Successful Eradication of the Asian Longhorn Beetle, Anoplophora glabripennis, from North-Eastern Italy: Protocol, Techniques and Results

Anoplophora glabripennis, an invasive longhorned beetle, has the potential to damage fruit trees in Japan

Invasive Anoplophora glabripennis recently became established in Japan and has caused heavy damage to several street-tree species. Overseas, A. glabripennis infests trees of the genera Acer and Populus as common host plants, and Malus, Pyrus, and Prunus (Rosaceae), including apple, pear, and plum trees; it therefore poses a potential risk to the production of economically valuable fruits in Japan. Fruit farms in areas already invaded by A. glabripennis are now threatened with tree infestation. We aimed to determine the potential damage to major fruit species in Japan. In the laboratory, we determined if the adult beetle is attracted to the odor of each of these tree species' branches; two confirmed host plant species and five Rosaceae fruit species, as well as its feeding preferences among branches of one host plant and the five fruit trees and its oviposition preferences among them. Among the fruit species, cherry branch had the highest rate of odor orientation by males. The feeding-preference assay showed that, besides the host plant, Japanese pear was the most consumed among the fruit trees. The potential risk of A. glabripennis laying eggs on fruit-tree branches was high for Japanese pear and above zero for plum, apple, and cherry branches.

High Trunk Truncation as a Potential Sustainable Management Option for Asian Longhorned Beetle on Salix babylonica

The Asian longhorned beetle (ALB) causes substantial economic and ecological losses, thus, an environmentally friendly management strategy is needed. Here, we propose high trunk truncation (HTT), the removal of the above 200 cm portion of trees, as a sustainable management strategy to control ALB. To examine the hypothesis, an initial step involved the assessment of various biological characteristics of ALB. Subsequently, a controlled field experiment was carried out utilizing HTT. Finally, HTT was applied in two additional ALB infestation regions. The results of the study of the biological characteristics of ALB showed that 76.31-78.88% of frass holes and 85.08-87.93% of emergence holes were located on branches above 200 cm. Adults preferred to feed on branches 2-3 cm in diameter, ALB eggs were predominantly laid on 5 cm branches, and both were primarily located above 200 cm. These results revealed a correlation between the number of ALBs and the tree crown height. The controlled field experiment showed that the number of ALBs was significantly decreased when the HTT strategy was implemented: approximately 90% of frass holes and 95% of adults were eradicated by HTT compared with the control. Different field surveys involving HTT have shown similar results. These findings provide valuable insights into a sustainable and efficient management strategy for reducing the number of ALBs.

Research on Photoinduction-Based Technology for Trapping Asian Longhorned Beetle (Anoplophora glabripennis (Motschulsky, 1853) (Coleoptera: Cerambycidae)

Light traps play a crucial role in monitoring pest populations. However, the phototactic behavior of adult Asian longhorned beetle (ALB) remains enigmatic. To provide a theoretical foundation to select the suitable light emitting diode (LED)-based light sources used for monitoring ALB, we compared the effect of exposure time on the phototactic response rates of adults at wavelengths of 365 nm, 420 nm, 435 nm, and 515 nm, and found that the phototactic rate increased gradually when the exposure time was prolonged, but there was no significant difference between different exposure times. We evaluated the effect of diel rhythm and found the highest phototactic rate at night (0:00-2:00) under 420 nm and 435 nm illumination (74-82%). Finally, we determined the phototactic behavioral response of adults to 14 different wavelengths and found both females and males showed a preference for violet wavelengths (420 nm and 435 nm). Furthermore, the effect of the light intensity experiments showed that there were no significant differences in the trapping rate between different light intensities at 120 min exposure time. Our findings demonstrate that ALB is a positively phototactic insect, showing that 420 nm and 435 nm are the most suitable wavelengths for attracting adults.

Predicting Distribution of the Asian Longhorned Beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae) and Its Natural Enemies in China

Simple Summary

The Asian longhorned beetle, Anoplophora glabripennis, is a worldwide invasive creature that has invaded the world for more than 20 years. Although previous studies have predicted the distribution range of A. glabripennis, this single species distribution prediction cannot provide more potential management strategies for the control of invasive organisms. In this study, we incorporated two important natural enemies (D. helophoroides and D. major) of A. glabripennis into the prediction model. We found that climate change led to the northward migration of the suitable areas of A. glabripennis and its natural enemies. In China, only the occurrence regions of A. glabripennis are mainly distributed in parts of Xinjiang, Xizang, and Qinghai. In other occurrence regions of A. glabripennis, control models of A. glabripennis + D. helophoroides, A. glabripennis + D. major, or A. glabripennis + D. helophoroides + D. major were found. Fortunately, part of the areas in Xinjiang, Xizang, and Qinghai are potentially suitable for D. helophoroides and D. major under future climatic conditions. Therefore, these two natural enemies may be used in these regions to control A. glabripennis in the future.

Abstract

The Asian longhorned beetle, Anoplophora glabripennis, is a forestry pest found worldwide. A. glabripennis causes serious harm because of the lack of natural enemies in the invaded areas. Dastarcus helophoroides and Dendrocopos major are important natural enemies of A. glabripennis. MaxEnt was used to simulate the distribution of D. helophoroides and D. major in China, and their suitable areas were superimposed to pinpoint which regions are potentially appropriate to release or establish natural enemy populations under current and future conditions. The results showed that, with climate change, the suitable areas of D. helophoroides and D. major migrated northward; the centroid shift of A. glabripennis was greater than those of D. helophoroides and D. major. From current conditions to 2090, the suitable area of A. glabripennis, D. helophoroides, and D. major will increase by 1.44 × 10⁴, 20.10 × 10⁴, and 31.64 × 10⁴ km², respectively. Northern China (e.g., Xinjiang, Gansu, and Inner Mongolia), where A. glabripennis causes more serious damage, is also a potentially suitable area for D. helophoroides and D. major, and this provides a potential strategy for the management of A. glabripennis. Therefore, we suggest that natural enemies should be included in the model used for predicting suitable areas for invasive pests.