Pest Of Trees Research Articles

Nutritional Potential and Low Heavy Metals Content of Oryctes monoceros (Olivier, 1789) and Rhynchophorus phoenicis (Fabricius, 1801) Adults, Two Coleopteran Species Consumed in Togo

Oryctes monoceros (Olivier, 1789) (Scarabaeidae) and Rhynchophorus phoenicis (Fabricius, 1801) (Curculionidae) are two insects generally known as formidable pests of oil palms and coconuts trees. Although little known, different developmental stages of these insects are consumed. The aim of this study is to determine the composition of these adult Coleopteran species in order to promote their consumption as a strategy for enhancing food security. Chemical analyses were carried out on adults of both species. Samples of O. monoceros and R. phoenicis were collected in three localities in Togo. The ash, protein, vitamin, and lipid contents were determined according to the AOAC reference methods. The fiber contents were obtained by the method of Weende. The minerals and heavy metals were analyzed by atomic absorption spectrophotometry and colorimetry. Fatty acid composition was determined by gas chromatography. The results showed the average protein content ranges from 44.32 ± 0.83 to 45.89 ± 0.83%. The lipid level is between 15.06 ± 0.28% and 14.64 ± 0.54. Their lipids contain unsaturated fatty acids, notably oleic (40.84 ± 0.112 vs. 40.84 ± 0.11%), linoleic (4.49 ± 0.00 vs. 5.07 ± 0.02%), and α-linolenic (5.07 ± 0.02 vs. 6.35 ± 0.01%) acid. They are excellent sources of minerals and vitamins. They are also free of heavy metals. These species could, therefore, contribute to the nutritional balance of consumers. They deserve to be better promoted for human consumption, as they could make a significant contribution to the fight against malnutrition and constitute a novel food source.

Interspecific Competition Between Eotetranychus sexmaculatus Riley and Oligonychus biharensis Hirst (Acari: Tetranychidae).

Eotetranychus sexmaculatus has long been recognized as an important spider mite pest of rubber trees. Recently, increasing damage from Oligonychus biharensis has elevated its importance as a key spider mite pest. These two species share highly overlapping ecological niches, with outbreaks strongly associated with high temperatures and drought stresses. However, little is known regarding the potential competition between these spider mite species and the role of temperature in shaping these interactions. This study investigates the development and reproduction of E. sexmaculatus and O. biharensis at varying population densities, and evaluates their dynamics at 27 °C, 30 °C, and 33 °C. Five initial population densities of E. sexmaculatus and O. biharensis were evaluated in mixed populations: 0:30, 10:20, 15:15, 20:10, and 30:0. The results demonstrate both intra- and interspecific competition between E. sexmaculatus and O. biharensis. At all three intraspecific densities, the survival rate and lifespan of both species declined as density increased, with fecundity also decreasing at higher densities. Single-species populations of each mite were larger in number when compared with mixed populations. Across all treatments, the mean and peak values of the intrinsic rate of increase (rm) were greater in O. biharensis than in E. sexmaculatus. Additionally, increasing temperatures accelerated the displacement of E. sexmaculatus by O. biharensis, regardless of the initial population density. When the mixed populations of E. sexmaculatus and O. biharensis were at densities of 10:20, the highest interspecific competition coefficients were obtained at 33 °C, with values of 0.6591. In conclusion, O. biharensis consistently outcompeted E. sexmaculatus at all tested temperatures, irrespective of initial densities, providing valuable insights into the competitive dynamics of dominant rubber tree pests.

Apnet: Lightweight network for apricot tree disease and pest detection in real-world complex backgrounds

Apricot trees, serving as critical agricultural resources, hold a significant role within the agricultural domain. Conventional methods for detecting pests and diseases in these trees are notably labor-intensive. Many conditions affecting apricot trees manifest distinct visual symptoms that are ideally suited for precise identification and classification via deep learning techniques. Despite this, the academic realm currently lacks extensive, realistic datasets and deep learning strategies specifically crafted for apricot trees. This study introduces ATZD01, a publicly accessible dataset encompassing 11 categories of apricot tree pests and diseases, meticulously compiled under genuine field conditions. Furthermore, we introduce an innovative detection algorithm founded on convolutional neural networks, specifically devised for the management of apricot tree pests and diseases. To enhance the accuracy of detection, we have developed a novel object detection framework, APNet, alongside a dedicated module, the Adaptive Thresholding Algorithm (ATA), tailored for the detection of apricot tree afflictions. Experimental evaluations reveal that our proposed algorithm attains an accuracy rate of 87.1% on ATZD01, surpassing the performance of all other leading algorithms tested, thereby affirming the effectiveness of our dataset and model. The code and dataset will be made available at https://github.com/meanlang/ATZD01.

Development and reproduction of Grapholita molesta (Lepidoptera: Tortricidae) on the 3 artificial diets in the laboratory.

Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is a major pest of many fruit trees. The large-scale artificial propagation technology of the insect is the basis for the field application of the sterile insect technique and biological control products based on host mass reproduction. However, a low-cost diet with easily accessible materials remains lacking. In this study, we assessed the insect rearing performance feeding on 3 artificial diets: D1: an artificial diet based on wheat bran and soybean powders; D2: an artificial diet based on soybean powder, maize powders, and tomato sauce; and D3: an artificial diet based on soybean powder, maize powder, tomato sauce, and wheat bran, with apples as a control, using 2-sex life table. At 26 ± 1 °C, 70 ± 5% humidity, and 16:8h L:D photoperiod, the biological indicators of G. molesta fed D1 were consistent with those fed apples, with a larval stage of 14.88 d, a pupal stage of 7.57 d, adult longevity of 22.69 d, egg deposition count of 223.22, intrinsic rate of increase (r) of 0.1359, finite rate of increase (λ) of 1.1456, and net reproductive rate (R0) of 94.50. D1 was used to continuously rear G. molesta population for 5 generations, all life parameters remained normal. These results indicated that the artificial diet based on wheat bran and soybean powder could be used for rearing of the insect. This study proposes an available and cost-effective artificial diet for G. molesta, facilitating the application of green prevention and control technology.

Telenomus dendrolimi (Matsumura) (Hymenoptera, Scelionidae) reared from the eggs of Dendrolimus houi (Lajonquiere) (Lepidoptera, Lasiocampidae) from China

The pine moth, Dendrolimus houi (Lajonquiere), is a notorious insect pest of coniferous trees in South China. A gregarious egg parasitoid in the family Scelionidae shows great potential to be mass-reared for the biological control of D. houi. This parasitoid is identified as Telenomus dendrolimi (Matsumura) based on comparison to paratype specimens of Telenomus dendrolimusi Chu, a junior synonym of T. dendrolimi. Telenomus dendrolimi is redescribed and included in a molecular analysis. In addition to parasitizing D. houi, T. dendrolimi was found to successfully parasitize six other species under laboratory conditions, with Antheraea pernyi (Guérin-Méneville) the most suitable host for mass-rearing.

DNA sequence data confirms the presence of two closely related cypress-feeding aphid species on African cypress (Widdringtonia spp.) in South Africa

Aphids in the genus Cinara (Hemiptera: Aphididae) are pests of coniferous trees globally. Some of these aphids have become invasive in various parts of the world and have led to significant economic and environmental damage. During surveys conducted as part of a sentinel plant project, severe aphid infestations were observed on Widdringtonia trees in the Kirstenbosch National Botanical Garden, Cape Town, South Africa. In addition, planted Widdringtonia wallichii Endl. ex Carrière trees within their natural range of the Cederberg Wilderness Area, Western Cape, South Africa were found infested with aphids. In this study, we investigated the species identity of the aphids using DNA sequence data for the mitochondrial cytochrome c oxidase (COI) gene. The results revealed the presence of two closely related aphid species, the cypress aphid, Cinara cupressi (Buckton) and the cypress pine aphid, Cinara tujafilina (Del Guercio) infesting Widdringtonia spp. in South Africa. Both aphid species are alien to South Africa. While this is not the first report for either species in the country, the current study provides evidence of impact, with severe infestations leading to branch dieback and tree death. This finding supports the regulation of Cinara spp. in South Africa and highlights that management is urgently needed.

A snapshot in time: composition of native primary fauna of gall wasps in Spanish contact zones with chestnut trees infested by Dryocosmus kuriphilus.

One of the most prominent problems related to biological invasions is the variation of local species composition, which often leads to ex novo interspecific interactions. Here, we explored and analysed the native species composition of gall inducers and their associated parasitoids and inquilines in Spanish areas invaded by Dryocosmus kuriphilus Yasumatsu 1951 (Hymenoptera: Cynipidae), an invasive pest of chestnut trees. After a quantitative description of these species' assemblages, we analysed through bipartite networks the level of the trophic specialisation of parasitoids and inquilines when considering either the host taxonomic identity, the host plant species or the host gall morphological type. We sampled galls of D. kuriphilus and native species of Cynipidae in different Spanish areas, including those where the exotic parasitoid Torymus sinensis Kamijo 1982 (Hymenoptera: Torymidae) had been released for D. kuriphilus biological control. The results indicate that the native parasitoids recruited by D. kuriphilus come almost exclusively from native communities on Quercus galls, except for one species from Rosa. Galls of D. kuriphilus had the second most diverse species composition; despite this species assemblage arose ex novo in less than a decade. The bipartite networks resulted more specialised when considering host plant taxa than when gall types and the host taxa were accounted. In such trophic webs, there were few parasitoid/inquiline specialist and many generalist species, which agrees with the rapid recruitment by D. kuriphilus. Higher parasitoid species richness in D. kuriphilus galls is likely due to their being a largely unexploited available resource for the native natural enemies of cynipid wasps.

Salicylic Aldehyde and Its Potential Use in Semiochemical-Based Pest Control Strategies Against Trypophloeus binodulus.

The poplar bark beetle Trypophloeus binodulus (Coleoptera: Scolytidae) is a key pest of poplar trees (Malpighiales: Salicaceae, genus Populus) across northern Spain. However, among the more than 200 poplar clones available on the market, the clone USA 184-411 has the highest susceptibility to T. binodulus attacks. We tested the hypothesis that compounds released by the most susceptible poplar clone chemically mediate Trypophloeus binodulus behavior. The leaf and bark volatile chemical profile composition of host poplar Populus nigra L. (Salicaceae) clones were analyzed and tested on adult T. binodulus by electroantennography (EAG) and by monitoring their populations in baited traps in northern Spain. The collection of volatiles released by the leaves and bark of both clones by SPME revealed the emission of 53 components from different chemical classes. Salicylaldehyde dominated these collections of leaf volatiles and was more abundant in aerations of the more susceptible poplar clone (USA 184-411). The EAG response of adult beetles to salicylaldehyde was higher than that of any other plant odorants. In field trials, traps baited with salicylaldehyde + ethanol significantly captured more adults than all other treatments, irrespective of other lure components. The present study could aid in developing semiochemical-based management tactics against this important pest.

Study on Wax Secretion and Wax‐Secreting System of Mulberry Pest Paurocephala sauteri Enderlein (Hemiptera: Psyllidae)

ABSTRACTPaurocephala sauteri Enderlein is one of the most important pests of mulberry trees in the tropical and subtropical regions of China. This species by penetrating the veins on the back of leaves and buds of mulberry trees, nymphs and female adults can secrete wax, these wax accumulated on the mulberry leaves significantly affects photosynthesis and silkworm cultivation. Therefore, this study aimed to understand the wax‐secreting system and characteristics of wax secretion, expecting a potential strategy to control the species population. The main findings were as follows: scanning electron microscopy revealed that the nymphs and female adults secrete wax in long tubes with spherical ends, and male adults secrete honeydew. Additionally, the wax‐secreting system of the nymphs and female adults differ, the nymph owned a bending moon‐shaped wax‐secreting system, the wax‐secreting system first instar nymph consisted of one circle of rectangular, depressed cell, whereas the wax‐secreting system of second to fifth instar nymph made up of one circle of rectangular, depressed cell and one circle of round, depressed cell. There were a certain number of white pores inside of this depressed cell. Wax filaments produced by these pores are converted into a dense, tight and hollow the wax tube. Gas chromatography/mass spectrometer showed that the main constituents of P. sauteri wax are hydrocarbons. The wax tube as a water conservation pool during the P. sauteri developmental process. This physiological feature may be a key point for a potential strategy to control P. sauteri, even other secreting insects.

Investigations on Biology and Life Cycle of Pear Psylla, Cacopsylla pyricola Foerster

Pear psylla (Cacopsylla pyricola Foerster) is a significant pest of pear trees (Pyrus communis), causing extensive damage to pear orchards through feeding and the secretion of honeydew. A laboratory study was conducted at SKUAST - Kashmir to examine the biology and life cycle of Pear psylla, Cacopsylla pyricola Foerster under controlled conditions (32±2°C, 12:12 photoperiod, and 65±5 % RH). The results revealed that the incubation period lasted for 0.36 days. The insect undergone five nymphal instars, with a total nymphal period of 0.72 days. Adult psyllids exhibited a pre-oviposition period of 0.31 days, followed by an oviposition period of 1.34 days, with fecundity ranging from 400 to 650 eggs/female. Male psyllids lived slightly longer (62.55 days) than females (61.35 days). The study contributes valuable data for better understanding the biology of pear psylla, facilitating more effective pest management strategies in pear-growing regions.

Remote Sensing Technologies Using UAVs for Pest and Disease Monitoring: A Review Centered on Date Palm Trees

This review is aimed at exploring the use of remote sensing technology with a focus on Unmanned Aerial Vehicles (UAVs) in monitoring and management of palm pests and diseases with a special focus on date palms. It highlights the most common sensor types, ranging from passive sensors such as RGB, multispectral, hyperspectral, and thermal as well as active sensors such as light detection and ranging (LiDAR), expounding on their unique functions and gains as far as the detection of pest infestation and disease symptoms is concerned. Indices derived from UAV multispectral and hyperspectral sensors are used to assess their usefulness in vegetation health monitoring and plant physiological changes. Other UAVs are equipped with thermal sensors to identify water stress and temperature anomalies associated with the presence of pests and diseases. Furthermore, the review discusses how LiDAR technology can be used to capture detailed 3D canopy structures as well as volume changes that may occur during the progressing stages of a date palm infection. Besides, the paper examines how machine learning algorithms have been incorporated into remote sensing technologies to ensure high accuracy levels in detecting diseases or pests. This paper aims to present a comprehensive outline for future research focusing on modern methodologies, technological improvements, and direction for the efficient application of UAV-based remote sensing in managing palm tree pests and diseases.

New evidence on the spread in Catalonia of the invasive longhorn beetle, Xylotrechus chinensis, and the efficacy of abamectin control.

The invasive wasp-mimicking Tiger Longicorn Beetle, Xylotrechus chinensis, a potentially lethal pest of mulberry trees (Moraceae: Morus spp.), was first reported in Europe in 2018. In Catalonia its spread has been impressive: one district, four towns, 44km2 in February 2018; four districts, 12 towns, 378km2 in July 2020; seven districts, 65 towns, 1134km2 in December 2023. It is likely the infestation will spread further in the future, in particular along the Mediterranean coast from Spain to Greece. The flight period of this beetle in Mediterranean countries is expanding on both ends (from the end of April to mid-October), probably due to increasing temperatures because of climate change, although this should be further proved. The adult beetle life span is 18-23 days in insectaria, likely somewhat shorter in the wild since they do not feed and spend more energy flying outside. The single treatment with abamectin carried out in a Catalonian town in June 2022 on a sample of 24 trees (12 treated, 12 untreated) has been effective in reducing the infestation of this beetle in relation to untreated trees. But the reduction was not complete since new exit holes appeared during the summer of the following year. Therefore, an additional treatment carried out during the first ten days of October should be tested to achieve a better control of this pest. It would also be worthwhile trying a single treatment of abamectin in mid-July since it should be able to kill larvae hatching before the treatment and still have sufficient residual activity for larvae hatching after the treatment, and thus cover the entire activity period. Also, to get satisfactory mulberry tree protection, it is likely that treatments might have to be repeated for a few consecutive years. Yearly re-infestations from untreated public and/or private mulberry trees are also a concern and make short-term control of this pest difficult, no doubt accounting for the rapid spread of this beetle.

Biological Control of Aphids in China: Successes and Prospects.

Aphids are small, soft-bodied insects, and many are notorious pests of field crops, vegetables, fruit trees, ornamental plants, and trees. In China, there is an increasing emphasis on utilizing biological control agents, including aphidopathogenics, and selective pesticides for the management of aphids. In particular, preventive integrated pest management strategies with early interventions reduce the financial and environmental costs associated with treatments of outbreaks. Decades of progress have proved that biological control is a cost-effective and environmentally safe control option. Here, we review the history and progress of aphid control, with an emphasis on major natural enemies, mass-rearing, and conservation, and provide two successful cases, constraints, and future perspectives on aphid biological control in China.

Combined Analysis of Metabolomics and Transcriptome Revealed the Effect of Bacillus thuringiensis on the 5th Instar Larvae of Dendrolimus kikuchii Matsumura.

Dendrolimus kikuchii Matsumura (D. kikuchii) is a serious pest of coniferous trees. Bacillus thuringiensis (Bt) has been widely studied and applied as a biological control agent for a variety of pests. Here, we found that the mortality rate of D. kikuchii larvae after being fed Bt reached 95.33% at 24 h; the midgut membrane tissue was ulcerated and liquefied, the MDA content in the midgut tissue decreased and the SOD, CAT and GPx enzyme activities increased, indicating that Bt has toxic effects on D. kikuchii larvae. In addition, transmission electron microscopy showed that Bt infection caused severe deformation of the nucleus of the midgut tissue of D. kikuchii larvae, vacuoles in the nucleolus, swelling and shedding of microvilli, severe degradation of mitochondria and endoplasmic reticulum and decreased number. Surprisingly, metabolomics and transcriptome association analysis revealed that four metabolic-related signaling pathways, Nicotinate and nicotinamide metabolism, Longevity regulating pathway-worm, Vitamin digestion and absorption and Lysine degradation, were co-annotated in larvae. More surprisingly, Niacinamide was a common differential metabolite in the first three signaling pathways, and both Niacinamide and L-2-Aminoadipic acid were reduced. The differentially expressed genes involved in the four signaling pathways, including NNT, ALDH, PNLIP, SETMAR, GST and RNASEK, were significantly down-regulated, but only SLC23A1 gene expression was up-regulated. Our results illustrate the effects of Bt on the 5th instar larvae of D. kikuchii at the tissue, cell and molecular levels, and provide theoretical support for the study of Bt as a new biological control agent for D. kikuchii.

SIMPLE REARER AND YOUNG REVOLUTIONER

Insects are known as one of the most successful class of animals on earth, being a major player in the ecosystem. The economic importance of insects encompasses both their negative and positive importance. Often found on leaves, flowers and stems of crop plants, insects cause both direct (eat the leaves, fruits or vegetables of crop plants and many times too, do destroy the crops prior to fruiting) and indirect damage (transmit infections; viral, bacterial and fungal) to crops. Some insects are predaceous, they feed upon and destroy a large number of injurious insects. Stagomantis, a mantis is voracious, it feeds on flies, grasshoppers and caterpillars, some of which are injurious to crops. The larvae and adults of Chilomenes, a lady-bird beetle, feed on aphids which infect cotton plants. Novius, a lady-bird bettle, destroys scale worms which are pests of orange and lemon trees. Epicauta is a blister beetle, it deposits eggs where locusts occur, the larvae on hatching enter egg capsules of locusts and eat up masses of eggs. Calasoma, a ground beetle preys upon many kinds of lepidopterous larvae which destroy cereals and cotton. KEY WORDS: Honey bees, honey products, venom, royal jelly, pollen, propolis

The hindgut microbiota of coconut rhinoceros beetles (Oryctes rhinoceros) in relation to their geographical populations.

The coconut rhinoceros beetle (CRB, Oryctes rhinoceros) is a palm tree pest capable of rapidly expanding its population in new territories. Previous studies identified a digestive symbiosis between CRB and its gut microbes. However, no research compared the genetic variation of CRBs with their hindgut microbiota on a global scale. This study aims to investigate the genetic divergence of CRB and the compositional variation of CRB's microbiota across different geographical locations, and explore the association between them and their predicted functional profiles and environmental data. The research reveals a distinct and consistent microbial community within local populations, but it varies across different geographical populations. The microbial functional profiles linked to the production of digestive enzymes, including cellulases and ligninases, are nonetheless globally conserved. This suggests that CRBs employ specific mechanisms to select and maintain microbes with functional benefits, contributing to host adaptability, stress tolerance, and fitness. The CRB microbial communities did not appear to recapitulate the genetic variation of their hosts. Rather than depend on obligate symbionts, CRBs seem to establish similar digestive associations with whatever environmentally acquired microbes are available wherever they are, aiding them in successfully establishing after invading a new location.IMPORTANCECoconut rhinoceros beetles (CRBs) are notorious pests on Arecaceae plants, posing destructive threats to countries highly reliant on coconut, oil palm, and date palm as economic crops. In the last century, CRBs have rapidly expanded their presence to territories that were once free of these beetles. The United States, for instance, has officially designated CRBs as invasive and alien pests. Given their remarkable ability to swiftly adapt to new environments, their gut microbes may play a crucial role in this process. While the microbiota of CRBs vary depending on geographical location, these beetles consistently exhibit a functionally identical digestive association with locally acquired microbes. This underscores the significance of CRB-microbe association in shaping the adaptive strategies of this agricultural pest.

Effects of High-Temperature Stress on Biological Characteristics of Coccophagus japonicus Compere.

The parasitoid, Coccophagus japonicus Compere (Hymenoptera: Aphelinidae) is a dominant natural enemy of Parasaissetia nigra Nietner (Hemiptera: Coccidae), an important pest of rubber trees. Much of Chinese rubber is cultivated in hotter regions such as Yunnan and Hainan, exposing applied parasitoids to non-optimal temperatures. Therefore, C. japonicus must adapt to avoid temperature-related impacts on survival and population expansion. In this study, we monitored the survival rate, developmental duration, parasitism rate, and fecundity of C. japonicus during short-term exposures to 36 °C, 38 °C, and 40 °C for 2, 4, and 6 h, as well as continuous exposures to 32 °C and 34 °C for 3 days. The results show that short-term exposure to high-temperature stress leads to decreased survival rate of C. japonicus larvae and pupae, with survival rates declining as temperature and duration increase. High-temperature stress also delayed insect development, reduced mature egg production, shortened the body length of newly emerged females, and decreased female lifespans. Moreover, continuous high-temperature stress was found to significantly impact the development and reproduction of C. japonicus. Compared with the CK (27 °C), 3 d of continuous exposure to 34 °C prolonged developmental duration, shortened the body length and lifespan of newly emerged females, reduced survival rate and single female fecundity, and significantly decreased offspring numbers and parasitism rates. Temperatures of 36 °C, 38 °C, and 40 °C decreased the mortality time of adult females to 28.78, 16.04, and 7.91 h, respectively. Adverse temperatures also affected the insects' functional response, with 8 h of stress at 36 °C, 38 °C, and 40 °C causing the control efficiency of C. japonicus on P. nigra. This level of stress in the parasitoids was found to reduce the immediate attack rate and search effect, prolong processing time, and attenuate interference between small prey. Parasitoid efficiency was lowest following exposure to 40 °C. In this study, we determined the range of high temperatures that C. japonicus populations can tolerate under short- or long-term stress, providing guidance for future field applications.

A biosecurity perspective on urban trees in public and private spaces and trees available from nurseries

Urban trees are of high importance for healthy urban ecosystems. However, some trees are invasive plants that may ‘escape’ from urban areas into natural environments. Furthermore, invasive forest pests often arrive and establish in urban environments before they spread to forest ecosystems. Therefore, knowledge of tree species composition in urban areas is important for the biosecurity of cities and surrounding forests. Despite this, urban tree inventories often lack information on trees on private properties. To assess the potential role of urban areas as a source of invasive trees as well as invasive pests of trees, we compared the species composition of urban trees in public and private spaces in several Swiss cities and in tree nurseries (henceforth: ‘nurseries’) in Switzerland. We analysed the various data sets we compiled regarding invasive tree species, and examined how many trees are potential hosts for invasive quarantine pests of trees. We found no statistically significant difference in tree species composition in public and private urban areas, but the proportion of non-native trees was higher in private than in public spaces. Tree species available in nurseries and those present in cities were not significantly different, with larger urban tree inventories having a greater overlap with the species available in nurseries. Five of eight tree species considered invasive whose sale was banned since September 2024 were still on sale ten months before the ban came into force. All eight tree species were present in urban tree inventories. Importantly, between 91 % and 97 % of all urban trees in public and private spaces were suitable hosts for at least one quarantine forest pest. Given the pivotal role that urban trees play for the health of urban and peri-urban ecosystems, knowledge of tree species composition is essential from a biosecurity perspective. Our findings suggest that the combination of public urban tree inventories and trees available from nurseries can provide an estimate of the composition of private urban trees and can be useful for invasive species monitoring.

Assessing potential for biological control of Japanese giant silkworm Caligula japonica using Anastatus gansuensis, a thelytokous parasitoid firstly reported in Eupelmidae.

Caligula japonica, commonly known as Japanese giant silkworm (JGS), is a serious defoliating pest of fruit and forest trees in East Asia. To develop eco-friendly and cost-effective control methods for this pest, we evaluated the potential for biological control of JGS using its egg parasitoid Anastatus gansuensis reared on the Chinese oak silkworm (COS) Antheraea pernyi. We compared the reproductive traits and population increase potential of the parasitoid on JGS and COS eggs, as well as its functional response to host egg densities and mutual interference at different parasitoid densities. Anastatus gansuensis was confirmed to be strictly synovigenic, with most eggs maturing post-emergence, and produced <1% male offspring on both host eggs. Although A. gansuensis females reared from COS eggs had longer longevity and oviposition period, and higher fecundity and net reproductive rate compared to those reared from JGS eggs, the parasitoid had a higher intrinsic rate of increase on JGS than COS eggs. The parasitoid exhibited a type II functional response to increasing host densities, with mutual interference among foraging female wasps occurred at higher parasitoid densities. Our results indicate a high potential for biological control of JGS using A. gansuensis. The parasitoid can be efficiently reared on COS eggs and used against JGS. It may be essential to provide food for emerging adult parasitoids allowing time for egg maturation prior to the rearing or augmentative release of the parasitoid. Some mutual interference at high parasitoid rearing densities likely reduces per capita parasitization efficiency of A. gansuensis. © 2024 Society of Chemical Industry.

The first detection of the poplar bark aphid, Pterocomma populeum (Hemiptera: Aphididae), in Australia

AbstractPterocomma (Hemiptera: Aphidinae) are large aphids found across the northern hemisphere on various willow (Salix) and poplar (Populus) trees. We provide the first records of the Poplar Bark Aphid, Pterocomma populeum in Australia from Tasmania and New South Wales, a potential pest of poplar trees. Morphological character measurements and DNA (cytochrome oxidase subunit 1) sequences are provided along with discussions around difficulties in species separation.