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Both spraying with pesticides and using explosions to kill red-billed quelea (Quelea quelea) may affect non-target organisms and leave hazardous contaminants in the environment. Results of monitoring such effects in Botswana and Tanzania showed that although few non-target mortalities were noted, indirect effects in terms of depressed cholinesterases in birds and small mammals were marked and pesticides and contaminants from products used for the explosions persisted at controlled sites at unacceptable levels and for long periods (at least 188 days for sprays and at least 11 months for petroleum products and plastics).

Background: Spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), is an economically important pest of soft and stone fruit crops. The aim of this study was to identify repellents, formulated in dispensers, which could protect crops from D. suzukii. Fourteen potential repellents were screened against summer- and winter-morph D. suzukii through electroantennography and behavioural bioassays. Repellents effective in the laboratory were tested in polytunnels to determine their efficacy in reducing catches in fruit-baited traps. Further trials of three potential repellents were conducted to determine the distances over which repellent dispensers could reduce D. suzukii emergence in a strawberry crop., Results: All 14 chemicals screened were detected by the antennae of both D. suzukii morphs. Hexyl acetate and geosmin both elicited a significantly greater corrected EAG response in summer morphs than winter morphs. Summer-morph D. suzukii were repelled by butyl acetate, ethyl propionate, methyl N,N-dimethyl anthranilate, geosmin, methyl salicylate, DEET and benzaldehyde at one or more doses test in laboratory bioassays. Winter morphs were repelled by ethyl propionate, methyl anthranilate, methyl N,N-dimethyl anthranilate, DEET, benzaldehyde and butyl anthranilate at one or more of the doses tested in the laboratory. Ethyl propionate, methyl N,N-dimethylanthranilate and benzaldehyde repelled both morphs from fruit-baited traps in polytunnel trapping trials. Ethyl propionate and methyl N,N-dimethylanthranilate reduced emergence of D. suzukii in a strawberry crop over 3-5 m., Conclusions: Ethyl propionate and methyl N,N-dimethylanthranilate may protect strawberry crops against D. suzukii. Future work should test these repellents in combination with attractants in a 'push-pull' strategy. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

Background: European tarnished plant bug, Lygus rugulipennis (Heteroptera: Miridae), is a polyphagous pest damaging a range of arable and horticultural crops. Management is reliant upon chemical insecticides for control. These studies developed a synthetic semiochemical push-pull control strategy to reduce numbers of L. rugulipennis and subsequent fruit damage in UK strawberry crops. Using a series of small field experiments and testing in commercial strawberry crops we explored the efficacy of hexyl butyrate (HB) as the push element and female sex pheromone combined with phenylacetaldehyde as the pull element., Results: HB dispensers placed 1.0, 3.5, 5.0 and 7.0 m from all-green Unitraps baited with L. rugulipennis female sex pheromone significantly reduced male catches by 99%, 54%, 44% and 20% compared with untreated control, respectively. Subsequently, in commercial crops, HB dispensers at 2-m intervals along the crop row (the push) combined with a perimeter pull reduced numbers of adult and nymph L. rugulipennis by up to 80% in organic strawberry crops compared with the untreated control. Finally, the push-pull system halved fruit damage (8%) compared with untreated areas (16%) in conventional crops. In organic strawberry crops, 90% of untreated strawberries had some mirid damage compared with only 41-51% in push-pull-treated areas., Conclusion: To our knowledge, this is the first demonstration of a push-pull approach using synthetic semiochemicals giving a significant reduction in crop damage by mirids and paves the way for non-pesticide control of a range of mirid species on multiple crops. © 2021 Society of Chemical Industry., (© 2021 Society of Chemical Industry.)

Polyunsaturated hydrocarbons (Type II pheromone components) have been reported to be synergists for unsaturated acetates, alcohols or aldehydes (Type I components) in the sex pheromones of several species of Lepidoptera. However, there is some debate over whether the active components are the hydrocarbons themselves or more volatile degradation products. Extracts of pheromone glands of adult females of the cone moth, Dioryctria mendacella (Lepidoptera: Pyralidae), contain (Z,E)-9,11-tetradecadienyl acetate (ZE9,11-14:Ac) and at least ten times as much (Z,Z,Z,Z,Z)-3,6,9,12,15-pentacosapentaene (ZZZZZ3,6,9,12,15-25:H). The former elicits a strong electroantennogram response from males while no response could be recorded to the latter. In field trapping tests, both compounds were individually unattractive to male D. mendacella moths, but blends of the two compounds containing at least a 10:1 ratio of ZZZZZ3,6,9,12,15-25:H : ZE9,11-14:Ac were highly attractive. The relatively involatile hydrocarbon was shown to be released from the dispensers used and no significant degradation could be detected. Furthermore, blends of ZE9,11-14:Ac and analogs of ZZZZZ3,6,9,12,15-25:H with fewer carbons and/or double bonds that might be expected to produce similar degradation products to ZZZZZ3,6,9,12,15-25:H were unattractive. This indicated a specific response to the hydrocarbon itself, further substantiated by the observation that related hydrocarbons did not interfere with the activity of ZZZZZ3,6,9,12,15-25:H. Thus a three-step conversion of fish oil was used to produce a blend of unsaturated hydrocarbons containing ZZZZZ3,6,9,12,15-25:H as the major component, albeit only 30% of the total, and a blend of this material with ZE9,11-14:Ac was as attractive to male D. mendacella moths as blends with an equivalent amount of the purified material. This mixture of unsaturated hydrocarbons is much cheaper to produce than the pure pentaene, and may be useful in lures for other species using these compounds. Dioryctria mendacella is a major constraint to production of edible pine kernels throughout the Mediterranean region. Pheromone traps will provide a means to improve monitoring of seasonal flight patterns and changes in population abundance of this pest.

Mirid bugs (Heteroptera: Miridae) are important pests of many crops worldwide. In previous work by others and ourselves, several species of Lygus bugs were shown to produce blends of three compounds, hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-4-oxo-2-hexenal. These have been proposed as components of the female-produced sex pheromones, but attraction of males to synthetic lures has been difficult to demonstrate. We studied the volatiles released by females of four species: Lygus rugulipennis, Lygus pratensis, Lygocoris pabulinus, and Liocoris tripustulatus. Analyses of volatiles from individual, undisturbed insects showed that the three compounds were produced in species-specific blends, by females only, or in greater quantities by females than by males. The three compounds were loaded into pipette tips, which released the defined blends over at least 30 days. Traps baited with the blend for L. rugulipennis caught more males than traps baited with virgin females, with all three compounds required for maximum attractiveness. Traps baited with the specific blends for each of the four species caught males of three of the species, indicating considerable cross-attraction. There is evidence that other, non-chemical factors, such as time-of-day of production of pheromone, contribute to species-specificity of attraction. This is the first report of consistent attraction of Lygus bugs to synthetic lures in the field.

The sex pheromone of the chrysanthemum gall midge, Rhopalomyia longicauda (Diptera: Cecidomyiidae), the most important insect pest in commercial plantations of chrysanthemum, Dendranthema morifolium (Ramat.) Tzvel., in China, was identified, synthesized, and field-tested. Volatile chemicals from virgin females and males were collected on Porapak in China and sent to the United Kingdom for analysis. Coupled gas chromatographic-electroantennographic detection (GC-EAG) analysis of volatile collections from females revealed two compounds that elicited responses from antennae of males. These compounds were not present in collections from males. The major EAG-active compound was identified as 2-butyroxy-8-heptadecene by gas chromatographic (GC) retention indices, mass spectra, in both electron impact and chemical ionization modes, hydrogenation, epoxidation, and derivatization with dimethyldisulfide. The lesser EAG-active compound was identified as the corresponding alcohol. The ratio of butyrate to alcohol in the collections was 1:0.26. Racemic (Z)-8-heptadecen-2-ol and the corresponding butyrate ester were synthesized from (Z)-7-hexadecenyl acetate, and the synthetic compounds found to have identical GC retention indices and mass spectra to those of the natural, female-specific components. Analysis of the volatile collections on an enantioselective cyclodextrin GC column showed the natural pheromone contained (2S,8Z)-2-butyroxy-8-heptadecene. Field tests showed that rubber septa containing racemic (Z)-2-butyroxy-8-heptadecene were attractive to R. longicauda males. The (naturally occurring) S-enantiomer was equally as attractive as the racemate, while the R-enantiomer was not attractive to males, and did not inhibit the activity of the S-enantiomer. The attractiveness of the butyrate was significantly reduced by the presence of even small amounts of the corresponding alcohol.

Admission chest roentgenograms were reviewed of all patients diagnosed with pulmonary and extrapulmonary tuberculosis (TB) at the Medical College of Georgia--Eugene Talmadge Memorial Hospital (MCG-ETMH) during a five-year period from 1979 to 1983. Of 75 patients included, 51 had pulmonary TB, whereas 24 had extrapulmonary infection. Cavitary disease was common (28 of 51 patients with pulmonary TB). Forty-four of 51 patients with pulmonary TB had involvement of apical and/or posterior segments of the upper lobes with cavitation or infiltrates. Pleural effusion, parenchymal nodules, lymphadenopathy, and lower lung field disease were uncommon. Thirteen of 24 patients with extrapulmonary TB had abnormal admission chest roentgenograms, suggesting the possibility of Mycobacterium tuberculosis infection. Despite recent studies suggesting that TB presents with atypical roentgenographic features more commonly than reported in the past, the roentgenographic manifestations of TB in our series were typical of those previously described as pathognomonic for the disease.

52 women were examined, between the 25th and 40th wk of pregnancy, during the day-time, by the echographic multiscan/M-mode technique. Definitions of normal fetal breathing movements and singultus fetalis movements were determined. In normal pregnancies fetal breathing movements occurred during 12-19% of the total observation time before the 39th wk of pregnancy but only during 6-9% of the observation time in the 39th or 40th wk. In low birth weight pregnancies fetal breathing movements occurred during 8-13% of the total observation time, and the incidence was the same before and after the 39th wk. Singultus fetalis movements occurred in normal and low birth weight pregnancies.

Sixty patients with less than six weeks amenorrhoea were examined by ultrasonic "B" scanning for the detection of pregnancy. The results were compared with those obtained by histological examination of the aspirate after the patient had undergone menstrual regulation by vacuum aspiration of the uterine contents. The overall accuracy was 79 per cent with 15 per cent false positives. The accuracy after 39 days amenorrhoea was 95 per cent. The technique was compared with an immunological pregnancy test.