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Simple Summary: Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is an important invasive pest of small soft-skinned fruits globally. The combined application of insecticides and natural enemies can effectively control D. suzukii and reduce chemical insecticide residues. The pupal parasitoid Trichopria drosophilae (Hymenoptera: Diapriidae) has been evaluated as a biological agent of D. suzukii. However, little is known about the toxicity of common insecticides in T. drosophilae. Thus, this study assessed the toxicity of eight common insecticides against D. suzukii in fruit orchards and the effects of semilethal and sublethal doses on T. drosophilae. Emamectin benzoate, spinetoram, lambda-cyhalothrin, abamectin, and sophocarpidine showed high toxicity in adults and larvae of D. suzukii. The toxicities of lambda-cyhalothrin and imidacloprid in T. drosophilae adults were higher than those of the other six insecticides. Exposure to chlorantraniliprole, emamectin benzoate, sophocarpidine, abamectin, azadirachtin, and spinetoram at semilethal and sublethal doses decreased the parasitism of T. drosophilae or eclosion of the next generation. In conclusion, some insecticides at the recommended dose applied for D. suzukii had no effect on the survival of T. drosophilae adults, but insecticide residues can affect T. drosophilae development. The pupal parasitoid Trichopria drosophilae (Hymenoptera: Diapriidae) has been evaluated as a biological agent of Drosophila suzukii. Integrated pest management strategies mostly rely on combined application of multiple insecticides and natural enemies. This study assessed the toxicity of eight common insecticides against D. suzukii in fruit orchards and the effects of semilethal and sublethal doses on T. drosophilae. The eight insecticides had higher toxicities to D. suzukii larvae with lower LC50 values than those for adults. Adults and larvae showed high susceptibility to emamectin benzoate, spinetoram, lambda-cyhalothrin, abamectin, and sophocarpidine. The median lethal doses (LC50) of lambda-cyhalothrin and imidacloprid to T. drosophilae adults were 60.41 mg/L and 100.58 mg/L, higher than the toxicities of the other six insecticides. Applying chlorantraniliprole, emamectin benzoate, sophocarpidine, abamectin, azadirachtin, and spinetoram resulted in low toxicity to D. suzukii pupae. However, the exposure of D. suzukii pupae or larvae to these insecticides at semilethal and sublethal doses decreased the parasitism or eclosion rate of T. drosophilae. These results improve our understanding of the effects of insecticide residues on T. drosophilae development and provide a basis for the combined use of chemical and biological options for managing D. suzukii. [ABSTRACT FROM AUTHOR]

NADPH-cytochrome P450 reductase (CPR) is crucial for the detoxification process catalysed by cytochrome P450, which targets various exogenous xenobiotics, as well as pesticides. In our research, we successfully obtained the complete cDNA sequence of Apolygus lucorum 's CPR (AlCPR) using reverse transcription PCR along with rapid amplification of cDNA ends technology. Bioinformatics analysis exhibited that the inferred amino acid sequence of AlCPR is characteristic of standard CPRs, featuring an N-terminal membrane anchor and three conserved FMN, FAD and NADP binding sites. Phylogenetic result revealed that AlCPR was positioned within the Hemiptera cluster, showing a close evolutionary relationship with the CPR of Cimex lectularius. The real-time quantitative PCR results demonstrated widespread expression of AlCPR across various life stages and tissues of A. lucorum , with the most prominent expression in adults and the abdominal region. Injecting double-stranded RNA of AlCPR only significantly increased the lambda-cyhalothrin susceptibility in lambda-cyhalothrin-resistant strain rather than the susceptible strain. These findings suggest a potential link between AlCPR and the P450-dependent defence mechanism against lambda-cyhalothrin in A. lucorum. [ABSTRACT FROM AUTHOR]

Strawberry is frequently attacked by mites, which directly affects the yield and quality of this fruit species. The WRKY Group III transcription factors (TFs) play an important role in plant tolerance to biotic sources of stress, such as pathogens and insect pests. In this study, six Group III WRKY TFs (FaWRKY25, FaWRKY31, FaWRKY32, FaWRKY43, FaWRKY44, and FaWRKY45) were identified in strawberry. A phylogenetic analysis showed that the six WRKY III TFs were divided into two clades and all had a conserved WRKYGQK domain and the C-X7-C-X23-H-T-C zinc finger motif. An interaction network analysis revealed that FaWRKY44 was co-expressing with FaWRKY25 and FaWRKY45. The expression patterns showed that the WRKY Group III genes responded to plant hormones and mite infestation in strawberry. To further verify the role of FaWRKY25 in plant resistance to mites, we cloned the FaWRKY25 gene and overexpressed it in transgenic plants. An in vivo subcellular localization analysis indicated that the FaWRKY25 protein was localized in the nucleus. Fewer mites were also detected on the wild-type plants than on FaWRKY25-overexpressing transgenic plants, suggesting that FaWRKY25 negatively regulates the resistance of strawberry to mites. The present study advances our understanding on a potential target that mites use to manipulate host plant defenses. [ABSTRACT FROM AUTHOR]

A fractured instrument (FI) in the root canal is a common complication during root canal therapy. Under current medical conditions, instrument separation cannot be completely avoided because of the complex morphology of root canals and the limited surgical field and operating space of the surgeon. FIs, especially those broken in the apical third of the canal, render it difficult to completely remove infection in the root canal, where the residual infection can easily develop into reinfection. The removal of FIs is therefore the preferred option for the majority of clinicians in such cases. However, root canal preparation instruments are frequently fractured during treatment because of the complex root canal morphology, such as curvature or severe calcification, which further increases the difficulty of instrument removal. In the present case, a 41-year-old female patient complained of worsening pain in the left maxillary first molar for 3 days. This patient had been treated at another hospital 2 years earlier, but the discomfort persisted after treatment. Preoperative periapical radiography revealed suspected FIs at the apical third of the mesiobuccal (MB) root and the middle third of the distal buccal (DB) root, underfilling of the palatal (P) root canal and large hypodense areas surrounding the periapical region of all roots. Next, the micro-ultrasound technique was used to remove the FI in the DB canal; a bypass through the second MB canal (MB2) was created to fill the apical stop of the MB root and the P canal was retreated. The therapeutic effect of the bypass technique was assessed by comparing bypass treatment and removal treatment for endodontic FIs. The 9-month and 27-month follow-ups revealed that the periapical inflammation surrounding the DB root treated after removal of the FI and the MB root treated by bypass was significantly controlled compared with that before the operation. In addition, the present report reviewed the research progress in bypass and removal techniques, focusing on the difficulties and key points of successful root canal therapy. [ABSTRACT FROM AUTHOR]

For industrial roller or bush chains, the bush swings relative to the pin at working condition. If proper lubrication is maintained, an elastohydrodynamic lubrication contact is formed between the pin and the bush. In this study, a custom-made pin was used to replace the steel ball of a ball-disk test rig and optical interferometric experiments were carried out to study the effect of pin generatrix on the lubrication performance. The effects of generatrix shape, stroke length and oil supply condition on the lubrication state were explored. It is found that the change of the generatrix has an important influence on the oil film thickness, especially under rare oil supply condition. [ABSTRACT FROM AUTHOR]