Eriosoma lanigerum has become an increasing threat to apple orchards, partly due to the withdrawal of some insecticides such as neonicotinoids and organophosphates. Native to North America, this aphid completes its life cycle on apple trees, infesting roots, trunks, and branches, and causing yield losses. Among its natural enemies, the specialist parasitoid Aphelinus mali plays a key role in biological control and represents a successful case of classical biological control. However, data on the seasonal abundance of E. lanigerum and A. mali, and in particular on their interactions under temperate European conditions and different management systems, remain limited. Therefore, 3-year surveys were carried out in 5 apple orchards in northwestern Italy to assess the population dynamics of E. lanigerum and its regulation by A. mali under temperate climatic conditions. Aphid infestations increased in spring, peaked during summer, and declined toward autumn but varied considerably across years, orchards, and management systems. Infestation pressure was generally higher in organic orchards than in IPM orchards, reflecting differences in pesticide use. The abundance of A. mali broadly mirrored aphid dynamics, and parasitism rates generally increased after pest peaks, although timing differed among orchards. Analyses indicated that A. mali responds strongly to rising host density until a certain infestation threshold is reached, after which its control effect is expressed mainly through increased parasitism rather than higher adult abundance. These findings emphasize the density-dependent regulation exerted by A. mali and provide a quantitative basis for integrating parasitoid activity into decision thresholds for sustainable apple management.

Brown marmorated stink bug (BMSB), Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), severely impacts global hazelnut production, especially in Türkiye, the top producer, and Oregon, USA. This study analyzed seasonal BMSB population dynamics and damage types on hazelnut fruiting bodies across phenological stages. Field monitoring in Oregon's Willamette Valley (2014-2016) and Türkiye's Eastern Black Sea region (2019-2021) showed distinct seasonal activity patterns. Hazelnut phenology in Türkiye advances 6 weeks earlier than in Oregon with higher heat accumulation sustaining BMSB activity post-harvest. Semi-field cage experiments conducted in 2022 in Türkiye quantified insect-induced damage in relation to nut development. Five distinct damage types were identified: shell malformation (4.7%) in May-June, blank black shell (2.2%) and empty kernel (6.5%) in June, shriveled kernel (8.4%) in late June-mid-July, and corked kernel (10.5%) in July-August. A single adult was capable of damaging up to 537 nuts per season, with losses reaching 85% during the kernel expansion stage. Damage increased progressively through the season, with total damage 1.6-fold higher during kernel expansion compared to early development. Corked kernel damage was uniquely associated with BMSB feeding, confirming its diagnostic value. Findings demonstrate that BMSB injury is strongly shaped by the timing of insect activity relative to hazelnut phenology, with peak mid- to late-season activity driving greater losses, particularly in late-maturing cultivars. By linking damage types with per-capita impact, this study defines critical intervention windows for integrated pest management and highlights the need for adaptive forecasting tools that integrate pest biology, climate, and crop phenology.

Faba bean (Vicia faba L.) is an increasingly important pulse crop in Western Canada, but its production is threatened by Lygus spp. (Hemiptera: Miridae), which cause pod and seed damage through piercing-sucking feeding. This study examined the relationship between Lygus feeding duration, insect density, and the extent of scarring damage in faba bean seeds using complementary no-choice and electrical penetration graph (EPG) experiments. In no-choice assays, single adults of L. lineolaris and L. elisus confined to plants for 1, 3, 24, or 48 h produced significantly increasing damage over time (F = 6.24; P < 0.001), reaching the Canadian Grain Commission's 1% downgrading threshold after only 3 h of feeding. Species did not differ in damage potential. EPG recordings of L. lineolaris feeding revealed 3 main probing waveforms: cell rupture (CR), transition (T), and ingestion (I), with nymphs spending longer in CR and I phases than adults, although waveform type, not life stage, significantly affected feeding duration. McBryde staining detected salivary deposits in a limited number of pods and seeds, primarily from males, suggesting differences in salivation behavior among life stages. Collectively, these findings demonstrate that brief feeding periods by Lygus can cause economically significant damage to faba bean seeds, highlighting the importance of monitoring pest activity and minimizing feeding duration to reduce quality losses. The integration of EPG behavioral data with seed damage assessments provides a basis for establishing feeding-time thresholds to guide faba bean pest management.

Megalurothrips usitatus (Bagnall) (Thysanoptera: Thripidae), a major pest of leguminous crops in the Asian tropics, was first reported in Florida in 2020 and has since spread across Central America and the Caribbean. To control M. usitatus, Florida snap bean growers face higher production costs from increased insecticide use. To achieve more effective and sustainable management of M. usitatus, integrated approaches, including biological control, are needed. This study evaluated 2 commercial predatory mites, Amblyseius swirskii (Athias-Henriot) and Neoseiulus cucumeris (Oudemans) (Mesostigmata: Phytoseiidae), as biological control agents against M. usitatus through leaf disk bioassays and growth room cage studies. In the leaf disk bioassays, both predators showed high survival while feeding on M. usitatus, with daily oviposition rates of 1.07 for A. swirskii and 1.48 for N. cucumeris, and consumed 3 to 4 first instar larvae per day. Growth room cage studies evaluated whether these predatory mites could suppress M. usitatus on Phaseolus vulgaris plants. Weekly evaluations over 4 wk showed that A. swirskii significantly reduced M. usitatus population by approximately 75% by week 4. However, mean thrips densities remained high, with 101.2 ± 31.2 individuals per plant (mean ± SE), and significant plant damage was observed. Neoseiulus cucumeris did not significantly reduce thrips populations compared to control plants. This study provides evidence that A. swirskii can reduce M. usitatus populations on P. vulgaris plants under these conditions, but suppression remained limited, indicating that further work is needed to improve effectiveness.

Dioryctria abietella Denis & Schiffermüller (Lepidoptera: Pyralidae) is an oligophagous forest pest causing substantial ecological and economic damage to coniferous trees in Korea, yet its population genetic structure remains poorly understood. Here, we analyzed genetic diversity, population structure, and gene flow in 153 adult males from seven populations across South Korea using ten newly developed EST-SSR markers. All loci showed clear amplification, high polymorphism, and no linkage disequilibrium, confirming their suitability for population genetic analyses. Genetic diversity was generally high, although some locus-population combinations deviated from the Hardy-Weinberg equilibrium. Population genetic analyses revealed significant geographic structuring, with STRUCTURE, principal coordinate analysis, and UPGMA consistently identifying two major clusters: a northern-central mainland cluster and a distinct southern cluster including Gwangju and Jeju Island. A significant isolation-by-distance pattern indicated predominantly localized, short-range dispersal. Jeju Island population exhibited the strongest genetic differentiation and minimal gene flow, consistent with an oceanic barrier, whereas the Gwangju population showed moderate differentiation associated with historical founder effects rather than ongoing connectivity. In contrast, the Chungju population displayed high allelic richness, strong directional gene flow, and a modest heterozygote deficit, consistent with a weak Wahlund effect caused by admixture. AMOVA detected significant host-associated differentiation, however, the host plant explained only a small proportion of genetic variance, indicating a stronger influence of geography. Overall, these results demonstrate that spatial isolation and regional connectivity primarily shape D. abietella populations in Korea, providing a genetic basis for region-specific pheromone-based monitoring and management strategies.

The prohibition of straw burning for sugarcane harvesting facilitates the accumulation of organic matter in the soil, creating a microhabitat favorable to the survival of pests, such as the sugarcane billbug Sphenophorus levis Vaurie (Coleoptera: Curculionidae). This condition may also modify S. levis behavior, especially dispersal in sugarcane fields. As the inefficiency of the control tactics currently employed has turned this species into a key pest in the crop, straw management could be an alternative to S. levis management. In this study, we evaluated the effect of sugarcane straw management on S. levis dispersal under three conditions: (i) full straw, (ii) windrowed straw in the sugarcane interrow, and (iii) removed straw using the capture-release-recapture technique. The maximum distance traveled by the S. levis varied from 1.5 to 6.7 m in 11 d, depending on straw management, with more restricted mobility when the straw was completely removed. The direction of movement was significantly influenced by straw removal, with a higher number of S. levis recaptured in the same row of sugarcane where insects were released (within-row). Males and females exhibited similar patterns, with greater dispersal activity during the first few days after release. The presence of straw favored the movement of S. levis, whereas its total removal or windrowing restricted its dispersal. Thus, straw removal from sugarcane rows is a potential strategy for managing this pest. These results underscore the importance of cultural management as an integrated pest control strategy.

The spotted-wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), has become a global invasive pest of soft-skinned fruits over the past decade. Researchers have investigated various biological control agents and their potential applications for D. suzukii management. This special collection summarizes recent advances and highlights major achievements in the biological control of D. suzukii. These include early-stage releases of the introduced Asian larval parasitoid, Ganaspis kimorum Buffington (Hymenoptera: Figitidae), in the United States and Europe; the adventive establishment of another key Asian larval parasitoid, Leptopilina japonica Novković & Kimura (Hymenoptera: Figitidae), in North Amreica and Europe; methods for the cold storage of G. kimorum; effective sampling techniques for assessing the presence, relative abundance, and seasonal phenology of figitid parasitoids; the potential compatibility of other biological control agents (entomopathogens) with parasitoids; and assessment of specific insecticide impacts on common parasitoids. Finally, this special collection concludes with a proposed research, development, and implementation roadmap to improve biological control strategies for D. suzukii.

The economic impacts of Huanglongbing disease have prompted global surveillance of citrus psyllid vectors. While yellow sticky traps (YSTs) are widely used to detect pests such as the African citrus psyllid (Trioza erytreae) and the Asian citrus psyllid (Diaphorina citri), alternative methods may capture unique species and greater taxa richness and abundance, which could impact downstream species identification and diagnostics. We assessed psyllid richness and abundance across 4 sites within major citrus-growing regions of eastern Australia, and found that combining hand sampling with YSTs captured more species compared to light trapping and pan traps, but all sampling techniques collected unique taxa. Species were identified via an integrative taxonomy approach combining host plant data, morphology, and DNA sequences. We generated 196 cytochrome oxidase reference sequences from 87 species, 27 genera, and 5 families. Of these, 65 morphospecies and a described species were previously unrecorded in public DNA databases. This allowed us to build a baseline reference for eastern Australian native psyllids found around citrus orchard environments, thereby enhancing species-level molecular identification, and strengthening surveillance and biosecurity in Australia.

Climate change profoundly alters the geographical distribution and ecological adaptability of species, posing significant challenges to the spatial dynamics of pests and their natural enemies. To assess the potential impacts of climate variability on the efficacy of biological control, this study employed the MaxEnt model to project the current and future suitable habitats of the major agricultural pest Frankliniella tenuicornis and its natural antagonists Orius insidiosus and Ceranisus menes. The findings indicated that under future climatic scenarios, the potential distribution of F. tenuicornis is likely to expand, whereas the habitats of O. insidiosus and C. menes are expected to remain relatively stable or contract. Habitat overlap analysis revealed a considerable spatial congruence between the pest and its natural enemies, highlighting their potential to regulate pest populations through ecological interactions. Furthermore, under different emission pathways, the centroid of suitable habitats for F. -tenuicornis is projected to shift markedly westward and generally towards higher latitudes, while the displacement of centroids for the two natural enemies is comparatively minor. These results provide a comprehensive evaluation of the spatial dynamics of pests and their antagonists under climate change, offering theoretical foundations for optimizing biological control strategies, implementing targeted pest management practices, and safeguarding ecosystem stability.

Pear psylla, Cacopsylla pyricola (Förster), is a key pest of pears in the Pacific Northwest United States. Overwintering adults (winterforms) recolonize orchards in late winter from habitat outside orchards. To reduce winterform colonization and subsequent damage, sprays of the repellent particle film, kaolin clay, are recommended from late dormant through bloom. However, many pear growers struggle to make early sprays due to the danger of driving tractors over hilly terrain with lingering winter moisture. To address this challenge, we tested fall applications of kaolin (Surround WP) for suppression of pear psylla the following spring. Experiments were performed on potted trees and commercial orchard-sized plots, with fall kaolin treatments made at 112 kg/ha (120 g/L). Pear psylla adult and egg densities were measured by visual counts, and kaolin residue stability was assessed by relative whiteness of branches using ImageJ. In the days immediately after kaolin applications (fall and spring), kaolin significantly reduced pear psylla adult numbers and increased branch whiteness. Fall kaolin residues visibly declined over the winter, but branches often remained significantly whiter than checks at spring assessments. Likewise, fall kaolin often resulted in significantly fewer adults and eggs than checks the following spring. This study demonstrates that residues from fall-applied kaolin can remain through the winter and reduce pear psylla colonization the following spring. This tactic will be advantageous in orchards that are difficult to spray in early spring, and as a general addition to the pear integrated pest management toolkit.