Pathogen spillover from managed to wild pollinators represents an emerging threat to global pollinator diversity. However, surveillance of microbial pathogens in tropical wild bee communities remains severely limited. We investigated Nosema ceranae detection prevalence in the orchid bee Euglossa imperialis across seasons at 2 ecologically contrasting sites in the Panama Canal corridor: a protected tropical forest and a semi-urban landscape. Using species-specific polymerase chain reaction (PCR) assays, we detected N. ceranae DNA in gut tissues of this euglossine bee. Detection prevalence was significantly higher at the protected forest site (34/44; 77.3%) than at the semi-urban site (12/38; 31.6%), with no seasonal effect observed. A literature synthesis revealed that Nosema parasites have been reported across at least 9 hymenopteran families, with N. ceranae showing the broadest distribution of reported associations among named species, including detections in managed and wild bees as well as social wasps. This study provides the first molecular detection of N. ceranae in E. imperialis and indicates that N. ceranae DNA is detectable in wild pollinator communities at 2 ecologically contrasting sites in the Panama Canal corridor. The higher detection prevalence at the forest site suggests that local spatial or ecological context may be an important correlate of exposure in this system, a hypothesis that will require testing with additional replicated sites and environmental covariates. These findings highlight the need for expanded pathogen monitoring in Neotropical pollinator communities and underscore the importance of integrating ecological surveillance with molecular diagnostics to assess emerging pathogen risks in tropical ecosystems.

Intensive agricultural production can reduce beneficial insects by limiting access to undisturbed habitat. Wildflower plantings are promoted as conservation strategies to support pollinators and natural enemies on farms, yet their effects on certain crop pests remain understudied. We evaluated whether wildflower plantings adjacent to highbush blueberry (Vaccinium corymbosum L.) fields increased natural enemy abundances and reduced Drosophila suzukii populations compared to fields without this practice. In 2019 and 2020, across 12 farms in Michigan representing 3 management types (conventional management without wildflower plantings, conventional with wildflower plantings, or no chemical pest management), we quantified natural enemies, monitored adult D. suzukii abundance and fruit infestation, and measured removal of D. suzukii pupae. Unsprayed fields supported the highest natural enemy abundance and pupal removal but also had the highest D. suzukii abundance. There was some limited evidence for wildflower plantings increasing natural enemies, such as post-harvest, but overall, there was no significant difference between conventionally managed sites with and without wildflower plantings, and no impact on D. suzukii pupal removal. Additionally, wildflower plantings increased D. suzukii adult abundances post-harvest and in the wildflower plantings compared to mown field margins. Fruit infestation generally remained low in conventionally managed fields irrespective of wildflower plantings. Together, these results suggest that wildflower plantings only provide limited benefits for natural enemies and do not aid in D. suzukii control. Though typically established for pollinators, understanding how habitat enhancements impact particular pests of concern is essential for designing strategies tailored to specific production systems.

Parasitoid hymenopterans are highly valuable pest control agents. Despite their necessity within the agriculture industry, they remain one of the most understudied groups of insects. Non-crop habitats adjacent to farmland provide critical ecological services for these beneficial insects and can act as a corridor from uncultivated land to fields; this interaction is a form of edge effect. Here, we evaluate how 3 types of non-crop field edges affected the diversity, richness, and abundance of parasitoid hymenopterans at varying edge distances in canola (Brassica napus L.; Brassicales: Brassicaceae). We also compiled all sampled genera into a survey of parasitoid Hymenoptera found in southern Alberta canola. We conclude: (1) non-crop boundaries have a weak effect on parasitoid communities within our study system; (2) variability in parasitoid diversity and composition was most pronounced among farms, suggesting a dominant role of farm management practices; (3) parasitoid diversity is highest at edge boundaries and decreases toward the field interior; (4) Diolcogaster spp. (Hymenoptera: Braconidae)-predominantly Diolcogaster claritibia Papp, first reported in Canada in 2014-was the dominant group of parasitoids in these fields, comprising 74% of collected specimens. Overall, the composition of parasitoid communities is likely more sensitive to individual farm management practices or landscape composition and configuration, rather than to the type of bordering non-crop habitat. Further research is needed to determine which of these farm-level drivers are influencing parasitoid communities.

Parasitoids depend on chemical cues to locate and parasitize their hosts, and flowering plants and essential oils may enhance this process within conservation biological control (CBC) strategies. This study aimed to evaluate the chemotactic responses of Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae) females and parasitism rates in the presence of components associated with a Brassica oleracea var. acephala (L.) cropping system: the flowering plant Lobularia maritima (L.) (sweet alyssum), the essential oil of Corymbia citriodora Hook (EOCC) (Myrtales: Myrtaceae), eggs of Plutella xylostella (L.) (Lepidoptera: Plutellidae), and the parasitoid T. pretiosum, tested either individually or in combination. In a double-choice olfactometer, sweet alyssum was attractive to T. pretiosum females, while cabbage exhibited a repellent effect. Host eggs and EOCC, when tested individually, did not attract the parasitoid. The combination of cabbage + eggs increased attractiveness, which was further enhanced by adding EOCC. Laboratory parasitism bioassays showed no differences among the treatments with cabbage, cabbage + EOCC, and cabbage + sweet alyssum, whereas the cabbage + sweet alyssum + EOCC treatment differed significantly. Under semi-field conditions, cabbage alone resulted in lower parasitism compared with the other treatments. Emergence rates were generally high (83% to 90%), except for cabbage + sweet alyssum + EOCC, which showed reduced emergence. Overall, sweet alyssum is highlighted as a valuable companion plant for attracting T. pretiosum, and EOCC showed potential to support the management of P. xylostella, although certain combinations may negatively affect parasitoid performance.

The codling moth, Cydia pomonella L., is a major oligophagous pest causing serious losses in apple and other rosaceous fruit crops. Although varietal differences in susceptibility to codling moth infestation have been reported, substantial damage may occur under inadequate management practices. The recent establishment of this pest in the apple-growing regions of Jammu and Kashmir, India, has highlighted the need for a better understanding of varietal preference and the influence of weather parameters on pest population dynamics. The present study was conducted during 2021 and 2022 in the karewas of Nadihal village, Baramulla district, to assess the varietal preference of codling moth based on fruit damage and infestation levels, and to determine the relationship between pest incidence and key meteorological factors. Ten apple varieties-Red Delicious, American Apirouge, Sur Saharanpuri, Hazratbali, Maharaji, Chamoora, Rail, Kisri, Titu, and Condition-were evaluated at different fruit developmental stages on both fallen and on-tree fruits. Red Delicious consistently recorded the highest fruit damage and infestation, whereas American Apirouge was the least susceptible. Infestation increased progressively with fruit development, with the lowest levels observed during May (fruit development stage I). Late-maturing varieties generally suffered higher damage intensity. Correlation analysis showed a positive association between codling moth infestation and maximum and minimum temperatures, while rainfall and relative humidity (morning and evening) were negatively associated with pest incidence. These findings support the use of varietal selection and weather-based monitoring for developing effective integrated pest management strategies against codling moth.

Forests in the western United States are experiencing increasing stresses from more frequent stand-replacing fires, insect outbreaks, and droughts. To mitigate these phenomena, forest managers are increasingly employing forest fuels management operations (tree thinning and prescribed fires) to reduce fire severities and inter-tree competition for water and soil nutrients. While such forest restoration programs have proven effective, the impacts on forest arthropod communities are largely unreported. In this 6-year case study, we examined the response of a surface-active (epigeic) beetle community (Coleoptera) in a mixed-conifer forest subjected to tree thinning followed by a prescribed broadcast slash burn. We used a Before-After/Control-Impact (BACI) design to test treatment effects on the beetle community composition, diversity, richness, evenness, individual species abundances, and trophic structure. We documented 289 taxa of Coleoptera and found that treatments caused significant changes in the beetle community's composition, with 21 common species increasing and 35 species declining in the more open post-treatment sub-canopy environment; only 3 common species were extirpated from the treatment sites, while 2 common species colonized the post-thinned/burned areas. Saproxylic species exhibited a decrease compared to controls after thinning and prescribed fire. Trophic structure species composition did not change, although numbers of individuals increased in the omnivore, fungivore, and detritivore trophic groups. Overall, our forest restoration treatments did not reach the level of impact from more severe forest disturbances (clear-cutting, or high-severity wildfires) and created a mosaic of grassy forest understory and small open meadow patches that would contribute to increased landscape arthropod diversity.

Edge-associated distributions of animals are common in natural and managed landscapes, where habitat contrasts influence species densities, behavior, and population dynamics. In agricultural systems, field edges often concentrate insect pests and their associated damage, yet whether edge aggregation enhances pest performance or creates density-dependent constraints remains unclear. We investigated this relationship in the North American tree fruit pest, plum curculio, Conotrachelus nenuphar (Coleoptera: Curculionidae), by quantifying pest spatial distribution, fruit injury, and reproductive performance in a 4.2-acre peach orchard containing 355 trees (Prunus persica var. "Fantasia"). Between 19 May and 25 August 2025, we measured adult abundance, feeding injury, oviposition scars, larval abundance and emergence, and larval mass across trees and then evaluated density-dependent effects on adult injury behavior using no-choice bioassays. Although adult abundance was evenly distributed throughout the orchard, feeding injury, oviposition scarring, and larval abundance were concentrated along orchard edges. Increased oviposition at edges produced greater larval abundance and density than in interior trees, demonstrating enhanced reproductive output. However, larvae from edge fruit were smaller on average, suggesting density-dependent constraints on offspring development. No-choice bioassays supported these patterns, with doubled adult densities increasing feeding injury by 38%. Edge-associated pest pressure was linked with reduced fruit yield, with damage increasing and yield declining from the orchard interior toward the edge. Together, these findings demonstrate that orchard edges promote pest reproductive output through spatial aggregation while density-dependent constraints emerge at high larval densities.

The elm borer, Saperda tridentata (Olivier, 1795) (Coleoptera: Cerambycidae), is a North American longhorn beetle that has been repeatedly intercepted in Europe on imported elm logs. Although climatic conditions are considered suitable for its establishment, uncertainty remains regarding the suitability of European tree species as hosts. We evaluated the potential host range of S. tridentata by testing 4 elm species (Ulmus glabra, Ulmus laevis, Ulmus minor, and Ulmus pumila), 3 maple species (Acer campestre, Acer platanoides, and Acer pseudoplatanus), and 3 poplar species (Populus alba, Populus nigra, and Populus tremula) that are widespread in Europe. No-choice and choice feeding bioassays were conducted to assess adult feeding preference, while no-choice development bioassays were performed to determine whether larvae could establish and develop within logs of the tested species. Adults fed on all elm species but showed no feeding activity on maples or poplars. Feeding levels on European elms did not differ significantly from those recorded on the primary North American host, U. americana. Larvae were recovered from logs of all 4 European elm species, confirming their suitability for larval establishment, whereas no larvae were found in maple or poplar logs. Adult emergence was limited, with only 3 individuals emerging from U. minor logs. Our results indicate that European elm species can support both adult feeding and larval development of S. tridentata, whereas the tested maple and poplar species appear to be unsuitable hosts. These findings suggest that host availability is unlikely to limit the establishment of S. tridentata in Europe if introductions occur.

Insects represent a major component of terrestrial biodiversity and ecosystem function, yet the environmental drivers of occurrence and detection remain poorly understood for many ground-dwelling taxa. Environmental gradients can influence both whether insect taxa occupy habitats and how frequently they are detected during sampling. Rhaphidophoridae (cave crickets) are moisture-dependent, ground-dwelling orthopterans associated with caves, rock crevices, and forest-floor refuges. Here, we used occupancy models that account for imperfect detection to examine how habitat structure and elevation influence detection and occupancy probabilities of Rhaphidophoridae across 75 sites, each measuring 1 hectare, in Hidalgo, Mexico. Rhaphidophoridae were present in 33 of 75 sites. The best supported model indicated that detection probability increased with forest-associated habitat structure (tree and shrub cover, deep leaf litter, refuge availability, and low disturbance), whereas occupancy probability increased with elevation. Herbaceous cover did not predict occupancy but was negatively associated with detection. These findings suggest that broad environmental gradients constrain occurrence, whereas detectability is associated with forest structure and lower human disturbance. Our study provides new ecological data on Rhaphidophoridae in Mexico and demonstrates how distinguishing between drivers of occupancy and detection can improve ecological inference from field surveys.

The foxglove aphid, Aulacorthum solani (Kaltenbach), is a major economic pest in Asian soybean fields. Previous studies on its life parameters often used detached soybean leaves, which may not accurately reflect development and reproduction due to disrupted nutrient flow. This study compared survival, development, and reproduction of A. solani on living versus detached leaves at 19, 22, 25, 28, 31, and 34 °C. Between 19 and 28 °C, aphids developed and reproduced successfully on both leaf types. At 31 °C, nymphs failed to mature on detached leaves but reached adulthood on living leaves, though no nymphs were produced. At 19, 22, and 25 °C, fecundity and net reproductive rate were overestimated on detached leaves. At 28 and 31 °C, adult longevity, total longevity, oviposition day, fecundity, intrinsic and finite rates of increase, and net reproductive rate were underestimated on detached leaves. The mean developmental rate (y, reciprocal of nymph duration) on living leaves in relation to temperature (x) follows the equation y = 0.0088 x-0.0717. The lower developmental threshold is 8.15 °C, and the effective cumulative temperature required for nymph-to-adult development is 113.64 degree-days. On detached leaves, the equation y = 0.0055 x + 0.0043 yields an invalid threshold of -0.78 °C and 181.82 degree-days. These findings underscore the necessity of using living soybean leaves for accurate life table studies of A. solani, critical for predicting field populations and improving control strategies.

Anoplophora glabripennis Motschulsky (Coleoptera: Cerambycidae) is an invasive wood-boring beetle that primarily infests Acer rubrum L. (Sapindales: Sapindaceae) in North America. The first signs of infestation in a host tree are oviposition pits indicating female beetles have attempted to place eggs in the phloem; however, the presence of oviposition pits does not always guarantee the presence and survival of eggs or larvae, and little is known about the relative success of beetle oviposition. To better understand A. glabripennis oviposition and early larval survival, we infested A. rubrum in a common garden environment. We conducted daily observations and destructively harvested these trees to analyze oviposition pit occupation, egg viability, and early larval survival, and compared patterns of oviposition success and survival with field-collected material from naturally infested host trees in the surrounding environment. Oviposition pits on field-collected material were also examined to explore potential links between host tree characteristics and A. glabripennis oviposition success. Our results support previous findings that fecundity is highly variable among individuals, that A. glabripennis oviposition pits were most commonly observed on host material with intermediate sized diameters (6 to 15 cm) and textured bark, and oviposition pits were often chewed without depositing an egg. Oviposition pit occupation, egg viability, and early larval survival were significantly lower on host trees in the common garden environment relative to naturally infested field material. Understanding oviposition and early survival and how host tree characteristics can impact fecundity can help improve detection and more efficiently utilize resources dedicated to invasive species management.

Drosophila suzukii (Matsumura), known as spotted-wing drosophila, is an invasive fruit fly that lays their eggs in soft-skinned fruits with its serrated ovipositor. In this study, we evaluated the effects of oviposition and residence behavior of D. suzukii by two saturated fatty acids (FAs): palmitic acid (C16:0) and stearic acid (C18:0). Both FAs were identified from a novel D. suzukii attractant, Decoy Attract and Kill, using gas chromatography-mass spectrometry and liquid chromatography-high resolution mass spectrometry. The FAs were then tested for their potential to alter oviposition in laboratory trials on blueberry with different concentrations and ratios to determine the optimal behavioral effects. We examined whether exposure to these FAs increased post-contact residence time and altered oviposition behavior. Exposure to 6.62 mg/L C16:0 and 3.61 mg/L C18:0 showed the strongest contact-mediated arrestment, resulting in increased oviposition on FA-treated blueberries. Females exposed to a 2:1 ratio of C16:0:C18:0 showed the greatest contact-dependent arrestment, followed by the 1:1 ratio, C16:0, and C18:0 alone. Additionally, we confirmed that both FAs act in a contact-dependent manner, increasing oviposition behavior after landing. Both C16:0 and C18:0 are effective contact-based arrestants that have the potential to protect soft-skinned fruits from D. suzukii oviposition damage.

Agricultural intensification and an associated reduction of in-field plant diversity have reduced the availability of essential resources needed by beneficial arthropods. Consequently, this has contributed to declines in insect abundance, diversity, and biological control services while shifting the balance in favor of insect pests. Field studies were conducted to investigate the influence of conservation tillage in concert with an interplanted living mulch and/or cover crop residue on arthropod natural enemy abundance and biological control services in sweet corn (Zea mays L.). Treatments included 1 conventional tillage treatment (1) and 3 no-till treatments with different cover crops (2 to 4): (2) cover crop residue, (3) living mulch + cover crop residue, and (4) living mulch + winter-killed residue. All cover crop diversified sweet corn contained a greater abundance of arthropods than conventional till (bare-ground). However, beneficial arthropod numbers varied according to arthropod community and sampling method. For illustration, a greater number of beneficial arthropods were detected on sticky cards in the living mulch + winter-killed residue treatment compared to the no-till with cover crop residue. Within the epigeal community, more beneficials were captured in pitfall traps within the living mulch + cover crop residue treatment compared to conventional till. Still, herbivore damage to sweet corn ears was similar among treatments each study year. Overall, the living mulch treatments tended to attract a greater abundance of beneficial insects, though this did not result in a reduction in ear-feeding damage by herbivorous pest insects.

Loss of floral resources and pesticide exposure are key drivers of wild pollinator declines. Synergistic interactions between pesticides and poor nutrition may exacerbate individual effects, but how these anthropogenic stressors interact remains poorly understood, particularly across understudied life phases. Queen bumblebees in temperate regions emerge from hibernation in spring and attempt to initiate a colony. In agricultural environments, queens typically emerge during (i) a carbohydrate "hunger gap," whereby nectar demand is higher than supply and (ii) during a time of year in which pesticide use is high. Here, we assessed the impact of carbohydrate limitation and exposure to the novel insecticide flupyradifurone on colony initiation of wild-caught bumblebee (Bombus terrestris) queens. Using a fully crossed experimental design, queens were exposed to a field-realistic concentration of flupyradifurone (1.6 ppm) at high (50% (w/w)) or low (15% (w/w)) sucrose concentrations. We found that bees provided with low-sucrose concentrations produced no eggs or larvae compared with 31.6% in the high concentration groups. Queens fed a lower concentration of sucrose also developed smaller ovaries and performed less nest initiation behaviors. We also found that exposure to flupyradifurone increased the activity of bumblebee queens, and that carbohydrate limitation and flupyradifurone synergistically reduced the likelihood of nest initiation behavior. These results demonstrate the importance of carbohydrate intake during the spring when queens are founding colonies, highlighting the need to consider not only floral diversity within environmental land management schemes but also floral quality.

DNA metabarcoding has become a relatively common tool for studying consumption of plants by arthropod herbivores and identifying pollen collected by pollinating insects. However, studies using molecular gut content analysis to detect pollen-feeding in generalist predators are exceedingly rare. Pollen-feeding is known to be important to the nutritional ecology of many generalist predators and is particularly well studied in phytoseiid mites. In apples, generalist phytoseiids such as Typhlodromus caudiglans Schuster (Mesostigmata: Phytoseiidae) and the stigmaeid predator, Zetzellia mali (Ewing) (Trombidiformes: Stigmaeidae), feed on both pest mites and pollen trapped on foliage. It is unknown whether these mites commonly pollen-feed or if they exhibit in-field preferences for pollen type. To detect likely pollen-feeding in these predatory mites, we sampled tree foliage and the ground cover (vacuum sampling) from an apple orchard for 9 weeks in 2019 and 2020, and plant DNA was detected through metabarcoded gut content analysis using the trnF and internal transcribed spacer 2 (ITS-2) regions. We detected DNA from 31 plant genera in our samples. Malus was the most common taxon, followed by Pinus, Brassica, Festuca, and Lactuca. Forty-six percent of phytoseiid and 34% of Z. mali samples were positive for non-Malus DNA. Changes in detection of several taxa (Pinus, Festuca, Hyoscyamus, Citrullus, Poa, and Solanum) throughout the monitoring period likely reflected temporal variation in pollen availability. Pollen availability may play a role in determining the composition of predatory mite communities. Metabarcoding to detect possible pollen-feeding has the potential to improve our understanding of the role of floral resources in conservation biological control.