bluuebunny/crossref_metadata_2025 huggingface dataset:
Alkaloid level in narrow‐leafed lupin, Lupinus angustifolius, influences green peach aphid reproductive performance
Authors: Berlandier Françoise A.
Published: March 2011

Two viviparous parthenogenetic clones of the green peach aphid, Myzus persicae (Sulzer), one collected from Rydalmere, New South Wales (NSW), and the other from South Perth (SP), Western Australia, were reared on radish, Raphanus sativus L. cv. Scarlet Globe, under controlled conditions. The NSW clone was fed on simple artificial diets containing alkaloid extracted from narrow‐leafed lupin, Lupinus angustifolius L. cv. Fest., and its reproductive performance monitored over 112 h. Forty (40) h into the experiment and thereafter, aphids on the control diet (sucrose solution) produced significantly more offspring (P<0.05) than those on diets containing alkaloid. In a separate experiment, apterae of each clone were caged on three lines (cv. Yorrel, cv. Danja and 84L:441) of narrow‐leafed lupin, and allowed to reproduce. The first three offspring were retained, and all developed to 3rd or 4th instar stage. Two nymphs were removed, and the remaining nymph reared through. All three lines produced adults. The number of young produced were counted over 11 days. Fecundity of the SP clone was lower on line 84L:441, but there was no difference in the fecundity of the NSW clone. Phloem exudate and green tissue was concomitantly collected from all lines, and analysed by GC‐MS for the alkaloids lupanine and 13‐hydroxylupanine. Line 84L:441 contained the highest level of total alkaloids in both phloem and tissue. All experiments indicate that alkaloid level may suppress fecundity of green peach aphids.
The structure of the phytophagous insect fauna on the introduced weed Solidago altissima in Switzerland
Authors: Jobin A. , Schaffner U. , Nentwig W.
Published: March 2011

Solidago altissima L. was introduced into Europe as an ornamental plant from North America more than 100 years ago and the phytophagous insect fauna of it was recently examined in Switzerland where it has become an important weed in disturbed habitats. Rhizomes and aerial parts were examined and all insects collected in summer were tested in a no‐choice feeding test. 18 out of 55 phytophagous insects were found feeding on S. altissima in Switzerland and for the remaining 37 the relation with the plant was not determined. The insects that have expanded their host range to feed on S. altissima since its introduction to Switzerland are almost solely opportunistic, unspecialized ectophages not closely attuned to the growth cycle of S. altissima. Only 4% of the insects were specialists and 9% endophagous. In contrast in North America S. altissima supports 25% specialists and 17% endophages. The native Solidago virgaurea L. in Switzerland supports many more specialists (28%) and endophages (23%) than S. altissima here. Possible reasons why almost none of these have switched to S. altissima are discussed. A comparison is made between the number of insects recruited by S. altissima in Switzerland with the number recruited by the exotic plants Heracleum mantegazzianum Som. & Lev. (Apiaceae) in Switzerland and Xanthium occidentale Bertol. (Asteraceae) in Australia. Reasons for different levels of insect recruitment are discussed. The high number of phytophagous insect species found on S. altissima in North America shows that there should be no shortage of possible control agents and any insects imported into Switzerland for the biological control of S. altissima would find largely unexploited food sources awaiting them.
Effects of heavy metal stress on free amino acids in the haemolymph and proteins in haemolymph and total body tissue of Lymantria dispar larvae parasitized by Glyptapanteles liparidis
Authors: Bischof Claudia
Published: March 2011

Heavy metal contamination of the forest pest insect Lymantria dispar (L.) (Lepidoptera; Lymantriidae), the gypsy moth, can alter its haemolymph composition, as has already been shown for carbohydrates and lipids in recent studies. L. dispar larvae are frequently parasitized by Glyptapanteles liparidis (Bouché) (Hymenoptera; Braconidae) larvae, which can — to some extent — regulate the population size of the pest insect. The parasitoids feed on the haemolymph of L. dispar larvae; hence, a different haemolymph composition of the host alters the trophic situation of the parasitoids. The aim of the present study was to investigate whether metal contamination also affects the concentrations of free amino acids in L. dispar haemolymph, and protein concentrations in their haemolymph and tissue. L. dispar larvae were parasitized on the first day of the second instar and then reared on diets contaminated with Cd, Pb, Cu or Zn at two concentrations each. Haemolymph and total body tissue of the larvae (fourth instar/third day) were analyzed. The concentrations of the free amino acids were elevated in five out of the eight contamination groups (Cd6, Pb4, Cu6, Cu10, Zn60), whereas haemolymph protein concentrations were significantly reduced in all contaminated individuals. The haemolymph protein concentration was 18 mg/ml in the control group and decreased to less than 10 mg/ml due to cadmium and zinc contamination at both concentrations and in the low copper contamination group. In contrast, total body proteins (136 μg/mg dry weight in the control group) were elevated due to heavy metal stress. Analyses of haemolymph protein concentrations during the fourth instar demonstrated an increase of the proteins from day one to day four (followed by a decrease on the fifth day) in the control group and the cadmium contamination group. A steady increase of proteins from the first to the fifth day in the copper and zinc contaminated larvae indicated a retarded development in these groups. Thus, the present study along with other recent studies demonstrated, that heavy metal stress changes the concentrations of all main haemolymph compounds of L. dispar larvae.
Stylet penetration by larvae of the greenhouse whitefly on cucumber
Authors: Lei H. , Tjallingii W. F. , VAN Lenteren J. C. , Xu R. M.
Published: March 2011

Probing behaviour of Trialeurodes vaporariorum (Westwood) larvae was monitored using the DC electrical penetration graph (EPG) technique on the host plant cucumber. EPGs were recorded for 16 h, simultaneously with honeydew excretion using a ‘honeydew clock’. Three waveforms were distinguished: a pathway waveform (C), and two phloem waveforms, one with a high (H), and one with a low frequency (L) signal. The C waveform mainly occurred in the crawler stage of the 1st instar larvae. EPGs recorded from larvae during and after moulting indicated that the process involves stylet withdrawal; hence the stylets of each new instar need to penetrate again from the leaf surface to the phloem.

All sessile stages, from L1 to pre‐pupa, spent almost their entire time in waveforms H and L. These waveforms alternated more frequently in the early instars than during the later ones, in which the H waveform became predominant. The H waveform was highly correlated with honeydew excretion and thus phloem sap ingestion. The L waveform was not related to honeydew excretion but EPGs indicated that the stylet tips remain in a sieve element during both waveforms. Periods of honeydew production demonstrated a delay of 30–40 min in relation to the onset and end of H and L waveforms. This delay is presumably related to the time needed for food passing through, or emptying of, the insect's gut. From the 1st instar to the pre‐pupa, the frequency of excreted honeydew droplets decreased but their size increased, causing a net increase of the excretion rate.
Mate recognition in the Aphis fabae complex: daily rhythm of release and specificity of sex pheromones
Authors: Thieme T. , Dixon A. F. G.
Published: March 2011

The two subspecies of the host‐alternating black bean aphid, Aphis fabae Scopoli, used in this study have different secondary host plants but reproduce sexually in autumn on the same host plant, spindle, Euonymus europaea L. In both Aphis fabae fabae Scopoli and A. f. solanella Theobald the percentage of adult mating females (oviparae) calling (releasing sex pheromone) each day increased with age up to day 8. During the course of a day the mating females of A. f. solanella called most actively early in the morning and then showed a gradual decrease in calling activity. In contrast, few A. f. fabae called early in the day and were most active around midday, after which the incidence of calling decreased slightly, with 50% still calling in the evening. In both taxa the activity of the males in the absence of mating females paralleled the calling activity of their respective females. In an olfactometer, males showed a marked preference for the sex pheromone released by conspecific females over that of the other subspecies and did not respond to the odour of spindle. Thus, as in the other species of aphids there are specific mate recognition systems in A. f. fabae and A. f. solanella, which are likely to reduce the incidence of hybridisation.
Foraging behaviour and resource utilization of the aphid parasitoid Pauesia unilachni: adaptation to host distribution and mortality risks
Authors: Völkl Wolfgang , Kraus Werner
Published: March 2011

Pauesia unilachni is a parasitoid of the grey pine aphid, Schizolachnus pineti which feeds on needles of Scots pine. P. unilachni females displayed a ‘dual movement system’ when foraging within a pine. They left a colony usually by foot and searched nearby needles intensively, thereby ensuring a maximum probability to encounter neighbouring S. pineti colonies. If search by foot was not successful, parasitoids changed their behaviour and searched needles by flight to cover larger distances. This behaviour was consistent both on uninfested and S. pineti‐infested trees in the laboratory and in the field. In total, females allocated a 15‐fold amount of time into search by foot compared to search by flight, although the overall foraging success, i.e. the number of discovered host colonies, did not differ significantly between the two movement types. However, the reduction of searching time by flight involved also higher travel mortality risks. In the field, P. unilachni got frequently entangled in spider nets when searching by flight and were killed.
Effects of adult chill treatments on mate attracting potential for irradiated Mexican fruit fly males
Authors: Mangan Robert L.
Published: March 2011

Mexican fruit flies, Anastrepha ludens (Loew), that are reared, sterilized and released for maintenance of a fly free zone in south Texas and for population eradication in California are routinely chilled for 1 to 2 h to facilitate handling and dispersal. While a number of behavioral, physical and physiological characteristics are routinely monitored as part of a quality control program, the effect of the chilling process on the ability of these males to attract wild females has not been evaluated. Tests were performed to compare the mate attracting effectiveness of mass reared, sterilized, chilled males with sterile males that had not been chilled and with recently colonized males. Tests were performed with two recently colonized strains of females in a large cage and males of the three types in plastic cups set on top of the cage. Controls consisted of empty cups. Results showed no significant differences among the three types of males. In tests with the most recently collected (least laboratory adapted) wild strain of females, the chilled males attracted the most females. Fly age and time of day were both significantly related to total attractiveness of males. Number of females responding to males per day increased over the five‐day test period. The time period when female response was greatest was variable among the tests.
Effect of neem on the growth and development of the obliquebanded leafroller, Choristoneura rosaceana
Authors: Lowery D. T. , Bellerose S. , Smirle M. J. , Vincent C. , Pilon J.‐G.
Published: March 2011

Neem, Azadirachta indica A. Juss. (Meliaceae), seed oil (NSO) added to meridic diet at concentrations as low as 0.016% reduced pupation and prevented adult eclosion of obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae). At a rate of 0.0016%, NSO reduced the fitness of C. rosaceana, resulting in longer developmental times, lower adult eclosion rates, and reduced egg production compared with controls. The neem insecticide Margosan‐TM produced comparable results based on concentrations of the most biologically active constituent, azadirachtin. Pupation was completely inhibited at concentrations of 0.25% and 1.0% for larvae exposed at 5th or 6th instar, respectively; rates as low as 0.016% reduced pupal weights and adult eclosion rates. For larvae transferred to treated diet at 5th instar, physical abnormalities in the wings of adults occurred at a rate of 0.004% NSO and increased with increasing treatment rates. NSO at concentrations as high as 2.0% was not antifeedant to neonate larvae, based on 24 and 48 h choice test bioassays, when incorporated into a meridic diet.
Bruchid resistance of transgenic azuki bean expressing seed α‐amylase inhibitor of common bean
Authors: Ishimoto Masao , Sato Takashi , Chrispeels Maarten J. , Kitamura Keisuke
Published: March 2011

Various species of bruchid beetles including Callosobruchus chinensis, C. maculatus and C. analis cause post‐harvest damage of azuki bean seeds, an important East Asian grain legume. The α‐amylase in the midguts of these insects is inhibited by the α‐amylase inhibitor (αAI) present in common bean seeds. Transformation of azuki bean with the αAI gene driven by the promoter of phytohemagglutinin results in high levels of αAI in the seeds and the complete block of bruchid development on the seeds. Zabrotes subfasciatus, a South and Central American bruchid that is a storage pest of common bean, develops normally on the transgenic azuki bean.
Electrical recording of plant penetration by western flower thrips
Authors: Harrewijn P. , Tjallingii W. F. , Mollema C.
Published: March 2011

Plant penetration by western flower thrips (Frankliniella occidentalis (Pergande)) was analysed with the electrical penetration graph technique (EPG, DC‐system). Thrips attached to a gold wire were included in an electrical circuit to record EPGs when penetrating the plant tissues with their stylets. Three basic EPG waveforms have been distinguished, correlated with stylet penetration into cells, salivation, and ingestion, respectively. The main difference with EPGs of Homoptera is the occurrence of continued separate penetrations that are not necessarily followed by ingestion. Insertion of the stylets causes strong voltage fluctuations in the EPG. We could confirm earlier evidence that penetration of cells and subsequent ingestion of (part of) the protoplast takes less than 20 seconds. Repeated short penetrations can be followed by a continuous feeding pattern during which the stylets are not withdrawn. The same sequence of waveforms is produced on other plant parts such as fruits or pollen grains. The specific waveforms are mainly caused by electromotive force (emf). The emf component was recorded with high resolution and the correlation of waveform details with activities of the cibarial muscle system is discussed.
Avoidance of willows from moderately polluted area by leaf beetle, Melasoma lapponica: effects of emission or induced resistance?
Authors: Zvereva Elena L. , Kozlov Mikhail V.
Published: March 2011

We studied preference for willows along a pollution gradient on the Kola Peninsula, Russia, by the leaf beetle, Melasoma lapponica. Multiple tests with leaf disks demonstrated low preference for Salix borealis, S. caprea and S. phylicifolia from the plot situated 14 km from the smelter, in comparison with conspecific plants from plots situated at 1 and 29 km distances. This pattern was observed when testing beetles orginating from any plot both in 1993 and 1994, using both young and mature leaves of S. borealis. Although fumigation of S. borealis with realistic SO2 concentration (100 μg/m3) increased plant palatability, preference for plants from our study plots did not correlate with plot‐specific mean SO2 concentrations. Furthermore, no correlation with foliar concentrations of the main metal pollutants (Ni and Cu) was found. Palatability of plants was negatively correlated with population density of M. lapponica, which peaked in the moderately polluted plot 14 km from the smelter. Within this plot, beetles clearly preferred non‐damaged bushes of S. borealis to previously damaged bushes. We therefore conclude that low preference of S. borealis from the moderately polluted area was caused by plant resistance induced by severe damage from M. lapponica in previous years rather than by pollution impact. However, S. caprea and S. phylicifolia had little damage from M. lapponica, and low palatability of these species in the moderately polluted plot suggests changes in plant quality similar to changes in heavily damaged bushes of S. borealis.
Selective attention and host‐plant specialization
Authors: Bernays E. A.
Published: March 2011

The importance of attentional processing is summarized, and the different ways in which selective attention is maintained, explained. Examples from arthropods are highlighted. The significance of selective attentiveness for insect herbivores is discussed. In the finding and selecting of host plants, insects should adopt the strongest or most clear‐cut cues that override noise, and they should channel the appropriate sensory information efficiently. It is argued that achieving this end is difficult and costly because the information capacity of the sensory system is far greater than the capacity of the central nervous system to process it. It is suggested that the need to obtain a clear signal quickly and efficiently may be one of the factors favoring reduced diet breadth, and that the existence of highly specific and sensitive receptor neurons is an adaptation to the information‐processing problem.
Host‐plant relationships of lycaenid butterflies: large‐scale patterns, interactions with plant chemistry, and mutualism with ants
Authors: Fiedler Konrad
Published: March 2011

The Lycaenidae are the second‐largest family of butterflies. From host‐plant data collated for more than 1200 species worldwide, large‐scale taxonomic, geographical and ecological patterns emerge which suggest that phytochemical similarities and barriers, coupled with phylogenetic conservatism and constraints are key factors governing host‐plant use. More than two thirds of the lycaenid species are restricted to one plant family or genus. Affiliations with ‘toxic’ plants are rare in the Lycaenidae, and excretion rather than sequestration of plant toxins appears to be their usual way of detoxifying host‐plant compounds. Flavonoids are frequently sequestered by lycaenid larvae and are subsequently concentrated as pigments in the adults' wings, where they might play a role in visual communication. Mutualistic associations with ants occur in the larvae of more than 50% of the extant Lycaenidae species. Because of a conflict between the nutrient demands of the larvae and the proportion of plant‐derived resources allocated to maintain the mutualism with ants, variation in resource quality often translates into variation of mutualistic capacities of the caterpillars, in particular under nutrient stress.
The suitability of some natural and artificial substrates as oviposition sites for the insidious flower bug, Orius insidiosus
Authors: Richards P. C. , Schmidt J. M.
Published: March 2011

A variety of natural and artificial substrates were tested for their suitability as oviposition sites for the predatory anthocorid bug Orius insidiosus. The bugs oviposited into models of beans constructed from Parafilm, but none of the eggs laid into these models hatched. In choice tests, beans stems were preferred to both bean pods and potato sprouts. Hatching rates at 100% r.h. were highest (59%) for bean pods and significantly lower for both potato sprouts (39%) and bean stems (29%). At 60% r.h., hatching rates for bean pods (39%), bean stems (34%) and potato sprouts (33%) were similar. At 30% r.h. hatching rates for all three substrates were less than 15%. The results suggest that bean stems can be used successfully as an alternative to bean pods for the mass rearing of these biological control agents.
Effects of neem oil on feeding behaviour and development of the pear sawfly, Caliroa cerasi
Authors: Smirle Michael J. , Wei Shu‐Ge
Published: March 2011

Neem oil deterred feeding by pear sawfly, Caliroa cerasi L., larvae (Hymenoptera: Tenthredinidae), both in choice and in no‐choice cherry leaf disk bioassays. Deterrence was greater in the choice tests, with 50% inhibition occurring at 0.49% aqueous neem oil compared with 1.11% in the no‐choice tests. Antifeedant activity towards pear sawfly larvae is slightly less than has been observed for Lepidoptera, but is higher than deterrence to other insects such as aphids. Topical application of neem oil to sawfly larvae resulted in reduced feeding, increased mortality, and a trend towards slower development. Most larval mortality after neem treatment resulted from incomplete subsequent moults. The potential utilization of neem insecticides for control of pear sawfly in tree fruit pest management is discussed.
Certain withanolides from Iochroma gesnerioides antagonize ecdysteroid action in a Drosophila melanogaster cell line
Authors: Dinan Laurence , Whiting Pensri , Alfonso Dorothée , Kapetanidis Ilias
Published: March 2011

Sixteen withanolides isolated from Iochroma gesnerioides (Kunth) Miers (Solanaceae) have been assessed for their activities as ecdysteroid agonists and antagonists. None of the compounds showed any agonistic activity, but several showed significant antagonistic activity. With a 20‐hydroxyecdysone concentration of 5 times 10−8 M, the ED50 values for 2,3‐dihydro‐3ξ‐methoxywithaferin A, 2,3‐dihydro‐3ξ‐methoxywithacnistine, 2,3‐dihydro‐3ξ‐methoxyiochromolide and 2,3‐dihydro‐3ξ‐hydroxyξwithacnistine are 3.5 times 10−5 M, 1 times 10−5 M, 5 times 10−6 M and 2.5 times 10−6 M, respectively.
Variation between laboratory populations in the performance of the parasitoid Encarsia formosa on two host species, Bemisia tabaci and Trialeurodes vaporariorum
Authors: Henter Heather J. , VAN Lenteren Joop C.
Published: March 2011

We tested the hypothesis that populations of the parthenogenetic parasitic wasp Encarsia formosa Gahan (Hymenoptera: Aphelinidae) differed in their ability to use two different host species, Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) and Trialeurodes vaporariorum Westwood (Homoptera: Aleyrodidae). Of the three wasp populations tested, two populations had been reared for many generations on B. tabaci and one population had been reared for many years on T. vaporariorum. Performance was measured by the number of whitefly nymphs that were successfully parasitized by individual wasps, and performance on either host was measured in separate experiments. There was variation between wasp populations in their performance on the host B. tabaci, with one wasp population reared for many years on this host performing considerably better than the other two populations. There were no significant differences between populations in their use of the preferred host, T. vaporariorum. The experiments were conducted in such a way that we could distinguish heritable differences between populations from environmentally‐induced conditioning differences due to the immediate host from which an individual wasp enclosed. In either experiment there were no significant effects of conditioning, although there was a trend within each population for wasps conditioned on T. vaporariorum to have higher performance than those conditioned on B. tabaci. Thirdly, we conducted a selection experiment, initiated with wasps from a single population historically reared on T. vaporariorum, to measure the effect of laboratory rearing on different hosts for 17 generations. We did not see any difference in the performance of wasps on B. tabaci after this period of rearing on either of the two hosts. In summary, populations of E. formosa do differ in their relative performance on B. tabaci. The one population that was tested further did not show any response to selection by rearing, but the ability to respond to selection on performance may not be equal for all populations. The possibility that wasp populations have differential performance on particular hosts may affect the use of this species as a biological control agent.
Host handling behavior of the egg parasitoid Telenomus triptus to the egg mass of the stink bug Piezodorus hybneri
Authors: Higuchi H. , Suzuki Y.
Published: March 2011

Host handling behavior of Telenomus triptus Nixon (Hymenoptera: Scelionidae) to an egg mass of Piezodorus hybneri Gmelin (Heteroptera: Pentatomidae) was studied in the laboratory. Five distinct behavioral events could be distinguished in the host handling behavior: drumming, ovipositor‐insertion, marking, walking, and resting. Female wasps showed two types of behavioral sequence in an ovipositional bout. One consisted of drumming, ovipositor‐insertion, and marking, and the other drumming, ovipositor‐insertion, walking, and resting. Females did not seem to lay an egg when ovipositor‐insertion was not followed by marking. This was observed frequently in the early oviposition bout, on average 2.9 times per female. Females finally succeeded in parasitizing all the eggs in a host egg mass in most cases. The durations of drumming, ovipositor‐insertion, and marking on an egg mass were nearly constant, while the total time spent by a female on and beside a host egg mass varied considerably as a result of variable durations of walking and resting. Self‐superparasitism occurred when almost all the eggs in a host egg mass were parasitized. Females laid the first male egg within the first four eggs; this could be an adaptation to small egg masses or single egg.
Survival of Bemisia tabaci adults under different climatic conditions
Authors: Berlinger M. J. , Lehmann‐Sigura Nina , Taylor R. A. J.
Published: March 2011

The ability of the sweet potato whitefly, Bemisia tabaci Gennad., to survive a range of environmental conditions was investigated in the laboratory. The range of temperature and humidity investigated corresponds to the normal climatic range during B. tabaci's summer migration in Israel. Adult whiteflies confined to small test cages were exposed to combinations of temperature (25, 30, 35, and 41 °C) and relative humidity (20, 50, 80, and 100%) for periods of 2, 4, or 6 h.

A logistic regression model describing the four‐dimensional surface defining percent survival as a function of time, temperature, and humidity was developed. Using stepwise regression to exclude non‐significant terms, the linear predictor included temperature, and the products of temperature and time, and humidity and time. The model accounted for 75% of the variance. A reparameterization of the fitted regression model suggests that survival potential is conditioned by temperature conditions prevailing during the previous 10 h.

Whitefly survival after 2 h exposure ranged from ∼90% survival at 25 °C and 100% RH, to <2% survival at 41 °C and 20% r.h.∼. No whiteflies survived more than 2 h exposure at these latter extremes of temperature and humidity. Survival rates decreased slightly after experimental whiteflies were kept in a cage with food a further 20 h at 25 ± 2 °C, 55 ± 5% r.h. Investigations of the effects of hunger and virus infection, showed that both increased mortality.
Leaf‐cutting ant preferences for five native tropical plantation tree species growing under different light conditions
Authors: Folgarait Patricia J. , Dyer Lee A. , Marquis Robert J. , Braker H. Elizabeth
Published: March 2011

To examine the susceptibility of five Costa Rican tree species to leaf‐cutter ants (Atta cephalotes L.: Formicidae, Attini), young and mature leaves from trees that were grown in a plantation under full sun and partial shade were offered to six leaf‐cutter colonies located in full sun and six in partial shade. In addition to offering leaf disks to the ants, we offered large pieces of leaves to assess the effect of cutting leaves on food choices. Leaf‐cutters responded differently to each plant species, preferring Virola koschyni Warburg (Myristicaceae) and Hyeronima alchorneoides Allemao (Euphorbiaceae) over Stryphnodendrum microstachyum Poeppig & Endlicher (Mimosoideae), Pentaclethra macroloba Willdenow (Fabaceae) and Vochysia ferruginea Martius (Vochysiaceae). In agreement with previous studies, interspecific differences among the tree species in water and saponin content appeared to account for the observed ant preferences among the five tree species: leaf‐cutter ants preferred leaves and disks with more water and less saponins and the five tree species varied significantly in these traits. An observed positive correlation between preference and phenolic/nitrogen ratio appears to be spurious, and is instead due to a negative correlation between water content and nitrogen content. For the first time, Atta nest location has been shown to affect consumption: nests located in partial shade removed more leaf material than those from the sun plots. However, nest location had no effect on preference ranking of the tree species tested. Pieces of leaves from all the tree species grown in partial shade were significantly more removed than those trees grown in full sun. Leaf age, toughness, leaf specific weights, ant activity, and colony were not correlated with food choices. Because of the observed preferences, the five tree species should not be considered as equal candidates for plantation purposes. However, complete characterization of the candidate status of tree species for plantations in the neotropics must include information on the ability of such species to tolerate pest attacks in addition to their natural defenses to attack.
Orientation responses of the grasshopper, Melanoplus sanguinipes, to visual, olfactory and wind stimuli and their combinations
Authors: Szentesi Árpád , Hopkins Theodore L. , Collins Robert D.
Published: March 2011

Prereproductive adults of the grasshopper, Melanoplus sanguinipes (F.) (Orthoptera, Acrididae), demonstrated orientation and movement towards both visual and olfactory stimulus sources in a still‐air chamber. Visual stimuli (wheat and lima bean foliage, vertical black or yellow‐green stripes, and a yellow‐green broad leaf pattern) were approached more frequently than the control white background surface. Olfactory stimuli (chopped wheat foliage and a four‐component, synthetic, ‘grass odor’ blend of volatiles) elicited an even greater positive response than the visual stimuli. Changing the proportions of the four volatiles in the blend significantly reduced positive orientation responses to the stimulus source. Visual cues of wheat foliage and olfactory cues of either chopped wheat odor or the ‘grass odor’ blend gave greater responses when combined than when presented separately.

In flowing air or wind, nearly all insects demonstrated a rapid positive response to odors of chopped wheat and the ‘grass odor’ blend, significantly greater than the response to the same stimuli in still air. However, positive responses to visual cues were not significantly greater in wind than in still air. When combined with the olfactory stimuli in flowing air, visual cues did not increase the incidence of response. Grasshoppers responding to grass odors in wind moved more rapidly and directly toward the source, and stopped less often and for shorter durations than insects responding to odor in still air or to visual cues.

We conclude from these studies that M. sanguinipes adults show orientation behavior to both visual and olfactory stimuli from food plant sources, although leaf odors elicit a stronger positive response particularly when carried by wind.
Differential predation by Coleomegilla maculata on Colorado potato beetle strains that vary in growth on tomato
Authors: Lu Wenhua , Kennedy George G. , Gould Fred
Published: March 2011

This study tests the hypothesis that the generalist predator Coleomegilla maculata DeGeer causes differential mortality of Colorado potato beetle, Leptinotarsa decemlineata (Say), larvae differing in their degree of genetic adaptation to tomato (Lycopersicon esculentum Mill.) as a host plant. Results of a series of laboratory experiments demonstrate that adult C. maculata can cause higher mortality to nonadapted than adapted Colorado potato beetle larvae. The extent of differential mortality caused by C. maculata depended on age of potato beetle larvae; presence of potato beetle eggs; whether or not the predator had a choice among prey items; and, in choice situations, the ratio of adapted to nonadapted potato beetle larvae. Although adult C. maculata have the potential to prey differentially on tomato‐adapted and nonadapted Colorado potato beetle larvae in mixed populations, the magnitude of differential predation in a natural setting could be highly variable.
Infestation rate of argan fruit (Argania spinosa) by the Mediterranean fruit fly (Ceratitis capitata) in relation to phenology and maturation of the fruit
Authors: Mazih Ahmed , Debouzie Domitien
Published: March 2011

Argan (Argania spinosa (Sapotaceae)) forest covers about 700,000 ha in the Souss region (Morocco). The medfly Ceratitis capitata Wiedemann (Diptera: Tephritidae) is known to develop in argans. In this study, we examine variations in medfly infestation rates according to argan phenology from 1987 to 1990. Argan phenology varies greatly among trees, total fruit drop spreading from late March to mid‐July; moreover, an exceptional fructification may occur in Autumn in some trees. From February to about May, the infestation rate is low except in fruit produced during autumnal fructification. In June and July, the rate increases greatly reaching 100% in some trees. Ripe and ripening argans are the most heavily infested; only 10% of immature fruits on the average are attacked by the medfly. Fallen argans are more heavily infested than fruit still on the tree. Productivity per argan averaged from one to three adult medflies. Our results demonstrate that argan forest in the Souss acts as an enormous reservoir of medflies for the nearby citrus orchards.

L'arganeraie (Argania spinosa) couvre environ 700000 ha dans la reégion du Souss, au Maroc. La mouche méditerranéenne des fruits, Ceratitis capitata, est connue pour se développer dans les arganes. Des études ont été menées, de 1987 à 1990, pour étudier comment le taux d'infestation des arganes variait selon leur degré de maturation. La phénologie des arganiers varie fortement selon les arbres: par exemple la chute totale des fruits s'étale de fin mars à mi‐juillet. De plus, une fructification peut être observée en automne mais elle ne concerne qu'un nombre limité d'arbres. De février à mai environ, le taux d'infestation des arganes reste faible, sauf pour les fruits produits pendant la fructification de l'automne précédent. En juin en juillet, le taux augmente fortement atteignant 100% dans certains arbres. Les arganes mûres ou mûrissantes sont les plus attaquées; seuls 10% en moyenne des fruits immatures sont infestés. Les fruits tombés sont toujours (sauf à la fin) nettement plus attaqués que ceux encore présents dans l'arganier. De une à trois Cératites adultes sont formées à partir d'une argane. Nos résultats démontrent que la forêt d'argane du Souss constitue un réservoir gigantesque de la Cératite pour les infestations des vergers d'agrumes proches.
Reciprocal influences and costs of parasitism on the development of Corcyra cephalonica and its endoparasitoid Venturia canescens
Authors: Harvey Jeffrey A. , Thompson David J. , Heyes Thomas J.
Published: March 2011

Many endoparasitoids develop successfully within a range of host instars. Parasitoid survival is highest when parasitism is initiated in earlier host instars, due to age‐related changes in internal (physiological) host defences. Most studies examining fitness‐related costs associated with differences in host instar have concentrated on the parasitoid, ignoring the effects of parasitism on the development of surviving hosts that have encapsulated parasitoid eggs. A laboratory experiment was undertaken examining fitness‐related costs associated with encapsulation of Venturia canescens (Hymenoptera: Ichneumonidae) eggs by fifth (L5) instar larvae of Corcyra cephalonica (Lepidoptera: Pyralidae). Growth and development of both host and parasitoid were monitored in C. cephalonica larvae containing 0, 1, 2, or 4 parasitoid eggs. Adult size and fecundity of C. cephalonica did not vary with the number of eggs per host. However, there was a distinct increase in host mortality with egg number, although most parasitoids emerged from hosts containing a single egg. The most dramatic effect on the host was a highly significant increase in development time from parasitism to adult eclosion, with hosts containing 4 parasitoid eggs taking over 2.5 days longer to complete development than unparasitized larvae. The egg‐to‐adult development time and size of adult V. canescens did not vary with egg number per host, as demonstrated in a previous experiment using a different host (Plodia interpunctella). The results described here show that there are fitness‐related costs to the host associated with resistance to parasitism.
Density of Anomoea flavokansiensis on Desmanthus illinoensis in monoculture and polyculture
Authors: Piper Jon K.
Published: March 2011

The effect of plant species diversity on the density of the herbivore, Anomoea flavokansiensis Moldenke (Coleoptera: Chrysomelidae), on Desmanthus illinoensis (Michaux) MacMillan (Mimosaceae), a promising North American legume for exploring the principles of diverse, perennial grain agriculture was examined. From mid‐June to early August A. flavokansiensis feeds on young leaves and inflorescences of D. llinoensis. At high density, A. flavokansiensis potentially reduces seed yield and is thus an important consideration for long‐term stands that are to be grown without insecticides. The potential to manage this insect via intercropping its host species with other, non‐host perennial species by monitoring A. flavokansiensis density on D. illinoensis within experimental monocultures, two‐species mixtures with Tripsacum dactyloides, and three‐species mixtures with T. dactyloides and Leymus racemosus was examined. Insects were censused 2–3 times weekly from mid‐June to early August at two sites from 1991 to 1995. In the first three years, beetle density was generally low (<1 per plant), and did not differ among treatments. In the fourth year, however, beetle density peaked at 15 and 25 insects per plant at the two sites, and was highest within monoculture for most dates. In 1995, density was again low, but tended to remain higher in monoculture at one site. The results suggest that beetle density on D. illinoensis can be reduced in polyculture and may hold promise for the management of this insect herbivore within perennial grain polycultures.
Host location by Gelis festinans, an eggsac parasitoid of the linyphiid spider Erigone atra
Authors: van Baarlen Peter , Topping Chris J. , Sunderland Keith D.
Published: March 2011

Interactions were investigated between the spider Erigone atra (Blackwall) (Araneae, Linyphiidae) and the insect parasitoid Gelis festinans (Fabricius) (Hymenoptera, Ichneumonidae), both found in an agricultural wheat field surrounded by grass edges. The searching behaviour of G. festinans was studied in laboratory experiments. Odours from detached wheat and grass leaves were preferred by male and female parasitoids when tested against clean air in Y‐tube olfactometer experiments. Female parasitoids, collected from the field, and their lab‐reared female offspring, preferred wheat odours when given the choice between wheat vs. grass odours. Male parasitoids showed no significant preference for wheat or grass leaves. Both field‐captured and lab‐reared female parasitoids responded to silk from the spider E. atra with an increased searching behaviour, while showing no response to silk from the spiders Lepthyphantes tenuis (Blackwall), Bathyphantes gracilis (Blackwall), Oedothorax retusus (Westring) and O. fuscus (Blackwall) (Araneae, Linyphiidae). Female parasitoids spent significantly less time on surfaces that were pre‐searched by themselves or conspecific females than on unsearched areas, even in the presence of E. atra webbing. Parasitized eggsacs were distinguished from unparasitized ones; superparasitization was not observed.
Effects of fenoxycarb on ovarian development, spring fecundity and longevity in winterform pear psylla
Authors: Horton David R. , Lewis Tamera M.
Published: March 2011

The insect growth regulator fenoxycarb prompts ovarian development in diapausing winterform pear psylla, Cacopsylla pyricola (Förster) (Homoptera: Psyllidae). We applied fenoxycarb to caged psylla in September, November, and December to test whether premature ovarian development reduced overwintering survival, spring fecundity, or spring longevity. Fenoxycarb prompted ovarian development in all treated psylla, with the largest effects occurring in the September‐treated insects. Recovery of live psylla in spring was 46–95% in treated insects and 72–92% in controls; overwintered insects from the fenoxycarb treatments survived field temperatures below −20°C despite having had mature ovaries. Fecundity and longevity of psylla were the same in treated and untreated insects, indicating that overwintering with mature ovaries did not cause reduced spring egglaying capacity. Several treated insects each deposited over 1900 eggs and survived more than 120 days. Due to their more advanced development, treated insects had higher oviposition rates than controls during the first 5 days after removal from the field. The largest impact on spring fitness was due to the effects of fenoxycarb on egg hatch. Eggs deposited on clean foliage by September‐treated females were less likely to hatch than eggs deposited by controls, suggesting that fenoxycarb affected developing eggs within the female. Prospects for using fenoxycarb in fall to control pear psylla appear to be limited.
Egg‐limited functional response of Uscana lariophaga, egg parasitoid of bruchid beetle pests in stored cowpea
Authors: van Alebeek Frans A. N. , Koning C. M. , de Korte E. A. P. , van Huis A.
Published: March 2011

The functional response of the egg parasitoid Uscana lariophaga Steffan (Hymenoptera: Trichogrammatidae) to eggs of its host Callosobruchus maculatus Fab. (Coleoptera: Bruchidae) was investigated in storage containers filled with a cowpea (Vigna unguiculata Walp.) seed mass. Foraging time was limited to 4 or 24 h. These indirect experiments were supplemented by direct observations of the parasitoid's handling time, egg‐laying capacity and initial egg load. The foraging process of U. lariophaga can be divided into two distinct stages: the process leading to detection of host clusters and, after arrival within a host cluster, the response of the parasitoid to the host density within the cluster. The chance that a cluster is found by U. lariophaga appeared independent of the number of host eggs per cluster, but was influenced by the available foraging time. Within a host cluster, U. lariophaga demonstrated a Holling II type functional response. Parasitoids were strongly arrested in host clusters, leading to high levels of parasitism. Direct observations proved that handling time was not a limiting factor, but that U. lariophaga's initial egg load and egg maturation rate limited the plateau level of her functional response. As such, direct observations were essential for a correct interpretation of the mechanisms underlying the shape of the functional response.
Preconceptional stress and racial disparities in preterm birth: an overview
Authors: KRAMER MICHAEL R. , HOGUE CAROL J. , DUNLOP ANNE L. , MENON RAMKUMAR
Published: March 2011

Objective. We reviewed the evidence for three theories of how preconceptional psychosocial stress could act as a contributing determinant of excess preterm birth risk among African American women: early life developmental plasticity and epigenetic programming of adult neuroendocrine systems; blunting, weathering, or dysfunction of neuroendocrine and immune function in response to chronic stress activation through the life course; individuals’ adoption of risky behaviors such as smoking as a response to stressful stimuli.Methods. Basic science, clinical, and epidemiologic studies indexed in MEDLINE and Web of Science databases on preconceptional psychosocial stress, preterm birth and race were reviewed.Results. Mixed evidence leans towards modest associations between preconceptional chronic stress and preterm birth (for example common odds ratios of 1.2–1.4), particularly in African American women, but it is unclear whether this association is causal or explains a substantial portion of the Black–White racial disparity in preterm birth. The stress‐preterm birth association may be mediated by hypothalamic‐pituitary‐adrenal axis dysfunction and susceptibility to bacterial vaginosis, although these mechanisms are incompletely understood. Evidence for the role of epigenetic or early life programming as a determinant of racial disparities in preterm birth risk is more circumstantial.Conclusions. Preconceptional stress, directly or in interaction with host genetic susceptibility or infection, remains an important hypothesized risk factor for understanding and reducing racial disparities in preterm birth. Future studies that integrate adequately sized epidemiologic samples with measures of stress, infection, and gene expression, will advance our knowledge and allow development of targeted interventions.
Aesthetics of implant‐supported single anterior maxillary crowns evaluated by objective indices and participants' perceptions
Authors: Vilhjálmsson Vilhjálmur H. , Klock Kristin S. , Størksen Kjell , Bårdsen Asgeir
Published: March 2011

Aim: The objective of this study was to evaluate the aesthetics of implant‐supported single crowns in the anterior maxilla using objective indices and patients' perception.

Methods: Fifty participants, former patients (mean age 31.3 years) at the Dental Hospital, University of Bergen, or at Haukeland University Hospital in Bergen, Norway, who had implant‐supported single crowns replacing upper anterior teeth lost due to trauma or agenesis during 2006, were included. One year after placement of the crown, an evaluation was carried out using the Pink Aesthetic Score (PES), the Implant Crown Aesthetics Index (ICAI), a modified version of the ICAI (mod‐ICAI), and the index of the Californian Dental Association (CDA). The participants rated their satisfaction with the crowns and adjacent soft tissue.

Results: The form of the crown was satisfactory for 88% and the colour for 84% of participants, while 72% were satisfied with the adjacent mucosa. A statistically significant bivariate correlation was found between the PES and the ICAI and mod‐ICAI. A weaker association was found between the CDA and the ICAI, mod‐ICAI and PES. A positive correlation was found between the mod‐ICAI index and satisfaction with the form and colour of the crowns and with the sum of ratings of responses to the questions about the form and colour of the crowns and the form and colour of the adjacent mucosa (P<0.05). Although most participants were satisfied, objective evaluation showed that a good aesthetic outcome for single implants was related to the quantity of the peri‐implant mucosa.

Conclusion: The mod‐ICAI index correlated with responses to questions about the form and colour of the mucosa. Other significant correlations were found between the participants' aesthetic perceptions and the ICAI and the mod‐ICAI. The mod‐ICAI combined best objective and subjective assessment of aesthetics related to implant‐supported crowns.

To cite this article:
 Vilhjálmsson VH, Klock KS, Størksen K, Bårdsen A. Aesthetics of implant‐supported single anterior maxillary crowns evaluated by objective indices and participants' perceptions. Clin. Oral Impl. Res. xx, 2011; 000–000. doi: 10.1111/j.1600‐0501.2010.02128.x