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BACKGROUND The reliance on and extensive use of pyrethroid insecticides have led to pyrethroid resistance in pollen beetle (Meligethes aeneus). Widespread adoption of best practice in pollen beetle management is therefore needed. Decision support systems (DSSs) that identify the risk period(s) for pest migration can help to target monitoring and control efforts, but they must be accurate and labour efficient to gain the support of growers. Weather data and the phenology of pollen beetles in 44 winter oilseed rape crops across England over 4 years were used to compare the performance of two risk management tools: the DSS proPlant expert, which predicts migration risk according to a phenological model and local weather data, and ‘rule-based advice’, which depends on crop growth stage and a temperature threshold. RESULTS Both risk management tools were effective in prompting monitoring that would detect breaches of various control thresholds. However, the DSS more accurately predicted migration start and advised significantly fewer days of migration risk, consultation days and monitoring than did rule-based advice. CONCLUSION The proPlant expert DSS reliably models pollen beetle phenology. Use of such a DSS can focus monitoring effort to when it is most needed, facilitate the practical use of thresholds and help to prevent unnecessary insecticide applications and the development of insecticide resistance. © 2015 Rothamsted Research Ltd. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

BACKGROUND The reliance on and extensive use of pyrethroid insecticides have led to pyrethroid resistance in pollen beetle (Meligethes aeneus). Widespread adoption of best practice in pollen beetle management is therefore needed. Decision support systems (DSSs) that identify the risk period(s) for pest migration can help to target monitoring and control efforts, but they must be accurate and labour efficient to gain the support of growers. Weather data and the phenology of pollen beetles in 44 winter oilseed rape crops across England over 4 years were used to compare the performance of two risk management tools: the DSS proPlant expert, which predicts migration risk according to a phenological model and local weather data, and ‘rule‐based advice’, which depends on crop growth stage and a temperature threshold. RESULTS Both risk management tools were effective in prompting monitoring that would detect breaches of various control thresholds. However, the DSS more accurately predicted migration start and advised significantly fewer days of migration risk, consultation days and monitoring than did rule‐based advice. CONCLUSION The proPlant expert DSS reliably models pollen beetle phenology. Use of such a DSS can focus monitoring effort to when it is most needed, facilitate the practical use of thresholds and help to prevent unnecessary insecticide applications and the development of insecticide resistance. © 2015 Rothamsted Research Ltd. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

BACKGROUNDPollen beetle (Meligethes aeneus F.) management in oilseed rape (Brassica napus L.) has become an urgent issue in the light of insecticide resistance. Risk prediction advice has relied upon flight temperature thresholds, while risk assessment uses simple economic thresholds. However, there is variation in the reported temperature of migration, and economic thresholds vary widely across Europe, probably owing to climatic factors interacting with beetle activity and plant compensation for damage. The effect of temperature on flight, feeding and oviposition activity of M. aeneus was examined in controlled conditions. RESULTSEscape from a release vial was taken as evidence of flight and was supported by video observations. The propensity to fly followed a sigmoid temperature-response curve between 6 and 23 degrees C; the 10, 25 and 50% flight temperature thresholds were 12.0-12.5 degrees C, 13.6-14.2 degrees C and 15.5-16.2 degrees C, respectively. Thresholds were slightly higher in the second of two flight bioassays, suggesting an effect of beetle age. Strong positive relationships were found between temperature (6-20 degrees C) and the rates of feeding and oviposition on flower buds of oilseed rape. CONCLUSIONThese temperature relationships could be used to improve M. aeneus migration risk assessment, refine weather-based decision support systems and modulate damage thresholds according to rates of bud damage. (c) 2014 Society of Chemical Industry

The within-field spatio-temporal distributions and relationships of two pest insects with stem-mining larvae, Psylliodes chrysocephala (L.) (Coleoptera: Chrysomelidae) and Ceutorhynchus pallidactylus (Marsham) (Coleoptera: Curculionidae), and their larval endoparasitoids, Tersilochus microgaster (Szepligeti) and Tersilochus obscurator Aubert (Hymenoptera: Ichneumonidae), respectively, were studied in a crop of winter oilseed rape [Brassica napus L. (Brassicaceae)]. The insects were sampled, at different life stages, at 40 spatially referenced points within the oilseed rape in 1998-99 and in the following crop of winter wheat. Distributions were analysed and compared using SADIE (Spatial Analysis by Distance IndicEs) and by tests of edge distribution. Tersilochus microgaster emerged from overwintering by the end of March and T. obscurator from mid April to mid May 2000. Tersilochus microgaster parasitized 10.8% of P. chrysocephala larvae, peak parasitism occurring in May. The distribution of each species was patchy and irregular. Psylliodes chrysocephala and its parasitoid were closely associated, but new generation C. pallidactylus and T. obscurator were less so, probably because of host mortality caused by the parasitoid. The two host-parasitoid pairs showed distributions that were polarized with respect to each other. The genesis of these spatial patterns is discussed in relation to the influence of wind direction, plant size, and interspecific interactions. The potential of these parasitoids as biocontrol agents in integrated pest management is discussed. Opportunities for conservation biocontrol in oilseed rape offered by spatio-temporal targeting of insecticides to avoid parasitoids and by reduced soil tillage are examined.

Semi-field-scale arrays of oilseed rape (Brassica napus L.) (Brassicaceae) plants were used to observe the development of distributions of pollen beetles (Meligethes aeneus Fabricius) (Coleoptera: Nitidulidae) in a simulated trap crop system where inflorescence growth stage alone was used to manipulate the pest. Over two successive years, pairs of 1 m spaced square arrays of 100 glasshouse-grown plants were placed 40 m apart in the field in May, and were subject to natural infestation by pollen beetles. The test plot of each pair had a simulated trap crop, with an outer row of plants at early flowering stage intended to protect more susceptible inner plants at late bud stage, and the control plot had all plants at the late-bud stage, simulating a standard crop situation. Pollen beetles were counted daily on each plant for 10-13 days. The spatio-temporal development of plot infestation was analysed in relation to the distribution of racemes in bud and raceme in flowers using Spatial Analysis by Distance IndicEs (SADIE), and tests of edge and centre distribution. Inflorescence growth stage characteristics were shown to be important in determining the spatial distributions of pollen beetles. In control plots, the numbers of racemes in bud and in flower were never edge or centre distributed. In test plots, racemes in flower were always edge distributed, and racemes in bud began edge distributed and became centre distributed. Pollen beetle numbers were usually spatially associated with the abundance of racemes in bud and/or in flower. In control plots, pollen beetles were neither edge nor centre distributed, but in test plots they maintained a significant edge distribution for 7-10 days. At the end of the experiments, females were more centre distributed in the test plots than males, and were more closely associated with racemes with buds, whereas males were more associated with racemes with flowers. In early flowering stage plants, the number of racemes in flowers were a good indicator of the abundance of racemes in buds, but this relationship was lost as flowering progressed. Although flowering racemes provide strong cues for immigrating pollen beetles, the abundance of buds may be a more important determinant of residence time, particularly for females, and is therefore a critical determinant of trap crop effectiveness.

The definitive version is available at www.blackwell-synergy.com Copyright Blackwell Publishing [Full text of this article is not available in the UHRA]

Insect pests, plant growth and plant yield in a crop of winter oilseed rape ( Brassica napus L.) were studied to assess the potential value of spatial information in integrated pest management for this crop. Ceutorhynchus assimilis Payk., Ceutorhynchus pallidactylus (Marsh.), Meligethes aeneus (Fab.) and Dasineura brassicae Winn. were sampled from the nodes of a rectangular grid across the crop. Their spatial distributions were mapped, analysed and compared using Spatial Analysis by Distance IndicEs (SADIE). The relationships between the distributions of insects, plant growth and yield were assessed using regression techniques. The distributions of C. assimilis , C. pallidactylus and M. aeneus were complex with differing irregular patterns of aggregation, whereas D. brassicae was edge-distributed. Stem injury, chiefly caused by larval Psylliodes chrysocephala L., was associated with significant yield loss and the spatial distribution of stem injury was reflected in the distribution of oil yield. The distribution of larval M. aeneus was dissociated from that of pods which shed their seed before harvest. Spatial heterogeneity in plant maturation as a result of infestation could delay the choice of harvest date beyond the optimum to prevent seed loss from less injured plants. Some of the variability (21–31%) in insect numbers within the crop was explained by variation in plant density and in growth stage at mid-flowering. The spatial ecology of these pests is discussed in terms of the roles of environmental factors, behavioural responses and the implications of spatial patterns for yield loss and for developing sustainable integrated crop protection. The data indicate that decision support systems should use sampling strategies which incorporate spatial information to model crop loss more accurately and that there may be potential for spatially targeted applications of insecticide to optimise the influence of biocontrol agents in oilseed rape.

The brassica pod midge (Dasineura brassicae) is an important and widespread pest of winter and spring oilseed rape throughout Europe. Pods infested by D brassicae larvae split prematurely, releasing seeds, and the larvae drop to the soil into which they burrow to pupate. At this stage in its lifecycle D brassicae is potentially vulnerable to predation by carabid beetles foraging on the soil surface. This is the first study in the UK to focus on carabid beetles as predators of D brassicae in the oilseed rape crop. The spatio-temporal distributions of larvae of D brassicae dropping to the soil from the crop canopy and of adult carabid beetles active on the soil surface were analysed in two consecutive years. Insect samples were collected from spatially referenced sampling points across each crop. Counts of insects were mapped and analysed, and the degree of spatial association between predator and prey determined using Spatial Analysis by Distance Indices (SADIE). Carabid species abundant and active during peak drop of first generation D brassicae larvae included Agonum dorsale, Amara similata, Harpalus rufipes and Nebria brevicollis. The larvae of D brassicae had a marked edge distribution within the crop. SADIE analysis revealed significant spatial association between larvae of D brassicae and adult H rufipes (P

Following oviposition into a pod of oilseed rape (Brassica napus), the female cabbage seed weevil (Ceutorhynchus assimilis) marks the pod with oviposition-deterring pheromone (ODP) by brushing it with her eighth abdominal tergite. On an unmarked pod, oviposition site selection was always accompanied by intensive antennation of the pod. Females approaching a freshly ODP-marked pod brought their antennae within 1 mm of the pod but usually did not antennate it before rejecting it for oviposition. Females with the clubs of their antennae amputated continued to discriminate pods from stems or petioles as oviposition sites but showed no behavioral response to ODP. Extracts of volatiles air-entrained from ovipositing weevils failed to inhibit oviposition. Air passed over a behaviorally active extract of ODP did not elicit a detectable electroantennogram response. By contrast, when presented as a gustatory stimulus to the sensilla chaetica of the antennal club, a behaviorally active extract of ODP from postdiapause, gravid females elicited a strong electrophysiological response. This response usually involved more than one cell and displayed a phasic–tonic time course over the recording period of 10 sec. Extract from prediapause (and hence sexually immature) females elicited neither behavioral nor electrophysiological (contact) responses. Thus the ODP of the cabbage seed weevil is sensed primarily by contact chemoreception at the sensilla chaetica of the antennae, and the electrophysiological responses recorded from these gustatory sensilla are of value as the basis of a bioassay to assist identification of the active constituent(s) of the pheromone.

We present a case of vertical gaze palsy in a 13-year-old girl caused by underlying infective endocarditis, secondary to an infected navel piercing. This case illustrates that infective endocarditis does not always present with classic signs. J Pediatr Ophthalmol Strabismus 2006;43:41-43. AUTHORS The authors are from Ninewells Hospital, Dundee, Scotland. Originally submitted March 30, 2004. Accepted for publication November 19, 2004. Address reprint requests to Dr. Andrew Ferguson, Department of Ophthalmology, Ninewells Hospital, Dundee DD1 9SY, Scotland. Presented in part at the Annual Meeting of the Scottish Ophthalmological Club; October 3, 2003; Erskine, Scotland.

Pests were monitored on linseed crops in Hertfordshire, Cambridgeshire and Bedfordshire from 1987 to 1990. Adult flea beetles (Aphthona euphorbias and Longitarsus parvulus) caused severe injury to seedlings; their numbers have markedly increased since 1990 and they are now important pests of linseed in the UK. Two generations of Thrips angusticeps bred on linseed, causing damage to growing points and flower buds and approximately 14% yield loss to a crop in Hampshire. Mirids, mostly Calocoris norvegiens and Lygus rugulipennis, caused injury similar to that caused by thrips. Mirids were more abundant close to field boundaries with woody plants, whereas thrips were fewer at these boundaries and rather evenly distributed within the rest of the field. Few other insects and no aphid colonies were found. Experiments with insecticide treatments provided evidence of compensation for insect injury by additional flower production.

Pests were monitored on plots of Lupinus albus and other Lupinus species in Hertfordshire and Bedfordshire between 1986 and 1990. Slug damage was common in winter on autumn-sown plants. Sitona lineatus (Curculionidae) caused some feeding damage but larvae were not found. Delia platura (Anthomyidae) larvae severely damaged shoots and hypocotyls of late spring-sown L. albus plants in 1986 and probably injured autumn-sown seedlings. In autumn-sown L. albus following a barley ( Hordeum sp.) crop, Thrips angusticeps seriously injured leaves and flower buds in April and May. The aphid Macrosiphum albifrons was present each year and probably overwintered on autumn-sown L. albus in 1989/1990. Its distribution was patchy and injury was most severe in flowering plants. M. albifrons is a vector for bean yellow mosaic virus which was found in L. albus in Norfolk. Twelve other aphid species were found on lupin, five forming colonies; Aphis craccivora and Macrosiphum euphorbiae were the most abundant. Damage by lepidopteran larvae was slight; the tortricids Cnephasia asseclana and C. pasiuana were most common. Mirids, cicadellids and leaf miners caused negligible injury. Pollen beetles ( Meligethes spp.) were found in flowers and mature flower buds. No significant beneficial effects of combined insecticide and fungicide treatments were measured. Macrosiphum albifrons , slugs, T. angusticeps and D. platura probably have the greatest pest potential.

Good co-incidence in time and space between parasitoids and the pests they attack is essential for effective biocontrol. The six major pests of oilseed rape in Europe migrate to the crop in succession, attacking the crop at various growth stages and damaging different parts of the plant. Research on the phenologies and within-field spatial distributions of the pests and their key parasitoids on oilseed rape crops is reviewed. Pest distributions are non-uniform, with differing irregular patterns of aggregation, often edge-distributed. Parasitoid distributions do not necessarily completely reflect those of the host stage they attack. Crop and environmental factors affecting these distributions are discussed. The spatio-temporal distributions have implications for biocontrol-based integrated management of the pests. These include accurate sampling for pest monitoring, the temporal and spatial targeting of pests with insecticide to avoid killing parasitoids and strategies for manipulating pest and parasitoid distributions through the siting, layout and surround of the crop to enhance parasitoid populations and increase their effectiveness.

Ground beetles or carabids are amongst the most abundant invertebrate predators in fields of oilseed rape in Europe. The immature stages of the six major pests of oilseed rape i.e., cabbage stem flea beetle, pollen beetle, cabbage seed weevil, cabbage stem weevil, rape stem weevil and brassica pod midge, are vulnerable to predation by carabids when they are in or on the soil from mid-September to mid-July. About 42 species of carabid are common in rape fields. The community composition varies between countries, between spring and winter crops and with crop management, as species differ in distribution and habitat requirements. The ten most widespread and dominant species are A. similata, Anchomenus dorsalis, Bembidion lampros, Harpalus affinis, Harpalus rufipes, Loricera pilicornis, Nebria brevicollis, Poecilus cupreus, Pterostichus melanarius and Trechus quadristriatus. A field-scale study found within-field spatio-temporal coincidence of T. quadristriatus and Pterostichus madidus with cabbage stem flea beetle eggs, of A. similata, N. brevicollis and Asaphidion spp. with pollen beetle larvae, and of A. dorsalis with larvae of cabbage stem weevil, cabbage seed weevil and brassica pod midge. Carabid within-field distributions are influenced by their life cycles, habitat preferences, mobility and food availability. Evidence of predation from analysis of gut contents of field-collected individuals and laboratory feeding trials is reviewed in relation to carabid functional morphology, prey size and diel periodicity of activity. Feeding trials suggest that Clivina fossor also has potential as a predator of oilseed rape pests. The implications for biocontrol-based integrated pest management are discussed.

The six major pests of oilseed rape, namely the cabbage stem flea beetle, the cabbage stem weevil, the rape stem weevil, the pollen beetle, the cabbage seed weevil and the brassica pod midge, are reported to host at least 80 species of hymenopteran parasitoids. Of these, 12 key species are widespread and abundant on oilseed rape crops throughout Europe; these species are important for conservation biocontrol of the pests on winter rape. This guide aims to help in their identification. It collates information from previously published keys, other literature and recent extensive examination of specimens and highlights selected key features of relevant taxa from superfamily to species. It is liberally illustrated with figures, newly-drafted and redrawn and/or modified from published literature. A glossary of terms is provided.

The behaviour of queen and worker honeybees (Apis melliferaL.) was observed using small colonies in observation hives. Workers paid more attention to queens which had been mated for 2 months or more than to those which were newly mated; virgin queens received least attention. Queens received most attention when they were stationary and least when they were walking over the comb; virgin queens were most active. Queen cells had as many attendants as virgin queens and queen larvae were inspected almost continuously. The queen pheromone component 9–oxo-trans-2–decenoic acid stimulated ‘court’ behaviour when presented on small polyethylene blocks, but workers responded aggressively to complete extracts of queens' heads. Both the heads and abdomens of mated queens received much attention from court workers but the abdomens were palpated by more workers for longer and were licked much more. The queens' thoraces were least attended. Abdominal tergites posterior to tergite glands were licked for longer than those anterior to the glands. Only worker bees very near to the queen reacted to her and joined her ‘court’. No evidence was found of a diel periodicity in the behaviour of a queen or her ‘court’. During the winter the queen's court was smaller than in summer and she walked less and laid fewer eggs. When colonies were fed with sucrose syrup in winter, their queens laid more eggs and workers reared more brood but there was no change in the attention received by the queens. The implications of these findings for the secretion and distribution of queen pheromones are discussed.

The decision to repair an orbital blow-out fracture depends on several factors, but evidence for the optimum timing of surgery is not clear. We retrospectively studied all patients with orbital injuries who were referred to the eye department at a Scottish teaching hospital over a 10-year period from 1997 to 2006. We aimed to document the incidence and pattern of disturbances of ocular motility after blow-out fractures, and identify the rates of early and late resolution of these deficits, both spontaneously and after surgical repair. We found that most patients with blow-out fractures had a motility defect for an acute phase; approximately one third of which resolved spontaneously within 2 weeks. Recovery of motility after orbital surgery occurred in less than half the patients, and was not immediate. Continuing recovery also occurred in those who did not undergo surgery. Entrapment of muscle or tissue is not the only cause of motility disturbance after blow-out fractures, and orbital surgery is only one aspect of management in those patients with persistent motility defects.

1 The spatio-temporal distributions of predatory carabid beetles (Coleoptera: Carabidae) and their potential prey, the larvae of three coleopterous pests, Meligethes aeneus (Fabricius) and Ceutorhynchus spp. [Ceutorhynchus pallidactylus (Marsham), the cabbage stem weevil, and Ceutorhynchus assimilis (Paykull), the cabbage seed weevil], were studied within a crop of winter oilseed rape. The distributions of Collembola were recorded as potential alternative prey. Insect distributions were analysed and compared using Spatial Analysis by Distance Indices. 2 Mature larvae of the pests dropped from the crop canopy to the soil for pupation in temporal succession from May to early July. Their distributions within the crop were irregular and differed with species. 3 Adults of seven species or genera of carabid were abundant and active within the crop during May and June: Nebria brevicollis (Fabricius), Anchomenus dorsalis (Pontoppidan), Loricera pilicornis (Fabricius), Amara similata (Gyllenhal), Asaphidion spp., Pterostichus madidus (Fabricius) and Pterostichus melanarius (Illiger). 4 During May, N. brevicollis was spatially associated with peak numbers of M. aeneus larvae and with Collembola. Anchomenus dorsalis was spatially associated with Ceutorhynchus spp. larvae during two peaks in the abundance of the latter in early and late June. Nebria brevicollis and A. dorsalis coincided in both time and space with larvae of the three coleopterous pests when they were most vulnerable to predation by epigeal predators and are therefore good candidates for conservation biocontrol. 5 The importance of carabid beeetles in the natural enemy complex in winter oilseed rape and their potential for biocontrol of spring and summer pests are discussed in relation to husbandry practices for the crop and its adjacent areas which could be manipulated to promote carabid survival for integrated pest management.

Summary — A simple new technique for testing worker honeybees’ ability to distinguish between honeybee queens is presented. Two queens were caged separately with groups of young sibling workers which were the daughters of another queen. The cages were exposed to the same environmental odours for 10 days. When placed in the test apparatus and given a choice of both queens, workers segregated towards the queen with which they had been caged. This provides further evidence that the distinctive odour of an individual queen is probably partly inherited and is learned by workers. The nature and functioning of queen odours are discussed. Apis mellifera / queen recognition / odour / genetic component

Tersilochus obscuratorAubert andTersilochus microgaster(Szépligeti) are larval endoparasitoids of economically-important stem-mining pests of winter oilseed rape (Brassica napusL.) in Europe. They are difficult to separate morphologically. Their hosts areCeutorhynchus pallidactylus(Marsham) andPsylliodes chrysocephalaLinnaeus, respectively. The parasitoids' taxonomic status, identification, host range and phenology were studied using genetic, morphometric and ecological data. The study used 527 female parasitoids from the UK and Germany, either field-collected in emergence traps or reared from field-collected host larvae. Two morphometric characters, the ovipositor sheath to first metasomal tergite ratio and the percentage of the mesopleuron spanned by the sternaulus, were measured. A 440 bp section of mitochondrial DNA cytochrome oxidase subunit I (COI) gene was sequenced from 35 parasitoids reared fromC. pallidactylus, 20 reared fromP. chrysocephalaand individuals from two outgroups,Tersilochus heterocerusThomson andPhradis interstitialisThomson. Distinct and invariable COI sequences corresponded exclusively to each parasitoid group, confirming thatT. obscuratorandT. microgasterare discrete species. Measurements of host-reared and COI-sequenced specimens indicated that the ranges of both morphometric characters overlapped between species. Using these ranges as criteria, all but 3.6% of UK specimens and 2% of German specimens were identifiable to species without reference to host or phenology. There were differences in emergence phenology in the UK, adultT. microgasteremerging from winter diapause by 29 March 2000,T. obscuratoremerging between 12 April and 24 May 2000. The value of molecular techniques in the identification of closely-related parasitoid species is discussed.

After laying an egg into a pod of Brassica napus, the female cabbage seed weevil, Ceutorhynchus assimilis, brushes the caudal setae of the eighth abdominal tergite (VIII UT) on the host pod as she walks along it, depositing oviposition-deterring pheromone (ODP). The VIII UT is periodically extended and withdrawn, thus repeatedly rubbing against the posterior fold of the seventh urotergite (VII UT) which bears the individual outlets of glandular epidermal cells. In post-diapause, sexually mature, gravid (i.e. oviferous) females (virgin or mated) the cells of this VII UT gland were hypertrophic, showing intense secretory activity. Extracts of VII UT from these individuals elicited strong electrophysiological responses from antennal club gustatory sensilla and deterred oviposition. In pre-diapause (sexually immature) females, the cells of the VII UT gland were neither hypertrophic nor active and an extract of their VII UT elicited no significant electrophysiological or behavioural response. Extract of female rectum was a less potent oviposition deterrent than VII UT extract and elicited an electrophysiological response similar to male rectum extract. An extract of ovarian calyces and ovaries elicited no behavioural response. We conclude that ODP is secreted by the epidermal cells of the VII UT posterior fold.

The spatio-temporal distribution of Ceutorhynchus assimilis Payk. (Coleoptera: Curculionidae) adults caught in a rectangular grid of flight traps in a crop of winter oilseed rape (Brassica napus L.) was mapped and was analysed using Spatial Analysis by Distance IndicEs (SADIE). Their distribution was compared to that of their larvae and that of their parasitoid Trichomalus perfectus (Walker) (Hymenoptera: Pteromalidae) in pods. The distribution of immigrating C. assimilis adults was consistent with their arrival at the crop boundaries and movement within the crop towards its centre. Adult C. assimilis were aggregated at all times, invasion being on two fronts, leading to the formation of two major clusters within the crop. Large areas of the crop remained relatively unpopulated. During the emigration phase, numbers declined simultaneously in all parts of the crop. The distributions of adult and larval C. assimilis and of larval T. perfectus were spatially associated. The distribution of the parasitoid did not show a density dependent relationship with that of its host. We discuss the movements of insects which underlie their population distributions, the value of integrating spatial information into improved management strategies for C. assimilis and the potential for the spatial targeting of insecticides to reduce the amount applied and to conserve T. perfectus.

SUMMARYEffects of diseases on growth and yield of linseed (cv. Antares) were assessed by controlling diseases with fungicide treatments in field experiments at Rothamsted from 1988 to 1990. Fungicide seed treatments decreased the incidence of Alternaria lesions on cotyledons and stem bases of emerging seedlings in 1989 but decreased emergence in 1990. The incidenceof leaf browning, associated with Alternaria spp. and Botrytis cinerea, was less in 1989 and 1990 than in 1988 when the period, in July, between flowering and harvest was wet, but the incidence of powdery mildew was greater in 1989 and 1990 than in 1988. Fungicide spraysdecreased leaf browning in 1988 and powdery mildew in 1990. In 1988 there were more capsules per plant and the crop was taller than in either 1990 or 1989, when July and August were hot withperiods of dry weather. The incidence of plants with dark brown stems, associated with Verticillhun dahliae, was greater in 1989 and 1990 than in 1988, but was not greatly affected byfungicide treatments. The incidence of Alternaria linicola on sepals, capsule cases and seed from capsules sampled before harvest was decreased by fungicide treatments. Other fungi isolated from these tissues included A. alternata, A. infectoria, B. cinerea, Fusarium spp. and V. dahliae. Yields of grain and oil were increased by fungicide treatments in all three years, but the yield increases were greatest in 1988 when fungicide treatments also increased 1000-grain weight. The incidence of fungi on the harvested seed was not greatly affected by fungicide treatments.

SUMMARYThe pollination requirements of the white lupin cultivar Vladimir were investigated in a glasshouse. Five treatments were compared in which the flowers of each plant were (i) left to autopollinate, (ii) shaken, (iii) tripped, (iv) self pollinated or (v) cross pollinated. Pollination treatments had no effect on the numbers of flowers, pods or seeds or weight of seed produced by the plants but did slightly shorten the duration of flowering, the effect being greatest when flowers were tripped or cross pollinated and least when they were shaken or self pollinated.The proportion of flowers that developed into pods differed with raceme, with secondaries producing more than tertiaries > primaries > quaternaries; the number of seeds per pod differed in the same order, but mean single-seed weight decreased on successive racemes. However, pollination treatments had no effect on the distribution of flowers, pods or seeds on the plant.This crop species is clearly highly self fertile and self pollinating and likely to yield well without insect pollination.

SUMMARYTo determine economic thresholds of pest infestation caged plots of oil-seed rape (Brassica napus L.) were infested with different populations of the seed weevil (Ceutorhynchus assimilis Payk.). Less than one seed weevil per plant resulted in pod infestation levels of seed weevil larvae that by themselves were insufficient to warrant insecticide application, but owing to secondary infestation of pod midge (Dasyneura brassicae Winn.), substantial seed loss occurred. Greater populations of seed weevil adults gave correspondingly larger levels of pod midge and diminishing yields.In commercial crops individual plants were able to compensate, and even to overcompensate for damage resulting from low levels of pest infestation, but increasing levels of infestation resulted in progressively fewer seeds per plant.The implications of the results on pest control and further research are discussed.

SummaryA volatile pheromone left at a food source by foragers induced others to alight. Pheromone from the dorsal surface of the abdomen was more effective than from the head and thorax. The response of bees to a food source with an artificial scent was increased with the addition of the forage-marking pheromone. When extracted from the substrate with dichloromethane it retained its biological activity.

SummaryCells containing honeybee larvae were isolated from contact with workers for periods from 15 min to 24 h. Those which had been isolated for up to 90 min, subsequently received more worker visits than did unisolated ones. Isolation for periods of 3 h or more led to increases in larval mortality. In one test, isolated cells which contained eggs were also visited more than unisolated controls.

SummaryA practical and effective mixture for attracting honeybees to cluster on a lure has been developed, based on a mixture of (E)-9-oxo-2-decenoic acid with some of the components of the Nasonov gland pheromone. The mixture contains no farnesol or nerol, and unpurified preparations are suitable. It is more effective than the mixture of the acid with all 7 components in equal proportions; this is in turn superior to a mixture of all components present in natural proportions.

SummaryTwenty-four chemical components from the sting apparatus and 2-heptanone from the mandibular glands of the worker honeybee (Apis mellifera L.) were tested at the hive entrance for their effect on alerting, stinging, Nasonov gland exposure, and flight activity. They were further tested at experimental food sources for their effect on foraging activity. In each bioassay, 33–66% of the components appeared to have some effect. Only 2 components, iso-pentyl acetate and 1-pentanol, elicited a response in all tests, and 4 of the less-volatile components elicited no response in any test in which they were presented. Some components elicited different responses when they were presented at different concentrations. Some components had an inhibitory effect on flight and foraging from the hive entrance, whereas others had a stimulatory effect. When presented at food sources, many components were repellent to foragers; a mixture of 2 components, n-octyl acetate and benzyl acetate, had the maximum repellent effe...

SummaryLures containing the synthetic pheromone components (E)- and (Z)-citrals, geraniol and nerolic and geranic acids made new hives, not previously occupied by honeybee colonies, more attractive to caged honeybee swarms than unbaited hives (20 out of 20 tests). The lure also made old hives, previously occupied by colonies, more attractive to caged swarms (19 out of 20 tests) and to swarms in natural conditions (12 occupied compared with none without the lure). Adding (E)-9-oxo-2-decenoic acid (part of the queen's mandibular gland pheromone) to the lure increased its attractiveness to caged swarms (20 out of 20 tests). Practical implications in beekeeping are discussed.

SummarySynthetic Nasonov pheromone lures that attract honeybee (Apis mellifera) swarms also stimulated bees to consume water, pollen substitute and sucrose syrup offered inside their hives, and water and sucrose syrup provided in the field. The possible value of this to beekeeping is discussed.

Techniques for investigating pheromones responsible for clustering in Apis mellifera are described. Stable queenless clusters were formed in response to synthetic Nasonov pheromone mixed with (E)-9-oxo-2-decenoic acid. This mixture plus the addition of (E)-9-hydroxy-2-decenoic acid was less potent in initiating cluster formation than it was without this addition, but the clusters once formed sometimes grew larger. Other unknown components from the queen's mandibular glands encouraged cluster formation.

Summary(Z)-ll-eicosen-l-ol, a recently discovered volatile component of the sting apparatus, is attractive to foragers trained to collect sugar syrup and to scout bees, but does not enhance the attractiveness of the Nasonov pheromone.

Worker bees recently denied access to their colony expose their Nasonov glands, thereby releasing pheromone, at the entrance to their hive. Odours of the following induced this response: empty comb, purified beeswax, honey, pollen, propolis, a live queen, the (E)-9-hydroxy-2-decenoic acid component of a queen's mandibular glands, live drones and workers, inert material on which workers had walked inside the hive, and synthetic Nasonov pheromone. The total odour of a foreign colony also induced worker bees to expose their Nasonov glands but was less effective than the odour of their own colony. Odours of the following were not effective: the (E)-9-oxo-2-decenoic acid component of a queen's mandibular glands, recently killed drones and workers, worker brood (eggs, larvae, pupae).

(1983). Foraging Behaviour of Honeybees on Oilseed Rape. Bee World: Vol. 64, No. 1, pp. 22-24.

Virgin queens are as effective as mated laying queens at inhibiting colonies from rearing queens but not from producing queen cell cups. Colonies without brood produce fewer queen cell cups than similar colonies that have brood. Colonies without queens forage much less and collect less pollen than with either a mated or virgin queen. Colonies with virgin queens forage as much as those with mated queens but collected less pollen.

The observations provided strong circumstantial evidence that workers in a queen's court obtain queen pheromone on their antennae, and that queen pheromone is distributed through the colony during antennal contact between workers. Workers that had just left the court of a mated or virgin queen had an increased tendency to make reciprocated antennal contacts with other workers. This tendency was reinforced when the workers concerned licked the queen in addition to palpating her with their antennae, probably because they spent longer in the court. The first workers contacted by those leaving the court also had an increased tendency to make reciprocated antennal contacts. Antennal contacts were more likely to be initiated by bees other than those from the queen's court. Workers from the court and those they first contacted, participated in food transfer more than did workers selected at random. Workers that licked a virgin queen subsequently participated in food transfer more than those that palpated her with their antennae only. Within about 5 min of leaving the court, a worker's participation in reciprocated antennal contacts and in food transfer diminished to the level of non-court workers. Workers chosen at random made more transient and non-reciprocated antennal contacts when in a colony with a mated queen than when in a colony with a virgin queen.

SummaryPossible pheromonal components identified from the sting apparatus, mandibular gland and Nasonov gland of worker honeybees (Apis mellifera) were tested in an attempt to elucidate their function. Other chemicals known to affect behaviour were also tested. The components iso-pentyl acetate and n-octyl acetate from the sting, and 2-heptanone from the mandibular glands, repelled bees and diminished Nasonov gland exposure (scenting); 1-pentanol and (Z)-ll-eicosen-1-ol from the sting diminished scenting; iso-pentyl acetate, n-butyl acetate, 2- nonanoyl and 1-pentanol, all from the sting, and 2-heptanone, released stinging. The alarm pheromones 2-heptanol and 3-octanone (from certain stingless bees and ants) inhibited scenting, and the former also repelled bees and released aggression. The chemicals iso-butyl acetate, sec-butyl acetate and n-pentyl acetate diminished scenting, and the insect repellents dimethyl phthalate and diethyl toluamide diminished stinging. Many of the chemicals from the honeybee st...

SummaryLarge populations of bees often continue to forage on oil-seed rape crops until flowering ceases. Applications of insecticide to crops in the late flowering stage could be hazardous to these bees.

Of the various components of the Nasonov pheromone, geraniol, (E)-citral and nerolic acid were the most important for inducing clustering. The presence of (Z)-citral with (E)-citral, or in a mixture of components including (E)-citral, did not diminish clustering and sometimes increased it. Geranic acid alone encouraged clustering, but was less effective with nerolic acid or the citrals. Nerol and (E, E)-farnesol had little obvious influence on clustering. A 1:1:1 mixture of geraniol + nerolic acid + (E)- and (Z)-citrals was as effective as a mixture of all the seven components in equal proportions, which was in turn as effective as a mixture containing the components in the proportions present naturally in the Nasonov gland.

Immediately after visiting cells containing immature queens, workers of Apis mellifera L. were observed to engage in prolonged cleaning, particularly of their tongues when they had visited larvae, and of their antennae when they had visited pupae. Thereafter other workers usually initiated and made antennal contacts with them. During such antennal contact the bee that had visited the queen larva often donated food. The implication of these findings on the distribution of pheromone produced by immature queens is discussed. Workers were stimulated to make antennal contact with the excised heads of bees from a queen's court, providing further evidence that queen pheromone is transferred between workers' antennae.

Behavioral bioassays have confirmed that the oviposition-deterring secretion of the cabbage seed weevil, Ceutorhynchus assimilis Payk., can be isolated from glass tubes marked by the weevil and from extracts of its dissected seventh urotergite. Analysis of the secretion by gas chromatography—mass spectrometry showed that it contained iso- and n-alkanes, dimethylalkanes, alkenes, fatty acids, 15-nonacosanonc, 15-nonacosanol, and cholesterol. The oviposition-deterring properties of the secretion are associated with a more polar traction, isolated by liquid chromatography front an extract of the seventh urotergite.

The cabbage seed weevil (Ceutorhynchus assimilis Payk.) lays eggs singly into pods of oilseed rape (Brassica napus L.) through punctures bored with the mouthparts, preferring pods not recently used for oviposition. A simple new choice test has been used to test individual components of egg-laying behaviour for their effect on oviposition site selection. It is confirmed that an oviposition-deterring pheromone (ODP) is deposited during abdomen brushing of the pod which follows egg-laying. Neither pin punctures, weevil feeding punctures, oviposition punctures nor eggs had any deterrent effect. Pods walked on by female weevils were not avoided by those laying eggs. Observations suggest that the ODP is sensed by contact chemoreceptors on the antennae. The deterrent effect lasted only 1-2 h. The implications of these findings on the adaptive significance of the pheromone and its possible use in pest control are discussed.

In a series of three field experiments with factorial design, on sites that had not grown lupins previously, sowing date was the main factor affecting over-winter survival of autumn-sown white lupin. In 1993, the sowing dates (23 September and 20 October) were too late to prevent much plant death in autumn and early winter, with the onset of frosts. In 1994, the sowing dates (30 August and 22 September) were early enough to prevent severe frost damage, but infestations of bean seed fly (Delia platura) occurred, more in the later than in the earlier sown crops, causing wilting and plant death. Losses were decreased where furothiocarb seed treatment was applied. In 1995, losses were greater in early-sown (12 September) than in later sown (28 September) crops; plant death was gradual, occurring into the spring, and was apparently associated with over-development of young shoots before an unusually long, cold winter. A chlorpyrifos spray (13 or 29 September for early or late sown plots, respectively) slightly increased survival, possibly by controlling Thrips angusticeps. Fungicides applied to seed or as sprays in late autumn had little or no effect in these experiments. In another series of experiments to test fungicides, in 1992-93 and 1993-94, survival was poor following late sowing (in October), but was increased by application of prochloraz in December or January, or, in 1994, by seed treatment with thiram.

SUMMARYThe honeybee alarm pheromones 2·heptanone and isopentyl acetate were repellent to honeybee foragers when applied to plots of oil-seed rape and field beans and to sunflower heads. Their possible use to repel bees from crops before insecticide application is discussed.

SummarySynthetic (E)-citral, geraniol, nerolic acid and geranic acid components of the Nasonov gland pheromone induce worker honeybees (Apis mellifera) to release Nasonov pheromone at their hive entrance. Mixtures lacking any one of these 4 components stimulated pheromone release less effectively, but absence of nerol or (E, E)-farnesol increased effectiveness. The implication of these results for the development of a lure to attract honeybee swarms is discussed.

SummaryLures containing synthetic components of the honeybee Nasonov pheromone attract worker honeybees to traps, especially when they also contain the queen pheromone component (E)-9-oxo-2-decenoic acid.