This review uses a data-driven, quantitative method to summarize the published, peer-reviewed literature about the impact of genetically modified (GM) plants on arthropod natural enemies in laboratory experiments. The method is similar to meta-analysis, and, in contrast to a simple author-vote counting method used by several earlier reviews, gives an objective, data-driven summary of existing knowledge about these effects. Significantly more non-neutral responses were observed than expected at random in 75% of the comparisons of natural enemy groups and response classes. These observations indicate that Cry toxins and proteinase inhibitors often have non-neutral effects on natural enemies. This synthesis identifies a continued bias toward studies on a few predator species, especially the green lacewing, Chrysoperla cornea Stephens, which may be more sensitive to GM insecticidal plants (16.8% of the quantified parameter responses were significantly negative) than predators in general (10.9% significantly negative effects without C. cornea). Parasitoids were more susceptible than predators to the effects of both Cry toxins and proteinase inhibitors, with fewer positive effects (18.0%, significant and nonsignificant positive effects combined) than negative ones (66.1%, significant and nonsignificant negative effects combined). GM plants can have a positive effect on natural enemies (4.8% of responses were significantly positive), although significant negative (21.2%) effects were more common. Although there are data on 48 natural enemy species, the database is still far from adequate to predict the effect of a Bt toxin or proteinase inhibitor on natural enemies.

Summer drought associated with high temperatures recorded in the last few years has given rise to outbreaks of bark beetles developing in weakened host trees. The aim of this study was to investigate the possible weather effect on the biology of and damage caused by Ips typographus L. in the southeastern Alps. The study was carried out recording temperature (1962–2007), precipitation (1922–2007), and the damage caused by I. typographus (1993–2007). In addition, data from pheromone-baited traps (1996–2005) provided information on the main periods of flight activity of I. typographus. From 1922 to 2007, precipitation during March-July has decreased ≈200 mm (-22%), whereas since 1962–2007, mean temperatures during March-July increased ≈2°C ( 13%). Damage caused by I. typographus was inversely correlated with March-July precipitation from the previous year but not correlated with temperature. Increases in spring temperature did not affect the development timing of the first generation, but only changed its onset. Earlier swarming of both over-wintering beetles and first-generation offspring (≈20 d sooner over 10 yr), and the early start of the second generation permitted more complete development of the second brood. Voltinism in this species is discussed in relation to thermal and photoperiodic thresholds, indicating that the occurrence of a third generation is limited by the summer photoperiod rather than by temperature. In conclusion, results suggest that spring drought increases damage caused by I. typographus in the following year, whereas warmer spring affects insect phenology.

This study analyzes the structure and composition of ant communities in citrus orchards in Catalonia (northeast Spain) and compares them with the ant fauna found in natural communities of the region. In the citrus orchards considered in this study, the most abundant species were Lasius niger and Pheidole pallidula, which are behaviorally dominant species. Two other dominant species, Linepithema humile and Tetramorium caespitum, were also abundant, although only in one orchard. Species richness and diversity in the studied orchards were low compared with natural communities: although in orchards, there were few species and low diversity values, in natural communities, the number of species was higher and diversity also increased. This reduction of species richness and diversity was not modified by edge effects: only light and local differences were found between the inner part of the orchards and the orchard margins, and differences among orchards were greater than differences between inner parts and edges. The activity peaks of the different ant species actively foraging on these citrus orchards were distributed throughout the whole activity period of ants. Overall, the composition of ant communities present in the citrus orchards of this study was extremely poor. This agrees with the fact that monocultures are ecosystems associated with an inevitable loss of biodiversity and abundance of insect populations.

Prescribed fire and livestock grazing are used for the management and restoration of native grasslands the world over; however, the effects of these management techniques on ant communities are unclear. We examined the response of ants to these disturbances in grasslands in northern California. Twenty-four 30 by 30 m plots were established across two sites that received one of four treatments: grazing, fire, grazing and fire, or no treatment. Ants were censused using 240 pitfall traps with one preburn and two postburn samples (14 d and 1 yr after burning). We analyzed ant abundance using broadly defined groups based on feeding habit and/or habitat use and detected no grazing effect but a significant fire effect that differed by group. Immediate postfire sampling showed an increase in cryptic species (particularly Brachymyrmex depilis). One year after the fire, no response was detected for cryptic species, but burned plots had greater abundance of seed harvesters. Analysis of vegetation showed burned plots had significantly greater forb cover, which might have provided greater food resources, and also lower biomass, which might have facilitated foraging. Understanding the effects of these management tools on ant abundance complements our understanding of their effect on vegetation and assists conservation practitioners effectively manage grassland ecosystems both in California and beyond.

Populations of the invasive Frankliniella occidentalis (Pergande) are serious pests of agricultural crops in the Aconcagua Valley of central Chile. An extensive survey was conducted of 55 plant species in 24 families to identify plant hosts of F. occidentalis and to determine its relative abundance on each host during each season. A more intensive study was conducted on selected plant species serving as reproductive hosts to determine the population dynamics of F. occidentalis and to evaluate the potential importance of Orius species and other natural enemies for controlling F. occidentalis. Adults of F. occidentalis were active during each season of the year inhabiting the flowers of 91% of the sampled plant species in 22 families, and 86% of these plant species in 19 families served as reproductive hosts. The number of host plant species used was greatest in the spring and least in the winter. All of the hosts except Medicago sativa L. were used only when flowering. Populations of F. occidentalis were significantly aggregated in M. sativa in the terminal buds over the leaves when the host was not flowering, and in the flowers, followed by the terminal buds, followed by the leaves when the host was flowering. Larvae were 1.3–2.3 times more abundant on dates when M. sativa was flowering. There were no identifiable patterns in plant hosts based on endemicity or plant family. Most of the plant species used by F. occidentalis were inferior quality hosts where populations either declined or were stable. Populations of F. occidentalis on low-quality hosts generally escaped predation by Orius species and competition by other species of thrips. Only 25% of the food hosts and 28% of the reproductive hosts for F. occidentalis in the extensive survey, respectively, were host plants for Orius. Parasitoids and other predators were not found to be important in suppressing thrips on any of the plant hosts. Populations of F. occidentalis increased on only a few hosts, including M. sativa and Sisymbrium officinale L. Scop. These apparently are major sources of F. occidentalis adults invading crops. We conclude that F. occidentalis is established in central Chile and that it has replaced and possibly displaced the native Frankliniella australis (Morgan) as the most common thrips species.

The transmission of insect-vectored pathogens is dependent on the population dynamics of the vector. Epidemiological models typically assume that birth and death rates of pathogen-free and inoculative vectors are equal, an assumption that is not true for all pathosystems. Here, a series of simple and general epidemiological models were used to explore how assumptions about birth and death rates of vectors based on their infectivity status influence disease incidence. With fixed death rate of pathogen-free vectors, increasing the death rate of inoculative vectors reduced vector density, the proportion of vectors that were inoculative, and the proportion of hosts infected. This effect was mediated by acquisition rate. Specifically, increasing the acquisition rate increased the proportion of vectors that were inoculative, thereby increasing the proportion of the vector population that experienced the increased death rate. With fixed birth rate of pathogen-free vectors, variation in birth rate of inoculative vectors had little influence on disease incidence provided that the birth rate of pathogen-free vectors was much greater than their death rate. However, when the birth rate of pathogen-free vectors was only slightly greater than their death rate, large increases in the birth rate of inoculative vectors increased total vector density and disease incidence. The results indicate that assumptions about birth and death rates of vectors based on infectivity status can have important effects on the vector population that in turn affects disease incidence.

Species of Ceratocystis Ellis and Halstead s.l. include important plant pathogens such as C. albifundus Morris, De Beer, and M. J. Wingfield that causes a serious wilt disease of non-native, plantation-grown Acacia mearnsii De Wild, trees in Africa. The aim of this study was to identify the insects associated with C. albifundus in South Africa and to consider the means by which the pathogen spreads. Insects were collected weekly for 77 wk in a native ecosystem using modified pitfall traps. Trapped insects were identified, and fungi were isolated using carrot baiting and by plating them onto malt extract agar. Fungi were identified using morphological characteristics and DNA sequence comparisons. Three different nitidulid (Coleoptera: Nitidulidae) beetles, Brachypeplus depressus Erichson, Carpophilus bisignatus Boheman, and Ca. hemipterus L, were collected, of which the most common were the Carpophilus spp. Two Ceratocystis spp., namely C. albifundus and C. oblonga R. N. Heath and Jolanda Roux, were isolated from all three insect species. Insect numbers and fungal isolates decreased significantly in the colder months of the year. Of the two Ceratocystis spp., C. oblonga was most abundant, occurring on 0.5% of the Carpophilus spp. C. albifundus was isolated from 1.1% of the Brachypeplus individuals and from 0.01% of the Carpophilus individuals. This study presents the first record of insects associated with C. albifundus and C. oblonga and provides an indication of environmental influences on fungal and insect populations, which could contribute to future disease management.

We examined the interaction between the tomato leafminer, Tuta absolute (Meyrick) (Lepidoptera: Gelechiidae), a key pest of tomato crops in South America, and its main solitary larval parasitoid, Pseudapanteles dignus (Muesebeck) (Hymenoptera: Braconidae). The pattern of parasitism of T. absolute, by the parasitoid was studied at three scales on tomato crops: plant, leaf, and leaflet. Host density, spatial distributions of both host and parasitoid, percentages of parasitism, variation in the probability and risk of parasitism in relation to host density, and the spatial density dependence were assessed in a horticultural region in Argentina. The spatial distribution of T. absoluta was clumped at all sites and scales, whereas that of P. dignus was much more variable, fitting to negative, positive binomial distributions and to Poisson series. Percentages of parasitism were as follows: site 1,17.06%; site 2,27.53%; site 3,26.47%; site 4,45.95%. Parasitoid aggregation in relation to host density was found at leaf and leaflet scales. However, the proportion of parasitized hosts was independent of host density. The variability of parasitism rates exhibited at the three spatial scales seems to result in partial refuges for the host, which might contribute to the persistence of the interaction between host and parasitoid. We discuss our field observations in relation to ecological theory and its potential application to the biological control of T. absoluta on tomato.

Stink bugs (Hemiptera: Pentatomidae) cause significant damage to many different crops and horticultural commodities in Virginia. However, little is known about the species diversity or impact of stink bug egg parasitoids in the state. A survey was conducted in 2005 and 2006 (May through September) in wheat (Triticum aestivum L.), soybean (Glycine max L.), and several vegetable crops by collecting natural egg masses of various stink bug species and by monitoring sentinel egg masses. A total of 570 Euschistus servus (Say) eggs in 26 egg masses, 11,197 Murgantia histrionica (Hahn) eggs in 939 egg masses, 15 Podisus maculiventris (Say) eggs in 2 egg masses, and 546 Acrosternum hilare (Say) eggs in 18 egg masses were field collected and returned to the laboratory, where emerging parasitoids were identified to species. In addition, 2,512 laboratory-reared E. servus eggs and 230 P. maculiventris eggs were placed as sentinels into crop fields and collected after 7 d, and parasitoid or stink bug emergence was recorded. Four species of hymenopteran parasitoids in the family Scelionidae were recovered from stink bug eggs: Telenomus podisi Ashmead, Trissolcus basalis Wollaston, Trissolcus edessae Fouts, and Trissolcus euschisti Ashmead. In addition, one parasitoid in the family Mymaridae (Hymenoptera) was recovered. Parasitism rates were highest in E. servus with 89.7 and 49.2% of egg masses and individual eggs parasitized, respectively. The predominant parasitoid species was T. podisi.

Icerya purchasi Maskell is a polyphagous scale pest of ornamentals and several other crops. It has two natural specialist enemies that maintain its populations at low levels: Rodolia cardinalis (Mulsant) and Cryptochaetum iceryae (Williston). I. purchasi was recently observed in blueberry crops (Vaccinium corymbosum L.) in Argentina. Seven blueberry fields located in different agricultural landscapes were sampled from July 2006 to September 2008. I. purchasi was present only in the citrus areas of Gobernador Castro, San Pedro, and Concordia. In the last locality, it was present in January 2007, and the abundance was very low. In Buenos Aires, I. purchasi was more abundant in Gobernador Castro where it was present throughout all study period. In San Pedro, it was only registered in August 2007 and March, April, and June 2008. In Gobernador Castro, where the abundance was highest, the dominant crop near blueberries is citrus. The low abundance in San Pedro and Concordia fields may be attributable to the replacement of citrus crops by nonhosts. In Concordia and San Pedro fields, no parasitized I. purchasi were found. In Gobernador Castro, the proportion of adults parasitized was 0.805 ± 0.286. When the risk of parasitism was analyzed for three density categories, there were no significant differences. R. cardinalis was present only in Gobernador Castro, and very few individuals were observed. The presence and abundance of I. purchasi in blueberry crops in Argentina seems to be linked to the structure of the landscape at the regional level, and the variable incidence of C. iceryae suggests major constraints to the scale's population growth.

A complex of Fusarium spp., including F. pseudograminearum, F. culmorum, F. avenaceum, F. equiseti, and F. acuminatum, was isolated from field-collected larval cadavers of wheat stem sawfly at two locations for 2 yr. The Fusarium spp. isolates caused mortality in both diapausing larvae in a topical bioassay and in developing larvae feeding in infected stems in a greenhouse experiment. Larval mortality was >90% in both experiments at the highest dose. The pattern of correlation between integument discoloration, hyphal growth, and larval mortality showed that the Fusarium spp. isolates actively infect larvae and kill them, rather than colonizing larval tissue as secondary postmortem invaders. The versatility of Fusarium spp. as plant and insect pathogens enables colonization that results in disease in wheat plants and subsequent mortality of the wheat stem sawfly larvae developing within the same tissue.

Insects that vector diseases of plants are of critical concern to agriculture, but relationships between the vectors and pathogens often are poorly understood. In this study, we present research on vector relationships between the striped cucumber beetle, Acalymma vittatum (F.) (Coleoptera: Chrysomelidae), and the pathogen that causes bacterial wilt of cucurbits, Erwinia tracheiphila (Smith) (Enterobacteriales: Enterobacteriaceae). We studied how the bacteria were retained in the gut of the beetle by developing a polymerase chain reaction (PCR)-based technique for extracting and identifying bacterial DNA in the frass. Bacterial DNA usually was present in the frass for 24 h after beetles had consumed inoculum but diminished quickly and was undetectable within 96 h. The amount of time that bacterial DNA could be detected in frass increased with the amount of inoculum and the length of time that beetles were exposed to inoculum and also varied with the strain of bacterium. Frass that tested positive for bacterial DNA also was infective to cucumber plants, confirming that DNA was indicative of viable bacteria and that frass could be a pathway for transmission of the pathogen. This research suggests that few cucumber beetles serve as long-term vectors of the pathogen and that aggregation of the beetle on host plants may be critical for initiating plant infections in spring.

Many insect herbivores can only use hosts during a specific phenological stage, i.e., a phenological window. Previous studies have primarily examined the effects of these windows on insect herbivores, but relatively little is known about the mechanisms controlling the phenological windows. In most gall insect systems, phenological windows have been attributed to the short duration of physiologically active plant tissues that induce gall formation (reactive plant tissue). In the fruit gall midge, Asphondylia aucubae Yukawa and Ohsaki, and the host plant (i.e., Aucuba japonica) system, the disappearance of reactive plant tissue closes the phenological window, but its presence does not define the opening of the window. The hard endocarp of the fruit covers most potential oviposition sites just before the midge emergence season, but decreases in proportional cover during the emergence season. We experimentally manipulated the timing of oviposition relative to fruit development. Midges that emerged earliest and attacked fruits during their earliest developmental stages were unable to oviposit because of intact, hard endocarps, whereas their counterparts that emerged later could oviposit more readily through cracks in the endocarp. We noted possible oviposition avoidance behavior and the necessity of more frequent (repeated) ovipositor insertions to intensively stimulate the decreased reactive tissues during the latter half of the emergence season. Overall, our results indicated that the fragmentation of the defensive, hard endocarp of the host plant defines the opening of the phenological window in this plant-herbivore system.

The nature of the interaction between the black pecan aphid, Melanocallis caryaefoliae (Davis) (Hemiptera: Aphididae), and the chlorosis it causes to foliage of its pecan [Carya illinoinensis (Wangenh.) K. Koch) ] host is poorly understood. Laboratory experiments were conducted on the settling behavior of the black pecan aphid, when provided chlorotic pecan leaf discs resulting from previous black pecan aphid feeding and nonchlorotic leaf discs, under a normal photoperiod and constant dark. Additionally, aphid development from the first instar to the adult stage was examined when nymphs were either allowed to feed on the same leaf disc or moved daily to a new, nondamaged, same age leaf disc. After 24 h, a significantly higher percentage of black pecan aphids settled on chlorotic than on nonchlorotic leaf discs, regardless of photoperiod. When starting from the first instar, nymphs that were prevented from inducing leaf chlorosis by moving daily to new, same-age leaf discs took ∼5 d longer to complete development, had a shorter body length, and had higher mortality than when aphids remained on the same leaf disc. These results show that black pecan aphid-induced leaf chlorosis plays an important role in the interaction of the black pecan aphid with its pecan host.

Gall wasps (Hymenoptera: Cynipidae) hijack the physiology of their host plant to produce galls that house wasps throughout their immature stages. The gall-maker-host plant interaction is highly evolved, and galls represent an extended phenotype of the gall wasp. We evaluated two-way interactions between stem galls produced by Dryocosmus kuriphilus Yasumatsu on Castanea spp. (Fagales: Fagaceae) and foliage directly attached to galls (gall leaves) using gall leaf excision experiments and herbivore bioassays. Early season gall leaf excision decreased the dry weight per chamber (nutritive index) and thickness of the protective schlerenchyma layer and increased the number of empty chambers and the occurrence and size of exterior fungal lesions. Leaf excision also caused a modestly significant (α = 0.1) increase in the incidence of feeding chamber fungi and herbivory by Curculio sayi Gyllenhal (Coleoptera: Curculionidae), and a modest decrease in parasitoids. This study shows that gall leaves are important for stem gall development, quality, and defenses, adding support for the nutrient and enemy hypotheses. We also evaluated the effects of stem galls on the suitability of gall leaves to Lymantria dispar L. (Lepidoptera: Lymantriidae) herbivory to assess the extent of gall defenses in important source leaves. Relative growth rate of L. dispar larvae was greater on gall leaves compared with normal leaves, indicating that, despite their importance, gall leaves may be more suitable to generalist insect herbivores, suggesting limitations to the extended phenotype of the gall wasp. Our results improve our knowledge of host- cynipid interactions, gall source-sink relations, and D. kuriphilus community interactions.

Adult male Megacyllene robiniae (Förster) (Coleoptera: Cerambycidae) that are paired with a female often are challenged by conspecific males that attempt to displace them. In staged laboratory bouts, challenging males used seven distinct tactics to displace defending males, including wedging their head between the defender and the female (termed wedging), straddling the mated pair and pulling the defender off (prying), pulling it with the mandibles, batting it with the antennae, or pushing, biting, or kicking the defender. Individual challengers attempted as many as six different tactics in a single bout, repeating certain tactics multiple times. They often attempted tactics that were not very effective. For example, prying was one of the most common attempted tactics but was rarely effective. However, few challengers attempted to push defenders off the female, even though that tactic often was effective. Challengers apparently were influenced by context in their choice of particular tactics. For example, males that approached the mated pair from the side were likely to use wedging, whereas those approaching head on were more likely to bat with the antennae. Choice of tactic apparently was not influenced by absolute size of challengers, nor was it strongly influenced by relative size of defenders. However, the effectiveness of tactics varied significantly with relative body size: larger challengers were most successful when prying or pushing, while smaller challengers were most successful when biting and kicking. By using different tactics, relatively small males were as adept as larger males at displacing rivals.

Edge effect tests have been used in a number of studies on obliquebanded leafroller, Choristoneura rosaceana (Harris), to test for evidence of mated female immigration into pheromonetreated orchards. This type of test compares obliquebanded leafroller presence or activity around the perimeter of an orchard against presence or activity in the interior. Higher numbers detected around the edges of an orchard would indicate higher levels of flight activity at the edge, a pattern that could be generated by high levels of immigration. Recent work has shown that the spatial distribution of recaptured obliquebanded leafroller adults released from a single location can be directionally biased, which could obscure the ability to detect an edge effect. To test this theory, data from an orchard study conducted in 1991 that found no significant edge effect was reanalyzed. When we accounted for the directional bias in the distribution of first-generation mated female moths, we found an edge effect with significantly more mated females captured in the edge traps than in the center or mid-interior traps. No edge effect was found when the directional bias was ignored. In addition, second-generation males and mated females both showed a significant edge effect that had not been detected in the original analysis, which had combined both first- and second-generation data.

Field experiments were conducted to evaluate the effects of cover cropping and intercropping on population densities of silverleaf whitefly, Bemisia argentifolli Bellow and Perring, and the incidence of squash silverleaf disorder (SSL) in zucchini, Cucurbita pepo L., in Oahu, HI. Two cover crops, buckwheat (BW), Fagopyrum esculentum Moench, and white clover (WC), Trifolium repens L., or sunn hemp (SH), Crotolaria juncea L., and an intercropped vegetable, okra, Abelmonchus esculentus L., were evaluated during the 2003, 2005, and 2006 growing seasons, respectively. Population densities of whiteflies and SSL severity varied during the three field experiments. In 2003, the severity of SSL and percentage of leaves displaying symptoms were significantly lower on zucchini plants in WC than BW plots throughout the crops' growth cycle. Additionally, the percentage of leaves per plant displaying SSL symptoms was significantly greater in bare-ground (BG) compared with the pooled BW and WC treatments on each inspection date. In 2005, zucchini intercropped with okra had lower numbers of adult whiteflies and resulted in significantly lower severity of SSL than pooled BW and WC treatments. During 2006, zucchini grown with SH had significantly lower numbers of all whitefly stages (i.e., egg, immature, and adult) and less SSL severity symptoms than BW. Despite these differences in whitefly numbers and SSL severity, marketable yields were not significantly lower in BW compared with WC or SH treatment plots during the study. The mechanisms underlying these results and the feasibility of using cover crops and intercrops to manage B. argentifolli and SSL are discussed.

Early-season soybean, Glycine max L. Merrill, was evaluated in Arkansas soybean fields as a trap crop for a complex of stink bug species that included Nezara viridula L., Acrosternum hilare (Say), and Euschistus servus (Say). Early-season soybean production systems (ESPSs) are composed of indeterminate soybean cultivars planted in April. In the first year of a 2-yr study, field-scale trap crops (≈0.5–1.0 ha) of maturity group (MG) III and IV soybean were planted adjacent to production fields of MG V soybean. Stink bugs were attracted first to the ESPS trap crops and were twice treated with insecticide, yet damaging populations developed later in the MG V soybean adjacent to the trap crops. General sampling and observations of low stink bug densities in commercial fields of soybean and corn across the study area suggested that stink bugs were widely distributed across the agricultural landscape. These observations and the subsequent discovery of additional ESPS fields outside the study area suggested that developing populations in the adjacent MG V soybean probably did not originate from the trap crops. However the source of the populations colonizing MG V soybean could not be determined, and we concluded that the scale of future experiments should be increased to better control stink bugs dispersing from other ESPSs outside the study area. In the second year of the study, the experiment was expanded in size to a farm- or community-scale project where entire fields of ESPSs (8–32 ha) were used as trap crops. Insecticide was applied to the trap-crop fields and other fields of ESPSs within a 0.8-km radius of targeted response fields, yet again there was no apparent effect on subsequent populations of stink bugs in the MG V response fields. With the recent expansion of ESPSs in Arkansas, it may be difficult to use ESPSs as a trap crop to lower stink bug populations across large enough areas to suppress populations in late-season soybean. Also, multiple soybean cultivars are generally planted across a 2- or 3-mo period in Arkansas, which results in staggered soybean development across the landscape and extends the time period that soybean is attractive to colonizing stink bugs. Trap crops of ESPSs are only attractive for oviposition for up to 4–5 wk and cannot protect full-season soybean production systems (FSSPSs) for such an extended time period. This shift in production systems may limit the use of ESPS trap crops for management of stink bugs unless highly coordinated efforts are made to synchronize soybean maturity and control stink bugs in ESPSs across large geographic areas.

Sympatric insect species that do not share sex pheromone components but have a common host and overlapping adult flight periods are potential targets for the development of a combined sex pheromone-based monitoring tool. A system using a single synthetic pheromone blend in a single lure to bait a single trap to monitor two pests simultaneously represents a novel approach. In this study, a combined pheromone-based monitoring system was developed for two lepidopterous defoliators of trembling aspen Populus tremuloides Michenaux in western Canada, Malacosoma disstria Hubner (Lepidoptera: Lasoicampidae) and Choristoneura conflictana (Walker) (Lepidoptera: Tortricidae). Efficacy and longevity of a lure containing both species' pheromones were tested. Immature stages of each species were sampled to evaluate the ability of pheromone traps baited with the combined lure to predict population density. The combined lure was as attractive to M. disstria and C. conflictana males as were traps baited with each species' pheromone alone. Lure age had no effect on attraction of male C. conflictana to the combined lure but had a negative effect on attraction of M. disstria. The number of male moths captured in traps baited with the combined lure was related to immature counts for both species. Pupal counts of M. disstria and larval counts of C. conflictana provided the best relationships with male captures. The combined lure does not attract M. disstria males in direct proportion to population density, because trap catch was comparatively low at high-density M. disstria sites.

The red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Curculionidae: Scolytinae), has caused extensive mortality of Pinus tabuliformis Carrière in north central China. The electrophysiological and behavioral activities of the four bark beetle pheromones, frontalin, exobrevicomin, trans-verbenol, and cis-verbenol, singly or in combination with host-produced kairomones, were tested on red turpentine beetles. Both sexes showed a consistent electrophysiological response to the four test compounds. In Y-tube olfactometer bioassays, walking red turpentine beetles selected the host compound ( )-3-carene over any of the test compounds, but significantly higher numbers chose each tested pheromone over a blank control. The four compounds, tested singly or in combination, were not attractive to red turpentine beetles in field trapping studies in 2006 and 2007 and also did not significantly increase trap catch when combined with ( )-3-carene. Frontalin, alone or in combination with exo-brevicomin and trans-verbenol, significantly reduced the attractiveness of ( )-3-carene in 2006 but not in 2007. The possible roles of the pheromones in host and mate finding and selection are discussed.

Development of Dinoderus minutus was studied under laboratory conditions at five constant temperatures (15, 18, 25, 28, and 30°C) to estimate developmental thresholds and thermal requirements of the egg, larva, pupa, and egg-to-adult stages. Adults began to burrow along the grain into bamboo pieces within 24 h after cutting and continued across the grain. Female beetle oviposited an average of 9.1 eggs in the ensuing 24 h, all in the metaxylem. The average period for development of eggs, larva, and pupa were 5.4, 43.8, and 4.6 d at 30°C, respectively. The development rate data were regressed through the x-axis to derive the thermal constants of 4.3, 6.8, and 4.5°C and thermal requirements of 113.6, 909.1, and 96.2 DD to predict D. minutus egg oviposition to hatch, larva-to-pupa development, and adult emergence from pupa, respectively. The thermal threshold for egg-to-adult development was 6.4°C, with total thermal requirements of 1,111.1 DD. Oviposition, emergence, and thermal requirements for development of the various stages of D. minutus may be used for postharvest pest management of bamboo.

We examined stress responses and survival in developmental stages of the invasive solitary bee Megachile apicalis Spinola during two nesting seasons in the Central Valley of California to consider whether abiotic stress tolerance of its offspring contributes to this species' successful colonization of the western United States. In 2001 and 2003, artificial nesting cavities were affixed to vertical plywood boards oriented to maximize nest cavity temperature and humidity differences: one side faced south (exposed to direct sun) and the other one faced north (shaded). After several weeks of nesting activity, we measured heat shock protein 70 (HSP70) concentrations in adults and offspring on 1 d in both years and offspring survival and mortality sources in 2003. In 2001, M. apicalis showed higher HSP70 concentrations in exposed nests than in shaded nests during all developmental stages, adults and their offspring. In 2003, overall survivorship was not significantly different between treatments because exposed nests experienced high offspring mortality caused by heat stress, whereas shaded nests suffered similarly high offspring mortality because of parasitoids. In both years of our study, females preferred shaded nests over exposed nests. M. apicalis successfully reproduces in grasslands of the Central Valley of California where offspring survive hot, dry nest sites and parasitoids in sufficient numbers to inoculate new grassland habitats, unpopulated by tolerance-limited native solitary bees, with incipient populations of this bee, M. apicalis.

A bioassay was conducted to determine the impact of methoprene, an insect growth regulator (IGR), on fecundity, larval survival, and size of progeny for Onthophagus taurus Schreber. Adult O. taurus dung beetles were offered methoprene-treated manure in three to five replications each at concentrations of 0.08, 0.45, and 4.5 ppm, respectively. An additional group of adult beetles was immersed in a methoprene-water solution and allowed to reproduce in containers with untreated manure. Data from all treatment groups were compared with untreated control groups. Methoprene did not seem to hinder brood production at 0.45 ppm. Survival of O. taurus was not affected by methoprene-treated manure at 0.08 ppm or when parent beetles were immersed in methoprene-water solution. However, progeny survival was significantly reduced on manure treated with methoprene at 4.5 ppm. Mean pronotal width of O. taurus progeny was significantly smaller in beetles fed methoprene-treated manure (4.5 ppm). The low dose of 0.08 ppm did not affect pronotal widths nor did topical application of methoprene to adults affect pronotal widths in resulting offspring. Although some adverse effects of methoprene were observed at higher concentrations, use of methoprene at concentrations of 0.08 ppm as part of a horn fly control program likely would not greatly affect populations of O. taurus, the most common paracoprid dung beetle in North Carolina.

In the house fly, Musca domestica L. (Diptera: Muscidae), sex is usually determined by a dominant factor, M, located on the Y chromosome. However, there are autosomal male (A^M) populations in which the M factor is located on one or more of the five autosomes (I-V), most commonly on the third chromosome. Herein we report the use of isogenic strains to determine the relative fitness of Y^M versus III^M males in three different experiments. First, cages were started with 50% Y^M and 50% III^M males, and the frequencies of Y^M and III^M males were evaluated across generations. Second, mating competition studies were preformed with these isogenic strains. Third, the relative emergence rates of III^M versus Y^M male pupae held at three temperatures for 3 d were examined. All three studies indicate that III^M males have a greater fitness than Y^M males. In the cage competition studies, >90% of the males were III^M after seven generations. III^M males were more likely to mate than Y^M males, and a higher percent of III^M males emerged after being held as pupae at 4, 16, or 28°C for 3 d. The implications of these studies to the distribution of III^M and Y^M males in field populations are discussed.

A condition called “cypress mortality” affects forest of Austrocedrus chilensis (D. Don) Pic. Ser et Bizarri in Argentina. Their classic groups of symptoms has been described as a slow process of defoliation that culminating in death of the tree; nevertheless, dying and recently dead trees with abundant foliage are frequently observed in which foliage changes to red. Cinara (Cupressobium) cupressi (Buckton) is considered the agent responsible for reddening this indigenous conifer in Chile. Therefore, the relationship between the presence of C. cupressi and the new aerial symptoms in A. chilensis from Argentina required evaluation. However, Cinara (Cupressobium) tujafilina (del Guercio) also has been reported from this host, and the differentiation of both species of Cinara is time consuming and requires a great expertise because they share many morphologic and microscopic characters. A rapid molecular method of identification of C. cupressi and C. tujafilina is desirable to detect and differentiate them. We report the development and evaluation of a polymerase chain reaction-restriction fragment length polymorphism method based on the mitochrondial cytochrome oxidase I gene to identify C. cupressi and C. tujafilina in colonies of aphids. The first detection of C. cupressi from A. chilensis in Argentina, is reported based on the new method.