This study describes Syntomernus ningbonensis sp. nov. (Hymenoptera: Braconidae, Braconinae), a new species of Braconinae reported from China. This parasitoid wasp attacks cynipid gall wasps (Cynipidae) on Rosa multiflora leaves. Adult wasps emerge from host galls between late July and early October, with typically 3-5 conspecific adults emerging from a single gall. Phylogenetic relationships between the new species and S. flavus Morley, as well as other known Syntomernus species were inferred using partial mitochondrial cytochrome c oxidase subunit I (COI) gene sequences. Additionally, a new combination is proposed: S. garugaphagae (Ranjith & Quicke, 2016), comb. nov.

Plants possess conserved immune systems to defend against herbivorous insects. In response, insects secrete saliva to manipulate host cell biology, with many salivary proteins being species-specific. The mechanisms by which different insects, armed with distinct salivary components, counteract the conserved plant immune systems are not well understood. Here, we describe how 2 salivary effectors from the brown planthopper Nilaparvata lugens and the bean bug Riptortus pedestris target pathogenesis-related germin-like proteins (GLPs) in rice and soybean. In N. lugens, NlGTSP is expressed exclusively in the salivary glands and is secreted into host plants during feeding. Its knockdown significantly reduces phloem feeding and reproduction, whereas overexpression in rice enhances insect performance and rescues NlGTSP deficiency. NlGTSP partly modulates defenses by interacting with plant GLPs and inhibiting their enzymatic activity. In R. pedestris, the salivary protein RpGDSP lacks sequence or structural similarity to NlGTSP but also targets GLPs, promoting their degradation via the ubiquitin pathway to enhance feeding. Collectively, our findings reveal a functional analogy between salivary effectors from different insects that regulate core plant defense genes through distinct mechanisms.

Plants utilize receptor-like proteins and receptor-like kinases (RLPs/RLKs) to perceive and respond to a wide variety of invading pathogens and insect herbivores. While the strategies employed by microbial pathogens to suppress plant immunity have been well characterized, it remains unclear how herbivorous insects counteract receptor-mediated defenses. Here, we show that salivary effectors evolve independently in whiteflies and planthoppers to dampen RLP4-mediated plant immunity. RLP4, as a leucine-rich repeat RLP (LRR-RLP), confers plant resistance against herbivorous insects by forming the RLP4/SOBIR1 complexes. In the whitefly Bemisia tabaci, BtRDP, the Aleyrodidae-specific salivary sheath protein, interacts with RLP4 from multiple plant species and promotes its ubiquitin-dependent degradation. Overexpression of NtRLP4 in transgenic plants exerts a detrimental effect on B. tabaci by exploiting the crosstalk between the salicylic acid and jasmonic acid pathways. Conversely, overexpression of BtRDP or silencing of NtRLP4 effectively alleviates such negative effects. In planthopper Nilaparvata lugens, the Delphacidae-restricted salivary protein NlSP104 also targets and promotes the degradation of OsRLP4 from rice plants. These findings reveal convergent evolution of salivary proteins in insects and underscore the complex interactions between plants and herbivorous insects.

The insect pretarsi are the sites of direct contact with the proximal environment. Aspects of pretarsal structures have been described in the literature. Comprehensive and detailed histological analyses of the pretarsal composition depicting the interaction of the different types of outside and inside tissues in insects are, however, anecdotal. Here, we present a tri-dimensional image of the tarsal ends of the housefly Musca domestica at the ultrastructural level using focussed-ion beam combined with scanning electron microscopy. In particular, we find that the different functional elements of the pretarsus have distinct cuticle thicknesses. In detail, the cuticle is thin at the joint to the fifth tarsomere, thickens in the dorsal claws and the ventral unguitractor plate; the ventral pulvilli, again, have a rather thin cuticle with the basis of their tenent acanthae (adhesive cuticle protrusions) arranged like roof tiles before the shafts protrude forming the adhesive acanthal cushion. Inside the cuticular tube, we discerned a composite filament with the distal end of a large gland, paired bundles of axons projecting into the claws but not the pulvilli and a tracheal tube. These elements are associated with the cuticular unguitractor tendon in the fifth tarsal subsegment that bridges to the external cuticle via a possibly flexible membranous cuticle. These data will serve in studying the pretarsal function regarding its interaction with the environment associated with its different structures in molecular and reverse genetic experiments.

IntroductionTicks are hematophagous ectoparasites that must overcome significant physiological challenges during blood feeding. These include managing oxidative stress, detoxifying host-derived molecules, and reallocating energy to support digestion, tissue remodeling, and reproduction.MethodsIn this study, we conducted a de novo transcriptome assembly and genome-wide transcriptional profiling of female Ixodes persulcatus ticks at three key feeding stages: unfed, semi-engorged, and fully engorged. Functional annotation and Gene Ontology (GO) enrichment analyses were conducted to characterize stage-associated transcriptional changes, with a focus on metabolic detoxification and antioxidant systems.Results and discussionWe generated a reference transcriptome containing 56,900 unigenes. Comprehensive analyses of metabolic detoxification and antioxidant systems revealed species-specific expansions in key supergene families such as cytochrome P450s and glutathione S-transferases. The expression profiles across feeding stages revealed pronounced physiological changes in response to blood meal, and GO enrichment analysis showed that these changes were mainly involved in blood acquisition, nutrient metabolism, respiratory processes, hormone synthesis, egg development, immune responses, ROS detoxification, transcription and translation. These findings offer new insights into the molecular physiology of tick hematophagy and provide a valuable resource for future studies on stress responses and metabolic regulation in ticks.

This study presents a comprehensive three-dimensional anatomical atlas of the adult Nilaparvata lugens using micro-CT and FIB-SEM. The reconstructions reveal the spatial organization of the flight muscle system, digestive tract, reproductive organs, and nervous system. The indirect flight muscles, including dorsal longitudinal and dorsoventral muscles, are structurally similar between sexes but show size differences in certain components. The female reproductive system occupies most of the abdominal cavity, reflecting high fecundity, while the male reproductive system features a specialized ejaculatory duct associated with muscular control. Notably, the genital coupling during copulation involves a sophisticated interlocking structure, ensuring stable alignment and preventing separation. These structural insights offer a holistic framework for understanding dispersal and reproduction in N. lugens, with implications for developing novel pest management strategies.

Long noncoding RNAs (lncRNAs) are increasingly recognized as sources of functional peptides that regulate plant development and immunity, yet little is known about whether lncRNA-encoded peptides participate in antiviral defense. Through transcriptomic analysis combined with peptide-coding potential prediction, we identified wheat lncRNA19864, which is highly expressed in wheat yellow mosaic virus (WYMV)-resistant cultivars and encodes a 39-amino-acid peptide, TaLEP1. Genetic manipulation of TaLEP1 expression revealed that TaLEP1 acts as a positive regulator of wheat resistance to WYMV. Mechanistically, TaLEP1 forms oligomers and interacts with both the host autophagy factor TaATG18a and the viral replicase NIb, thereby facilitating NIb recruitment to autophagosomes for degradation. Disruption of TaLEP1 oligomerization or TaATG18a function impaired NIb degradation and compromised TaLEP1-mediated antiviral resistance. Notably, TaLEP1 also confers resistance to other Potyviridae members, including turnip mosaic virus and soybean mosaic virus, by similarly targeting their NIb proteins for degradation. These findings demonstrate that an lncRNA-encoded peptide is involved in plant antiviral immunity and offer a potential strategy for engineering broad-spectrum virus resistance in crops.

The predatory bug Eocanthecona furcellata (Hemiptera: Pentatomidae) is an important natural enemy of agricultural and forest pests. In this study, we assembled a chromosome-level genome of E. furcellata using a combination of Illumina short-read sequencing, PacBio HiFi long-read sequencing, and Hi-C technology. The assembled genome has a total size of 1140.70 Mb, with a scaffold N50 of 154.55 Mb. The genome exhibits a high level of completeness, with 99.7% of conserved genes detected. Repetitive elements account for 64.33% of the genome. A total of 22,534 protein-coding genes were predicted, of which 20,803 were successfully annotated. This high-quality genome assembly provides a valuable resource for future research on the biology and ecological functions of this predatory insect.

Abstract Plant viruses that rely on insect vectors for persistent transmission are widespread globally and inflict severe yield losses in agricultural crops. Through long‐term coevolution, these viruses and their insect vectors have developed complex interactions that maintain a balance between vector fitness and efficient virus transmission. Furthermore, accumulating evidence indicates that the innate immune system plays a pivotal role in mediating these intricate interactions. In this review, we highlight two key aspects of the virus–vector interplay: (1) persistently transmitted viruses exploit host factors to overcome transmission barriers; and (2) molecular recognition triggers antiviral immunity and subsequent viral counter‐defense. Elucidation of these virus–vector interactions offers critical insights for the development of novel strategies to disrupt viral transmission cycles.

Saliva plays a crucial role in mediating plant-insect interactions, yet the functional diversity of salivary proteins remains poorly understood. Here, we identify NlSP6935, a salivary gland-specific protein conserved among rice planthoppers but absent in bamboo-feeding relatives. Silencing NlSP6935 causes severe lethality, feeding impairment, and infertility in Nilaparvata lugens, independent of host plant resistance. Transient expression assays reveal that NlSP6935 suppresses H2O2 accumulation in plants, while overexpression in rice downregulates terpenoid biosynthesis and enhances host attractiveness. However, transgenic NlSP6935 plants only weakly rescue RNAi-induced lethality, demonstrating its dual role in insect physiology and plant defense suppression. Our findings reveal a novel effector essential for both planthopper survival and host adaptation, providing new insights into pest control strategies.

Long noncoding RNAs (lncRNAs) are increasingly recognized as a source of functional peptides involved in plant development and immunity, yet little is known about whether lncRNA-encoded peptides participate in antiviral defence. By transcriptome analysis with peptide-coding potential prediction, we identify lncRNA19864, which is highly expressed in wheat yellow mosaic virus (WYMV)-resistant cultivars and encodes a 39-amino-acid peptide, TaLEP1. Genetic manipulation of TaLEP1 expression showed that TaLEP1 as a positive regulator of wheat resistance to WYMV. Mechanistically, TaLEP1 forms oligomers and interacts with both the host autophagy factor TaATG18a and the viral replicase NIb, thereby facilitating NIb recruitment to autophagosomes for degradation. Disruption of TaLEP1 oligomerization or TaATG18a function impaired NIb degradation and compromised TaLEP1-mediated antiviral resistance. Notably, TaLEP1 also confers resistance to other Potyviridae members, including Turnip mosaic virus (TuMV) and Soybean mosaic virus (SMV), by similarly targeting their NIb proteins for degradation. Accordingly, lncRNA-encoded peptide is involved in plant antiviral immunity. Our results offer a potential strategy for engineering broad-spectrum virus resistance in crops.

The Toll7 pathway is crucial in defending against diverse pathogenic microorganisms, including viruses. This study reveals that a plant virus (rice stripe virus, RSV) infection activates Toll7-mediated antiviral response in the insect vector Laodelphax striatellus. We identified a specific interaction between the TIR domain of Toll7 and RSV glycoprotein (Gc). Furthermore, Toll7 silencing significantly enhanced RSV replication and acquisition, suggesting its antiviral role in L. striatellus. Transcriptomic analysis indicated that Toll7 negatively regulates the PI3K-Akt-mTOR pathway, a key autophagy regulator. Toll7 knockdown upregulated the expression of PI3K, Akt and mTOR; simultaneously, autophagy-related genes (Atg3, Atg5, Atg8, Atg9, Torc1 and ULK1) were downregulated and autophagy inhibitor Sqstm1 was upregulated. Conversely, silencing PI3K, Akt or mTOR suppressed RSV replication, highlighting the essential role of this pathway in viral persistence within its vector. These findings demonstrate that Toll7-mediated inhibition of the PI3K-Akt-mTOR pathway activates autophagy, restricting RSV replication in L. striatellus. This study uncovers a conserved Toll7-dependent antiviral mechanism modulating autophagy to inhibit viral infection, offering new insights into the co-evolutionary dynamics between plant viruses and insect vectors.

The insect microbiome profoundly influences host physiology and ecology, yet its composition and evolutionary dynamics in thrips remain poorly understood. Here, we present a systematic characterization of thrips-associated microbiomes through integrated metagenomic and culture-based approaches. Our analysis reveals that thrips microbiomes are dominated by both intracellular symbionts (e.g., Wolbachia and Spiroplasma) and extracellular taxa (e.g., Serratia, Pantoea, and Acinetobacter), with species-specific compositions exhibiting frequent gains and losses of bacterial lineages. We demonstrate that thrips microbiomes exhibit low interspecific microbial sharing, forming host-specific bacterial communities with minimal overlap between species. To address methodological challenges in microbiome research, we developed a dual-sequencing framework combining short-read sequencing (for comprehensive taxonomic detection) and long-read sequencing (for genomic verification), enabling the reconstruction of high-quality metagenome-assembled genomes that validated short-read findings. Furthermore, we isolated and sequenced the complete genomes of two dominant extracellular symbionts-Pantoea dispersa and Serratia marcescens-and performed pan-genome analyses. These revealed small core gene sets and expansive accessory genomes, including host-specific functional genes (e.g., hydrolases and neurotoxic N-acetyltransferases) likely involved in host adaptation. Our study provides a foundational genomic resource and a robust analytical pipeline for dissecting thrips microbiome evolution, with implications for understanding insect-microbe interactions and symbiont-mediated adaptations.

Frankliniella occidentalis (western flower thrips) is a globally destructive pest causing major crop losses via oviposition, feeding, and plant virus transmission. Previous work has focused on its reproductive physiology and behavior, but comprehensive 3D structural knowledge remains limited. We used volume electron microscopy to achieve nanoscale 3D visualization of the reproductive systems in both sexes, providing the first high-resolution, in situ reconstruction, and establishing a new anatomical framework for insect reproductive physiology. Males exhibit extreme miniaturization, with reproductive organs occupying just 1.45% of body volume yet retaining full function within a compact abdomen. Females possess eight tightly interwoven ovarioles that maximize coelomic space for oocyte maturation, maintaining a slender form while housing large eggs-reflecting an evolutionary trade-off between reproductive efficiency and body size. Our reconstructions resolve a key ambiguity: the female accessory glands are a pair of fused, S-shaped structures joined by an internal duct opening near the ovipositor base. Quantitative analysis reveals the first complete germ cell census, with asymmetric ovary cell numbers suggesting an adaptive strategy for sustained fecundity. By integrating detailed morphology with systematic quantification, this study creates a foundation for research in functional morphology and for developing reproduction-targeted pest management. The structural insights enable precise strategies to disrupt thrips reproduction and reduce virus spread. Beyond advancing pest control innovation, the findings serve as a valuable educational and reference resource in insect morphology.

Abstract Southern rice black-streaked dwarf virus (SRBSDV) is a destructive pathogen of rice that is transmitted by the white-backed planthopper (WBPH, Sogatella furcifera ). Identifying infectious reservoirs within the SRBSDV cycle is critical for developing effective disease management strategies. This research identifies Chinese sprangletop ( Leptochloa chinensis ), a noxious weed commonly found in rice ecosystems, as a previously unrecognized natural host of SRBSDV. SRBSDV infection was detected in L. chinensis samples collected from rice paddies exhibiting SRBSDV symptoms. Transcriptomic analyses, observation of SRBSDV virions, and typical profiles of SRBSDV-derived small interfering RNAs provided evidence of active, low-level, and asymptomatic viral infection. Genomic comparisons revealed minor genetic divergence in the viral RNA-dependent RNA polymerase (RdRP) gene, suggesting host-specific adaptation without compromising transmissibility. Further investigations using transmission experiments demonstrated that WBPHs microinjected with SRBSDV obtained from L. chinensis efficiently transmitted the virus to rice seedlings at a rate of 35.7%. This study emphasizes the necessity of integrating weed management into SRBSDV control strategies to disrupt viral reservoirs and mitigate outbreaks.

Effectors secreted by pathogens or insects manipulate host plant cellular processes depending on their target destination. However, our current knowledge regarding nucleus-localized effectors from herbivorous insects remains limited. Here, we demonstrate that Nilaparvata lugens evolve a nuclear localization signal (NLS)-containing salivary effector NlAMSP that is specialized for targeting host plants. NlAMSP resides in the cytoplasm of insect salivary glands, but, upon secretion, migrates into the nucleus of rice cells. This nuclear translocation is enabled by the cleavage of its signal peptide, allowing the NLS-dependent import via the host importin-α/β pathway. SUMOylation at sites within the NLS is essential for the NlAMSP function, enhancing its nuclear localization and protein stability by preventing autophagy-associated degradation. In plants, NlAMSP interacts with the histone deacetylase OsHDA706 and redirects it from the cytoplasm to the nucleus, thereby disrupting its interaction with the JA biosynthesis regulator OsLOX14 in the cytoplasm. This interference reduces OsLOX14 accumulation and suppresses the JA-associated defense responses. Furthermore, nucleus-localized OsHDA706 diminishes histone H4K5ac and H4K8ac, thereby suppressing the expression of NLR and WRKY genes essential for rice resistance to N. lugens. Our findings uncover a mechanism by which an insect effector manipulates host nuclear trafficking and epigenetic regulation to facilitate herbivory.

The SNARE protein USE1 plays a critical role in retrograde membrane traffic from the Golgi to the endoplasmic reticulum (ER) in yeast, yet its function in insects remains unclear. This study investigates the role of the RpUSE1 gene in the agricultural pest Riptortus pedestris. Domain analysis confirmed that RpUSE1 is a 248-amino-acid SNARE protein containing a C-terminal transmembrane domain and a SNARE motif featuring a conserved aspartate residue at the central "0" layer. It is ubiquitously expressed in R. pedestris, with the highest transcript levels in the female reproductive system. RNAi-mediated knockdown of RpUSE1 severely impaired nymph survival and development. Moreover, silencing RpUSE1 in adult females completely disrupted egg development and caused structural disorder of the lateral oviducts, including ER disorganization. Notably, there was a significant accumulation of lipid droplets within the lateral oviduct lumen. In contrast, silencing RpUSE1 in male adults did not affect fertility. These findings demonstrate that RpUSE1 is essential for nymphal survival and female reproductive success, highlighting its crucial role in maintaining organelle structure and intracellular transport.

Insect-specific and insect-borne viruses (particularly RNA viruses) may pose a serious threat to global rice production. However, the effects of geographic genetic divergence and ecological viral communities in shaping insect viromes remain poorly understood. The striped stem borer, Chilo suppressalis—a notorious chewing pest widely distributed across China—serves as an ideal model to study RNA virus evolution and cross-species transmission dynamics in rice ecosystems. Meta-transcriptomic sequencing analysis of 48 C. suppressalis samples collected nationwide revealed four major geographic populations and identified 20 high-abundance viruses (15 novel). These include the widespread core virus Hangzhou sesamia inferens peribunyavirus 1 and Chilo suppressalis sedoreo-like virus 1, as well as several climate-adapted viruses that may represent extreme-environment specialists. Diversity analyses revealed that the geographic genetic divergence of C. suppressalis influences viral species composition but not the overall virome structure. Parallel sequencing of 5 Cotesia chilonis (endoparasitoid) samples revealed 8 high-abundance viruses (5 novel). Significant variations in distribution patterns, viral loads, and vsiRNA profiles within C. suppressalis–C. chilonis parasitic system suggested host-driven adaptive evolution of these viruses. Co-occurrence network analysis demonstrated that sympatric species (such as Sesamia inferens and rice planthoppers) and their host plant, rice, significantly influence C. suppressalis virome composition, highlighting cross-kingdom viral transmission dynamics. This study elucidates the synergistic roles of geographical divergence and ecological viral communities in driving virome diversity in C. suppressalis. Our findings advance the understanding of virus-host coevolution in agricultural ecosystems and provide a framework for developing integrated strategies targeting both insect pests and their viral pathogens in rice cultivation.

Gall-forming insects manipulate host plants through the proteins present in their saliva, which play essential roles in reprogramming plant cells. In this study, we utilized an integrated transcriptomic and proteomic approach to explore the salivary proteome of camphor psylla (Trioza camphorae). Transcriptomic analysis identified 97 secretory proteins that were abundantly and specifically expressed in the salivary glands. Proteomic analysis further revealed 69 secretory proteins in the salivary glands and 21 proteins in the secreted saliva. Collectively, 168 proteins were identified as potential salivary components of T. camphorae. Comparative analysis of T. camphorae saliva with other herbivorous insects unveiled 66 conserved salivary proteins. Interestingly, in contrast to the closely related Diaphorina citri, which lacks gall formation ability, 68 T. camphorae salivary proteins exhibited species-specificity. Due to the challenges of overexpressing proteins in camphor trees, we used Nicotiana benthamiana as a heterologous system to preliminarily assess salivary protein function. Three proteins were found to alter N. benthamiana physiology, though their specific roles in T. camphorae-camphor tree interactions require further investigation. Our findings contribute to a deeper understanding of the molecular mechanisms underlying insect-induced gall formation, and might be useful in the future management of forest pests.