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The Asian longhorn beetle (ALB) Anoplophora glabripennis is one of the most successful and most feared invasive insect species worldwide. This review covers recent research concerning the distribution of and damage caused by ALB, as well as major efforts to control and manage ALB in China. The distribution and destruction range of ALB have continued to expand over the past decade worldwide, and the number of interceptions has remained high. Detection and monitoring methods for the early discovery of ALB have diversified, with advances in semiochemical research and using satellite remote sensing in China. Ecological control of ALB in China involves planting mixtures of preferred and resistant tree species, and this practice can prevent outbreaks. In addition, strategies for chemical and biological control of ALB have achieved promising results during the last decade in China, especially the development of insecticides targeting different stages of ALB, and applying Dastarcus helophoroides and Dendrocopos major as biocontrol agents. Finally, we analyze recommendations for ALB prevention and management strategies based on native range and invasive area research. This information will hopefully help some invaded areas where the target is containment of ALB. [ABSTRACT FROM AUTHOR]

BACKGROUND: Monochamus carolinensis is an important vector of pinewood nematodes in North America that is under quarantine in several countries worldwide. The distribution of M. carolinensis was previously thought to be limited to North America; however, we discovered it during trapping in China in 2022. Using this discovery and information regarding the area of origin, we applied a machine‐learning algorithm based on the maximum entropy principle to predict the current and future (2050s, 2070s) potential distribution areas of M. carolinensis using bioclimatic variables. RESULTS: The biological suitability of M. carolinensis was mainly driven by precipitation factors (BIO18, BIO15, BIO19), with 87.18% of the potential distribution areas located in South America, Asia, North America and Africa. Future potential distribution areas of M. carolinensis are predicted to expand to high latitudes, with an average increase of 10 245 874.88 km2, and only 6.89% of the current suitable areas will become unsuitable. The potential distribution areas in 2070 are largest under the SSP585 scenario, with a 41.40% predicted increase (52 309 803.61 km2) above the current distribution, mainly reflecting an increase of the marginally and highly suitable areas. CONCLUSION: The determination of dominant climatic factors and potential distribution areas will help provide an early warning for an M. carolinensis invasion, as well as provide a scientific basis for the spread and outbreak, facilitating development of effective governmental prevention and control measures. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The acoustic detection model of activity signals based on deep learning could detect wood‐boring pests accurately and reliably. However, the black‐box characteristics of the deep learning model have limited the credibility of the results and hindered its application. Aiming to address the reliability and interpretability of the model, this paper designed an active interpretable model called Dynamic Acoustic Larvae Prototype Network (DalPNet), which used the prototype to assist model decisions and achieve more flexible model explanation through dynamic feature patch computation. Results: In the experiments, the average recognition accuracy of the DalPNet on the simple test set and anti‐noise test set for Semanotus bifasciatus larval activity signals reached 99.3% and 98.5%, respectively. The quantitative evaluation of interpretability was measured by the relative area under the curve (RAUC) and the cumulative slope (CS) of the accuracy change curve in this paper. In the experiments, the RAUC and the CS of DalPNet were 0.2923 and −2.0105, respectively. Additionally, according to the visualization results, the explanation results of DalPNet were more accurate in locating the bite pulses of the larvae and could better focus on multiple bite pulses in one signal, which showed better performance compared to the baseline model. Conclusion: The experimental results demonstrated that the proposed DalPNet had better explanation while ensuring recognition accuracy. In view of that, it could improve the trust of forestry custodians in the activity signals detection model and aid in the practical application of the model in the forestry field. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pine wilt disease (PWD) outbreaks have affected extensive areas of South China's forests, but the factors explaining landscape patterns of pine mortality are poorly understood. The objective of this study was to determine the relative importance of stand structure, topography, landscape context, and beetle pressure in explaining PWD severity. During 2020–2021, we identified 66 plots based on mapped PWD infestation severity. We built PWD infestation maps for 2019–2021 through field surveys. Stand structure and topography were obtained from Forest Resources Management 'One Map' and elevation raster data. We then used 'One Map' and PWD infestation maps to determine landscape context and beetle pressure variables at different spatial scales. The relative importance of 12 explanatory variables was analyzed using multi‐model inference. RESULTS: In this study, we show that: (i) 1 km was the best spatial scale related to pine mortality, and (ii) models including landscape context and beetle pressure were much better at predicting pine mortality than models using only stand‐level variables. CONCLUSION: Landscape‐level variables, particularly beetle pressure, were the most consistent predictors of subsequent pine mortality within susceptible stands. These results may help forest managers identify locations vulnerable to PWD and improve existing strategies for outbreak control. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Semanotus bifasciatus Motschulsky (Coleoptera: Cerambycidae) is one of the most destructive wood‐boring pests of Platycladus trees in East Asia, threatening the protection of antique cypresses and urban ecological safety. Early identification of Semanotus bifasciatus attacks can help forest managers mitigate the infestation before it turns into an outbreak. Acoustic detection technology is a non‐destructive and continuous monitoring method with the potential to early identify and accurately evaluate the wood‐boring damage. However, few studies have focused on the detection timing and corresponding acoustic features. In this study, we employed a manipulated insect infestation experiment to identify time windows in which early instar Semanotus bifasciatus larvae are most actively boring and feeding within logs and to identify acoustic features that distinguish larval sounds from typical background noise. RESULTS: The Semanotus bifasciatus larvae produced sounds most frequently between 13:00 and 20:00 while sounds were detectable from the first to the third instar during the larval growth stage, indicating a suitable time window for early detection. The stepwise regression (SR) model was optimal for detecting the larval instar [coefficient of determination (R2) = 0.71, root mean squared error of prediction (RMSEp) = 0.42, and relative percent deviation (RPD) = 3.38] while the best model for predicting larval population size was the partial least squares regression (PLSR) model (R2 = 0.97, RMSEp = 61.96, and RPD = 28.87). CONCLUSION: This study developed an acoustic method for identifying the early attack of Semanotus bifasciatus (including detection time window, feature variables and models for larval instar prediction and population size estimation). This technology integrated with internet of things (IoT) framework can be of value in developing an automated monitoring system for forest wood borer, and provide necessary guidance for integrated pest management (IPM). © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Eogystia hippophaecolus (Hua et al.) is an important boring pest that primarily damages sea buckthorn, causing large ecological and economic damages in China. In this study, we used scanning electron microscopy to investigate the sensilla on six olfactory tissues of male E. hippophaecolus: antennae, labial palps, external genitals, propodeum, mesopodium, and metapedes. On the antennae, two types of sensillum trichodea, two types of sensillum basiconica, a type of sensillum coeloconica, and Böhm's bristles were found. The labial palps had sensilla trichodea and chaetica. On the external genitals, three types of sensilla trichodea were the only sensilla. Böhm bristles were found on the base of the tibia and at the terminus of the tarsus. Most sensilla were distributed on the tarsus of the three pairs of legs, and notably, a majority of which were sensilla trichodea and sensilla chaetica, were on the pretarsus and telotarsus of the three pairs of legs. In this study, the distribution, number, type, and morphology of the sensilla on six olfactory organs of E. hippophaecolus were determined, which established the foundation for a future immunohistochemical search of olfactory proteins. Research highlights: Eogystia hippophaecolus is a serious pest of seabuckthorn. The distribution, number, type, and morphology of olfactory sensilla of E. hippophaecolus are determined. The function and distribution of sensilla are compared with those of other insects. [ABSTRACT FROM AUTHOR]

Pine wilt disease ( PWD) is considered as the most destructive forest-invasive alien species in China. We measured gas exchange parameters and foliar carbon isotope ratios (δ13C) of different infection phases of Masson pine in order to investigate the effect of Bursaphelenchus xylophilus infection on photosynthetic responses and resource-use efficiency. The results showed that net photosynthetic rate ( Pn), transpiration rate ( T), stomatal conductance ( gs), and internal CO2 concentrations ( Ci) decreased in the infested trees at photosynthetic photon flux density ( PPFD) levels from 0 to 2,000 μmol m−2 s−1 compared with controls. The maximum net photosynthetic rate ( Pmax) was significantly declined in the infected trees than in controls ( p < .05). There also exist significant differences in dark respiration rate ( Rd) among different infection phases ( p < .05), but the value is highest in the middle infection phase, followed by the control and then the terminal infection phase. This indicates that Pinus massoniana plants need to consume more photosynthetic products during the middle infection phase in order to defend against pine sawyer beetle feeding and PWD infection. Isotopic analysis revealed a significant decrease of the foliar δ13C ( p < .05), as much as 2.5‰ lower in the infected trees. The mean leaf N content was about 12.94% less in the middle infection phase and 27.06% less in the terminal infection phase, causing a significant increase of the foliar C:N ratio in infested trees. Both of the net photosynthetic rates and foliar δ13C were linearly correlated with the foliar N content. We also found a significant decrease ( p < .05) of resource-use efficiency in PWD-induced P. massoniana plants, which can be attributed to the closure of stomatal pores and the inactivation or loss of both Rubisco and other key Calvin cycle enzymes. This study highlights the impact of photosynthetic characteristics, foliar carbon isotope ratios, and resource-use efficiency of PWD-induced trees, which can help identify PWD infestations at the photosynthetic and physiological levels so as to better facilitate management actions. [ABSTRACT FROM AUTHOR]

The cytochrome P450 enzymes encoded by the Halloween genes - spook ( spo), phantom ( phm), disembodied ( dib), shadow ( sad), and shade ( shd) - catalyze a series of hydroxylation steps resulting in the active molting hormone 20-hydroxyecdysone (20E). This study investigated 20E and ecdysone titers and the expression profile of Halloween genes and ecdysone receptor ( EcR) during larval, pupal, and adult stages in seabuckthorn carpenterworm, Holcocerus hippophaecolus Hua ( Lepidoptera: Cossidae). Hh-spo, Hh-phm, Hh-dib, and Hh-sad showed predominant expression in the prothoracic gland at the larval stage, whereas Hh-shd and Hh-EcR were significantly expressed in the fat body. The mRNA levels of Hh-spo, Hh-phm, Hh-dib, Hh-shd, Hh-sad, and Hh-EcR were lowest from late October to middle April, when the insects were in overwintering dormancy, but began to increase from May each year, when the insects were terminating quiescence. Concomitant with the changes in these genes, 20E and ecdysone titers gradually increased during the 4-year life cycle of H. hippophaecolus. These data indicate that the seasonal expressions of Hh-spo, Hh-phm, Hh-shd, and Hh-EcR play crucial roles in quiescence of the overwintering period, and are responsible for the long larval phase and the exact timing and amplitude of the ecdysteroid titer required for the coordination of growth and development in H. hippophaecolus. [ABSTRACT FROM AUTHOR]

Pine wilt disease ( PWD) has caused significant Masson pine mortality in the Three Gorges reservoir region in central China. In this study, five uniform Masson pine stand types infected by PWD were selected and surveyed on slopes and aspects with similar environmental conditions. In sites that had been infected, soil bulk density was reduced, and the difference among the groups was statistically significant ( P < 0.05) at the 0-10 cm and 10-20 cm soil layers, but not at 20-40 cm. Other soil water-related physical properties, excluding noncapillary porosity, significantly differed among the groups in all soil layers. Additionally, the values of available phosphorus, sodium, potassium, calcium, and magnesium were higher in the invaded stands, but the total nitrogen and organic matter contents were lower. Masson pine does not become reestablished following PWD-induced mortality but is instead replaced by broad-leaved tree species. Among the 19 examined environmental variables, five were found to be significantly related with the ordination of plant community structure: Masson pine stumps ( MPS), K+, capillary water holding capacity ( CWHC), capillary porosity ( CP), and soil water content ( SWC). Among these factors, the plant community structure was principally related to MPS and K+. The findings of this study show that the outbreak of PWD has impacted Masson pine forest soil properties and altered forest community composition. The disease is negatively related with the presence of Masson pine and positively associated with that of broad-leaved tree species. [ABSTRACT FROM AUTHOR]