Search Results (189)

The diamondback moth, Plutella xylostella, is a major pest of cruciferous crops, and predatory insects are important candidates for its biological control. However, predator performance may vary substantially across developmental stages, complicating stage-specific evaluation and cross-species comparison. Here, we quantified corrected prey consumption and functional response patterns of three insect predators, Eocanthecona furcellata, Hierodula patellifera, and Paratenodera sinensis, across predator developmental stages, prey stages, and prey densities under laboratory conditions. Functional response types were classified using logistic regression, and model parameters were estimated using nonlinear functional response models. Corrected prey consumption generally increased with prey density, but the strength of density-dependent differentiation varied among predator instars and prey stages, with clearer treatment separation typically observed in later instars and adults than in early instars. Across 37 predator–prey-stage combinations, Type II-like functional responses predominated in 29 combinations, whereas 6 were classified as Type III-like and 2 were ambiguous. Strict matched-subset analysis further showed that relative differences among predator species were stage-dependent, indicating that cross-species comparisons were sensitive to predator developmental stage and the degree of experimental matching. These results indicate that the three predators have stage-dependent potential for the biological control of P. xylostella and provide a laboratory-based basis for their future evaluation and application under field conditions. Full article

As food security gains increasing attention, automated pest monitoring is crucial for agricultural early warning systems. However, in practical light-trap capturing sensors, the extremely small scale of pests and complex background interference, such as unexpected reflection and occlusions, severely undermine the performance of existing models, resulting in frequent missed and false detections. To deal with these challenges, this study proposes EP-YOLO, an enhanced lightweight detection architecture based on YOLOv8n. Specifically, to retain the spatial pixels of micro-targets during downsampling and isolate pest features while eliminating background noise without compromising channel information, the Spatial-to-Depth Convolution (SPD) module and the Efficient Multi-Scale Attention (EMA) module are introduced. We evaluate our model through experiments on Pest24, a dataset consisting of 24 tiny pest categories. The results demonstrate that EP-YOLO achieves a mAP@50 and mAP@50:95 of 70.5% and 47.3%, respectively, improving upon the baseline by 1.1% and 1.9%. Furthermore, EP-YOLO achieves a significant improvement in detecting certain extremely small pests. For example, Rice planthopper and Plutella xylostella show improvements of 8.4% and 3.1%, respectively, compared to the baseline. In conclusion, the physical limitations of detecting tiny pests are successfully overcome by EP-YOLO, providing a robust and deployable design for real-time agricultural monitoring systems. Full article

The diamondback moth (Plutella xylostella) is a devastating global pest of cruciferous crops. This study explores the potential of targeting the vacuolar ATPase subunit E (PxvATPaseE) for its control. We demonstrate that PxvATPaseE is essential for larval development, showing high expression levels in the midgut. RNA interference (RNAi)-mediated silencing of PxvATPaseE resulted in severe growth retardation and dose-dependent mortality, with higher dsRNA doses inducing more sustained effects. Furthermore, computational virtual screening of natural compound libraries identified a high-affinity binder of PxvATPaseE, such as periplocoside D. Our results demonstrate that PxvATPaseE is a promising molecular target for controlling P. xylostella, supporting a dual-strategy approach combining RNAi and targeted chemical inhibition for future pest management solutions. Full article

Milbemycin D is a promising 16-membered macrolide insecticide with reported superior efficacy, but its commercial development has been hindered by extremely low natural yields. This study aimed to construct a high-yielding microbial platform for milbemycin D production using combinatorial biosynthesis and advanced genome editing. An optimized CRISPR/Cas9-AcrIIA4 system was employed to seamlessly replace the aveA3 polyketide synthase (PKS) gene in the ivermectin B1b-producing strain Streptomyces avermitilis HU501 with the heterologous milA3 PKS from S. bingchenggensis. The engineered strain was validated genetically and metabolically, followed by high-throughput screening and fermentation optimization in various media. The biosynthesized compound was structurally confirmed by spectroscopy. Bioactivity was evaluated against Bursaphelenchus xylophilus, Hyphantria cunea, and Plutella xylostella. The engineered strain S. avermitilis HU501-M successfully shifted its major product to milbemycin D, reaching a final titer of 679.03 mg/L. Bioassays revealed that milbemycin D exhibited significantly enhanced potency, with LC₅₀ values 8–24% lower than those of milbemycin A3/A4. This work demonstrates an efficient CRISPR/Cas9-mediated PKS replacement strategy to achieve the high-yield production of milbemycin D, offering a promising microbial source and a generalizable framework for engineering complex polyketide pathways. This proof-of-concept establishes a foundation for future process development toward potential commercial application. Full article

The diamondback moth (Plutella xylostella) severely threatens global oilseed rape (Brassica napus L.) production. This study demonstrates that CRISPR/Cas9-mediated knockout of two homologous BnaFAH, involved in tyrosine degradation, confers enhanced Brassica napus resistance to Plutella xylostella under a 2-day short-day (SD2) photoperiod. Multi-omics analyses revealed that this resistance is associated with a coordinated response: BnaFAH deficiency triggers reactive oxygen species (ROS) accumulation, which is closely associated with activating the jasmonic acid (JA) biosynthetic and signaling pathways. This led to significant upregulation of key JA biosynthetic genes and accumulation of JA, its precursors (OPDA, OPC-4, and OPC-6), and bioactive conjugates (JA-Ile and JA-Phe). Pharmacological analyses support the central role of JA, as exogenous application of methyl jasmonate (MeJA) enhanced insect resistance, whereas the JA biosynthesis inhibitor DIECA suppressed resistance. Scavenging ROS with sodium selenite prevented both JA pathway upregulation and insect resistance, suggesting that ROS may act upstream to activate the JA biosynthetic and signaling pathways. These findings support a previously unrecognized “photoperiod-dependent ROS-JA” defense module, revealing how metabolic perturbation under specific environmental cues can be co-opted to enhance plant immunity, offering new targets for breeding resistant rapeseed varieties. Full article

Plutella xylostella (L.) (Lepidoptera: Plutellidae), the diamondback moth (DBM), is a cosmopolitan pest of brassicas. To validate and compare the performance of yeast-derived sex pheromone components with chemically synthesized ones, we studied the behavioral and electrophysiological responses (EAGs) of male DBM adults. In addition, using gas chromatography coupled with electroantennographic detection (GC-EAD), we examined whether any residual impurities present in yeast-derived pheromone components can be perceived by the insects’ antennae and are thus capable of interfering with normal behavior. Furthermore, we assessed the performance of the yeast-derived pheromones under field conditions through monitoring trials conducted in cabbage crops in Greece. Electrophysiological and behavioral assays revealed equivalent responses from the insects to both the yeast-derived (BIO) and chemically synthesized (CHEM) pheromone blends. Consistent with this, GC-EAD results showed no significant differences in antennal response to minor impurities present in the BIO blend compared to the CHEM blend. Finally, it was demonstrated that the binary pheromone blend—comprising (Z)-11-hexadecenal and (Z)-11-hexadecenyl acetate derived from (Z)-11-hexadecen-1-ol produced by yeast cell-factories—was as efficient and specific for trapping male moths in cabbage fields as the conventional ternary synthetic blend [(Z)-11-hexadecenal and (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol]. The yeast-derived mixture contained small amounts of unoxidized (Z)-11-hexadecen-1-ol due to incomplete oxidation. Full article

The diamondback moth, Plutella xylostella (L.), is a significant pest of brassica crops that is found across the globe. Due to the development of insecticide resistance, control tactics have shifted focus towards integrating pest management techniques such as biological control. Diadegma insulare (C.), Oomyzus sokolowskii (K.), and Microplites plutellae (M.) are parasitoids of P. xylostella found in the Eastern United States. From 2022 to 2025, we surveyed P. xylostella larvae and pupae in locations across Virginia to assess the current rates of parasitism in brassica fields. Specimens were brought to the laboratory and reared to assess parasitoid emergence rates. Only D. insulare specimens were found during the study. Adult P. xylostella, larvae and pupae, adult D. insulare, D. insulare pupae, unknown parasitoids, and unknown deaths were recorded and used to calculate the rates of parasitism at each location. We concluded that the parasitism rate varied by location and year, which was expected due to regional conditions and seasonality. Rates averaged between 30.1 and 65% by year, with the lowest individual rate being 15% in 2025 and the highest at 100% in 2022. This suggests that D. insulare is actively present in Virginia and could be a successful biological control agent when paired with other integrated pest management techniques to reduce P. xylostella populations. Full article

The importance of protein-based materials in agricultural pest control has received increasing attention in recent years. Herein, Plutella xylostella brush-border membrane vesicles (BBMVs) were used as a target to screen for human domain antibodies with insecticidal activity. Three rounds of panning of the phage display library yielded the domain antibody C4D, which competed with the Cry1Ac toxin to bind to P. xylostella BBMVs. Against P. xylostella larvae, the recombinant soluble C4D protein showed an LC₅₀ of 1.57 μg/cm² (95% fiducial limits: 0.83–2.54). Using pull-down assays and liquid chromatography–tandem mass spectrometry, we identified the C4D binding partner in P. xylostella midgut BBMVs to be a cadherin-like protein. Bio-Layer Interferometry assay revealed that the dissociation constant between soluble C4D and P. xylostella cadherin-like protein was 2.99 × 10⁻⁶ M. Thus, the present study explored strategies to generate insecticidal antibodies, and the human domain antibody C4D identified and characterized in this study can serve as a framework for generating novel insecticidal agents. Full article

Plutella xylostella, a major pest of cruciferous vegetables, depends predominantly on chemoreception to locate host plants. Legs are crucial in insect chemical perception, particularly during close-range and contact chemoreception. However, the molecular basis underlying the chemosensory repertoire in P. xylostella legs remains elusive. To address this, we sequenced chemosensory-related genes in diamondback moth legs. Sequencing identified 32 odorant binding protein (OBP), 18 chemosensory protein (CSP), 26 odorant receptor (OR), 20 gustatory receptor (GR), 15 ionotropic receptor (IR), and 3 sensory neuron membrane protein (SNMP) genes. Comparative analysis with antennal transcriptome data revealed three CSPs, seven ORs, and two GRs newly identified in the legs. Transcriptome analysis showed higher fragments per kilobase of transcript per million mapped reads values for CSPs than for other chemosensory-related gene families. Furthermore, qRT-PCR confirmed the highest expression of PxylCSP9 in the legs, suggesting its role in perceiving external compounds. Fluorescent binding assays revealed high binding affinity of PxylCSP9 for several host plant semiochemicals. Molecular docking predicted a hydrophobic binding pocket in PxylCSP9 with Met11, Leu13, and Leu43 frequently participating in ligand interactions. Our findings indicate that leg-enriched PxylCSP9 is pivotal for host plant recognition during close-range chemoreception, suggesting its potential as a molecular target for precision management through behavior-based strategies. Full article

The Diamondback moth (DBM), Plutella xylostella (L.), the most significant worldwide pest of Brassica crops, is notorious for resistance to a diverse number of insecticides. Field populations bioassayed in Georgia and Florida, USA, in 2018 were resistant to chlorantraniliprole but susceptible to cyantraniliprole. Subsequently, populations assayed in 2021, 2022, and 2023 were cross-resistant to both diamides. We used NextSeq analysis of the ryanodine receptor PxRyR, the target of diamides, to quantify target site mutations associated with resistance. Three populations sampled in 2018 had a high prevalence (75.0–98.3% of total reads) of the G4946E mutation, associated with resistance to chlorantraniliprole, and additionally, in one population, a very low (2.7%) prevalence of another mutation, I4790K, was associated with diamide cross-resistance. Populations sampled in 2021 had a decreased prevalence of G4946E (0.7 and 8.4%) and increased prevalence of I4790K (9.3 and 18.0%). The G4946E allele was almost absent (0.2% to 3.9%) in populations sampled in 2022 and 2023, while I4790K was present at frequencies from 34.1% to 84.0%. These data suggest a remarkable shift in PxRyR target site mutations, replacing G4946E with I4790K, which occurred between 2018 and 2022, and were associated with the recent occurrence of cross-resistance in DBM populations in the Southeastern USA. Full article

Targeting juvenile hormone esterase (JHE) is an emerging strategy to combat the broadly resistant pest, Plutella xylostella; this study employed transcriptomics to investigate the sublethal effects of the JHE inhibitor OTFP, revealing a non-monotonic dose response characterized by stronger transcriptional changes at lower concentrations, resulting in low mortality, prolonged pupation time, and increased pupal weight. The results from the Differentially Expressed Genes (DEGs) analysis revealed that the core effect of OTFP is the persistent perturbation of the “insect hormone biosynthesis” pathway and altered expression of components of the JH/20E axis; to cope with this stress, the larvae exhibited a dual defense associated with compensatory upregulation of JH-degrading enzyme genes to attempt to restore hormone homeostasis, and the activation of a broad-spectrum detoxification network to clear the compound. More critically, the developmental delay resulting from endocrine disruption KEGG-enriched growth-related pathways (amino-acid and central-carbon metabolism; ribosome biogenesis; aminoacyl-tRNA biosynthesis), consistent with a growth-permissive milieu during prolonged feeding. This study therefore elucidates a novel integrative regulatory network that links endocrine disruption, detoxification, and compensatory growth, revealing a complex physiological trade-off strategy in this pest that sacrifices developmental tempo for survival. Full article

G protein-coupled receptors (GPCRs) are considered the largest and most variable family of transmembrane receptors regulating physiological processes such as toxicological responses and insecticide resistance development. The present study investigated the responses of Methuselah (Mth), belonging to GPCR family B in the Diamondback Moth (DBM), Plutella xylostella, to chlorantraniliprole (CAP). Genome-wide identification and phylogenetic analysis of Pxmth genes revealed their evolutionary relationships and functional classifications. Expression profiling demonstrated significant overexpression of Pxmth2 in the CAP-resistant strain. Additionally, the tertiary and secondary structures of Pxmth2 were characterized, providing insights into its functional role. Silencing Pxmth2 via RNA interference (RNAi) reduced resistance of DBM to CAP and suppressed downstream stress-associated genes (CYP6B6, CYP6B7, CYP6BF1), increasing susceptibility to the insecticide. The function of Pxmth2 was further explored using a transgenic line of Drosophila melanogaster engineered to overexpress the gene; flies overexpressing Pxmth2 exhibited a significantly increased resistance to CAP compared to controls. These findings indicate that Pxmth2 contributes to CAP resistance in DBM and highlights potential molecular targets for improving pest management strategies. Full article

Cabbage (Brassica oleracea Linnaeus) is an important vegetable crop for food security and income generation for farmers in the Democratic Republic of Congo (DRC). However, production is severely undermined by a complex of insect pests. This study investigates farmers’ knowledge, perception, and pest management practices in key cabbage-growing areas surrounding Goma city in Eastern DRC. A total of 430 farmers were interviewed using a structured survey administered via the KoboToolbox platform. The diamondback moth (Plutella xylostella Linnaeus, 1758) and the cabbage aphid (Brevicoryne brassicae Linnaeus, 1758) were identified as the main pests, with peak incidences reported during the dry mid-season. Pest damages are most frequently observed at the post-transplanting and heading stages of cabbage. Although chemical control was the dominant strategy (69.4%), concerns arise due to the widespread use of moderately to highly hazardous insecticides, including pyrethroid, organophosphorus, and avermectin-based formulations. The insufficient use of personal protective equipment (PPE) and limited training on safe pesticide handling remain further challenges. While indigenous practices, such as crop rotation, handpicking of insects, and the use of botanical extracts, are employed to a lesser extent, awareness and implementation of biological control are almost nonexistent. The findings underscore the need to promote integrated pest management (IPM) approaches based on agroecological principles, including the safe use of (bio-)pesticides, training programs, and stakeholder engagement to enhance sustainable cabbage production. Full article

The diamondback moth, Plutella xylostella, is a major pest of brassica vegetables and oilseed crops, posing a serious threat to China’s grain and oil production. RNA interference (RNAi) has been developed as an efficient strategy to control pests. In this study, the effects of RNAi on P. xylostella were evaluated by injecting two doses of synthesized dsPxvATPasea. The transcripts of PxvATPasea were widely transcribed during different developmental stages from egg to adult. They were abundantly expressed in the hindgut and Malpighian tubules, compared with other tissue types. Introduction of 800 ng dsPxvATPasea in the fourth-instar larvae greatly reduced corresponding mRNA levels by 3.1 and 1.4 times on day 2 and 3, respectively, causing 66.6% mortality and 33.4% treated larvae pupated. Silencing PxvATPasea by injecting 1200 ng dsRNA significantly decreased the expression level by 5.0 and 2.0 times on the second and third day, leading to 79.2% larval lethality and 20.8% depleted larvae pupated. Moreover, introducing 800 ng or 1200 ng dsPxvATPasea finally reduced larval fresh weight by 22.1% and 28.8%, respectively. The results indicated that the silencing efficiency of PxvATPasea worked in a dose-dependent way. Consequently, PxvATPasea is a potential molecular target gene. Our findings will facilitate the application of RNAi technology to manage P. xylostella. Full article

To provide a scientific basis for pest control, this study evaluated the insecticidal activity of novaluron against the fall armyworm (Spodoptera frugiperda) and diamondback moth (Plutella xylostella). The leaf-dip method determined the toxicity of novaluron to second-instar larvae, while corn leaves and cabbage treated with sublethal (LC₁₀) and median lethal concentrations (LC₅₀) of novaluron were used to feed the larvae. Enzyme-linked immunosorbent assays (ELISA) measured the activities of detoxifying enzymes [carboxylesterase (CarE), cytochrome P450 (P450), glutathione S-transferase (GST), and acetylcholinesterase (AChE)] and ecdysteroid (Ecd) levels in the pests after 24 and 48 h of treatment. Results indicated that after 24 h, AChE was involved in diamondback moth metabolism and CarE activity was inhibited. After 48 h, P450 and GST participated in fall armyworm detoxification, whereas P450 and GST were active in diamondback moth detoxification, with other enzyme activities normalizing. Novaluron also altered Ecd levels in both pests. These results demonstrate differing detoxification mechanisms in fall armyworm and diamondback moth, likely due to their unique physiological and ecological traits, and support the potential use of novaluron in pest management strategies. Full article