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To improve safety during ordinary railway catenary maintenance operations and the anti-interference of transmission information, a set of ordinary railway catenary condition monitoring system based on artificial intelligence robot technology and LoRa communication technology is designed. The system is mainly composed of a robot that can inspect electricity, hook ground wire and return line in the job site as a data acquisition device and the pattern constitution of transmitting and processing status information outside the job site and realizing visualized monitoring at the terminal. After the monitoring and simulation test, the anti-interference results of the robot data collection are in line with expectations. Meanwhile, the data transmission between the LoRa gateway and the cloud server is normal, and visualized monitoring of the status information from the PC side is realized.

The vegetative insecticidal protein Vip3Aa from Bacillus thuringiensis (Bt) has been produced by transgenic crops to counter pest resistance to the widely used crystalline (Cry) insecticidal proteins from Bt. To proactively manage pest resistance, there is an urgent need to better understand the genetic basis of resistance to Vip3Aa, which has been largely unknown. We discovered that retrotransposon-mediated alternative splicing of a midgut-specific chitin synthase gene was associated with 5,560-fold resistance to Vip3Aa in a laboratory-selected strain of the fall armyworm, a globally important crop pest. The same mutation in this gene was also detected in a field population. Knockout of this gene via CRISPR/Cas9 caused high levels of resistance to Vip3Aa in fall armyworm and 2 other lepidopteran pests. The insights provided by these results could help to advance monitoring and management of pest resistance to Vip3Aa. The insecticidal protein Vip3Aa is used in genetically engineered crops to overcome pest resistance to other insecticidal transgenes. This study shows that insertion of a transposable element into a gut-specific chitin synthase gene causes Vip3Aa resistance in field-collected individuals of the lepidopteran pest Spodoptera frugiperda (fall armyworm). [ABSTRACT FROM AUTHOR]

The sex of Lepidoptera species can typically be identified at the pupal or adult stage by their morphological characteristics. However, for most species, no obvious sex‐specific traits can be used at the larval or embryonic stage. The growing interest in studying sex determination and differentiation, along with the potential application of research findings in genetic regulation techniques, is promoting the advancement of new sexing methods at early developmental stages. In this study, the sex of individual eggs and larvae was successfully identified by means of W chromosome molecular markers, which were identified through analysing the previously published W chromosome sequence data of Spodoptera frugiperda (Lepidoptera: Noctuidae). Additionally, we present methods to extract DNA and RNA from individual eggs and larval hemolymph. These techniques provide a simple and dependable method to identify sex at pre‐pupal stages. This approach could potentially be extended to other Lepidoptera species of which the W chromosome information is available. [ABSTRACT FROM AUTHOR]

The major plant pest fall armyworm (FAW), Spodoptera frugiperda, is native to the Americas and has colonized Africa and Asia within the Eastern hemisphere since 2016, causing severe damage to multiple agricultural crop species. However, the genetic origin of these invasive populations requires more in‐depth exploration. We analysed genetic variation across the genomes of 280 FAW individuals from both the Eastern hemisphere and the Americas. The global range‐wide genetic structure of FAW shows that the FAW in America has experienced deep differentiation, largely consistent with the Z‐chromosomal Tpi haplotypes commonly used to differentiate 'corn‐strain' and 'rice‐strain' populations. The invasive populations from Africa and Asia are different from the American ones and have a relatively homogeneous population structure, consistent with the common origin and recent spreading from Africa to Asia. Our analyses suggest that north‐ and central American 'corn‐strain' FAW are the most likely sources of the invasion into the Eastern hemisphere. Furthermore, evidence based on genomic, transcriptomic and mitochondrial haplotype network analyses indicates an earlier, independent introduction of FAW into Africa, with subsequent migration into the recent invasive population. [ABSTRACT FROM AUTHOR]

Evolution of resistance to Cry proteins in multiple pest insects has been threatening the sustainable use of Bacillus thuringiensis (Bt)‐transgenic crops. Better understanding about the mechanism of resistance to Cry proteins in insects is needed. Our preliminary study reported that the transcription of HaABCC3 was significantly decreased in a near‐isogenic line (LFC2) of a Cry1Ac‐resistant strain (LF60) of the global pest Helicoverpa armigera. However, the causality between HaABCC3 downregulation and resistance to Cry1Ac remains to be verified, and the regulatory mechanism underlying the HaABCC3 downregulation is still unclear. In this study, our data showed that both HaABCC3 and HaABCC3 downregulation were genetically linked to resistance to Cry1Ac in LF60. However, no InDels were observed in the coding sequence of HaABCC3 from LF60. Furthermore, F1 offspring from the cross of LF60 and a HaABCC2/3‐knockout mutant exhibited moderate resistance to Cry1Ac toxin; this indicated that the high resistance to Cry1Ac toxin in LF60 may have resulted from multiple genetic factors, including HaABCC2 mis‐splicing and HaABCC3 downregulation. Results from luciferase reporter assays showed that promoter activity of HaABCC3 in LF60 was significantly lower than that in the susceptible strain, which indicated that HaABCC3 downregulation was likely mediated by promoter variation. Consistently, multiple variations of the GATA‐ or FoxA‐binding sites in the promoter region of HaABCC3 were identified. Collectively, all results in this study suggested that the downregulation of HaABCC3 observed in the H. armigera LF60 strain, which is resistant to Cry1Ac, may be mediated by a cis‐regulatory mechanism. [ABSTRACT FROM AUTHOR]

The lawn cutworm, Spodoptera depravata, is one of the most important pests that causes economic damage to grass crops. This study reports the complete mitochondrial genome of an S. depravata sample collected in China. The genome is a circular molecule 15,460 bp in length with an overall A + T content of 81.6%. It contains 13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes. The gene content and organization of the mitogenome of S. depravata are identical to those of other Spodoptera species. Maximum-likelihood phylogenetic analysis based on mitogenomes showed a close evolutionary relationship between S. depravata and S. exempta. This study provides new molecular data for the identification and further phylogenetic analyses of Spodoptera species. [ABSTRACT FROM AUTHOR]