bluuebunny/crossref_metadata_2025 huggingface dataset:
The distribution of the vetch aphid on bean stems in relation to stylet length and phloem depth
Authors: Elliott Daphne I. , Hodgson Chris J.
Published: March 2011

Phloem depth in Vicia faba (L.) (Leguminosae) and stylet length in apterous Megoura viciae Buckt. (Homoptera, Aphididae) were both found to increase with age, so that phloem in the late mature stem and corner ridges of the whole stem were not accessible to young nymphs. The aphids of all ages used 75% of their total stylet length to reach the phloem by routes which were shown, by scale drawings and graphs, to be circuitous, curved, extracellular and sometimes intramural. After prolonged infestation, a dense network of stylet tracks was found in the stem cortex. Phloem accessibility determined the distribution of aphids, which preferred the mature stem and the narrow channels either side of the corner ridges. The results are discussed as the aphids' response to a dynamic resource system in the maturing stem.
Behavioral and physiological responses of Diaeretiella rapae to semiochemicals
Authors: Vaughn T. T. , Antolin M. F. , Bjostad L. B.
Published: March 2011

Diaeretiella rapae (M'Intosh) (Hymenoptera: Braconidae) parasitizes many aphid species, including cabbage aphids on cruciferous crops and Russian wheat aphids on cereal crops. We investigated the olfactory perception of D. rapae to semiochemicals that may be encountered in these two environments while searching for hosts or for mates. We conducted electroantennogram and flight‐tunnel experiments on male and female D. rapae and found marked differences between sexes. Cruciferous volatiles elicited physiological and behavioral responses by females but not by males. Males and females responded similarly to (Z)‐3‐hexen‐1‐ol, a component of green‐leaf volatiles, in both electroantennogram and flight‐tunnel assays. Female wasps responded similarly regardless of prior oviposition experience or population origin. Likewise, mating history and aphid presence did not increase responsiveness toward these semiochemicals.
The effect of wilting on the selection of leaves by the leaf‐cutting ant Atta laevigata
Authors: Vasconcelos H. L. , Cherrett J. M.
Published: March 2011

Using field assays of leaf preference, we tested the hypothesis that wilting affects the selection of leaves by the leaf‐cutting ant Atta laevigata (Fr. Smith). Detached leaves were left to air‐dry until noticeably wilted. The area removed by the ants from wilted leaves was significantly greater than the area removed from fresh leaves, this effect being observed in several plant species, in leaves of different age, and in assays with different ant colonies. Leaves collected from water‐stressed plants were also preferred to leaves from non‐stressed plants.

A. laevigata was found to employ a two‐stage, size‐related, strategy when cutting plants. Larger workers climbed the plant stem and dropped whole leaves to the ground by severing their petioles; smaller workers cut the lamina of the dropped leaves. The ants frequently left dropped leaves on the ground, until the next foraging day or even later, when they were harvested in a wilted condition in preference to newly‐dropped leaves.

It is possible that during wilting some repellent substances evaporate or become less effective, thus enhancing leaf palatability. Alternatively or in addition, changes in nutrient and water content may have rendered wilted leaves more palatable to leaf‐cutting ants.
Interspecific interference betweenApoanagyrus lopeziandA. diversicornis, parasitoids of the cassava mealybugPhenacoccus manihoti
Authors: Pijls Janine W. A. M. , Poleij Leo M. , van Alphen Jacques J. M. , Meelis Evert
Published: March 2011

The parasitoidsApoanagyrus lopeziDe Santis andA. diversicornis(Howard) (Hymenoptera: Encyrtidae) have been introduced into Africa for the biological control of the cassava mealybugPhenacoccus manihotiMatile‐Ferrero (Homoptera: Pseudococcidae). We have studied competition between these species to investigate if they can coexist. Here we report on the influence of the simultaneous presence of non‐conspecific adult females on searching efficiency on patches. Wasps of either species foraged on discs of cassava leaf with mealybugs, while at the same time different numbers of non‐conspecifics were also depleting the patch. Patch area per parasitoid and number of hosts available to each parasitoid were equal in all treatments.

In both species, the presence of other foragers clearly affected several aspects of the parasitoids' behaviour. Patch residence time increased with the number of non‐conspecifics inA. diversicornis.In both parasitoid species, the proportion of hosts left unparasitized after the patch visit decreased with increasing numbers of females on the patch. The proportions of super‐ and multiparasitism did not change with the number of females. Both species produced more offspring during a patch visit in the presence of more non‐conspecifics. These behavioural changes did not, however, lead to a change in the offspring production rate on patches.A. diversicornisproduced offspring at a rate three times that ofA. lopeziwhen oneA. lopeziand oneA. diversicornisforaged simultaneously. This is the first report of an aspect of interspecific competition whereA. diversicornishas an advantage overA. lopezi.Interference between adult females thus promotes coexistence of the two species onP. manihoti.
Effects of glucobrassicin, epiprogoitrin and related breakdown products on locusts feeding: Schouwia purpurea and desert locust relationships
Authors: El Sayed G. , Louveaux A. , Mavratzotis M. , Rollin P. , Quinsac A.
Published: March 2011

The glucosinolates of a Saharan crucifer Schouwia purpurea (Forskål) (Brassicaceae) were determined by liquid chromatography. Two of these glucosinolates and sinigrin were tested for their deterrent effect on Schistocerca gregaria (Forskål) (Orthoptera: Acrididae). Glucobrassicin, three indolyls and epigoitrin were synthesized for this purpose. Epiprogoitrin was extracted from Crambe seeds. Choice tests on artificial substrate compared feeding responses to glucosinolates and to related breakdown products released when the plant is eaten. Breakdown products were more efficient in deterring the generalist locust than were glucosinolates. Two patterns of dose responses were recorded: glucosidic compounds deterred or stimulated feeding, depending on the concentration tested; aglycones did not stimulate feeding at any concentration. Allyl isothiocyanate, a volatile compound, was a 100‐fold higher deterrent than its substrate (sinigrin).
The apple sawfly, Hoplocampa testudinea: a temperature driven model for spring emergence of adults
Authors: Graf B. , Höhn H. , Höpli H. U.
Published: March 2011

The effect of temperature on post‐diapause development of the apple sawfly Hoplocampa testudinea Klug was studied under controlled conditions. Survival was found to decrease at temperatures higher than 15 °C, the lethal temperature being close to 25 °C. The lower thermal threshold was 4.5 °C; the values for males and females did not differ significantly. However, different values were established for unprotected individuals, in vermiculite and in potting compost respectively. Based on the overall mean and variance of the developmental time and the overall thermal threshold a simple soil temperature driven phenology model was constructed using a time‐ varying distributed delay. The validation with independent field and semi‐field data revealed the model to be a reliable tool to predict apple sawfly phenology and hence to determine the optimal time for the installation of white sticky traps or for control measures such as insecticide treatments.
Repellency of essential oils and their components to the human body louse, Pediculus humanus humanus
Authors: Mumcuoglu Kosta Y. , Galun Rachel , Bach Uri , Miller Jacqueline , Magdassi Shlomo
Published: March 2011

Five essential oils and nine of their components were compared to diethyl toluamide (DEET) for their repellent activity against the human body louse, Pediculus humanus humanus. The absolute or intrinsic repellency of the compounds was tested by applying the repellent to corduroy patches and comparing them with untreated patches. It was found that the most effective repellents were DEET and citronella, whose activity lasted at least 29 days. The activity of rosemary lasted at least 18 days and that of eucalyptus more than 8 days. The repellent activity of the oil components such as citronellal and geraniol lasted more than 15 and 8 days, respectively. DEET remained effective at a dilution of 1:32, geraniol at 1:8, citronella at 1:4 and rosemary and citronellal at 1:1. The comparative or standard repellency of the candidate repellents was examined with the aid of a new screening technique using hairs treated with ammonium bicarbonate which is attractive to lice. Using this technique it could be shown that the repellent activity of citronella and geraniol lasted 2 days and that of rosemary and citronellal for only one day. DEET was active for less than one day. Serial dilutions of these substances also revealed that citronella was the most potent repellent for lice, followed by citronellal, rosemary, geraniol and DEET. The differences however, were not significant.
Low aromatic amino acid concentrations in leaf proteins determine resistance to Frankliniella occidentalis in four vegetable crops
Authors: Mollema C. , Cole R. A.
Published: March 2011

Analysis of total aromatic amino acid (free and bound) in some cucumber accessions selected previously for resistance to western flower thrips, Frankliniella occidentalis (Pergande) [Thysanoptera: Thripidae], indicated that low concentrations of these essential nutrients, relative to total leaf protein, were correlated with a reduction in damage by the insect. Further analysis of samples of four important horticultural crops (lettuce, tomato, pepper and cucumber) with unknown levels of resistance to thrips showed a significant genotypic variation in the concentrations of total aromatic amino acids relative to the total leaf protein. Accessions from each crop with low or high concentrations of aromatic amino acids in proteins were exposed to thrips larvae. Regression analysis showed a highly significant positive correlation between aromatic amino acid concentration in leaf protein and thrips damage, regardless of crop species. It is concluded that higher concentrations of aromatic amino acids in plant proteins are important for successful thrips development. These results provide plant breeders with a promising tool for indirect selection without using undesirable insect bioassays.
Activity of natural toxins against the silverleaf whitefly, Bemisia argentifolii, using a novel feeding bioassay system
Authors: Davidson Elizabeth W. , Patron Rufino B. R. , Lacey Lawrence A. , Frutos Roger , Vey Alain , Hendrix Donald L.
Published: March 2011

An assay system was developed for the adult silverleaf whitefly, Bemisia argentifolii Bellows & Perring (Homoptera: Aleyrodidae). This practical device was constructed from standard disposable laboratory materials. Whiteflies were harvested directly from the leaf and into a collection vial by vacuum aspiration, minimizing physical damage to the insect. Insects were fed through a cellulose mixed‐ester membrane on a diet of 20–27% sucrose alone or sucrose in an extract of zucchini (Curcurbita moschata Duchense). Mortality and honeydew production were scored. At 22–25 °C and 50–55% relative humidity, control mortality generally remained at or below 15% during a 48 h assay period. The bioassay system was first tested using the insecticide, Imidacloprid, then used to screen a number of natural products with potential insecticidal activity against the whitefly. Destruxins extracted from the entomopathogenic fungus, Metarhizium anisopliae, and the natural insecticide/nematicide, Ivermectin, as well as bee venom and two of its components, melittin and phospholipase A2, were found to be toxic to B. argentifolii. Five lectins, Bacillus thuringiensis toxins, gossypol, an extract of Paeciliomyces fumosoroseus, wasp and scorpion venom, and a trypsin inhibitor were not found to be insecticidal to adult B. argentifolii.
The effect of neem allelochemicals on nutritional physiology of larval Spodoptera litura
Authors: Koul Opender , Shankar J. S. , Kapil R. S.
Published: March 2011

Neem allelochemicals azadirachtin, salannin, nimbinene and nimbin were administered to different larval instars of the tobacco armyworm, Spodoptera litura orally in artificial diet, topically or via injection. Nutritional analyses revealed strong antifeedant and growth regulatory effects of azadirachtin which were independent of each other. While salannin and nimbinene induced concentration dependent feeding deterrence only; nimbin was inactive to the 1000 ppm level against this insect species. One of the causes of the reduced growth rate of azadirachtin treated insects was due to an increase in the costs associated with growth. This was relative to a drastic reduction in the activity of gut trypsin. Salannin and nimbinene, however, did not interfere with the trypsin activity of the gut. These results and those from nutritional studies suggest that salannin and nimbinene have no toxicity mediated effects on S. litura larvae and antifeedant activity is a result of the effects on deterrent and other chemoreceptors. The fact that azadirachtin directly or indirectly inhibits the secretion of trypsin by the enzyme‐secreting cells of the gut is discussed.
Influence of galls ofPhanacis taraxacion carbon partitioning within common dandelion,Taraxacum officinale
Authors: Bagatto Giuseppe , Paquette Louise C. , Shorthouse Joseph D.
Published: March 2011

We examined how leaf galls, induced by the cynipid waspPhanacis taraxaci, influence the partitioning of photoassimilates within the host, the common dandelion,Taraxacum officinale.Galled and ungalled plants were exposed to14CO2and the labelled photoassimilates accumulating within galls and other parts of the host were measured. During the growth phase of the gall they were physiological sinks for photoassimilates, accumulating 9% to 70% of total carbon produced by the host, depending upon the number of galls per plant. High levels of14C assimilation in the leaves of galled plants compared to controls, suggest that galls actively redirect carbon resources from unattacked leaves of their host plant. This represents a significant drain on the carbon resources of the host, which increases with the number and size of galls per plant. Active assimilation of14C by the gall is greatest in the growth phase and is several orders of magnitude lower in the maturation phase. This finding is consistent with physiological and anatomical changes that occur during the two phases of gall development and represents a key developmental strategy by cynipids to ensure adequate food resources before larval growth begins.
Electrical Penetration Graphs from Peregrinus maidis on a susceptible maize hybrid
Authors: Buduca C. , Reynaud B. , Luk D. Lan Sun , Molinaro F.
Published: March 2011

The feeding behavior of Peregrinus maidis (Ashmead) (Homoptera: Delphacidae), vector of maize mosaic virus (MMV) and maize stripe virus (MStpV) in maize (Zea mays L.), has been studied by Electrical Penetration Graph (EPG). The different recordings collected have allowed the temporal distinction of three EPG signal classes. These class 1, class 2 and class 3 signals are correlated through histological sections to the feeding activities of probing, xylem ingestion and phloem ingestion, respectively. Although these signals are described by various statistical parameters, only the median allows significant differentiation between class 2 and class 3 signals, the others varying from one insect to the next. On the other hand, spectral analysis is used to describe the signal classes by associating a characteristic frequency spectrum to each. This study treats the importance of such analysis in characterizing and comparing the signals of various piercing and sucking insects.
Inter‐ and intra‐instar food consumption in the German cockroach, Blattella germanica
Authors: Valles Steven M. , Strong Charles A. , Koehler Philip G.
Published: March 2011

Food consumption was measured in an insecticide‐susceptible (Orlando) and ‐resistant (Village Green) strain of German cockroach, Blattella germanica (Dictyoptera: Blattellidae), throughout each stadium. All instars exhibited a similar pattern of consumption over the course of the instar; consumption was low to moderate at the beginning of each instar, climbed steadily to a maximum near the middle, declined progressively from the mid‐instar maximum, and ceased or was minimal several days before the next molt. Consumption ceased or was minimal during the final two to four days of each instar. Cumulative consumption for the six instars was significantly greater in the Village Green strain as compared with the Orlando strain. Village Green nymphs consumed 79.6 ± 0.7 mg of rat chow while Orlando nymphs consumed 63.7 ± 3.4 mg. Total consumption by instar increased significantly with each successive instar in the Village Green strain. In addition, Village Green sixth instar females consumed significantly more food than sixth instar males. A similar trend was observed for the Orlando strain; consumption tended to increase in each successive instar. Relative consumption rate (food consumed/cockroach/instar divided by the mean weight of the instar) was highest in the first two instars and decreased in subsequent instars.
Behavioural and sensory responses to drimane antifeedants in Pieris brassicae larvae
Authors: Messchendorp L. , VAN Loon J. J. A. , Gols G. J. Z.
Published: March 2011

Fifteen drimane compounds were tested for their feeding inhibiting activity in larvae of Pieris brassicae L. (Lepidoptera: Pieridae) when applied to leaf material of the host plant Brassica oleracea L. The antifeedant efficacy of the drimanes was related to their molecular structure in order to identify important functional groups. Of the drimanes tested, those with a lactone group on the B‐ring were the most effective feeding inhibitors. Additionally, the sensory responses to 13 of the drimanes were measured. Neural activity was evoked in the deterrent cell in the medial sensillum styloconicum. Also, inhibition of sensory responses to feeding stimulants was found. Results of behavioural and electrophysiological tests were correlated in an attempt to elucidate the sensory code underlying feeding inhibition by drimanes in Pieris brassicae. It was concluded that the response of the deterrent cell in the medial sensillum styloconicum contributes significantly to inhibition of feeding behaviour in larvae of Pieris brassicae.
Morphological variation in Planococcoides njalensis occurring on cocoa in Ghana
Authors: Padi B. , den Hollander J.
Published: March 2011

A study was made to determine the extent of morphological variation in Planococcoides jalensis (Laing), the most important mealybug vector of cocoa swollen shoot virus (CSSV) in West Africa, and to resolve if more than one Planococcoides species is present. Fourteen populations of P. njalensis collected on cocoa from different localities in Ghana and one population each on Gliricidia sepium (Jacq.) Steud and Coffea canephora Pierre were compared by measured and meristic female characters using two types of morphometric analysis, Discriminant Functional Analysis and Principal Component Analysis. The analyses showed that P. njalensis exhibited a wide range of intraspecific morphological variation, particularly in meristic characters, but failed to identify new Planococcoides species. The results are discussed in relation to the control of the mealybug vectors of CSSV and to the suitability of Gliricidia as a shade tree for cocoa.
Substrate dependent larval development and emergence of the mushroom pests Lycoriella auripila and Megaselia halterata
Authors: Scheepmaker J. W. A. , Geels F. P. , VAN Griensven L. J. L. D. , Smits P. H.
Published: March 2011

Pasteurized, spawned, full‐grown and immediately‐cased full‐grown compost were simultaneously exposed to natural populations of the mushroom pests Lycoriella auripila (Winnertz) (Diptera: Sciaridae) and Megaselia halterata (Wood) (Diptera: Phoridae). Different numbers of adults emerged from each of these composts. Highest numbers of L. auripila emerged from spawned and pasteurized compost whereas lowest numbers of L. auripila emerged from full‐grown compost. The emergence from full‐grown compost was delayed, which could be explained by the delayed development of the larvae in this type of compost. High numbers of M. halterata emerged from compost that was completely colonized by the mycelia of the edible white button mushroom Agaricus bisporus (Lange) Imbach. The immediate covering of the compost with a casing layer significantly lowered the numbers of emerging M. halterata flies. Compared with the emergence pattern from full‐grown and immediately‐cased full‐grown compost, adult M. halterata showed a delayed pattern of emergence in spawned compost. Adult M. halterata did not emerge from pasteurized compost. The results of these experiments enabled us to improve the timing of the application of insect pathogenic nematodes in the control of the larvae of both insect pests.
Methyl jasmonate‐induced nicotine production in Nicotiana attenuata: inducing defenses in the field without wounding
Authors: Baldwin Ian T.
Published: March 2011

The functional significance of herbivore‐induced plant traits known to directly or indirectly influence herbivore performance remains largely untested under field conditions due to the difficulty of uncoupling the response to herbivory from the act of herbivory. The signals that activate many of the induced responses in plants are endogenously produced in response to wounding, unlike many of the predator‐induced responses found in aquatic invertebrates (which are activated by exogenous cues derived from predators). Jasmonates, endogenously‐produced damage signals, activate diverse wound‐induced responses in plants including induced nicotine production in Nicotiana sylvestris. The results presented here are from two experiments which illustrate the use of jasmonates to uncouple induced nicotine production in Nicotiana attenuata (Torrey ex. Watson) from wounding. The exogenous addition of methyl jasmonate (MJ) in small quantities (11 μg for a 1.4 g dry mass plant) to roots of hydroponically‐grown plants induces de novo nicotine synthesis and increases whole‐plant nicotine concentrations just as wounding does. The MJ‐induced changes were proportional to the quantity of MJ given. Moreover, the effects of MJ were additive to the effects of damage. Applications of MJ to shoots were less effective. Root treatments also worked with plants growing in a field plot. The application of MJ represents a promising tool for examining the functional significance of induced nicotine responses in plants growing in their native environments.
Effect of CryIC toxin from Bacillus thuringiensis on larval feeding behavior of Spodoptera exigua
Authors: Berdegué Mariano , Trumble John T. , Moar William J.
Published: March 2011

The lack of data on the effect of Bacillus thuringiensis (B.t.) toxins on larval feeding behavior of the pest Spodoptera exigua (Hübner) (Noctuidae: Amphypyrini) prompted us to investigate the effect of three delivery systems of CryIC, a commercial formulation, inclusion bodies, and the activated CryIC toxin. The commercial formulation was the least and CryIC toxin the most lethal form to neonates of susceptible colonies. All but two of the treatments in choice tests with neonates and third instars showed significant avoidance of B.t. treated diet, with greater proportion of larvae from susceptible (UCR‐S and AUBURN‐S) and resistant (AUBURN‐R) colonies on untreated diet than on diet treated with any of the CryIC forms and concentrations tested. Furthermore, third instars consumed significantly more control than treated diet for all CryIC forms, colonies and concentrations. The avoidance of CryIC toxin by neonates and third instars strongly suggests that CryIC, which also is present in the commercial formulation and in the inclusion bodies, is responsible for eliciting avoidance behavior by S. exigua larvae. Behavioral observations of third instars in a no‐choice test on either treated or control diet indicated that questing behavior in susceptible larvae appears to be positively related with presence of CryIC toxin in the diet. Furthermore, resistant third instars were on the whole more active than susceptible thirds on both treated and control diet. Resistant thirds raised on CryIC treated diet (AUBURN‐RC) spent more time eating treated diet than resistant larvae raised on control diet (AUBURN‐R), suggesting that diet conditioning plays an important role on feeding behavior of S. exigua. The implications of these results are discussed.
Effects of natural and synthetic neuroactive substances on the growth and feeding of cabbage looper, Trichoplusia ni
Authors: Heinz Cheryl A. , Zangerl Arthur R. , Berenbaum May R.
Published: March 2011

In this study we investigated the effects of two naturally occurring beta‐carboline alkaloids and two synthetic tricyclic antidepressants on the growth and food consumption of fifth instar larvae of the cabbage looper, Trichoplusia ni Hübner (Lepidoptera: Noctuidae). In artificial diets at high concentrations (3,000 ppm), harmane, amitriptyline, and imipramine reduce growth and feeding; harmane reduced feeding consistently at a lower concentration (200 ppm). In animals other than insects, beta‐carboline alkaloids inhibit monoamine oxidase (MAO) activity and thus affect rates of disposition of serotonin and other monoamine neurotransmitters. Because brain serotonin levels are associated with variation in rates of carbohydrate and protein intake in insects, the effects of beta‐carboline alkaloid ingestion on dietary self‐selection behavior were examined. Choosing between diets lacking carbohydrate but containing protein and diets lacking protein but containing carbohydrate, larvae consumed a greater proportion of diet containing protein but lacking carbohydrate in the presence of harmane than in its absence. These results are consistent with beta‐carboline alkaloid‐mediated persistence of serotonin in the brain due to MAO inhibition. Alternatively, these results could reflect alkaloid‐mediated peripheral inhibition of sucrose taste receptors influencing ingestive behaviors. That beta‐carboline alkaloid ingestion is associated with changes in feeding behavior is consistent with a possible defensive role for these compounds in plant foliage.
Fitness comparison between clones differing in their ability to produce sexuals in the aphid Rhopalosiphum padi
Authors: Rispe Claude , Simon Jean‐Christophe , Pierre Jean‐Sébastien
Published: March 2011

This study aimed at evaluating the intrinsic rate of increase (rm) of clones of the cereal aphid Rhopalosiphum padi (L.) that differ in their ability to produce sexuals. The value of rm was measured for wingless parthenogenetic females in experiments conducted at two temperatures (15 °C and 20 °C). We studied six holocyclic clones, five androcyclic clones and five anholocyclic clones and showed that life‐cycle has no significant effect on the age at first reproduction, on fecundity nor on longevity. As a result there is no influence on (summer) fitness: on the one hand, holocyclic clones do not compensate their lower fitness in mild winters by a higher fitness during the summer. On the other hand, anholocyclic and androcyclic clones do not seem to obtain any advantage from living on a more restricted range of hosts: there appears to be no cost of polyphenism for holocyclic clones.
Demographic study of the reproductive potential of pear psylla,Cacopsylla pyri
Authors: Kapatos E. T. , Stratopoulou E. T.
Published: March 2011

Longevity and fecundity of pear psylla adults,Cacopsylla pyri(L.) (Homoptera: Psyllidae), were studied in Greece under field conditions, during 1991/92 and 1992/93. Net fecundity (mean fecundity of cohort) of the overwintered females (winter form) was low (24.1 and 43.4 eggs per female for 1991/92 and 1992/93 respectively) because only a small fraction of the females survive reproductive diapause. Surviving females, however, are capable of producing a relatively high number of eggs (135.0 and 151 9 eggs per female for the two seasons respectively). Net fecundity of summer form females was very high in spring (343.2 and 406.8 eggs per female for 1992 and 1993 respectively), relatively high in early autumn (130.4 and 192.5 eggs per female) and very low in summer (21.9 and 46.5 eggs per female). Male longevity was in all cases shorter than that of female. Longevity of both sexes of the summer form was higher in spring and autumn (for females it ranged from 22.3 to 28.4 days) than it was in summer (for females it ranged from 14.3 to 17.4 days).
Fitness of the hover flies Episyrphus balteatus and Eupeodes corollae faced with limited larval prey
Authors: Rojo Santos , Hopper Keith R. , Marcos‐García M. Angeles
Published: March 2011

Differences in adult oviposition behavior of the aphidophagous hover flies Episyrphus balteatus (De Geer) and Eupeodes corollae (F.) (Diptera: Syrphidae) led us to formulate and test hypotheses concerning their larval behaviour. In laboratory experiments, larval E. balteatus lived longer when starved than larval E. corollae, and this difference increased with age at which starvation commenced. Larval E. balteatus crawled faster than larval E. corollae, and this difference increased under starvation. Limited aphid supply reduced larval and pupal survival more for E. corollae than for E. balteatus. However, the effect of limited aphid supply on adult body size did not differ for the two species. E. balteatus oviposition and larval behavior make it a more promising candidate for introducing to control Diuraphis noxia (Mordwilko) (Homoptera: Aphididae) where this aphid has become an exotic pest.
Effect of cocoa pod age on egg distribution and egg parasitism of the cocoa pod borer in Malaysia
Authors: Azhar I. , Long G. E.
Published: March 2011

The effects of pod age on oviposition, and on egg and larval survival of the cocoa pod borer (CPB), Conopomorpha cramerella (Snellen), were investigated. CPB were allowed to oviposit on a batch of 50 pods for a period of 7 days over several exposure dates. Numbers of CPB eggs/pod and survival to larval emergence from the pods were recorded. Pods were harvested when ripe and analyzed for larval survival within the pod. The oviposition pattern varied with pod age. Older pods less than 7 weeks before ripening (WBR) were preferred, suggesting greater nutritional value or chemical attraction of the older pods. The proportion of eggs parasitized by Trichogrammatoidea bactrae fumata Nagaraja (TBF), the number of eggs lost and the proportion surviving to larval emergence from the pod were independent of pod age. Egg parasitism was low, implying that TBF was not an effective natural enemy. Mass‐releases of TBF should be intensified during cropping periods with higher proportions of susceptible pods (<10 WBR). Survival of larvae in the presclerotic layer (preSCL) was high and independent of pod age. Larval mortality at the SCL (sclerotic layer) was dependent on pod age and was high in older pods. Larval density influenced the survival of larvae inside the pod and was dependent on pod age. Larval mortality associated with SCL hardness and thickness is one of the criteria for the selection of CPB resistant cocoa clones.
Behavioral responses in prey location of the predatory stink bug, Eocanthecona furcellata, to chemical cues in the larvae of Spodoptera litura
Authors: Yasuda Tetsuya , Wakamura Sadao
Published: March 2011

Behavioral responses of the predatory stink bug Eocanthecona furcellata (Wolff) (Heteroptera: Pentatomidae) towards Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) larvae were observed in olfactometers. In single‐ and dual‐tube olfactometers, adult bugs were observed to approach and stretch their proboscis toward the odor source. These types of behavior were also observed toward the control odor source in the dual‐tube olfactometer. However, the frequency of these phases toward the control odor was significantly lower than that toward the odors from intact or dead larvae. The solvent extracts of larvae elicited these similar behavioral phases significantly more frequently and for significantly longer duration than the control. In a linear track olfactometer, E. furcellata nymphs were observed to be attracted to the fraction eluted with hexane from silica gel chromatography but proboscis‐protruding behavior was not observed. The other fraction, 15%‐ether‐in‐hexane from silica gel chromatography, elicited the proboscis‐protruding behavior by a simple behavioral assay using a Pasteur pipette. These findings therefore indicate the presence of at least two different chemical cues in prey location.
The role of host species, age and defensive behaviour on ovipositional decisions in a solitary specialist and gregarious generalist parasitoid (Cotesiaspecies)
Authors: Brodeur Jacques , Geervliet Jacqueline B. F. , Vet Louise E. M.
Published: March 2011

The main objective of this study was to determine the extent to which host acceptance behaviour as related to host species, age, and defensive behaviour might explain the differences in host use that exist between two congeneric and sympatric species of parasitic wasps.Cotesia glomerata(L.) (Hymenoptera: Braconidae) is gregarious and generalist on several species of Pieridae, whereasC. rubecula(Marshall) is solitary and specific toPieris rapae(L.).Cotesiaspecies differed in their responses to host species (P. brassicae (L.),P. napi(L.) andP. rapae) and developmental stage (early and late 1st, 2nd and 3rd instars). In no‐choice tests, host acceptance byC. rubeculawas higher forP. rapaeand females did not distinguish among the 6 host ages. In contrast, when foraging forP. brassicaeandP. napi, C. rubeculafemales more readily attacked early first instar.Cotesia glomeratashowed a higher degree of behavioural plasticity towards acceptance ofPierishost species and host age than didC. rubecula. Cotesia glomeratafemales parasitized the threePierisspecies and showed higher acceptance of first and second instars over third instar. Oviposition success was also influenced by host defensive behaviour. The frequency and the effectiveness of defensive behaviour rose with increasing age of the host,P. brassicaebeing the most aggressivePierisspecies. Furthermore, the mean duration ofC. glomerataoviposition was significantly reduced by the defensive reactions ofP. brassicae, which would likely affect parasitoid fitness as oviposition time is positively correlated to clutch size inC. glomerata.Acceptance frequencies corresponded well to field reports ofPieris‐Cotesiaassociations and to patterns of parasitoid larval performance, suggesting that the acceptance phase might be used as a reliable indicator ofCotesiahost‐specificity.
Determination of the toxicity of faeces of cattle treated with an ivermectin sustained‐release bolus and preference trials using a dung fly,Neomyia cornicina
Authors: Gover Jane , Strong Les
Published: March 2011

The toxicity of dung from cattle treated with an ivermectin sustained‐release bolus was estimated in terms of ivermectin or ivermectin equivalents, using a laboratory bioassay with the dung flyNeomyia cornicinaFabricius (Diptera, Muscidae). The mortalities of flies measured 7 days after feeding for 24 h on dung containing known concentrations of ivermectin (between 0.125 and 1 μg ivermectin per gram fresh dung) were compared with the mortalities of insects fed for 24 h on dung from cattle treated 21 days previously with an ivermectin sustained‐release bolus. The toxicity of the bolus dung was equivalent to dung containing 0.66 μg ivermectin per gram fresh dung. To determine whether insects could differentiate between control dung and dung from bolus‐treated cattle, choice‐chamber tests were carried out. There was no significant difference in the percentage of females that chose either dung type, suggesting that they were unable to distinguish the dung of bolus‐treated cattle from control dung. Results are discussed in relation to the impact that bolus use can have on the insect fauna of cattle dung.
Effects of honeydew and insecticide residues on the distribution of foraging aphid parasitoids under glasshouse and field conditions
Authors: Longley Martin , Jepson Paul C.
Published: March 2011

The opposing effects of attraction to host‐derived kairomones and repellency from the pyrethroid insecticide deltamethrin were investigated with aphid parasitoids from the genus Aphidius (Hymenoptera: Aphidiinae). The spatial distribution of female parasitoids was recorded in a series of experiments conducted in a small glasshouse containing wheat plants either infested with cereal aphids, Sitobion avenae (F.) (Homoptera: Aphididae), uninfested or treated with the recommended field concentration of deltamethrin. The number of parasitoids per plant were counted at 0.5 h, 1 h and then at one hourly intervals up to 8 h after release. Parasitoids showed a strong aggregation response to aphid‐infested plants compared to adjacent uninfested plants. With the introduction of insecticide‐treated plants around the aphid‐infested plants, parasitoids showed a greater tendency to disperse away, resulting in fewer parasitoids on plants and significantly lower rates of aphid parasitism. The degree of aphid fall‐off from plants was a good indicator of parasitoid foraging activity. In field studies, using sticky traps to measure the activity of parasitoids in plots sprayed with water, deltamethrin and/or an artificial honeydew solution, repellent properties were evident for up to 2 days after application. The attraction/arrestment stimuli associated with the honeydew solution were sufficient for parasitoids to continue searching insecticide‐treated areas. The implications of these findings for parasitoids searching crops contaminated with aphid‐derived kairomones and insecticides are discussed.
Secondary host choice by the autoparasitoid Encarsia pergandiella
Authors: Pedata Paolo A. , Hunter Martha S.
Published: March 2011

Autoparasitoids are species of parasitic wasps in the family Aphelinidae which produce females as solitary primary endoparasitoids of homopterans such as whitefly and scale insects (‘primary hosts’), and males as solitary hyperparasitoids. Males generally develop on immature conspecific females or on individuals of other primary parasitoid species (‘secondary hosts’). Encarsia pergandiella is an autoparasitoid that has been introduced to Italy for control of greenhouse whitefly Trialeurodes vaporariorum, in greenhouses and field crops. In this study we examined the secondary host selection behaviour of this species with regard to conspecific females and females of two thelytokous species, E. formosa and E. meritoria. Encarsia formosa has been used successfully for greenhouse whitefly control in Northern Europe, but has not been effective in Southern Italy in winter crops in unheated greenhouses. E. meritoria has recently spread in Italy, and may have potential for biological control of whitefly in the greenhouse environment. In the first experiment, female E. pergandiella were exposed to one of three pair‐wise combinations of the three species in petri dish arenas. Parasitism was determined by dissection of the hosts. The number of hosts parasitized by E. pergandiella females did not differ with host species. However, significantly greater numbers of eggs were laid in E. meritoria in both treatments in which it was present; these hosts were more likely to be superparasitized. In a second experiment, observations of females in arenas with equal numbers of all three host species indicated that females encountered and parasitized all host species with approximately equal frequency, although the length of time females spent in the oviposition posture differed with host species.
A feasible, aesthetic quality evaluation of implant‐supported single crowns: an analysis of validity and reliability
Authors: Hosseini Mandana , Gotfredsen Klaus
Published: March 2011

Objectives: To test the reliability and validity of six aesthetic parameters and to compare the professional‐ and patient‐reported aesthetic outcomes.

Material and methods: Thirty‐four patients with 66 implant‐supported premolar crowns were included. Two prosthodontists and 11 dental students evaluated six aesthetic parameters, the Copenhagen Index Score (CIS): (i) crown morphology score, (ii) crown colour match score, (iii) symmetry/harmony score, (iv) mucosal discolouration score, (v) papilla index score, mesially and (vi) papilla index score, distally. The intra‐ and inter‐observer agreement and the internal consistency were analysed by Cohen's κ and Cronbach's α, respectively. The validity of CIS parameters was tested against the corresponding Visual Analogue Scales (VAS) scores. The Spearman correlation coefficients were used. Six aesthetic Oral Health Impact Profile (OHIP) questions were correlated to the CIS and the overall VAS scores.

Results: The intra‐observer agreement was >70% in 2/3 and >50% in all observations. The inter‐observed agreement was >50% in 4/5 of all observations. The mucosal discolouration score had the overall highest observed agreement followed by the papilla index scores. The crown morphology and the symmetry/harmony scores had the overall lowest agreement. The Cronbach α value was over 0.8 for all observers. All CIS scores demonstrated significant (P<0.0001) correlation to the corresponding VAS scores. Low correlation coefficients (CIS/OHIP: rs<0.36; VAS/OHIP: rs >−0,24) were found between patient and professional evaluations.

Conclusions: The feasibility, reliability and validity of the CIS make the parameters useful for quality control of implant‐supported restorations. The professional‐ and patient‐reported aesthetic outcomes had no significant correlation.

To cite this article: Hosseini M, Gotfredsen K. A feasible, aesthetic quality evaluation of implant‐supported single crowns: an analysis of validity and reliability. Clin. Oral Impl. Res. 23, 2012 453–458. doi: 10.1111/j.1600‐0501.2011.02162.x
Accuracy assessment of cone beam computed tomography‐derived laboratory‐based surgical templates on partially edentulous patients
Authors: Behneke Alexandra , Burwinkel Matthias , Knierim Kristian , Behneke Nikolaus
Published: March 2011

Objectives: The aim of the present prospective clinical study was to evaluate the match between the positions and axes of the virtually planned and the placed implants using laboratory‐based surgical guides generated from cone beam computed tomography (CBCT).

Materials and methods: A total of 132 implants were placed with the aid of 3D‐based transfer templates in 52 consecutive partially edentulous patients between April 2008 and March 2010. After individual adaptation of the scan templates and CBCT scanning, the acquired data for virtual implant planning and simulation were processed using the med3D software program. After finalizing the virtual placement of the implants the radiographic templates were converted into operative guides containing titanium sleeves for cavity preparation. Preoperative planning was merged with postoperative CBCT data to identify linear and angular deviations between virtually planned and placed implants.

Results: Compared with the planned implants the installed implants showed linear deviations in the median at the neck and apex of 0.27 mm (range 0.01–0.97 mm), and of 0.46 mm (range 0.03–1.38 mm), respectively. The angle deviation was 1.84° in median, with a range of 0.07–6.26°. The extent of deviation depends on the size of the tooth gap and the distribution of the remaining teeth.

Conclusion: The results of this study suggested that laboratory‐fabricated surgical guides using CBCT data may be reliable in implant placement under prosthodontic considerations in partial edentulism.

To cite this article: Behneke A, Burwinkel M, Knierim K, Behneke N. Accuracy assessment of cone beam computed tomography‐derived laboratory‐based surgical templates on partially edentulous patients. Clin. Oral Impl. Res. 23, 2012; 137–143.  doi: 10.1111/j.1600‐0501.2011.02176.x
Effect ofAscaridia comparinfection on rock partridge population dynamics: empirical and theoretical investigations
Authors: Rosà R. , Bolzoni L. , Rosso F. , Pugliese A. , Hudson P. J. , Rizzoli A.
Published: March 2011

Helminth parasites have the potential to significantly affect the dynamics of their hosts. As a consequence, they can dramatically threaten the persistence of endangered species, such as rock partridgeAlectoris graeca saxatilis, found in the Province of Trento (northern Italy).

The aim of this work was to understand the effect of helminth parasites on rock partridge fitness, and the subsequent potential effects on host population dynamics. In particular, we investigated the hypothesis that infections fromAscaridia comparinduce rock partridge population cycles observed in Trentino. In order to support this hypothesis, we compared the predictions obtained from a host–parasite interaction model including variable parasite aggregation with multi‐annual empirical data ofA. comparinfection in natural host populations. We estimated host demographic parameters using rock partridge census data from Trentino, and the parasitological parameters from a series of experimental infections in a captive rock partridge population. The host–parasite model predicted higherA. comparabundance in rock partridge populations exhibiting cyclic dynamics compared to non‐cyclic ones. In addition, for cyclic host populations, the model predicted an increase in mean parasite burden with the length of cycle period. Model predictions were well‐supported by field data: significant differences in parasite infection between cyclic and non‐cyclic populations and among cyclic populations with different oscillation periods were observed.

On the basis of these results, we conclude that helminth parasites can not be ruled out as drivers of rock partridge population dynamics in Trentino and must be considered when planning conservation strategies of this threatened species.
Facing up to the imperceptible perspiration. Modulatory influences by diabetic neuropathy, physical exercise and antiperspirant
Authors: Xhauflaire‐Uhoda Emmanuelle , Mayeux Géraldine , Quatresooz Pascale , Scheen André , Piérard Gérald E.
Published: March 2011

Background: Sweating is variably altered by physical exercise, diabetic neuropathy and antiperspirants.

Methods: Skin temperature, skin surface water loss (SSWL), the Corneometer® average capacitance (CMAC) and skin capacitance mapping (SCM) were measured before and after moderate physical exercise in 20 healthy subjects. The effect of 5% aluminium chloride hexahydrate (ACH) in a water solution was similarly tested. The same assessments were performed in 20 diabetic patients at rest.

Results: Diabetic neuropathy appeared at rest as an increased (compensatory) SCM on the forearms without obvious modification on the hypohidrotic legs. On ACH sites after exercise, SCM revealed both a lowered number of active sweat glands and a lighter stratum corneum (SC) (dryness). In addition, CMAC and SSWL were decreased on ACH sites at rest and at completion of exercise.

Conclusion: In diabetic neuropathy, the compensatory hyperhidrosis is more easily disclosed than the hypohidrosis. ACH affects both sweat excretion and the SC hydration.