. pallidipes, 51% for G. m. morsitans, 6% for Stomoxyinae and 1% for non-biting Muscidae. Half the tsetse that arrived near the simple trap were captured within 5 min of arrival. The number of tsetse that contacted simple targets designed to expose flies to insecticide amounted to 32–263% of the catches of a biconical trap. The use of traps and targets for tsetse control, and the procedures for trap improvement, are discussed.
Flight and settling behaviour ofRhopalosiphum Padi(L.) (Hemiptera: Aphididae)
Authors: Wiktelius S.
Published: July 2009

Alate exules ofRhopalosiphum padi(L.) were flown in a flight chamber for three different flight times: 1 min, 5 min and 25 min. The rate of climb was recorded continuously during flight. Afterwards, the aphids were forced to land on either wheat or potato and settling behaviour was recorded. The settling response was strengthened with increasing flight time on both plants. The aphids spent more time walking and made more probes on potato than on wheat after 25 min of flight. The rate of climb was the same immediately before landing as immediately after a spontaneous re-take-off, except after a 25-min flight and landing on potato when the rate of climb was significantly higher after re-take-off. Comparison withAphis fabaeScop. from other investigations showed that the change in settling response with flight time was similar for the two species.R. padiseemed less able to discriminate rapidly between host and non-host plants thanA. fabae. It is concluded that its behaviour does not hinderR. padifrom being a vector of stylet-borne potato viruses.
Influence of Scirpophaga incertulas (Lepidoptera: Pyralidae) on deepwater rice
Authors: Islam Zahirul
Published: July 2009

The influence of the lepidopteran stem borer Scirpophaga incertulas (Walker), the most important pest of deepwater rice (Oryza sativa) in south-east Asia, on plant and grain yield was investigated in Bangladesh during 1982–85. Four mechanisms of crop loss were identified: (i) deadhearts at the vegetative stage, (ii) loss of damaged but apparently healthy stems in flood water, (iii) white-heads at the reproductive stage and (iv) the effect of late season stem damage on panicles. A great proportion of damaged stems was not visible and damage symptoms were found to be an unreliable indicator for the assessment of borer activities in the field, and did not represent the actual yield loss. Stem damage had a negative influence on the stem density, with reduced panicle density and grain yield. Stem borer damage also seemed to reduce the elongation ability of the rice stem causing them to rot. Late season stem damage reduced the number of filled grains, mean grain weight and panicle weight and increased grain sterility. These effects were related to severity and position of damage. The average estimated yield loss due to S. incertulas was about 17% which took place during the last 11 weeks (from flood peak to crop maturity) of the deepwater rice season (32 weeks).
Termite (Isoptera) control in agriculture and forestry by non-chemical methods: a review
Authors: Logan James W.M. , Cowie Robert H. , Wood T.G.
Published: July 2009

Non-chemical control of termites in agriculture and forestry is attracting renewed interest following increasing restrictions on the use of persistent organochlorine (cyclodiene) insecticides. Non-chemical control involves methods which attempt, without using commercial pesticides, to (i) prevent termite access to the plants, (ii) reduce termite numbers in the vicinity of the plants or (iii) reduce susceptibility/increase resistance of the plants themselves. There have been few adequate trials of any of these methods. Numerous cultural procedures have been suggested, including measures to enhance plant vigour, to manipulate termite numbers and behaviour, and others whose mode of action is unclear. Many are simply part of good agricultural/silvicultural practice and to be recommended. Biological control by predators or pathogens is unlikely to be successful due to the termites' social structure and behavioural responses to infected individuals and to loss of individuals to predators. The use of ‘natural’ insecticides from locally available plant products may be effective in some cases but, as they are not subject to the same rigorous safety and environmental evaluation as commercial pesticides, their use cannot be sanctioned unconditionally. Other locally available products, e.g. wood ash, have not been adequately evaluated. Removal of reproductives from the nest and construction of physical barriers may have limited applications, but resistant species and varieties, combined with appropriate cultural methods and, perhaps, minimal use of modern pesticides in an integrated approach, offer the greatest potential for a long term solution. The lack of critical scientific evaluation of non-chemical control makes it a field wide open for research.
The effect of temperature and relative humidity on population growth of three Liposcelis species (Psocoptera: Liposcelidae) infesting stored products in tropical countries
Authors: Rees D.P. , Walker A.J.
Published: July 2009

The effect of a range of temperatures (15–42°C) and relative humidities (40–80%) on growth of populations of Liposcelis entomophilus (Enderlein), Liposcelis bostrychophilus Badonnel and Liposcelis paetus Pearman infesting a rice-based medium was investigated. These species are often found infesting stored cereal grains in the tropics. Both L. entomophilus and L. bostrychophilus bred most rapidly at 30°C, 70–80% r.h. Neither survived at temperatures of 36°C and above. In contrast, L. paetus bred most rapidly at 33–36°C, 70% r.h., and was able to breed at 42°C, 80% r.h. No species survived humidities below 60%. As well as consuming mould growth, Liposcelis spp. also caused visible damage in rice grains. Implications of these findings in the understanding of pest status and geographical distribution of severe outbreaks of Liposcelis spp. are discussed.
Biology of Bucculatrix parthenica Bradley sp. n. (Lepidoptera: Bucculatricidae) and its establishment in Australia as a biological control agent for Parthenium hysterophorus (Asteraceae)
Authors: McClay A. S. , McFadyen R. E. , Bradley J. D.
Published: July 2009

Bucculatrix parthenica Bradley sp. n., a moth native to Mexico, is described. It has been released and established in Queensland, Australia, as a biological control agent for its host plant, Parthenium hysterophorus. The moth oviposits on leaves of its host. First and second instar larvae are leaf miners, and later instars feed externally on the leaves. The life cycle occupies about 25 days under field conditions. B. parthenica was narrowly oligophagous in host-specificity tests. In Mexico the insect is scarce but in Queensland it has become abundant enough to cause extensive defoliation of its host plant at some sites. Its rapid increase in Queensland is attributed to the absence of parasitism.
‘Rhyzobius ventrails’ (Coleoptera: Coccinellidae), its constituent species, and their taxonomy and historical roles in biological control
Authors: Pope R. D.
Published: July 2009

TheRhyzobius(orLindorus)ventralisfrequently referred to in the literature of biological control is shown to be a mixture of two distinct, though similar, species. The origin of the confusion is traced to the nineteenth century searches in Australia for insects to control scale insect infestations on citrus and other crops in California. Adults of the two species are defined and illustrated, and a key is provided for their separation. Lectotypes are designated forR. ventralis(Erichs.), its synonymScymnus restitutorSharp and forS. halliBroun, newly synonymised withR. ventralis. A lectotype is designated forPlatyomus forestieriMuls., the second species of the complex, here transferred toRhyzobius, and forS. circularisSharp, newly synonymised withR. forestieri. Distribution data for both species, based on actual specimens examined, are listed, and their Australian distribution is summarised in a map. Past usages of ‘R. ventralis’ as a biological control agent are reviewed in the light of the revised taxonomy. The taxonomy and nomenclature ofRhyzobiusStephens is discussed in order to establish the correct generic placement of and binomina forR. ventralisandR. forestieri.
Long-term survival of introduced genes in a natural population of Aedes Aegypti (L.) (Diptera: Culicidae)
Authors: Lorimer Nancy
Published: July 2009

A population of Aedes aegypti (L.) near the Kenya coast was monitored for nearly a year after a genetic control experiment. Two genetic markers that were carried by released males but unknown to the region persisted in the population during the entire period of observation. The endurance of introduced genetic material in a natural population is an important step toward the use of genetic control in insect management.
Organophosphate resistance in vector Populations of the complex of Culex Pipiens L. (Diptera: Culicidae)
Authors: Curtis C. F. , Pasteur N.
Published: July 2009

Resistance to chlorpyrifos and other commonly used organophosphate larvicides was found in Culex quinquefasciatus Say from several urban areas in Tanzania. Lower levels of resistance were found in laboratory strains of the complex of C. pipiens L. collected in Sri Lanka, Egypt, Liberia and Brazil. Crosses of the Tanzanian strains to a more susceptible strain gave results consistent with causation of the resistance by a single gene or closely linked group of genes. Electrophoresis of one of the Tanzanian stocks indicated two esterase bands of high activity. The resistance in Tanzania did not prevent larval killing by freshly sprayed chlorpyrifos, but it is suggested that a spraying would probably no longer remain effective for three months as reported in earlier field studies.
Hyperparasitism in two newly introduced parasitoids,Epidinocarsis lopeziandGyranusoidea tebygi(Hymenoptera: Encyrtidae) after their establishment in Togo
Authors: Agricola U. , Fischer H.U.
Published: July 2009

In 1988/89 the nature and degree of hyperparasitism in two newly introduced parasitoids of exotic mealybug plant pests were examined in Togo. Associated withPhenacoccus manihotiMatile-Ferrero (Hemiptera: Pseudococcidae) (cassava mealybug) five indigenous hymenopterous hyperparasitoids were found adapted to the primary parasitoidEpidinocarsis lopezi(De Santis):Chartocerussp. A (Signiphoridae),Prochiloneurus insolitus(Alam),P. aegyptiacus(Mercet) (Encyrtidae),Tetrastichussp. (Eulophidae), andMarietta leopardinaMotschulsky (Aphelinidae). The rate of hyperparasitism varied considerably (20–90%). At one sampling siteChartocerussp. A was most frequent (52%), at the other siteP. insolituswas found to dominate (55%). The same hyperparasitoids were associated withRastrococcus invadensWilliams (Hemiptera: Pseudococcidae), but with an additionalChartocerus(sp. B). Hyperparasitism ranged from 56 to 86%, withChartocerussp. A being the most important species. Multiple parasitism was observed on several occasions. In spite of generally high hyperparasitism, no detrimental effect on the control efficiency of either primary parasitoid was noticed.
A method for determining the age of very young tsetse flies (Diptera: Glossinidae) and an investigation of the factors determining head fluorescent levels in newly emerged adults
Authors: Msangi Atway , Lehane M.J.
Published: July 2009

The new age determination technique for tsetse flies based on the accumulation of fluorescent pigments in the head capsule has the minor problem that it is not possible to accurately identify very young flies. In this paper we describe a technique for the identification of very young Glossina morsitans morsitans Westwood based on their high levels of abdominal fluorescence. Under our holding conditions these fall back in a linear fashion to a minimum at five days post-emergence. The variability in the levels of head fluorescence at eclosion is mainly influenced by the size of the emerging fly, with the number of blood meals taken by the female parent, and intra-uterine larval and puparial periods of the emerging flies also playing a part.
Evaluation of insecticides in field-control simulators and standard laboratory bioassays against resistant and susceptible Bemisia tabaci (Homoptera: Aleyrodidae) from Sudan
Authors: Rowland Mark , Hackett Barbara , Stribley Mary
Published: July 2009

Cypermethrin, profenofos, and a mixture of these insecticides were evaluated against resistant and susceptible whitefly, Bemisa tabaci Gennadius, from Sudan using (a) laboratory technology which simulates the aerial spraying of whitefly infestations on cotton crops, and (b) standard residue-bioassays. Simulator tests in which adult cohorts were given a single insecticide treatment produced results that were unexpected on the basis of standard bioassay data. Resistance to cypermethrin, for example, was expressed in the bioassays but not in the simulator, resistance to profenofos was expressed both in bioassays and in the simulator, resistance to the mixture was expressed in the simulator but in the bioassay the chemicals acted synergistically and there was no resistance. Repeated treatment of resistant populations, comprised of all life stages, over three generations gave further unpredicted results: cypermethrin failed to contact larvae on the under surfaces of leaves and hence did not prevent population growth; profenofos sprayed at field rates controlled all life-stages (despite the expression of resistance) provided the insecticide vapour was not dissipated. An alternation of cypermethrin and profenofos – cypermethrin timed against maximum adult emergence and profenofos timed to coincide with high larval densities – gave the best control. The disparities between the simulator experiments and standard bioassays suggest that techniques simulating the field treatment of all life-stages are better suited for evaluating the practical significance of resistance and potential curative strategies.
The Palaearctic species of Eurytoma (Hymenoptera: Eurytomidae) developing in stone fruits (Rosaceae: Prunoideae)
Authors: Zerova M.D. , Fursov V.N.
Published: July 2009

Species of the chalcidoid genus Eurytoma associated with stone fruits are studied for the Palaearctic region. The eight species known to have such an association are: E. amygdali Enderlein, E. maslovskii Nikol'skaya, E. padi Veresh-chagin, E. samsonowi Vasiljev, E. schreineri Schreiner, E. turkestanica sp. n., E. paramygdali sp. n. and E. armenica sp. n. The first six species are phytophagous, developing in the stones, and the last two are entomophytophages, starting their development as parasitoids of a phytophagous species and completing development feeding on plant tissue. Four species, E. amygdali, E. schreineri, E. samsonowi, and E. maslovskii are of economic importance. Information is given on the economic importance, biology, distribution and taxonomy of these species, and includes several new records for hosts and distribution. A key is given to distinguish the species.
Field studies on the biology and economic importance of Pachnoda interrupta (Coleoptera: Scarabaeidae) in Mali, west africa
Authors: Grunshaw J.P.
Published: July 2009

A description is given of the life history, biology and feeding habits of the cetoniine beetle Pachnoda interrupta (Olivier) (Coleoptera: Scarabaeidae) studied in pearl millet (Pennisetum glaucum) fields in north-west Mali. The third instar larva of this beetle, reared from the progeny of field captured adults, is also described and figured. Yield losses to a range of beetle densities (1–5 and 10 beetles/head) on millet heads have been estimated to range from 9 to 48% in caged trial experiments. The regression equation generated from these data may be used to establish economic injury thresholds and predict losses resulting from varying beetle densities.
Control of termites and other soil pests of groundnuts with special reference to controlled release formulations of non-persistent insecticides in India and Sudan
Authors: Logan J.W.M. , Rajagopal D. , Wightman J.A. , Pearce M.J.
Published: July 2009

Trials for the control of soil pests, particularly of termites (Isoptera: Termiti-dae), in groundnuts (Arachis hypogaea) in India and Sudan used chlorpyrifos and isofenphos granules, chlorpyrifos, phorate, carbosulfan and carbofuran in controlled release formulations, and chlorpyrifos seed dressing. Their effects on foliar pests were also noted. Chlorpyrifos controlled release pellets were as effective as aldrin, used as a standard, in reducing root and pod attack and, like aldrin, doubled yields. Isofenphos and chlorpyrifos granules increased yields and reduced pod damage, but to a lesser extent. Other treatments were less effective. Carbosulfan and phorate controlled release and isofenphos granules reduced leaf miner attack. These trials establish the efficacy of controlling termites and other soil pests with controlled release formulations of otherwise non-persistent insecticides. However, the expensive formulation is unlikely to be cost-effective for rural farmers in developing countries and, in the case of chlorpyrifos, residue levels in kernels may be unacceptable. Future work should investigate other insecticides in the formulation and development of cheaper controlled release matrices.
Factors affecting the emergence of Hypothenemus hampei (Coleoptera: Scolytidae) from coffee berries
Authors: Baker P.S. , Ley C. , Balbuena R. , Barrera J.F.
Published: July 2009

Emergence of coffee berry borer, Hypothenemus hampei (Ferrari), from infested coffee berries (Coffea arabica) was studied in the laboratory under controlled temperature and relative humidity (RH) regimes. Low humidities (<60% RH, 25°C) provoked rapid evacuation of adults. Emergence was at a minimum at 90% RH. A steady increase in emergence occurred at values from 90 to 100% RH. Emergence was low below 20°C (90 and 100% RH) and increased markedly between 20 and 25°C. There was no significant increase in emergence above 25°C. Using a simple flight event recorder, emergence flight times were found to peak at the time of maximum daily ambient temperatures on successive days. Under constant temperature conditions successive peaks of emergence were not seen. Results are discussed in relation to control and sampling procedures.
Ivermectin excreted in cattle dung after subcutaneous injection or pour-on treatment: concentrations and impact on dung fauna
Authors: Sommer C. , Steffansen B. , Nielsen B. Overgaard , Grønvold J. , Vagn Jensen K.-M. , Brøchner Jespersen J. , Springborg J. , Nansen P.
Published: July 2009

Heifers were treated with the recommended doses of ivermectin: 0.2 mg/ kg bw by subcutaneous injection or 0.5 mg/kg bw by pour-on. An analytic procedure is described and used for the detection of ivermectin residues excreted in dung. A large amount of the higher pour-on dose was excreted during the first five days after dosing due to a more rapid distribution to intestinal contents. Later faecal concentrations after the pour-on treatment were lower than those found after subcutaneous injection. No degradation of ivermectin was detected in pats exposed in the field for up to 45 days. Ivermectin excreted in dung voided 1–2 days after both treatments significantly reduced the number of dung inhabiting larvae ofAphodiusspp. (Coleoptera: Scarabaeidae), but no effect was seen in dung deposited 13–14 days after treatments. Development of cyclorrhaphan larvae was inhibited in dung deposited up to 28–29 days after subcutaneous injection treatment, but only inhibited in dung deposited up to 13–14 days after pour-on treatment. The numbers of Nematocera larvae were not affected. In a laboratory bioassay the DipteraMusca autumnalisDeGeer andHaematobia irritans(Linnaeus) suffered higher mortality in dung from heifers treated by the subcutaneous injection 13–14 days earlier than in dung from heifers treated by pour-on at the same time. After subcutaneous injection, a significant reduction in the rate of decomposition was found in dung from heifers treated 1–2 days earlier, whereas pour-on led to a delayed decomposition in dung collected up to 13–14 days after treatment.
Avermectins: a review of their impact on insects of cattle dung
Authors: Strong L.
Published: July 2009

Avermectins administered to cattle for control of parasitic infections by injection or slow-release bolus are excreted in the faeces and have a variety of harmful effects upon Diptera and Coleoptera that develop in cow-pats: these effects are reviewed. Diptera Cyclorrhapha are severely affected, the extent of the response depending on the drug concentration in the dung. At high levels, larvae are killed or paralysed while at lower levels their metamorphosis is inhibited. At very low levels, adult emergence is reduced and a significant number of imagines show morphological abnormalities. These responses are induced by concentrations of avermectins well below levels occurring in faeces after routine treatment. Diptera Nematocera are less sensitive than Cyclorrhapha but larval and pupal development are affected at higher dose levels. Larval dung beetles and some immature adults cannot survive in the pats of recently dosed livestock. Mature adult beetles are more resistant, but contact with treated dung leads to impaired reproduction. Dung eliminated up to 5 weeks after cattle have been treated with a single injection or up to 14 days after topical dosing shows harmful activity against dung insects, and ivermectin-containing pats retain much of their toxicity after several weeks exposure on pastureland. The impact on dung insects is more pronounced and of longer duration when ivermectin is delivered daily at 40 μg per kg cow by sustained-release bolus. Following topical or injection treatments, the rate of cow-pat degradation (measured by actual loss of biomass) is significantly delayed. When cattle are treated with a bolus delivering 40 mg ivermectin per kg cow per day, their dung remains intact on grassland for at least three months. The conclusions drawn from the various papers on these effects are compared and contrasted. In particular, attention is drawn to the general failure to recognize the importance of delayed reactions to non-lethal doses of avermectins, and to our lack of consideration of long-term consequences for cow-pat insects and the wider implications for ecology.
Analysing host location inUscana lariophaga(Hymenoptera: Trichogrammatidae), an egg parasitoid of bruchids (Coleoptera: Bruchidae), using Cox's proportional hazards model
Authors: Ormel G.J. , Gort G. , van Alebeek F.A.N.
Published: July 2009

Uscana lariophagaSteffan is an egg parasitoid of the bruchid speciesCallosobruchus maculatus(Fabricius) andBruchidius atrolineatusPic in West Africa, which cause damage in stored cowpea (Vigna unguiculata(Leguminosae)). In a no-choice situation, the attractiveness of some odour sources to the parasitoid was studied in a simple diffusion olfactometer. Cox's proportional hazards model was used for data analysis. The results showed that cowpea beans were more attractive to naiveU. lariophagafemales than glass beads. Baits with host eggs were more attractive than baits without eggs. Experienced females did not perform any better than naive ones. The relationship between the inclination to fly of the parasitoids, and the baits used, was difficult to interpret. Changes in searching activity between the different weeks of experimentation were observed. Only a small part of this variation could be explained by (absolute) changes in barometric pressure.
Ovipositional behaviour of Macrolophus caliginosus (Heteroptera: Miridae) on tobacco leaves
Authors: Ferran A. , Rortais A. , Malausa J.C. , Gambier J. , Lambin M.
Published: July 2009

The ovipositional behaviour of the mirid predator Macrolophus caliginosus Wagner, a potential biological control agent of glasshouse pests, was studied in detail using a modified video camera technique. In the laboratory, females laid their eggs in the leaves of tobacco plants. They remained generally motionless on the main veins of the leaves, raised their body, folded the rostrum towards the thorax and extended their ovipositor when selecting a site in which to oviposit. The ovipositor was inserted into the plant tissue by a downward and forward thrust of the body and contractions of the abdominal muscles. After a period of immobility, the ovipositor was retracted and the insect's body and organs returned to their initial positions. This behaviour was preceded and followed by extensive rostral exploration of the oviposition site. In most females the same area was explored before and after egg-laying and the ovipositor was inserted approximately in the middle of the selected area. The sequence and pattern of ovipositional behaviour varied between females.
Comparative developmental biology of populations of three European and one North American Eubazus spp. (Hymenoptera: Braconidae), parasitoids of Pissodes spp. weevils (Coleoptera: Curculionidae)
Authors: Kenis M. , Hulme M.A. , Mills N.J.
Published: July 2009

Observations were made on the developmental responses of the North American braconid species, Eubazus crassigaster, a parasitoid of the white pine weevil, Pissoles strobi, and three European congeneric species, E. semirugosus, E. robustus, and Eubazus sp. Several populations of Eubazus spp. were compared in their phenology in the laboratory and under natural conditions. When reared in the laboratory on non-diapausing Pissodes castaneus, mountain populations of E. semirugosus and E. robustus entered into an obligatory diapause in the host larva, whereas all the other populations tested developed continuously. Diapausing larvae continued their development only after having experienced at least three months at 2°C. Non-diapausing populations of Eubazus spp. significantly differed in the duration of pre-imaginal development, with E. semirugosus being the fastest developing species and E. robustus the slowest. Outdoor rearings of Eubazus spp. on P. castaneus showed that E. crassigaster, Eubazus sp. and the lowland biotype of E. semirugosus emerged in the year of oviposition if this occurred early enough to allow parasitoid development. In contrast, a majority of E. robustus individuals overwintered in the host larvae, regardless of the oviposition date. The diapausing, mountain biotype of E. semirugosus is considered as the most promising candidate for control of P. strobi in Canada, because it is likely to be better adapted to the life cycle of the target host than the other Eubazus spp., including the native E. crassigaster.
Behaviour of Myzus persicae (Sulz.) on tobacco III. Choice by alatae of sites for feeding and larviposition on leaves and artificial substrates of differing nutrient status
Authors: Legge J. B. B. , Palmer Judith
Published: July 2009

In field experiments carried out at Kutsaga, Rhodesia, tobacco plants that had received high or low amounts of nitrogen, in addition to a basic dressing, were examined over five-week periods for the presence of alates and newly; deposited nymphs of Myzus persicae (Sulz.). It was found that settling and larviposition were reduced as a result of nitrogen deficiency in the plants, I apparently due more to some effect associated with slower plant growth than to reduced nutritional suitability. Washing with water enhanced the attractiveness of leaves in laboratory flight-chamber tests with alatae, suggesting the presence of a repellent substance on unwashed leaves. In flight-chamber tests with alatae, and choice-chamber tests with apterae, using artificial leaves made by forming Parafilm sachets on yellow Perspex discs, it was found that larviposition and nutritional suitability were related, and that both were affected by altering the balance of nutrients in the sachets, in the absence of any stimuli on the surfaces of the membranes.
Observations on the control of the coffee berry borer, Hypothenemus hampei (Ferr.), with endosulfan in Uganda
Authors: Ingram W. R.
Published: July 2009

Three field trials with endosulfan against coffee berry borer, Hypothenemus hampei (Ferr.), on both Coffea arabica and C. canephora are described. The insecticide was applied from motorized knapsack sprayers at 20 gal. per acre of an emulsified solution containing 0.2 per cent, active ingredient to the branches bearing the crop.

In two trials endosulfan applied twice at 21-day intervals significantly reduced the numbers of cherries containing living borers and the percentage of damaged cherries at the first pick. In the third trial a single application of endosulfan proved to be as effective as the double one. Increases in yield could not be detected. It was shown, by allowing insects to emerge from caged samples of cherries taken when picking began, that endosulfan did not affect the host/parasite ratio of either H. hampei or Geratitis coffeae (Bez.), nor did it increase the numbers of berry-boring caterpillars.

No off-flavours following treatment could be detected in liquoring trials of robusta coffee beans that were dry processed or pulped and washed.

Laboratory experiments in which adults of H. hampei were exposed above, but out of contact with, filter papers that had been dipped in an emulsified solution containing 0·2 per cent, endosulfan showed that it was acting at least as a partial fumigant and was more effective at 30°C. than at room temperature (21°C); spraying should thus preferably be carried out on warm, sunny days. In view of these findings, and as it is relatively non-toxic, endosulfan is recommended for control of H. hampei in Uganda when heavy attacks occur.
Oviposition and fertility and their relation to copulation in Melanoplus sanguinipes (F.)
Authors: Smith D. S.
Published: July 2009

In the laboratory, at a temperature of 30 ± 1°C. and 45 ± 2 per cent, relative humidity, the number of fertile eggs produced by females of Melanoplus sanguinipes (F.) that had copulated once and had then been reared alone in a cage was not significantly smaller than that produced by control pairs of males and females of this grasshopper. The solitary females laid more eggs than did the control females, but the eggs had a significantly lower percentage fertility. They also lived significantly longer, and one female produced eggs over a period of 140 days. Solitary and control females laid the same number of pods per day but the number of eggs per pod gradually decreased after the first two months of egg laying, particularly in the case of the control females, reflecting a decrease with time in the number of functional ovarioles.
Shot-hole borer (Xyleborus fornicatus Eichh.) of tea in Ceylon II.—The effect of chemical control on the yield and manurial response of tea
Authors: Cranham J. E. , Kanapathapillai P. , Kathiravetpillai A.
Published: July 2009

In 1960–65, six field trials were carried out on tea estates in Ceylon to assess the effect on yield, and on the response of the crop to fertilizer, of dieldrin sprays applied after pruning to control shot-hole borer (Xyleborus fornicatus Eichh.). Periodic sampling was carried out to assess the numbers of borers and their galleries. Yields were recorded by weekly or fortnightly weighings of the green leaf plucked, over pruning cycles of two to four years.

The pattern of the yield increases on the sprayed plots was related to the difference in attack between the sprayed and unsprayed plots. Increases were, in general, small in the first year and much larger in the second year, reaching peak values of 32–58 per cent. (on the yields of successive three-monthly periods recorded) in the late second year, and declining thereafter through the third year as the difference in attack declined. Over the first two years there were marked yield increases in eight of the nine pruning cycles, and these ranged from 11·7 per cent, to 26·3 per cent. There was significant regression (P<0·001) of the percentage increase in yield on the maximum difference in gallery counts. Yield increases in the third year of pruning cycles were also considerable and the results evidence a prolonged effect of the heavy borer attack occurring in the second year.

In one trial there was a significant interaction between the effects of dieldrin spraying and of nitrogen supplied. Control of the borer greatly improved the crop response to nitrogen. Nitrogen application increased the yield but resulted also in a proportionately larger loss of crop from borer attack. There was a small but significant increase in the number of borer galleries on the plots receiving nitrogen.

The evidence on the size and pattern of crop losses caused by the borer suggests that these occur both from shoot breakages and from the direct effect of galleries on the growth of stems.

The significance of the results in relation to estate practice, and the economics of spraying, are briefly discussed.
Field Trials of the Control of Glossina palpalis (R.-D.) by Obstructive Clearing
Authors: Kernaghan R. J. , Davies J. B.
Published: July 2009

Two field trials of obstruction (‘ obstructive clearing ’) as a means of control of Glossina palpalis (R.-D.) in locations representative of the Northern and Southern Guinea Savannah zones of Nigeria, are described.

In neither case was complete eradication achieved, pockets of G. palpalis remaining from the beginning at certain points on the main stream. Greater success was obtained in the smaller tributaries, which lent themselves more to obstruction. There was little penetration of G. palpalis for any great distance into obstructed reaches from natural ‘ reservoirs ’ left abutting on to the obstruction, but a trial of the ‘ protective ’ value of obstruction failed, owing to complete penetration in some strength of 300 yd. of obstructed stream on either side of the point to be protected. In neither case was immigration of flies from elsewhere into the trial areas an important factor. Although, at first, the surviving fly population was very localised, there were later indications that dispersal was beginning to take place.

Some accidents which may happen to obstruction are described, with their effects on its ultimate appearance. Consequent to these, a number of factors which limit the wide application of obstruction are stated. The more important of these are: the dimensions of the river-bed, which may be too large to permit of successful obstruction; the presence of wide swampy forest through which G. palpalis ranges freely; alternatively, the presence of shallow rocky stretches with low eroded banks that may be devoid of all but certain characteristic trees, where adequate obstruction is impossible; the rate of run-off of water in the catchment area, rapid run-off leading to spates which disrupt the obstruction; human interference with the obstruction in quest of firewood.

No technical difficulties were encountered in carrying out obstruction, and costs were from 40 to 50 per cent, cheaper than comparable partial clearing.

Considering the subsequent appearance of originally obstructed stream, and its frequent resemblance to partial clearing, the suggestion of ‘ destructive ’ clearing is put forward, in which the top canopy would be destroyed, but no effort made either to create obstruction or to clear away the fallen trees. Instead, reliance would be placed on the action of the various agencies encountered in these trials, which brought about the disruption of the obstruction, to produce the desired end-result.

It is concluded that successful obstruction depends too much on specialised conditions, difficult to fulfil in large-scale tsetse control schemes, and that it is unlikely to become a normal method of control of G. palpalis in the savannah zones of Nigeria.
Investigations on Heliothis armigera (HB.) in Uganda
Authors: Coaker T. H.
Published: July 2009

A survey of the populations of eggs and larvae of Heliothis armigera (Hb.) was made on the Cotton Research Station, Namulonge, in Buganda Province, Uganda, over the four-year period, 1954–57 inclusive, on cotton, maize, groundnuts, beans and, in one year, sunflower. The populations encountered were low in comparison with some other cotton areas in Africa. The oviposition rate on each crop closely followed the flowering cycle, and there was no indication of the population from one crop influencing that on a subsequent crop, even when their flowering cycles overlapped. Under the normal crop sequence there is a sufficient gap between the attractive phases of successive crops to cause dispersal, possibly to wild host-plants, of the moths emerging from pupae bred in the preceding crop.

The variation in population from year to year on a given crop was no greater than that between different localities in any one season. Maize and sunflower did not prove successful when tested as trap crops grown adjacent to cotton.

Earias spp. and Argyroploce leucotreta Meyr. were less abundant than Heliothis and together constituted only 27 per cent, of the total population of Lepidopterous larvae on cotton.

A method is described for breeding H. armigera, in the laboratory, in which the mean duration of the various stages was: egg, 4 days; larva, 24·8 days; pupa, 22·9 days; preoviposition period, 3·1 days; and oviposition period, 10·4 days. The mean number of eggs laid per female was 751·6, of which 71·4 per cent, hatched. Larval diets consisting of differing species and parts of food-plants caused significant differences in larval and pupal periods, the former being least (21·8 days) on maize silks and greatest (33·6 days) on sunflower corolla and receptacle, and the latter least (19·7 days) after larval feeding on three-week-old maize cobs and greatest (26 days) after seven-week-old cotton bolls. Pupae developing from larvae collected from the field did not exhibit any diapause or resting stage.

Two egg parasites and 15 larval parasites (three of which were probably secondary) were bred from material of H. armigera collected in the field, but the degree of parasitism remained low throughout the year. A nuclear polyhedral virus disease of the larvae was also recorded.

It is concluded that under the climatic conditions encountered, H. armigera is active throughout the year because wild or cultivated food-plants are always available and no resting stage of the insect is induced; this continuous activity is accompanied by biologically controlling factors that maintain populations stable at a relatively low level.