Most species of the genus Eulecanium Cockerell (Hemiptera: Coccidae) are important economic pests for ornamental plants and fruit trees. Two morphologically similar species, Eulecanium giganteum Shinji and E. kuwanai Kanda, are distributed mainly in China and are quite difficult to identify because of the paucity of distinguishing characteristics, which can only be observed in slide-mounted young, adult females. Furthermore, we demonstrate here that the species occur in sympatry and on many of the same host plants. Mitochondrial cytochrome c oxidase I (COI) and the D2–D3 expansion segments of 28S rDNA were used for accurate identification of these two Eulecanium species from 19 different locations in China. The average K2P distances of COI sequences were 0.47% in E. kuwanai and 0.32% in E. giganteum, and the interspecific divergences varied from 7.23% to 8.34%. Neighbour-joining (NJ) trees of COI and 28S rDNA revealed two distinct non-overlapping clusters, respectively. Meanwhile, “best close match” analysis also showed that 100% of individuals were classified successfully using COI and 28 S sequences. Differentiating between E. giganteum and E. kuwanai is challenging when using ecological and morphological traits. In contrast, identification using DNA diagnostics appears to be very effective, especially when slide-mounted specimens are difficult to obtain.

Chemoreception is a key process for insects. Odorant messages diffuse through the air and are translated into physiological signals by chemosensory receptor neurons in sensilla that are mainly located on insect antennae. We sequenced the antenna transcriptome of Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae), which is a serious pest of stored grains throughout regions with warm climates, and performed transcriptome analysis on R. dominica antennae. We obtained 57 million 90-base pair-long reads that we assembled into 37 877 unigenes with a mean size of 1007 base pairs. Predicted protein sequences were matched with Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) (79.1%), Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae) (1.7%), Megachile rotundata (Fabricius) (Hymenoptera: Megachilidae) (1.3%), Acyrthosiphon pisum Harris (Hemiptera: Aphididae) (1.2%), and other (16.7%) homologues. In chemosensory gene families, we identified transcripts that encoded the following putative genes: 12 odorant-binding proteins (OBPs), four pheromone-binding proteins (PBPs), eight chemosensory proteins (CSPs), five sensory neuron membrane proteins (SNMPs), six odorant receptors, and eight ionotropic receptors. The diversity of the predicted OBPs, PBPs, and CSPs are also discussed. These findings will advance our understanding of olfaction process by this pest.

The occurrence, quantification, and distribution patterns of deformed wing virus (DWV) and sacbrood virus (SBV), (family Iflaviridae); black queen cell virus (BQCV), Israeli acute paralysis virus (IAPV), Kashmir bee virus (KBV), and acute bee paralysis virus (ABPV) (family Dicistroviridae), and chronic bee paralysis virus (CBPV) (unclassified), were characterised in 80 “healthy” honey bee (Apis mellifera Linnaeus; Hymenoptera: Apidae) colonies and 23 “unhealthy” colonies by employing reverse transcription polymerase chain reaction (RT-PCR) for virus identification and quantitative real-time polymerase chain reaction (qPCR) for quantification. All seven viruses were common but the most prevalent viruses were DWV, followed by BQCV and IAPV. For most viruses, prevalence in surviving but unhealthy colonies in spring did not differ from that of healthy baseline colony levels in fall suggesting spring prevalence level would not be a useful metric for diagnosis of factors contributing to colony loss. Sacbrood virus was the only virus that was more prevalent in unhealthy colonies from Manitoba, Canada than in healthy from colonies across Canada but did not differ from healthy colonies within Manitoba. Multiple infections were ubiquitous with a few colonies having simultaneous infection with as many as five viruses. Among the three viruses quantified by qPCR, DWV had the highest relative concentrations in pooled samples of worker bees. Deformed wing virus was the only virus within healthy colonies that differed in fall concentration among provinces and was at high levels in unhealthy colonies. Black queen cell virus was positively correlated with IAPV across all samples. Our study provides the first major baseline study of viruses in Canadian honey bees.

For quaking aspen (Populus tremuloides Michaux; Salicaceae) the rate of extrafloral (EF) sugar secretion is increased by defoliation and decreased by drought. Although wholesale blocking of EF nectar has been shown to reduce ant (Hymenoptera: Formicidae) visitation to aspen, the effect of more subtle and realistic variations in nectar availability on ant recruitment is unknown. Working in Alaskan boreal forest (United States of America), we reduced and supplemented EF nectar availability on potted aspen ramets of three genotypes and surveyed visitation by free-living Formica fusca (Linnaeus) (Hymenoptera: Formicidae). Ants were more responsive to a subtle increase in sugar availability than to a decrease. While nectar reduction had no effect on ant visitation, nectar supplementation increased ant visitation to one aspen genotype by 70% during an early summer trial. Average ant visitation to different aspen genotypes varied during the late summer, indicating that aspen genotype can influence attractiveness to ants. We conclude that natural induction of EF secretion in response to herbivory may benefit aspen through improved ant recruitment, though the response is dependent on aspen genotype and time of year. Differences among aspen genets in attractiveness to ants could influence the relative success of genotypes, especially in settings in which aspen regenerates from seed.

Seventeen Myodes gapperi (Vigors) (Rodentia: Cricetidae), 13 Peromyscus maniculatus (Wagner) (Rodentia: Cricetidae), 12 Microtus pennsylvanicus (Ord) (Rodentia: Cricetidae), four Zapus princeps Allen (Rodentia: Cricetidae), three Ictidomys tridecemlineatus (Mitchill) (Rodentia: Sciuridae), and eight shrews (Soricomorpha: Soricidae) collected at Blackstrap Lake (BL), and 48 P. maniculatus, 15 Z. princeps, 15 M. pennsylvanicus, and one Sorex monticolus Merriam (Soricomorpha: Soricidae) collected at Saskatchewan Landing Provincial Park (SLPP), in southern Saskatchewan, Canada were examined for ticks. Although no adult ticks were detected on small mammals at either locality, Dermacentor variabilis (Say) (Acari: Ixodidae) larvae (n=144) and nymphs (n=7) were found on four species of small mammal at BL. At SLPP, both D. variabilis larvae (n=71) and nymphs (n=6), and Dermacentor andersoni Stiles (Acari: Ixodidae) nymphs (n=9) were collected from small mammals. Both tick species were present on P. maniculatus and M. pennsylvanicus at SLPP, indicating an overlap in their host range and, hence, the potential for transmission of microorganisms between tick species at sites where they coexist. However, the results of polymerase chain reaction assays used to detect bacteria of the genus Rickettsia da Rocha-Lima (Rickettsiaceae) in ticks, revealed that R. peacockii Niebylski et al. only occurred in nymphs of D. andersoni, whereas no Rickettsia were present in the larvae and nymphs of D. variabilis.

Wheat midge, Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae), Palaearctic in origin, is thought to have been introduced into North America in the early 1800s. It is a major pest of spring wheat (Triticum aestivum Linnaeus (Poaceae)), durum wheat (T. durum Desfontaines), triticale (X-Triticosecale), and, to a lesser extent, spring rye (Secale cereale Linnaeus (Poaceae)) throughout the northern Great Plains. Climate is the principal factor regulating the distribution and abundance of most insects. A bioclimate simulation model was developed to explain the current distribution and abundance of S. mosellana. The current distribution for North America, Europe, and Asia was consistent with model projections. General circulation model scenarios (CSIRO-MK 3.0 and MIROC-H) for the 2030 and 2070 time periods were applied to the bioclimate simulation model of S. mosellana to assess the potential impact of changing climates on their distribution and relative abundance. Potential changes to relative abundance and distribution were most sensitive to time period, as opposed to climate change scenario. Differences between the MIROC-H and CSIRO-MK 3.0 models were restricted to particular regions in North America. The study found that the range and abundance of S. mosellana, and associated crop risk, was predicted to expand in a northerly direction and contract across the present southern limits.

A novel “rearing-tube” method was developed and used to investigate the performance of mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), with its three main ophiostomatalean fungal symbionts, Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer, and Wingfield (Ophiostomataceae), Ophiostoma montium (Rumbold) von Arx (Ophiostomataceae), and Leptographium longiclavatum Lee, Kim, and Breuil (Ophiostomataceae). Transparent glass tubes filled with sterile ground jack pine (Pinus banksiana Lambert; Pinaceae) phloem and sapwood (9:1 ratio) were used to rear MPB from egg to adult with each fungus under controlled environmental conditions. Mountain pine beetle mortality was higher and development longer in fungus-free controls compared to fungal treatments. Among fungal treatments, insects developed faster, constructed shorter larval galleries, and had fewer supernumerary instars with L. longiclavatum. Insect survival was not affected by fungal treatments. Hyphal extension through the rearing medium was fastest for L. longiclavatum. Phloem nitrogen was reduced significantly by the presence of L. longiclavatum. Results support the hypothesis that ophiostomatalean symbionts provide benefits to MPB. The rearing-tube method is useful to tease apart confounding interspecific interactions between bark beetles and symbiotic fungus species.

The walnut twig beetle (WTB), Pityophthorus juglandis Blackman (Coleoptera: Curculionidae), vectors a fungus, Geosmithia morbida Kolařík, Freeland, Utley, and Tisserat (Ascomycota: Hypocreales), which colonises and kills the phloem of walnut and butternut trees, Juglans Linnaeus (Juglandaceae). Over the past two decades, this condition, known as thousand cankers disease (TCD), has led to the widespread mortality of Juglans species in the United States of America. Recently the beetle and pathogen were discovered on several Juglans species in northern Italy. Little is known about the extra-generic extent of host acceptability and suitability for the WTB. We report the occurrence of both the WTB and G. morbida in three species of wingnut, Pterocarya fraxinifolia Spach, Pterocarya rhoifolia Siebold and Zuccarini, and Pterocarya stenoptera de Candolle (Juglandaceae) growing in the United States Department of Agriculture-Agricultural Research Service, National Clonal Germplasm Repository collection in northern California (NCGR) and in the Los Angeles County Arboretum and Botanic Garden in southern California, United States of America. In two instances (once in P. stenoptera and once in P. fraxinifolia) teneral (i.e., brood) adult WTB emerged and were collected more than four months after infested branch sections had been collected in the field. Koch’s postulates were satisfied with an isolate of G. morbida from P. stenoptera, confirming this fungus as the causal agent of TCD in this host. A survey of the 37 Pterocarya Kunth accessions at the NCGR revealed that 46% of the trees had WTB attacks and/or symptoms of G. morbida infection. The occurrence of other subcortical Coleoptera associated with Pterocarya and the first occurrence of the polyphagous shot hole borer, a species near Euwallacea fornicatus Eichhoff (Coleoptera: Curculionidae), in Juglans are also documented.

The tomato looper, Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae), is a major pest that feeds on some fodder crops, vegetables, and ornamental plants in diverse plant families. We studied the effect of different cultivars of tomato including: Cal.JN3, Hed Rio Grande, Rio Grande UG, SUN 6108 f1, Super crystal, and Super strain B on the life history of C. chalcites under laboratory conditions (25±1 °C, 65±5% relative humidity, and 16:8 (light:dark hours). Data were analysed using the age-stage, two-sex life table method. Tomato cultivars had significant effects on developmental time of larvae, pupae, and total preadult stages of C. chalcites. The longest (17.39 days) and the shortest (13.93 days) larval period were observed on Hed Rio Grande and SUN 6108 f1, respectively. The longest pupal period was observed on Cal.JN3 (12.16 days) and Hed Rio Grande (12.11 days) compared with other cultivars. The lowest amount of larval growth index and rate of ovipositon days was observed on Cal.JN3. The results of this study revealed that Cal.JN3 and Hed Rio Grande were the less suitable cultivars to C. chalcites compared with other cultivars studied and can be used in integrated pest management programme of this pest.

The effect of four varieties of Lathyrus sativus Linnaeus (Fabaceae) seeds (Bio L 212 Ratan, Nirmal B-1, WBK-14-7, and WBK-13-1) on the bionomics of Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) was studied under laboratory conditions. Total larval developmental time was longer on WBK-13-1 than Bio L 212 Ratan. Adult emergence was highest on Bio L 212 Ratan followed by Nirmal B-1, WBK-14-7, and WBK-13-1. The development and fecundity were related with nutrient and antinutritional factors of khesari seeds. Total carbohydrates and proteins were highest in Bio L 212 Ratan and Nirmal B-1 while lipids and nitrogen were highest in Bio L 212 Ratan and least in WBK-13-1. Amino acids were higher in Nirmal B-1 and WBK-13-1. Phenols were greatest in Nirmal B-1 and least in Bio L 212 Ratan and WBK-14-7. β-ODAP was higher in Bio L 212 Ratan and Nirmal B-1. The lower levels of carbohydrates, proteins, lipids, nitrogen, water content, and higher trypsin inhibitor activity of WBK-14-7 and WBK-13-1 may explain the higher developmental time and lower fecundity of C. maculatus on these varieties. These results suggest that infestations of C. maculatus may be easier to manage on WBK-14-7 and WBK-13-1 than on the other varieties of khesari seeds.

The effect of the insecticide endosulfan on the predatory efficiency of the green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) on the eggs of tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera: Noctuidae) and fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) was measured with Holling’s disc equation. Though the type II functional response was maintained in C. carnea exposed to endosulfan, the functional response parameters: attack rate (a′), handling time (Th), total handling time (Tht), searching time (Ts), and search efficiency (E) were affected for both prey offered. The predator took more time to identify, pursue, capture, consume, and digest the prey, and in general, the efficiency of the predator as a biological control agent was adversely affected.

Detection of the exotic hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), in the crown of eastern hemlock, Tsuga canadensis (Linnaeus) Carrière (Pinaceae), relies mainly on two techniques: (1) sampling of branches from the lower half of the crown using pole pruners; and, (2) visual examinations of accessible foliage from the ground. As a result, infestations starting elsewhere than the lower crown may be missed because the upper crown is out of reach for both techniques. We developed a novel technique called ball sampling, and evaluated its sensitivity at detecting a range of A. tsugae ovisac densities as estimated by pole pruning branch tips of T. canadensis. We launched racquet balls covered with VELCRO® patches of hooks through branches and examined them for the presence of wool produced by A. tsugae. Ball sampling was as effective as pole pruning at detecting infestations in individual trees. If A. tsugae abundance on branches was ⩾0.1 per 10 cm of twig length, as estimated by branch-tip sampling, ball sampling always detected wool in 10 or fewer samples. This technique has the potential to improve detectability of A. tsugae infestations because it can effectively access foliage that is typically inaccessible to other ground-based detection tools.