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Understanding the genetic basis of adaptive evolution following habitat expansion can have important implications for pest management. The pink rice borer (PRB), Sesamia inferens (Walker), is a destructive pest of rice that was historically restricted to regions south of 34° N latitude in China. However, with changes in global climate and farming practices, the distribution of this moth has progressively expanded, encompassing most regions in North China. Here, 3 highly differentiated subpopulations were discovered using high‐quality single‐nucleotide polymorphism and structural variant datasets across China, corresponding to northern, southern China regions, and the Yunnan‐Guizhou Plateau, with significant patterns of isolation by geographic and environmental distances. Our estimates of evolutionary history indicate asymmetric migration with varying population sizes across the 3 subpopulations. Selective sweep analyses estimated strong selection at insect cuticle glycine‐rich cuticular protein genes which are associated with enhanced desiccation adaptability in the northern group, and at the histone‐lysine‐N‐methyltransferase gene associated with range expansion and local adaptation in the Shandong population. Our findings have significant implications for the development of effective strategies to control this pest. [ABSTRACT FROM AUTHOR]

We attempt to determine the effect of the dietary switch from a native to non‐native prey on the gut microbiota in the predaceous ladybird Harmonia axyridis larvae and adults and examine how the dietary effect may vary across generations. We fed H. axyridis with different diets, native aphid Megoura japonica (Matsumura) versus non‐native mealybug Phenacoccus solenopsis (Tinsley), for 5 generations and sequenced microbes in the gut of the 3rd instar larvae and adults of the 1st, 3rd, and 5th generations. In addition, we identified microbes in M. japonica and P. solenopsis. The 2 prey species differed in microbial community as measured by abundances of prevalent microbial genera and diversity. In H. axyridis, abundances of some prevalent microbial genera differed between the 2 diets in the 1st and 3rd generations, but the difference disappeared in the 5th generation; this tendency is more obvious in adults than in larvae. Overall, gut microbial assemblages became gradually cohesive over generations. Microbial diversity differed between diets in the 1st and 3rd generations but became similar in the 5th generation. Major prevalent gut microbial genera are predicted to be associated with metabolic functions of H. axyridis and associated genera are more abundant for consuming the mealybug than the aphid. Our findings from this study suggest that the gut microbiota in H. axyridis is flexible in response to the dietary switch, but tends toward homogeneity in microbial composition over generations. [ABSTRACT FROM AUTHOR]

A fundamental understanding of the underlying mechanisms involved in biological invasions is crucial to developing effective risk assessment and control measures against invasive species. The fall armyworm (FAW), Spodoptera frugiperda, is a highly invasive pest that has rapidly spread from its native Americas into much of the Eastern Hemisphere, with a highly homogeneous nuclear genetic background. However, the exact mechanism behind its rapid introduction and propagation remains unclear. Here, a systematic investigation is conducted into the population dynamics of FAW in China from 2019 to 2021 and found that FAW individuals carrying "rice" mitochondria (FAW‐mR) are more prevalent (>98%) than that with "corn" mitochondria (FAW‐mC) at the initial stage of the invasion and in newly‐occupied non‐overwintering areas. Further fitness experiments show that the two hybrid‐strains of FAW exhibit different adaptions in the new environment in China, and this may have been facilitated by amino acid changes in mitochondrial‐encoded proteins. FAW‐mR used increases energy metabolism, faster wing‐beat frequencies, and lower wing loadings to drive greater flight performance and subsequent rapid colonization of new habitats. In contrast, FAW‐mC individuals adapt with more relaxed mitochondria and shuttle energetics into maternal investment, observed as faster development rate and higher fecundity. The presence of two different mitochondria types within FAW has the potential to significantly expand the range of damage and enhance competitive advantage. Overall, the study describes a novel invasion mechanism displayed by the FAW population that facilitates its expansion and establishment in new environments. [ABSTRACT FROM AUTHOR]

We made separate experiments to examine life‐history traits and activities of protective enzymes as affected by carbon dioxide (CO2) elevation to 780 μL/L as compared to 390 μL/L in imidacloprid‐ or buprofezin‐resistant strains of the brown planthopper (BPH) Nilaparvata lugens. We found an interaction effect between resistance and the CO2 level on the nymphal survival and duration in both resistant strains. Nymphal durations in both resistant strains were much shorter in the resistant than susceptible BPH at 780 μL/L but similar between them or slightly shorter in the resistant than susceptible BPH at 390 μL/L. Nymphal survival was lower for imidacloprid‐resistant than its susceptible BPH at 390 μL/L but higher at 780 μL/L; it stayed unaffected by the CO2 elevation in buprofezin‐resistant BPH. We did not observe an interaction effect between resistance and the CO2 level on major reproductive parameters in both resistant strains. But the 2 strains were not consistent across CO2 levels in all parameters. Our measurements of protective enzyme activities of superoxide dismutase, catalase, and peroxidase showed an interaction between resistance and the CO2 level. Overall, these enzymes became similar in activity between resistant and susceptible BPH at 780 μL/L compared to 390 μL/L and the change was more distinct in the imidacloprid‐ than buprofezin‐resistant BPH strains. Our findings suggest that CO2 elevation can affect life‐history traits of insecticide‐resistant BPH, while the effect may vary depending on the kind of insecticides it is resistant to. [ABSTRACT FROM AUTHOR]

Inherited bacterial symbionts are very common in arthropods, but infection frequency can vary widely among populations. Experiments and interpopulation comparisons suggest that host genetic background might be important in explaining this variation. Our extensive field investigation showed that the infection pattern of the facultative symbiont Cardinium was heterogeneous across geographical populations of the invasive whitefly Bemisia tabaci Mediterranean (MED) in China, with genetic nuclear differences evident in 2 of the populations: 1 with a low infection rate (SD line) and 1 with a high infection rate (HaN line). However, whether the heterogeneous frequency of Cardinium is associated with the host genetic background remains poorly understood. Here, we compared the fitness of the Cardinium‐infected and uninfected sublines with similar nuclear genetic backgrounds from SD and HaN lines, respectively, and further determine whether host extranuclear or nuclear genotype influenced the Cardinium–host phenotype by performing 2 new introgression series of 6 generations between SD and HaN lines (i.e., Cardinium‐infected females of SD were backcrossed with uninfected males of HaN, and vice versa). The results showed that Cardinium provides marginal fitness benefits in the SD line, whereas Cardinium provides strong fitness benefits in the HaN line. Further, both Cardinium and the Cardinium–host nuclear interaction influence the fecundity and pre‐adult survival rate of B. tabaci, whereas the extranuclear genotype does not. In conclusion, our results provide evidence that Cardinium‐mediated fitness effects were closely associated with the host genetic background, which provides a fundamental basis for understanding the mechanism underlying the heterogeneous distribution of Cardinium in B. tabaci MED populations across China. [ABSTRACT FROM AUTHOR]

BACKGROUND: The gut microbiota has an intimate relationship with insect hosts and this relationship can become complicated with parasitic organisms being involved with the host. To date there has been limited evidence for the relevance of parasitism of the host by parasitoids to host gut microbiota, especially in host insect predators. Here, our study examined gut microbiotas in larvae of the predaceous lady beetle, Coccinella septempunctata, in response to their parasitism by Homalotylus eytelweinii regarding the development progress of offspring parasitoids. RESULTS: Overall 58.5% of gut bacterial operational taxonomic units (OTUs) in the parasitized lady beetle were different from those in the unparasitized host. The phylum Proteobacteria abundance increased while Firmicutes decreased in parasitized hosts compared to the unparasitized. The abundance of genus Aeribacillus decreased substantially in the parasitized lady beetle across all stages of the offspring development compared to the unparasitized host. The α‐diversity of the gut microbiota in a parasitized lady beetle larva increased at the early stage of offspring parasitoids and then returned over the intermediate and later stages. Analyses of β‐diversity indicated that the gut microbial community in a parasitized lady beetle was distinct from that in an unparasitized one and different between early or middle and late stages of offspring parasitoids in parasitized hosts. CONCLUSION: Our results provide evidence for the relevance of the gut microbiota to interactions between a lady beetle host and its parasitoid. Our study provides a starting point for further investigations of the role the gut microbiota may play in host‐parasitoid interactions. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Aim: The sweet potato whitefly, Bemisia tabaci MED is a globally invasive species that causes serious economic damage to agroecosystems. Despite the significant threat it poses to agricultural and economic crops worldwide, the global perspective of the invasion patterns and genetic mechanisms contributing to the success of this notorious pest is still poorly understood. The objective of this research was to enhance genome and population genetic analyses to better understand the intricate invasion patterns of B. tabaci MED. Location: Samples were collected in native (Spain, Croatia, Bosnia and Herzegovina, Cyprus, and Israel) and invaded regions (China, South Korea and North America). Methods: We first assembled a chromosome‐scale reference genome of B. tabaci MED and then employed the restriction site‐associated 2b‐RAD method to genotype over 20,000 high‐quality single‐nucleotide polymorphisms from 29 geographical populations. Results: A reference genome of B. tabaci MED, with a size of 637.47 Mb, was available. The majority of the assembled sequences (99%) were anchored onto 10 linkage groups, with an N50 size of 58.76 Mb, representing a significant improvement over previous whitefly genome assemblies. We identified rapidly expanded gene families and positively selected genes, probably contributing to successful invasion and rapid adaptation to the new environment. Population genomics analysis showed that three highly differentiated genetic groups were formed, and complex and extensive gene flow occurred across the Mediterranean populations. The genetic admixture patterns in East Asia populations were distinct from those in North America, indicating that they had different source populations. Conclusions: The high‐quality, chromosome‐scale genome of B. tabaci MED offered opportunities for more comprehensive genome‐wide studies and provided solid foundation to the complex introduction events and the differential invasiveness of B. tabaci MED worldwide. [ABSTRACT FROM AUTHOR]

This paper focus on the detection for false data injection (FDI) attacks. Under external conditions, the state and the output variables of Nonlinear Cyber‐Physical Systems (NCPSs) cannot be described by a linear relationship. It is difficult to detect the attacked systems. The Laguerre function model has excellent approximation capability to change structural parameters such as system delay and order, making it convenient for online parameter identification and suitable for complex industrial process control. Accordingly, in order to detect FDI attacks for NCPSs, the Laguerre function is adopted to detect FDI attacks and improve the detection rate. Numerical simulations verify the effectiveness of this method. [ABSTRACT FROM AUTHOR]

As a biocontrol agent of aphids and coccids, the harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), was introduced from its native Asian range into North America. There, it has spread quickly and widely, potentially contributing to the decline of endemic ladybirds. This study examined microbial communities residing in H. axyridis in its native and introduced or invaded regions. We collected ladybirds at 11 localities across mainland China (native range) and at seven localities across the USA (invaded range) and applied next‐generation amplicon sequencing to examine microbial communities. We found that the diversity of the microbial community of H. axyridis in the invaded range declined compared to the native range. The microbial community differed markedly in composition between native and invaded ranges. Among all identified 22047 amplicon sequence variants, only 4.2% were shared by the two ranges, whereas 4967 were unique to the invaded and 16159 to the native range. Our findings suggest that the composition of the microbial community of H. axyridis is largely restructured in the invaded North American region compared to the native Asian region. [ABSTRACT FROM AUTHOR]

Although iris recognition verification is considered to be the safest method of biometric verification, studies have shown that iris features may be illegally used. To protect iris features and further improve the security of iris recognition and verification, this study applies the Gaussian and Laplacian mechanisms and to hide iris features by differentiating privacy. The efficiency of the algorithm and evaluation of the image quality by the image hashing algorithm are selected as indicators to evaluate these mechanisms. The experimental results indicate that the security of an iris image can be significantly improved using differential privacy protection. [ABSTRACT FROM AUTHOR]

Model-free predictive control is a data-driven control method that directly computes the control input from massive input/output datasets. It does not require the mathematical models that are used in conventional model predictive control. It has recently been shown that the control offered by model-free predictive control can be improved by the introduction of polynomial regression vectors containing the control input and measurement output. In this paper, we extend these findings to multi-input multi-output nonlinear systems and investigate the effectiveness of the approach through numerical simulations of a wastewater treatment process. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]