The intromission of the male's long, flexible, threadlike phallus into the female's similarly long, thin, S-shaped vagina in tephritid flies is mechanically challenging. The male of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann, 1824), folds the basal portion of his phallus back on itself, inserts the folded portion into the female, and then gradually unfolds his phallus inside her vagina. The site of the fold in the phallus gradually moves distally, deeper into the female, dragging the distal portion of the phallus into her vagina. At the same time, the male pulls the tip of the female's ovipositor distally with his surstyli, straightening her vagina. The male uses his phallapodeme and asymmetrical syntergosternite to periodically clamp and release portions of his phallus that have not yet entered the female. Once the entire distal portion of the male's phallus is inside the female, he unfolds it and then moves its distal tip even deeper, reaching the inner end of her copulatory bursa. Straightening movements of the phallus due to increases in fluid pressure probably supply at least part of the force that drives the phallus into the female.

Despite the importance of native pollinators in agricultural systems, little is known about the potential competitive interactions among them or the way they exploit crops' floral resources. This study determines the temporal use of floral resources by, and interspecific interactions between, native bees and Apis mellifera L. (Hymenoptera: Apidae) in experimental plots of squash, Cucurbita moschata (Duchesne ex Lam.) Duchesne ex Poir. (Cucurbitaceae), and watermelon, Citrullus lanatus (Thunb.) (Cucurbitaceae). General and specific niche overlap analyses were done to determine whether temporally differential use of floral resources occurred. Direct displacement interactions at the floral level were quantified. The species with the greatest abundances were Peponapis limitaris Cockerell (Apidae), Partamona bilineata Say (Apidae), and A. mellifera. Overall, the niche overlap analyses in both crops suggested that floral resources are not used simultaneously by different bee species. Winner events during aggressive encounters suggested a hierarchy among bee species, with A. mellifera being one of the species with more winner encounters in both crops. It is suggested that those deciding whether or not to introduce A. mellifera into crops should consider whether the abundance of native bee species is sufficient to ensure efficient fruit production.

In the Mediterranean Basin, two species of true seed bugs in the genus Orsillus Dallas, O. maculatus Fieber and O. depressus Mulsant et Rey, share the exploitation of seed cones of Cupressaceae for feeding and reproduction and may carry spores of the pathogenic fungus Seiridium cardinale Sutton & Gibson, responsible for the cypress bark canker disease. We compared the life history of the two species. A total of 89 cone collections carried out in 10 Mediterranean countries confirmed that O. maculatus is most closely associated with Cupressus sempervirens L., although it may also infest some other Cupressus L. species and, more rarely, species of Chamaecyparis Spach. Orsillus depressus appears to be less host-specific, being capable of feeding and ovipositing on most of the native and exotic species of Juniperus L., Cupressus, and Chamaecyparis. On C. sempervirens, the abundance of each Orsillus species follows an inverted longitudinal gradient along the Mediterranean Basin, probably corresponding to the pathway of introduction of this tree species from its native eastern range towards western Europe. The dominance of O. maculatus progressively decreases from east to west, whereas O. depressus becomes dominant in the Iberian Peninsula. By contrast, O. depressus is the dominant seed bug on other Cupressaceae all over Europe and the Mediterranean Basin. In the area in which C. sempervirens has been introducted, both Orsillus species may live on the same tree, but morphological variability of both adults and nymphs often hinders accurate identification of the species. Based on frequency distribution, the relative length of the rostrum compared with that of the body seems to be a diagnostic character for specific identification of nymphs of the last two instars.

Pitch canker of pines (Pinus spp.) and Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) (Pinaceae) is caused by the fungus Fusarium circinatum Nirenberg et O'Donnell. In California, infections by F. circinatum occur largely through wounds caused by insects. Field experiments were initiated to determine whether the colonization activities of twig beetles, Pityophthorus spp. (Coleoptera: Scolytidae), could explain the incidence of pitch canker on Monterey pine (P. radiata D. Don), Bishop pine (P. muricata D. Don), ponderosa pine (P. ponderosa var. ponderosa Dougl.), knobcone pine (P. attenuata Lemm.), and Douglas-fir. Asymptomatic branches were cut from each of four pairs of tree species (Monterey–Bishop, Monterey–ponderosa, Monterey–knobcone, Monterey–Douglas-fir) at four sites and attached to the lower canopy of both heterospecific and conspecific host trees (total of four combinations per pair). After 10 weeks, branches were collected and placed in rearing tubes in the laboratory. Emerging insects were identified and placed on a Fusarium-selective medium. Monterey, Bishop, and ponderosa pines were more heavily infested by Pityophthorus spp. than Douglas-fir and knobcone pine. Furthermore, more Pityophthorus beetles emerged from Monterey pine branches placed in Monterey pine canopies than from Monterey pine branches placed in Bishop or ponderosa pine canopies, indicating that reduced emergence (colonization) was caused by the hetero specific host. Relatively fewer insects emerged from sites containing either Monterey and knobcone pines or Monterey pine and Douglas-fir. Fusarium circinatum was not isolated from emerging Pityophthorus spp. Susceptibility of the five host species, based on mean lesion lengths resulting from mechanical inoculations, varied significantly. The longest lesions were on Monterey pine and the shortest were on ponderosa pine and Douglas-fir. The low incidence of pitch canker on Douglas-fir and ponderosa pine in nature compared with that on Monterey, Bishop, and knobcone pines may be explained by the low colonization by twig beetles and the greater resistance of Douglas-fir and ponderosa pine to this disease, compared with the other three hosts.

Breeding experiments and rearing under variable controlled conditions have revealed that western and 2-year-cycle spruce budworms (Choristoneura occidentalis Freeman and C. biennis Freeman, respectively) from British Columbia, Canada, and their hybrid progeny have the inherent capacity for a variable number of diapause events and hence voltinism. While all crosses have at least one diapause, variability in the relative frequency of a second diapause is determined by genetic traits modified by the photoperiod and, to a lesser extent, temperature experienced during the larval stages. Second diapause appears fixed in C. biennis but is facultative and most frequent at short photophases (12L:12D) in C. occidentalis. Hybrids and backcrosses had responses intermediate to the parental responses under all environmental conditions. The occurrence of a facultative third diapause in all crosses underlines the inherent capacity for flexibility in voltinism in these species. These results are discussed in the context of past, present, and future distributions of alternative life cycles in closely related species.

Aleochara bipustulata (L., 1761) (Coleoptera: Staphylinidae) is a Palearctic species and a natural enemy of the cabbage root maggot, Delia radicum (L., 1758) (Diptera: Anthomyiidae). It has been identified as a candidate for introduction to Canada for classical biological control of D. radicum. Recent taxonomic studies assert that A. bipustulata is absent from the Nearctic; however, there are numerous publications reporting the presence of the species in North America. We examined voucher material relating to these publications and additional museum specimens labeled as A. bipustulata. In addition, we reared Aleochara spp. from D. radicum puparia collected in the Canadian prairie provinces. Specimens that, based on external anatomy, could be A. bipustulata were definitively identified using characters of the genitalia. All of the 141 museum specimens labeled A. bipustulata were found to be Aleochara verna Say, 1836. A total of 811 individuals of Aleochara spp. were reared from D. radicum puparia; of these, 690 were Aleochara bilineata Gyllenhal, 1810, 121 were A. verna, and none were A. bipustulata. We have found no evidence that A. bipustulata occurs in North America.

The spectral reflectance of phytophagous insects' host plants is usually quantified between 300–350 nm (ultraviolet, UV) and 700 nm (farred to infrared), and the shape and magnitude of the distribution of reflected light determine the hue, saturation, and intensity perceived by insects (Moericke 1969). Host perception also depends on the distribution of environmental light (Endler 1993) and on the constraints of the insects' visual system, which is usually described as dichromatic, with one type of photoreceptor responding maximally to blue light (λmax = ca. 400–470 nm) and another to green light (λmax = ca. 500–530 nm). UV receptors also appear to be common, if not ubiquitous (Briscoe and Chittka 2001; Mazza et al. 2002). Several phytophagous insects have been shown to use visual cues, including UV reflectance, to locate and (or) discriminate among plants (Prokopy and Owens 1983).

A 2-year study conducted in 0.6-ha apple (Malus domestica Borkh.) blocks examined the effects of treatment with pheromone rope dispensers on captures of the obliquebanded leafroller, Choristoneura rosaceana (Harris, 1841), and the redbanded leafroller, Argyrotaenia velutinana (Walker, 1863), in traps baited with varying dosages of pheromone lures or Isomate®-OBLR/PLR Plus pheromone rope dispensers. In untreated blocks, captures of male A. velutinana were high and did not differ among (i) traps baited with a standard lure loading used to monitor this pest, (ii) lure loadings 10 and 100 times the standard loading, and (iii) traps baited with an Isomate-OBLR/PLR Plus pheromone rope dispenser. In pheromone-treated blocks, captures of A. velutinana in traps were reduced 94%–99% for all loadings tested (up to 1000 times the standard loading). The results for C. rosaceana were different. In untreated blocks in 2002, traps baited with 10 or 30 standard lures captured significantly more C. rosaceana than traps baited with a single standard lure; however, in 2003, traps baited with the standard lure loading captured significantly more moths than traps baited with 100 and 1000 times the standard loading. Also, traps baited with Isomate-OBLR/PLR Plus pheromone rope dispensers captured significantly fewer C. rosaceana than traps with standard lures in untreated blocks. In pheromone-treated blocks, traps baited with standard monitoring lures and lures with higher loadings (10 and 1000 times the standard) captured equivalent numbers of C. rosaceana; the capture of moths was reduced by only 50%–71%. We conclude that Isomate-OBLR/PLR Plus pheromone rope dispensers deployed in Michigan, United States of America, are effective in disrupting orientation of A. velutinana; however, they are not very effective for C. rosaceana. In addition, increasing lure loading above that of 1× monitoring lures (rubber septa or membrane type) does not appear to reliably increase the effectiveness of monitoring of males of either leafroller species in orchards where pheromone ropes are deployed at recommended densities.

The western tussock moth, Orgyia vetusta Boisduval (Lepidoptera: Lymantriidae), formerly known as Hemerocampa vetusta (Boisduval), occurs primarily in coastal areas of central California and south into Mexico, with occasional records east of the central Sacramento and San Joaquin valleys (Ferguson 1978). Two biotypes, feeding on perennial yellow bush lupine, Lupinus arboreus Sims (Fabaceae), or silver dune lupine, Lupinus chamissonis Eschsch. (this study), and on California live oak, Quercus agrifolia Née (Fagaceae), respectively, have been recognized and were originally considered two separate species (Edwards 1881; Ferguson 1978). Various fruit and nut trees have also been reported as host plants (Atkins 1958)

Plant bugs, species of the genus Lygus Kelton (Hemiptera: Miridae), damage many crops in western Canada (Kelton 1980; Wise and Lamb 1998; Wise et al. 2000). Lygus lineolaris (Palisot de Beauvois), L. borealis (Kelton), and L. elisus Van Duzee are the most common species in the eastern prairie of Canada (Schwartz and Foottit 1992). Manitoba is the leading producer of buckwheat, Fagopyrum esculentum Moench (Polygonaceae), in North America, growing about 15 000 ha annually (Canada Grains Council 1999). Plant bug adults are known to oviposit (Painter 1927) and feed on buckwheat (Bugg and Ellis 1990), but little is known about their ability to develop on this crop. The objectives of the study were to determine (i) the species of plant bugs on buckwheat, (ii) their ability to develop on buckwheat, and (iii) the distribution of plant bugs within commercial fields of buckwheat in Manitoba.

Odonates are obligate predators (Pritchard 1964), and the composition of their diet is reflective of their microhabitat and effectiveness in detecting and capturing prey (Griffiths 1973; Thompson 1978). In an intermittent woodland pond in southern Ontario, Canada, three species of Sympetrum (Odonata: Libellulidae) were found to coexist: S. internum Montgomery, S. costiferum (Hagen), and S. obtrusum (Hagen). Sympetrum species spend most of their life cycle in the aquatic stage and consume prey at all nymphal stadia (Pritchard 1964; Corbet 1999). They overwinter in the egg stage, hatch in early spring, and typically emerge in late June to late July (Walker and Corbet 1975). To better understand the role of coexisting Sympetrum nymphs in this intermittent pond environment, and to evaluate potential mechanisms behind their coexistence, we collected seasonal abundance and body size data for 2 years and analyzed gut contents of each species. In addition, we experimentally tested the prey selection and predatory rate of two different size classes of Sympetrum nymphs and two of their potential competitors, Lestes sp. (Odonata: Lestidae) and Acilius sp. (Coleoptera: Dytiscidae), in laboratory microcosms.

The pink stem borer (PSB) (Sesamia nonagrioides Lefèbvre, 1827; Lepidoptera: Noctuidae) is the main insect pest of maize (Zea mays L., Poaceae) in the Mediterranean area. Maize varieties partially resistant to PSB have been identified, but few studies have documented the mechanisms of resistance involved. The objectives of this research were to study the levels of leaf and sheath antibiosis of a maize population, EPS12, and determine whether antibiosis improved over the selection process for less stalk tunneling. A hybrid check and two Bacillus thuringiensis (Bt) hybrids were also examined. Several bioassays were carried out in a control chamber to evaluate antibiosis of maize leaves and sheaths against PSB larvae. Leaf antibiosis was significantly higher for EPS12 than for the hybrid check and sheath antibiosis was low for all non-Bt hybrids studied. We conclude that leaf and sheath antibiosis was not significantly improved during the selection process. Future efforts should look for other possible mechanisms of resistance, such as stem rind antibiosis.

In Ontario apple orchards, the amount of synthetic codling moth (Cydia pomonella (L., 1758)) sex pheromone, E,E-8,10-dodecadien-1-ol (0.01–10.0 mg) used to bait traps significantly affected the mean total numbers of moths captured, whereas similar mean total numbers of moths were captured in traps baited with different amounts of pear-derived kairomone, ethyl (2E,4Z)-2,4-decadienoate (0.01–10.0 mg). The attractiveness of kairomone-baited traps was not increased by using greater amounts (100 and 1000 mg) of this compound. The attractiveness of the pheromone was not enhanced by the addition of kairomone. Similar patterns of adult male seasonal activity were observed when using pheromone-baited traps and kairomone-baited traps. The potential usefulness of kairomone-baited traps in the integrated management of C. pomonella in Ontario apple orchards is discussed.

Batrachedra Herrich-Schäffer, 1853 (Lepidoptera: Batrachedridae) is a widespread genus with species concentrated in tropical areas. This genus of about 140 described species has been put in several lepidopteran families, most recently in the Batrachedridae (Hodges 1999; Koster 2002). Batrachedra has 25 Nearctic species (Hodges 1983; Koster 2002), 17 Neotropical species (Becker 1984), 6 Palearctic species (Koster 2002), and 29 Australian species (Edwards 1996). Additional species occur in other areas such as Indonesia (Baringbing 1986). Here I report that the Palearctic species Batrachedra pinicolella (Zeller, 1839) is established in Connecticut, United States of America. Until now the range of the species was restricted to European countries and the far eastern Palearctic region (Riedl 1969, 1996; Bolov and Sinev 1990). The disjunct Asian populations may represent accidental introductions.

Caged assays and field tests were used to evaluate the effectiveness of organophosphorus, pyrethroid, neonicotinoid, and biologically derived insecticides for reducing populations of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham), a new pest of canola in Canada. Complete mortality of caged weevils occurred 48 h after treatment with disulfoton, deltamethrin, carbofuran, oxydemeton-methyl, and chlorpyrifos. Under field conditions, using plots or large strips in commercial fields from 1998 to 2001, only deltamethrin and cyhalothrin-lambda (both pyrethroids) consistently reduced weevil densities, even at high population levels. Chlorpyrifos also significantly reduced weevil numbers and damage in some years, but results were variable and efficacy was too low to manage weevils under outbreak densities. Other insecticides such as spinosad provided moderate weevil control and may have a role in weevil management depending on their effect on beneficial insects relative to more efficacious insecticides. Treatment of canola seed with imidacloprid, lindane, or acetamiprid did not reduce weevil damage. Further research is needed to establish economic thresholds for C. obstrictus in canola, to assess the effect of insecticides on nontarget natural enemies of canola insect pests, and to assess the potential for integration of chemical agents with biological and cultural control strategies.

The wheat stem sawfly, Cephus cinctus Norton, is the most important insect pest of dryland wheat, reducing both harvest efficiency and head weight. When wheat lodged (flattened) by C. cinctus is straight-cut, harvest efficiency is affected in three ways: (1) lodged stems are difficult to collect with the combine, so mature wheat is lost; (2) the combine has to operate more slowly to collect as many of the lodged stems as possible; and (3) there is increased risk of damage to the combine due to lowering of the combine header to recover lodged stems. An alternative harvest method is to swath the wheat before lodging occurs and place it in windrows prior to combining. When swathing is used, harvest efficiency is not affected by the C. cinctus infestation level; however, this type of harvesting is more expensive and labor-intensive than straight- cutting. Thus, swathing should be used only when the crop is heavily infested by C. cinctus, while straight-cutting should be used when the level of C. cinctus infestation is lower. Adapting harvesting practices to the C. cinctus infestation level requires a sampling plan that can reliably and cost-effectively predict the infestation level in a given field. In this study, we (i) evaluate the relationship between sampling effort along field edges and precision of the estimated average infestation level in 6 wheat fields, and (ii) generate a Gaussian regression analysis of the infestation level up to 200 m into 18 wheat fields using two variables, distance from the edge and average infestation level at the edge, as explanatory variables. We conclude that little additional precision for estimates of infestation level is gained by collecting more than 10 samples along field edges. We also conclude that the average C. cinctus infestation level along field edges can be used successfully to predict infestation levels up to 200 m into winter wheat fields. The proposed sampling should be implemented about one month before harvest to provide growers with enough time to make logistical preparations for harvest.

The habitat of Bolitotherus cornutus Panzer consists primarily of sporophores of the shelf fungus Fomes fomentarius (L.:Fr.) J. Kickx fil. Each sporophore is discrete and often several are present on a single dead log or standing snag, especially of paper birch (Betula papyrifera Marsh.). An exploratory approach was used to examine habitat use at three scales (the single sporophore, a single log supporting up to several sporophores, and a group of logs supporting sporophores) by modeling incidence of adult B. cornutus. Sporophore volume and decay were important for the beetles at all scales. Patches containing a variety of states of sporophores from alive to dead and decomposing are probably most suitable to B. cornutus. Results are compared with those for the related European beetle Bolitophagus reticulatus (L.), which is similar ecologically and also occupies F. fomentarius sporophores.

The use of the timing of moth catch in traps to predict the start of egg hatch by first-generation codling moth, Cydia pomonella (L.), in apple, Malus domestica Borkh. (Rosaceae), was evaluated with ethyl (E,Z)-2,4-decadienoate (pear ester) and (E,E)-8,10-dodecadien-1-ol (codlemone) lures. Two sets of paired traps baited with either lure were placed in each of seven orchards and checked daily during the spring flight in 2000 and 2001. Rearing of field-collected eggs and sampling of fruit for injury were used to estimate the date of first egg hatch. Moth catch in traps baited with codlemone and pear ester occurred approximately 144 and 105 degree-days prior to the start of egg hatch, respectively. The effectiveness of using the timing of sustained moth catch in traps baited with these lures as a biological reference point (Biofix) to predict the start of egg hatch when traps were checked every 3–4 d was evaluated in 11 orchards from 2000 to 2002. The calendar date for the start of sustained moth catch in traps baited with either lure varied widely among orchards and years. Significant differences in mean cumulative degree-days from first sustained moth catch until egg hatch were found among male moth catch in codlemone-baited traps and total and female moth catch in pear ester-baited traps. Adjusting the Biofix based on daily temperature thresholds significantly changed the cumulative degree-days required until egg hatch only for female moth catch. No significant differences were found in the accuracy of predicting the date of egg hatch using either the codlemone or pear ester lure or by adjusting the Biofix date using daily temperature thresholds. The cumulative degree-day totals required from Biofix until egg hatch had the lowest variability when the Biofix was (i) based on the sustained catch of female moths in a pear ester-baited trap and (ii) adjusted with a temperature threshold for moth activity.

Blaesoxipha atlanis (Aldrich) is a common parasite of Melanoplus sanguinipes (Fabr.) in western Canada. We tested the hypothesis that parasitism by B. atlanis reduces food consumption by adult M. sanguinipes. Unparasitized grasshoppers serving as controls and grasshoppers infected with a single parasite larva were fed known quantities of freshly cut wheat (Triticum aestivum L. ‘Katepwa’) (Poaceae) leaves in the laboratory. The median development time in hosts of larvae of both male and female B. atlanis was 5.5 days. Two thirds of parasitized grasshoppers died within 9 days of infection, but all control insects survived. The dry mass of leaves consumed each day did not differ between parasitized insects that died and insects that survived parasitism; both groups fed less than unparasitized controls. The influence of parasitism on food consumption differed between host sexes, with feeding being depressed earlier and more severely in female than in male grasshoppers. The reduction in food consumption was most pronounced on day 6 after infection, when parasitized males and females consumed only 10% and 7%, respectively, of the food consumed by unparasitized controls. Parasite sex did not influence food consumption. Grasshoppers that survived parasitism by B. atlanis resumed feeding, consuming as much as unparasitized counterparts. Reduced food consumption limited the ability of grasshoppers to compensate for the nutritional demands of developing parasite larvae. As a consequence, parasitized grasshoppers lost body mass during the interaction. We propose that the temporary reduction in feeding by grasshoppers parasitized by B. atlanis that survive parasitism is not evidence of host regulation, but is consistent with a stress-induced alteration in host behaviour.

The restructuring of the design of an existing trap such as the Pherocon® IC (Trécé Inc., Adair, Oklahoma) can be fraught with the dangers of changing a de facto standard in research. However, what we present here is not a restructuring but a simplification and acceleration of the process for changing the traps' liners (sticky bottoms). The assembly of components for the standard Pherocon IC traps is basically straightforward; however, it is time-consuming and may be messy and cumbersome when attaching or replacing trap liners. For a number of years, we have assembled IC traps without the provided tube spacer; instead, we have bent the suspension/assembly wire into a shape that gives the same consistent spacing between the trap top and liner but allows faster (Table 1) and cleaner replacement of the liner. Our method allows us to assemble the traps in the laboratory without the liner and perform final assembly in the field, where the traps are marked and baited and liners are added quickly; subsequent liner replacements are clean and fast.