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Polyamines and their derivatives are ubiquitously present in free or conjugated forms in various foods from animal, plant, and microbial origins. The current knowledge of free polyamines in foods and their contents is readily available; furthermore, conjugated polyamines generate considerable recent research interest due to their potential health benefits. The structural diversity of conjugated polyamines results in challenging their qualitative and quantitative analysis in food. Herein, we review and summarize the knowledge published on polyamines and their derivatives in foods, including their identification, sources, quantities, and health benefits. Particularly, facing the inherent challenges of isomer identification in conjugated polyamines, this paper provides a comprehensive overview of conjugated polyamines’ structural characteristics, including the cleavage patterns and characteristic ion fragments of MS/MS for isomer identification. Free polyamines are present in all types of food, while conjugated polyamines are limited to plant-derived foods. Spermidine is renowned for antiaging properties, acclaimed as antiaging vitamins. Conjugated polyamines highlight their anti-inflammatory properties and have emerged as the mainstream drugs for antiprostatitis. This paper will likely help us gain better insight into polyamines and their derivatives to further develop functional foods and personalized nutraceuticals.

AbstractObjective:The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus.Design:The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance.Methods:MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method.Results:Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3.Conclusions:MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.

SummaryCulicoidesbiting midges (Diptera: Ceratopogonidae) serve as biological vectors for several pathogens, including the Bluetongue virus and the recently described Schmallenberg virus in northern Europe. These diseases have caused considerable direct and indirect economic losses to the sheep and cattle industries. This study undertaken between August and December 2007 on a sheep farm in the Namur province (Belgium) aims to evaluate Culicoidespopulations present inside a partially opened sheepfold and in a nearby sheep meadow, using light traps. The comparative analysis of insects trapped at 18 dates at regular intervals showed that Culicoideswere most abundant inside this livestock building (17,450 midges) than in surrounding meadow (1,121 midges); this meadow had however a greater species diversity. The two species C. obsoletusand C. scoticusconstituting the Obsoletus complex predominated for all trappings and females were much more numerous than males. Important capture of engorged females of the Obsoletus complex inside the sheepfold seems to reflect the possibility of an opportunistic endophagous behavior. Maintaining sheep inside livestock buildings in order to reduce the risk of Culicoidesbites – and thus of pathogens transmission – however requires to limit biting midge populations which are likely to enter or to develop inside these buildings. Implementation of effective sanitation and hygiene measures against midges present inside farms, as well as establishing of measures to protect livestock against intrusion and improvement of “midge-proofing” of animal housing are therefore highly recommended.

SummarySeveral species of Culicoides(Diptera: Ceratopogonidae) biting midges are biological vectors of bluetongue virus (BTV) and, as recently discovered, Schmallenberg virus (SBV) in northern Europe. Since their recent emergence in this part of the continent, these diseases that affect domestic and wild ruminants have caused considerable economic losses to the sheep and cattle industries. The substrates that are suitable for larval development of the main vector species are still relatively unknown. This study assessed all the substrates present in the immediate surroundings of a Belgian cattle farm and aimed to highlight the main breeding sites of these midge species. A total of 1639 immature Culicoidesand 1320 adult specimens belonging to 13 species were found in 15 out of the 43 substrates studied: maize silage residues for C. obsoletus/C. scoticus, old overwintered cattle dung in the meadow for C. chiopterusand C. dewulfi, ground of a flooded meadow, green filamentous algae and underlying substrate, silt from a pond, and ground of hollows caused by the crossing of machines on a dirt track for C. festivipennis, silt from a pond for C. nubeculosus, and ground of a flooded meadow for C. lupicaris. Identification of these micro-habitats and the associations among the species they contain could allow their localization and the development of new strategies of vector control, while preventing the creation of new Culicoideslarval micro-habitats. Finally, measures designed to reduce larval populations could improve efficacy of vaccination campaigns against BTV in Europe.

SummarySince 1999, European beekeepers have reported increased mortality in overwintering honey bee, Apis melliferaL. colonies. Viral infections are often cited as the potential cause for increased mortality. Many honey bee viruses commonly occur within bee populations and in many cases infected colonies appear asymptomatic. There is increasing evidence that the global spread of Varroa destructorhas resulted in a significant change in the prevalence, distribution and/or virulence of viruses causing mortality in honey bee colonies. We report here the first survey of the prevalence of five RNA bee viruses and their effect on overwintering survival of Belgian honey bee colonies. In the autumn of 2006, samples of adult bees were removed from 36 apiaries. Adult bee samples were analyzed by using RT-PCR for virus identification. Varroa mite prevalence in these samples was also quantified. A follow up visit of colonies in the spring permitted us to assess colony survivorship which permitted the effect, if any, of autumn varroa loads, virus presence and queen condition on colony survivorship to be ascertained. Although acute bee paralysis virus was the least prevalent of the detected honey bee viruses, it was strongly linked with increased colony mortality. Co-infection with more than two viruses also had an appreciable negative effect on colony survivorship.

RésuméLa Maladie de la Langue bleue est une maladie non contagieuse qui affecte les ruminants domestiques et sauvages. Depuis son extension au Nord de l’Europe en 2006, cette épizootie virale a engendré des pertes économiques considérables sur le cheptel ovin et bovin. Les vecteurs biologiques du virus de la FCO (BTV) sont des moucherons appartenant au genre Culicoides. De nombreuses inconnues subsistent encore sur leur biologie, physiologie, écologie et distribution. Cette étude montre que ces moucherons piqueurs sont bien plus abondants au niveau de la ferme que dans les prairies avoisinantes; ces dernières présentent toutefois une plus grande diversité spécifique. C’est ainsi que la possibilité de migration entre la prairie et la ferme est émise pour les espèces C. chiopteruset C. dewulfi. Tant pour la ferme que pour la prairie, les femelles sont beaucoup plus représentées que les mâles. L’observation de la physiologie de celles-ci est réalisée tout au long de l’étude.

AbstractHyptis spicigeraessential oils from seven localities in the North-Cameroon (Ngaoundere, Guirvidig, Kodeck, Lara, Toloum, Kaele, Tchecal-baila) were investigated by GC and GC/MS. Results showed differences within harvesting sites and between the different sites of collection but did not revealed clear tendencies in the evolution of the oil composition with regard to the sampling period. The main group of compounds in all the analyzed samples were: α-pinene (11.9%-42.1%), β-pinene + sabinene (6.0%-39.8%) and β-phellandrene + 1,8-cineole (8.8%-27.4%) except in one oil where β-caryophyllene (23.4%) was the principal component. The insecticidal activity of H. spicigeraand its principal terpenic components was evaluated against the cowpea weevil Callosobruchus maculatusF., the major cause of damages of cowpea (Vigna unguiculata(L.) Walp) in North Cameroon.

In this article, two theories are unified to investigate the effect of hydrodynamics on a specific bioprocess: the network-of-zones (NOZ) hydrodynamic structured modeling approach (developed by several researchers but applied to only a few bioprocesses) and the effectiveness factor η approach. Two process scales were investigated (20 and 500 L), and for each, hydrodynamics were quantified using an NOZ validated by homogeneity time measurements. Several impeller combinations inducing quite different hydrodynamics were tested at the 20-L scale. After this step, effectiveness factors were determined for each fermentation run. To achieve this, a perfectly mixed microbial kinetic model was evaluated by using simple Monod kinetics with a fed-batch mass balance. This methodology permitted determination of the effectiveness factor with more accuracy because of the relation with the perfect case deduced from the Monod kinetics. It appeared that for the small scale, η decreased until reaching a value of approx 0.7 (30% from the ideal case) for the three impeller systems investigated. However, stirring systems that include hydrofoils seemed to maintain higher effectiveness factors during the course of the fermentation. This effect can be attributed to oxygen transfer performance or to homogenization efficiency exhibited by the hydrofoils. To distinguish the oxygen transfer from the homogenization component of the effectiveness factor, these phenomena were analyzed separately. After determining the evolution of ηO2linked to oxygen transfer for each of the fermentation runs, the NOZ model was employed to quantify substrate gradient appearance. After this step, another effectiveness factor, ηmix, related to mixing was defined. Consequently, it is possible to distinguish the relative importance of the mixing effect and oxygen transfer on a given bioprocess. The results have highlighted an important scale effect on the bioprocess that can be analyzed using the NOZ model.

The volatiles released from several aphid and host plant species, alone or associated, were studied for their infochemical role in prey location. Using a four-arm olfactometer, the attraction of several combinations of three aphid (Myzus persicae, Acyrthosiphon pisum, and Brevicoryne brassicae) and three plant (Vicia faba, Brassica napus, and Sinapis alba) species toward Adalia bipunctatalarvae and adults was observed. Both predatory larvae and adults were attracted only by A. pisumand M. persicaewhen they were crushed, whatever the host plant. (E)-β-Farnesene, the aphid alarm pheromone, was the effective kairomone for the ladybird. Plant leaves alone (V. faba, B. napus, and S. alba) or in association with nonstressed whole aphids (the three species) did not have any attraction for the predator. The B. brassicaespecialist aphid is the only prey that was not attracted to A. bipunctatalarvae and adults, even if they were crushed. Release of B. brassicaemolecules similar to the host plant allelochemicals was demonstrated by GC–MS analysis. The lack of behavioral response of the ladybird at short distance toward the cruciferous specialist aphid was related only to the absence of (E)-β-farnesene in the aphid prey volatile pattern.

Flour beetles are cosmopolitan and common pests in grain stores and flour mills. Their ability to exploit a wide variety of stored products has contributed to their status as major pests of stored food. Although it was previously reported that the same aggregation pheromone, 4,8-dimethyldecanal (DMD), is shared by three flour beetles species (Tribolium castaneum, T. confusum, and T. freemani), the volatiles released by the other Triboliumspecies associated with stored products have not yet been examined. In the present study, the volatiles produced by males and females of eight Triboliumspecies were examined by solid phase microextraction (SPME). SPME samples were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). Experiments were conducted to identify volatiles emitted by the adults of different Triboliumspecies and to determine whether DMD is a common aggregation pheromone. We observed that DMD is not a common pheromone of the eight species tested, but is common to T. castaneum, T. confusum, T. freemani, and T. madens. Two other volatiles were detected, 1-pentadecene, which is shown here to be a common semiochemical of flour beetles, and 1,6-pentadecadiene, which was detected in five species (T. audax, T. brevicornis, T. destructor, T. freemani, and T. madens).

The Episyrphus balteatushoverfly is commonly found in very diversified biotopes including Brassicaceae crop fields. Glutathione S-transferases (GST) are detoxification enzymes that are involved in the metabolization of plant allelochemicals such as glucosinolates and related volatile products (mainly isothiocyanates) from Brassica plants. Developmental expression of E. balteatusglutathione S-transferases was studied. With regard to the high level of glutathione S-transferase activity in syrphid adults, the latter stage was also used to assess the glutathione S-transferase distribution in several parts of the insect. Higher glutathione S-transferase activities were found in the thorax (47.5 and 38.5%) followed by the abdomen (32.4 and 32.9%) and the head (20.4 and 28.5%) with 1-chloro-2,4-dinitrobenzene, and 2,4-dinitro-l-iodebenzene, respectively. Analysis of Brevicoryne brassicae, the cabbage aphid, by GC-MS revealed the presence of isothiocyanates. The latter are the main degradation products of the glucosinolate from the host plant at neutral pH. Feeding the predators with this aphid species and with the generalist Myzus persicaereared on Brassica napusinduced glutathione S-transferase activity. Impact of volatiles from the host plant on the glutathione S-transferase activity was also determined by exposure of syrphid larvae to isothiocyanates (allyl- and benzyl-isothiocyanates). Enzyme inductions were observed only from a 1 ppm concentration. Enzymatic activity evolution was discussed as an adaptation to cope with allelochemicals from plants. Finally, the glutathione S-transferase activities of several hoverfly species were compared in relation to their feeding behavior (coprophagous, saprophagous, and aphidophagous) at the larval stages. The results seem to indicate quantitative and qualitative differences of glutathione S-transferases according to the feeding behavior of the larvae.

Disruptive selection between large, nutritive gametes and numerous, competing gametes may have driven the evolution and maintenance of anisogamy. Sperm competition can explain why there are so many tiny sperm because numerical competition between rival gametes drives males to maximize sperm number and this may be achieved by minimizing sperm size. Since males operate within a finite reproductive budget and ejaculate production is limited, we might predict that, when variation in sperm size exists, males must trade increases in sperm size against a decrease in sperm number. We use Tribolium castaneum as our model to investigate the existence of a sperm size–number trade-off. We sampled 14 different populations that have been isolated for different periods (up to 39 years) and find across this sample of 70 males that there is significant variation in both sperm length and ejaculate sperm number between males. Despite this significant variance, we find no evidence for any relationship between sperm size and number across males. There is some evidence for a trade-off when we analyse across 14 population means, but this relationship is not robust and disappears when a single outlier is omitted. We conclude that sperm size and ejaculate sperm number vary independently, but that differential allocation to gonadal tissue and/or ejaculation frequency would permit this independent variation.

Fourteen strains of Tribolium castaneum(Herbst) (Coleoptera: Tenebrionidae) had mortalities ranging from 5 to 100% when exposed to diatomaceous earth at 600 ppm for seven days. The most tolerant strain had a lethal dose for 50% of the population (LD50) of 413 ppm and the most susceptible strain had a LD50of 238 ppm. Adults of the tolerant strain were lighter (2.0 mg) than the susceptible strain (2.6 mg). Tolerant adults lost water at lower rate (6 μg h−1than susceptible adults (12 μg h−1), when held in wheat treated with 600 ppm diatomaceous earth for 24 h, than held at 5% r.h. with no food. Tolerant adults that were not exposed to diatomaceous earth lost water at a lower rate (3 μg h−1) than susceptible adults (5 μg h−1). Both strains, exposed and not exposed to diatomaceous earth died when their water content was between 33 and 37% of their total weight. Insects taken directly from the cultures had 52% (tolerant) and 53% (susceptible) of their total weight as water. Tolerant adults moved slower through grain and across filter paper than susceptible adults. Tolerant adults avoided wheat treated with diatomaceous earth at concentrations as low as 75 ppm, whereas the adults from the susceptible strain did not avoid diatomaceous earth, even at 600 ppm. The consequences of a strain tolerant to diatomaceous earth is discussed with respect to the use of diatomaceous earth to control stored‐product insect infestations.

Sperm precedence is a useful descriptor of the outcome and possible processes of sperm competition between (usually) two males. Although sperm precedence values are known for a variety of taxa, a characteristic feature has been the profound, and largely unexplained, variance in precedence. In this study we partition some of the precedence variance in Tribolium castaneum(Herbst) (Coleoptera, Tenebrionidae) by examining how: (1) sperm precedence changes with time over a one‐month oviposition period, (2) precedence is influenced by the relative timing of the two competitive mating periods, and (3) sperm precedence is affected when three, rather than the normal two, males are placed in sperm competition. In general, last male sperm precedence is high (≈ 90%) for the first few days after mating, but this changes significantly with time as previous males' sperm become used in fertilization. We find that the duration between two competitive mating bouts has a significant effect on precedence (even when relatively brief): longer intervals between mating bouts result in more complete and persistent last‐male sperm precedence. The dynamics of last‐male sperm precedence when there are three males in the competition are not significantly different to precedence results when only two males are in competition. Our results are consistent with the hypothesis that, soon after inseminations, male ejaculates ‘stratify’ in the narrow and elongate storage tubules of the spermatheca. With time we see increased variance in individual male precedence as sperm from previous matings achieve more fertilizations. This change over time may result from depletion (either via fertilizations or passive/active sperm loss) of the last males' sperm and/or increased mixing of different males' sperm within the spermatheca.

Three Brassicaceae species, Brassica napus (low glucosinolate content), Brassica nigra (including sinigrin), and Sinapis alba (including sinalbin) were used as host plants for two aphid species: the generalist Myzus persicae and the specialist Brevicoryne brassicae. Each combination of aphid species and prey host plant was used to feed the polyphagous ladybird beetle, Adalia bipunctata. Experiments with Brassicaceae species including different amounts and kinds of glucosinolates (GLS) showed increased ladybird larval mortality at higher GLS concentrations. When reared on plants with higher GLS concentrations, the specialist aphid, B. brassicae, was found to be more toxic than M. persicae. Identification of GLS and related degradation products, mainly isothiocyanates (ITC), was investigated in the first two trophic levels, plant and aphid species, by high-performance liquid chromatography and gas chromatography–mass spectrometry, respectively. While only GLS were detected in M. persicae on each Brassicaceae species, high amounts of ITC were identified in B. brassicae samples (allyl-ITC and benzyl-ITC from B. nigra and S. alba, respectively) from all host plants. Biological effects of allelochemicals from plants on predators through aphid prey are discussed in relation to aphid species to emphasize the role of the crop plant in integrated pest management in terms of biological control efficacy.

There is increasing evidence that normal male reproductive function can be disrupted by exposure to pollutants in the environment that can exogenously mimic, antagonize or block sex–hormone function. One possible consequence of exposure to these xenobiotics is disruption to spermatogenesis, but results thus far provide only indirect and inconsistent evidence. In this study we exposed adult male guppies (Poeciliidae: Teleostei) to environmentally relevant levels of the common xenobiotics tributyltin (11.2–22.3 ng l–1) and bisphenol A (274–549 μg l–1) in experimental aquaria. After 21 days of exposure, we found significant declines (by 40–75%) in total sperm counts for male fishes exposed to tributyltin and bisphenol A compared with controls. This short–term decline in sperm count is unlikely to be the result of endocrine–mediated alteration of the germ line, and we found no change in testis size or sperm lengths between treatments. However, Sertoli cells, which facilitate the transport of maturing sperm into the testicular deferent duct (where they are stored prior to ejaculation), are directly sensitive to xenobiotic action and it is therefore possible that spermatogenesis was inhibited through in vivointerference with normal Sertoli–cell function.

The differential inhibition of acetylcholinesterase (AChE) by organophosphate (OP) and carbamate (C) is followed by the distinct duration of exposure effect on common carp AChE. Hence, in the present study in vivoexposure period effect and in vitroconcentration–response of chlorfenvinphos, chlorpyrifos diazinon, and carbofuran were investigated on Cyprinus carpioL. AChE. Individuals of 1-year-old carp were exposed for 96 h to different concentrations of insecticides, after which AChE activity was measured in the brain. The highest concentrations of carbofuran (2.44 mg·L−1), chlorfenvinphos (2.9 m·L−1), and diazinon (2.5 mg·L−1) killed all the test animals after only 4 h, although there was no statistically significant difference from the control group's brain AChE activity. The lowest concentration significantly inhibited brain AChE after 96 h. Chlorfenvinphos was the most potent inhibitor in vivoand chlorpyrifos the least active inhibitor after 96 h of exposure time. In vitroexperimentation with the same pesticide indicated that several concentrations inhibited 50% of the AChE activity (I50), ranging from 4.1×10−7to 8.12×10−4M in both single inhibitory action and joint inhibitory effect. The results suggest that in biomonitoring programs carp brain AChE can be a good diagnostic tool for chronic OP nd C pollution.

Margosan-O®, a commercial neem-based insecticide, incorporated into an artificial diet prolonged the development of larvae of Spodoptera littoralisBoisduval. It also affected the rate of adult emergence at the end of pupation. Larvae treated during one stadium continued to show the effects of their previous exposure. The susceptibility to Margosan-O was more pronounced when larvae ate the diets containing Margosan-O for the first time during the fifth or sixth instar. The results indicate that Margosan-O has an activity similar to that of other neem-seed extracts. In the course of this work morphological anomalies were also recorded. The most striking was the appearance of black stripes on the abdominal tergites of the fifth and sixth instar larvae fed on diets containing 0.01, 0.05 or 0.1% of Margosan-O. Un insecticide commercial à base d’azadirachtine (Margosan-O®), incorporé à la nourriture artificielle, a prolongé la durée de développement des larves de Spodoptera littoralisBoisduval. Il a également affecté le nombre d’émergence d’adulte à la fin du stade nymphale. Les larves traitées pendant un stade donnée continuaient à manifester les effets de leur exposition au substrat. La sensibilité du Margosan-O était plus importante lorsque les larves se nourrissaient d’un substrat contenant Margosan-O au cours du cinquième et sixième stade. Les résultats montrent que le Margosan-O a la même activité que d’autres extraits à base de neem. Cet insecticide provoque également chez Spodoptera littoralisdes anomalies morphologiques au cours des stades de développement; des bandes noires apparaissent sur les tergites abdominales lorsque les larves du cinquième et du sixième stade se nourrissent d’un substrat contenant 0.01, 0.05, ou 0.1% de Margosan-O.

ABSTRACTA steam-distillated essential oil (1% yield) obtained from the dried leaves of Piper acutifolium(Piperaceae) was analyzed by capillary GC and GC/MS. The major constituents identified were: (E)-β-ocimene (8.1%), α-copaene (6.1%), allo-aromadendrene (6.0%), α-cadinene (6.7%), δ-cadinene (6.8%), myristicin (4.2%) and dillapiole (5.9%). The oil was evaluated for biological activity against Callosobruchus maculatus(a stored grain insect pest). There was no effect on mortality; however, a significant decrease in oviposition was observed.

Since its first report in 2000, the invasive mosquito Aedes albopictuswas not found any more during the different entomological inspections performed at its place of introduction in Belgium between 2001 and 2012. In July 2013, one adult male was captured at the same site (a platform of imported used tires located in Vrasene, Oost-Vlaanderen Province), during a monitoring using CO2-baited trap. This finding suggests the reintroduction of the species in Belgium via the used tire trade.

AbstractA water-distilled oil obtained from fresh leaves of A gastache scrophulariaefolia(Lamiaceae) in 0.8% yield was analyzed by capillary GC and GC/MS. The main constituents identified were: limonene (11.4%), menthone (7.6%), isomenthone (49.7%) and (1S) (-) pulegone (19.8%). The oil was shown to exhibit a fumigant effect against the stored grain insect pest Callosobruchus maculatus.

The complex microbial community living in the hindgut of lower termites includes prokaryotes, flagellates, yeasts, and filamentous fungi. Many microorganisms are found in the termite gut, but only a few are thought to be involved in symbiotic association to participate in cellulose digestion. Proteomics provides analyses from both taxonomical and functional perspectives. We aimed to identify symbiont diversity in the gut of Reticulitermes santonensis (Feytaud), via complementary electrospray ionization associated to ion trap tandem mass spectrometry (LC-MS/MS) and two-dimensional gel electrophoresis associated to matrix-assisted laser desorption-ionization-time-of-flight mass spectrometry analysis. One specific challenge to the study of lower termites is the relatively few data available on abundant symbiotic flagellates. Analysis based on LC-MS/MS revealed few protein families showing assignments to eukaryotes and the taxonomic origin of highly represented actins could not be established. Tubulins proved to be the most suitable protein family with which to identify flagellate populations from hindgut samples using LC-MS/MS, compared with other protein families, although this method targeted few prokaryotes in our assay. Similarly, two-dimensional gel electrophoresis associated to matrix-assisted laser desorption-ionization-time-of-flight mass spectrometry did not succeed in identifying flagellate populations, but did permit the identification of most of the prokaryotic components of the symbiotic system. Finally, fungi and yeasts were identified by both methods. Owing to the lack of sequenced genes in flagellates, targeting tubulins for LC-MS/MS could allow fingerprints of flagellate populations to be established. Experimental and technical improvements might increase the efficiency of identification of prokaryotic populations in the near future, based on metaproteomic development.

Colony collapse disorder (CCD), a syndrome whose defining trait is the rapid loss of adult worker honey bees, Apis mellifera L., is thought to be responsible for a minority of the large overwintering losses experienced by U.S. beekeepers since the winter 2006-2007. Using the same data set developed to perform a monofactorial analysis (PloS ONE 4: e6481, 2009), we conducted a classification and regression tree (CART) analysis in an attempt to better understand the relative importance and interrelations among different risk variables in explaining CCD. Fifty-five exploratory variables were used to construct two CART models: one model with and one model without a cost of misclassifying a CCD-diagnosed colony as a non-CCD colony. The resulting model tree that permitted for misclassification had a sensitivity and specificity of 85 and 74%, respectively. Although factors measuring colony stress (e.g., adult bee physiological measures, such as fluctuating asymmetry or mass of head) were important discriminating values, six of the 19 variables having the greatest discriminatory value were pesticide levels in different hive matrices. Notably, coumaphos levels in brood (a miticide commonly used by beekeepers) had the highest discriminatory value and were highest in control (healthy) colonies. Our CART analysis provides evidence that CCD is probably the result of several factors acting in concert, making afflicted colonies more susceptible to disease. This analysis highlights several areas that warrant further attention, including the effect of sublethal pesticide exposure on pathogen prevalence and the role of variability in bee tolerance to pesticides on colony survivorship.

Secondary plant substances, also called allelochemicals, play a major role in pest infestations. Glucosinolates (GLS) and their degradation products are powerful phagostimulants for herbivores feeding on Brassicaceae and deter the noncrucifer feeders but are tolerated by some generalist phytophagous insects such as the peach-potato aphid, Myzus persicae Sultzer. Do the allelochemical substances only effect the herbivores or do they also influence the predators of the pest? Broad bean, Vicia faba L. (GLS free), oilseed rape, Brassica napus L. (low GLS level), and white mustard, Sinapis alba L. (high GLS level), were used in this work as host plant for the prey. Although the two latter Brassicaceae species had positive effects on aphid reproductive rates, host plants displayed mixed influences on the performance of the predaceous twospotted lady beetle, Adalia bipunctata L. Both rape and mustard shortened development duration and increased adult weight of the twospotted lady beetle. No significant difference of lady beetle mortality was observed, depending on the prey host plant. Whereas, rape-fed M. persicae enhanced larger egg production and larvae emergence, mustard-fed M. persicae induced lower fecundity and egg viability of the beetles. Fitness of M. persicae on high GLS plant-fed A. bipunctata was lower than the other plants. Biological parameters of aphid predators are closely linked to chemical composition of Brassicaceae species. This work on allelochemical impact gave opportunities to better understand interactions of the plant-aphid-lady beetle tritrophic model and demonstrated that successful biological control of pests must integrate the environmental aspects of each trophic level.

Malathion resistance in the red flour beetle, Tribolium castaneum (Herbst), is a worldwide problem and is very stable once it becomes widespread in natural populations. In the absence of insecticide the proportion of resistant phenotypes may rapidly decline but the development of resistance does not always involve reduced fitness. Malathion-specific resistance in T. castaneum seems not to involve any loss of fitness in laboratory or field conditions. Susceptible beetles were in competition with resistant beetles at different initial frequencies and modifications of susceptible gene frequency were estimated in these laboratory populations over 10 generations. A significant decrease in susceptible gene frequency was observed in Tribolium populations over time. The selection coefficient of the susceptible allele was estimated and the fitness of susceptible alleles in all tests was observed to range from 0.89 to 0.93 compared with the fitness of resistant genotypes, which was assumed to be 1. Data provided evidence that the resistant strains exhibited fitness advantages in the absence of malathion. We also compared the biotic potential (fecundity and developmental time) of the susceptible strain, the homozygous malathion-specific resistant strain, and their hybrids. Malathion-specific resistant strains showed an 8–23% increase in biotic potential relative to the susceptible strain. These findings are consistent with those of malathion-specific resistance in T. castaneum; the fitness of the insects seems independent of the genetic background and the fitness of the resistant insects is not affected by this resistance mechanism.