Search Results (68)

Spalangia endius Walker, a pupal parasitoid of the alien invasive pest Zeugodacus cucurbitae (Coquillett), causes 33% host mortality. This study assessed whether combining S. endius with insecticides (abamectin, thiamethoxam, nitenpyram, emamectin benzoate, or beta-cypermethrin)—all effective against Z. cucurbitae—could enhance control efficacy. Among these, abamectin was the least toxic to adult S. endius. Surface contact treatments with 12 and 15 mg a.i./kg of abamectin did not significantly increase S. endius mortality. However, mixing 12 mg a.i./kg of abamectin into a honey solution to encourage ingestion decreased the survival, parasitism, and fecundity of S. endius. In olfactometer assays, S. endius adults avoided abamectin-treated host pupae, though prior exposure to abamectin mitigated this avoidance. The timing of abamectin soil application relative to host pupation and S. endius release affects host mortality. The most effective timing is spraying abamectin before host pupation (to expose Z. cucurbitae larvae) and then releasing S. endius. Field trials confirmed that combining abamectin (12 mg a.i./kg) with S. endius increased host mortality more than either treatment alone. In conclusion, abamectin (12 mg a.i./kg) is a suitable insecticide for combination with S. endius to control Z. cucurbitae. The application sequence should be spraying abamectin before hosts pupate and, only after that, releasing the parasitoid. Full article

The tomato leaf miner Phthorimaea (syn. Tuta) absoluta Meyrick (Lepidoptera: Gelechiidae) is invasive in many agricultural regions. Its larvae feed inside leaf mines or tomato fruits and are difficult to reach with plant protection products. In contrast, entomopathogenic nematodes (EPNs) are highly virulent and can search for larvae. The challenge is to formulate EPNs to remain protected on a sprayed leaf surface until they enter the mines. We tested 11 formulations, including 2 oils, 4 gels or thickeners, 2 surfactants, 2 UV protectants, water, and combinations with and without the EPN Steinernema carpocapsae (Weiser) RW14-G-R3a-2 (Rhabditida: Steinernematidae), under non-closed low-humidity conditions. Six tomato leaf experiments with 1000 EPNs sprayed per leaf showed that EPNs in 0.25 to 0.5% canola oil or in 5% alkyl polyglycoside surfactant were the most effective (26 to 37%). Other formulations and an insecticide had less or no effect. Seven other bioassays showed that most formulations did not adversely affect EPN survival or pathogenicity. We assume that formulations of EPNs can be further improved, such as with other flowable gels or combinations, and encourage investment in the development of practical and economic protective sprayable formulations of EPNs against leaf miners to reduce reliance on chemical insecticides. Full article

Zoos and botanical gardens have a special role in the promotion, presentation and conservation of biodiversity in urbanised environments. Additionally, they provide special habitats for alien and invasive species. The formerly used methods of biodiversity assessments (e.g., light trapping, transect counts, etc.) are mostly labour-intensive and/or not efficient enough. In the Zoo of Debrecen, the efficacy and suitability of a synthetic (FLO) and a semisynthetic (SBL) lure for this purpose were proven. The qualitative and quantitative compositions of a moderately rich moth assemblage including 52 moth species were revealed, and the appearance and population dynamics of three invasive (Helicoverpa armigera, Autographa gamma and Cydalima pespectalis) and nine harmful pest species were also recorded. The results proved that the lures tested and traps used provide an easy-to-use, standardised and relatively cheap method for Zoos and botanical gardens to assess their biodiversity even in the case of limited resources. Full article

Encarsia protransvena (Hymenoptera: Aphelinidae) is recorded here for the first time in Italy as a parasitoid of the whitefly Singhiella simplex (Hemiptera: Aleyrodidae), one of the most invasive alien pests of exotic Ficus species. Singhiella simplex, originating from the Oriental region, has established a global presence. Monitoring of the whitefly and its parasitoids was conducted in the southern areas of Italy, providing crucial insights into their distribution and interactions. The taxonomic identity of E. protransvena, was confirmed by scrutiny of morphological and molecular taxonomic characters. At the time of writing, we also obtained some specimens of Encarsia hispida from the host collected in Campania. We reserve the right to provide bio-ethological information on the species in the future. Comprehensive illustrations and diagnostic features are provided for the host and the parasitoids. An identification key is included for all Encarsia species associated with S. simplex, which provides a valuable tool to distinguish these aphelinid wasps for future research and applications in biological control programs. Full article

The release of herbivore-induced plant volatiles (HIPVs) has been recognized to be an important strategy for plant adaptation to herbivore attack. However, whether these induced volatiles are beneficial to insect herbivores, particularly insect larvae, is largely unknown. We used the two important highly polyphagous lepidopteran pests Spodoptera frugiperda and S. litura to evaluate the benefit on xenobiotic detoxification of larval exposure to HIPVs released by the host plant maize (Zea mays). Larval exposure of the invasive alien species S. frugiperda to maize HIPVs significantly enhanced their tolerance to all three of the well-known defensive compounds 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), chlorogenic acid, and tannic acid in maize and the two commonly used insecticides methomyl and chlorpyrifos. HIPV exposure also improved the larval tolerance of S. litura third instars to chlorogenic and tannic acids. Furthermore, larval exposure to either maize HIPVs or DIMBOA induced the activities of cytochrome P450 enzymes (P450s), glutathione-s-transferase (GST), and carboxylesterase (CarE) in the midguts and fat bodies of the two insects, while the induction was significantly higher by the two components together. In addition, the expression of four genes encoding uridine diphosphate (UDP)-glycosyltransferases (UGT33F28, UGT40L8) and P450s (CYP4d8, CYP4V2) showed similar induction patterns in S. frugiperda. Cis-3-hexen-1-ol, an important component in maize HIPVs, also showed the same functions as maize HIPVs, and its exposure increased larval xenobiotic tolerance and induced the detoxification enzymes and gene expression. Our findings demonstrate that HIPVs released by the pest-infested host plants are conductive to the xenobiotic tolerance of lepidopteran insect larvae. Hijacking the host plant HIPVs is an important strategy of the invasive alien polyphagous lepidopteran pest to counter-defend against the host plant’s chemical defense. Full article

Invasive alien species often undergo shifts in their ecological niches when they establish themselves in environments that differ from their native habitats. Leptocybe invasa Fisher et LaSalle (Hymenoptera: Eulophidae), specifically, has caused huge economic losses to Eucalyptus trees in Australia. The global spread of eucalyptus cultivation has allowed L. invasa to threaten plantations beyond its native habitat. It is, therefore, urgent to implement effective control measures to mitigate the impact of this pest. The optimized MaxEnt model was used to predict the potential global distribution of L. invasa based on occurrence data and environmental variables. The centroid shift, overlap, unfilling, and expansion (COUE) framework was employed to evaluate niche dynamics during the global invasion process by comparing the ecological niches of L. invasa in both native regions and regions affected by invasions (hereafter referred to as “invaded”). The results indicated that the distribution of L. invasa is primarily influenced by temperature, precipitation, and the human influence index variables. Its ecological niche was shown to have considerably expanded from native to invaded regions. Under future climate scenarios, the potential geographical distribution of L. invasa is projected to be concentrated primarily in East Asia, Southeast Asia, Western Europe, and Southern Oceania. In the future, the potentially suitable areas for the establishment of L. invasa are expected to further expand. This study provides a unified framework for exploring the niche dynamics of invasive alien species globally. Emphasizing early warning and control in uninvaded areas is crucial for minimizing L. invasa ecological and economic threats. Full article

The European spongy moth, Lymantria dispar dispar (L.) (Lepidoptera: Erebidae), originating from Eurasia, is found in Europe, Africa, and North America. Its polyphagous larvae infest deciduous and coniferous trees, causing severe damage during mass outbreak years. Thus, it is listed as one of the top 100 invasive alien species worldwide. The management and containment of this pest vary significantly between Europe and North America, with North America exhibiting a more robust response regarding the containment of the outbreaks. This study evaluates the current state of the European Union (EU-27) forests’ legal, political and cooperative protection frameworks concerning L. dispar dispar. We identified active and potential new stakeholders to assess the level of national and international collaboration in forest protection. We conducted a SWOT analysis to propose new strategies and solutions, aiming for enhanced cooperation in protecting EU forests from L. dispar dispar outbreaks. Our findings highlight the potential of new monitoring and reporting technologies and the importance of increased social and political awareness through social media and public campaigns. These measures would enable more centralized and coordinated efforts among member states. A few of the most significant results in each category of SWOT analysis are as follows: for strengths, a well-established network of EU and national stakeholders exists; for opportunities, emerging innovative technologies, such as IoT, AI, and 5G, are transforming our approach to forest protection; for weaknesses, there is a lack of informed choices regarding proactive measures to contain the outbreak due to a lack of centralized EU coordination and the inefficiencies of national state policies. Finally, the numerous threats to the well-being of EU forests competing for the attention of institutions and relevant stakeholders is by far one of the most important parameters regarding the threats to the EU’s forest protection. The study advocates for a unified, technologically advanced approach to manage and mitigate L. dispar dispar impacts in European forests, emphasizing the need for strengthened international cooperation and the strategic implementation of innovative solutions. Full article

Within the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) complex, two cryptic species, namely Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED), are important invasive pests affecting global agriculture and horticulture. They were introduced into China sequentially in the mid-1990s and around 2003, respectively. Subsequently, the latter invader MED has outcompeted the earlier invader MEAM1, becoming the dominant population in the field. Although extensive studies have explored the underlying mechanisms driving this shift, the contribution of population genetics remains notably underexplored. In this study, we analyzed the genetic diversity and structure of 22 MED and 8 MEAM1 populations from various regions of China using mitochondrial DNA sequencing and microsatellite genotyping. Our results indicate low and moderate levels of genetic differentiation among geographically separate populations of MED and MEAM1, respectively. Median-joining network analysis of mtCOI gene haplotypes revealed no clear geographic structuring for either, with common haplotypes observed across provinces, although MED had more haplotypes. Comparative analyses revealed that MED presented greater genetic diversity than MEAM1 on the basis of two markers. Furthermore, analysis of molecular variance supported these findings, suggesting that while some genetic variation exists between populations, a significant amount is also present within populations. These findings reveal the population genetics of the two invasive cryptic species of the B. tabaci complex in China and suggest that the disparities in genetic diversity drive the displacement of their populations in the field. This work also provides valuable information on the genetic factors influencing the population dynamics and dominance of these invasive whitefly species. Full article

How alien pests invade new areas has always been a hot topic in invasion biology. The spread of the Bactrocera dorsalis from southern to northern China involved changes in food sources. In this paper, in controlled conditions, we take Bactrocera dorsalis as an example to study how plant host transformation affects gut bacteria by feeding it its favorite host oranges in the south, its favorite host peaches and apples in the north, and feeding it cucumbers as a non-favorite host plant, thereby further affecting their fitness during invasion. The result showed that, after three generations of feeding on cucumbers, Bactrocera dorsalis took longer to develop as a larva while its longevity and fecundity decreased and pre-adult mortality increased. Feeding it cucumbers significantly reduced the overall diversity of gut microbiota of Bactrocera dorsalis. The relative abundance of Enterobacter necessary for survival decreased, while the Empedobacter and Enterococcus increased, resulting in decreased carbohydrate transport and metabolism and increased lipid transport and metabolism. Feeding Bactrocera dorsalis Empedobacter brevis and Enterococcus faecalis resulted in a 26% increase in pre-adult mortality and a 2–3 d increase in adult preoviposition period (APOP). Additionally, Enterococcus faecalis decreased the longevity of female and male adults by 17 and 12 d, respectively, and decreased fecundity by 11%. We inferred that the shifted plant hosts played an important role in posing serious harm to Bactrocera dorsalis invading from the south to the north. Therefore, after an invasion of Bactrocera dorsalis into northern China, it is difficult to colonize cucumbers for a long time, but there is still a risk of short-term harm. The findings of this study have established that the interactions between an insect’s food source and gut bacteria may have an important effect on insect invasions. Full article

In recent years, the integration of smartphone technology with novel sensing technologies, Artificial Intelligence (AI), and Deep Learning (DL) algorithms has revolutionized crop pest and disease surveillance. Efficient and accurate diagnosis is crucial to mitigate substantial economic losses in agriculture caused by diseases and pests. An innovative Apple^® and Android™ mobile application for citizen science has been developed, to enable real-time detection and identification of plant leaf diseases and pests, minimizing their impact on horticulture, viticulture, and olive cultivation. Leveraging DL algorithms, this application facilitates efficient data collection on crop pests and diseases, supporting crop yield protection and cost reduction in alignment with the Green Deal goal for 2030 by reducing pesticide use. The proposed citizen science tool involves all Farm to Fork stakeholders and farm citizens in minimizing damage to plant health by insect and fungal diseases. It utilizes comprehensive datasets, including images of various diseases and insects, within a robust Decision Support System (DSS) where DL models operate. The DSS connects directly with users, allowing them to upload crop pest data via the mobile application, providing data-driven support and information. The application stands out for its scalability and interoperability, enabling the continuous integration of new data to enhance its capabilities. It supports AI-based imaging analysis of quarantine pests, invasive alien species, and emerging and native pests, thereby aiding post-border surveillance programs. The mobile application, developed using a Python-based REST API, PostgreSQL, and Keycloak, has been field-tested, demonstrating its effectiveness in real-world agriculture scenarios, such as detecting Tuta absoluta (Meyrick) infestation in tomato cultivations. The outcomes of this study in T. absoluta detection serve as a showcase scenario for the proposed citizen science tool’s applicability and usability, demonstrating a 70.2% accuracy (mAP₅₀) utilizing advanced DL models. Notably, during field testing, the model achieved detection confidence levels of up to 87%, enhancing pest management practices. Full article

Microorganisms within insects play a vital role in maintaining the basal physiological functions of the insects, with olfactory signals as critical components of insect survival strategies. Leptocybe invasa (L. invasa), an invasive alien pest inflicting significant damage to eucalyptus trees, harbors a rich and varied bacterial community within its body. However, the impact of its endogenous bacteria and their microbial Volatile Organic Compounds (mVOCs) on the behavioral preferences of L. invasa remains unexplored to date. This study focused on nine cultivable and dominant endogenous bacterial strains within L. invasa. Using a Y-tube olfactometer, we investigated the behavioral responses of female L. invasa to the mVOCs emitted by these bacteria. Concurrently, gas chromatography–mass spectrometry (GC–MS) was employed to quantify the mVOCs produced by these endogenous bacteria. Our findings revealed that Staphylococcus sp. exhibited the highest attractiveness of L. invasa, whereas Microbacterium sp. and E. cloacae exerted the most significant avoidance effects. The analysis of the mVOCs further highlighted the significance of aldehyde compounds, notably 2,3,6-trichlorobenzaldehyde, and alkane compounds, such as eicosane, in mediating the repellency and attraction effects. These results contribute to a deeper understanding of the invasion mechanism of L. invasa and provide a scientific basis for developing novel biopesticides or elicitors. Full article

Invasive alien species (IAS) significantly affect global native biodiversity, agriculture, industry, and human health. Carpomya vesuviana Costa, 1854 (Diptera: Tephritidae), a significant global IAS, affects various date species, leading to substantial economic losses and adverse effects on human health and the environment. This study employed biomod2 ensemble models, multivariate environmental similarity surface and most dissimilar variable analyses, and ecological niche dynamics based on environmental and species data to predict the potential distribution of C. vesuviana and explore the environmental variables affecting observed patterns and impacts. Compared to native ranges, ecological niche shifts at invaded sites increased the invasion risk of C. vesuviana globally. The potential geographical distribution was primarily in Asia, Africa, and Australia, with a gradual increase in suitability with time and radiation levels. The potential geographic distribution centre of C. vesuviana is likely to shift poleward between the present and the 2090s. We also show that precipitation is a key factor influencing the likely future distribution of this species. In conclusion, climate change has facilitated the expansion of the geographic range and ecological niche of C. vesuviana, requiring effective transnational management strategies to mitigate its impacts on the natural environment and public health during the Anthropocene. This study aims to assess the potential threat of C. vesuviana to date palms globally through quantitative analytical methods. By modelling and analysing its potential geographic distribution, ecological niche, and environmental similarities, this paper predicts the pest’s dispersal potential and possible transfer trends in geographic centres of mass in order to provide prevention and control strategies for the global date palm industry. Full article

Citizen science reinforces the development of emergent tools for the surveillance, monitoring, and early detection of biological invasions, enhancing biosecurity resilience. The contribution of farmers and farm citizens is vital, as volunteers can strengthen the effectiveness and efficiency of environmental observations, improve surveillance efforts, and aid in delimiting areas affected by plant-spread diseases and pests. This study presents a robust, user-friendly, and cost-effective smart module for citizen science that incorporates a cutting-edge developed hyperspectral imaging (HI) module, integrated in a single, energy-independent device and paired with a smartphone. The proposed module can empower farmers, farming communities, and citizens to easily capture and transmit data on crop conditions, plant disease symptoms (biotic and abiotic), and pest attacks. The developed HI-based module is interconnected with a smart embedded system (SES), which allows for the capture of hyperspectral images. Simultaneously, it enables multimodal analysis using the integrated environmental sensors on the module. These data are processed at the edge using lightweight Deep Learning algorithms for the detection and identification of Tuta absoluta (Meyrick), the most important invaded alien and devastating pest of tomato. The innovative Artificial Intelligence (AI)-based module offers open interfaces to passive surveillance platforms, Decision Support Systems (DSSs), and early warning surveillance systems, establishing a seamless environment where innovation and utility converge to enhance crop health and productivity and biodiversity protection. Full article

Invasions of dendrophagous insects pose major threats to forest ecosystems and to the timber industry. The alien species bark beetle Polygraphus proximus Blandf. of Far Eastern origin has caused Siberian fir dieback in vast areas within several regions of Russia. Rapid spread of the pest and its outbreaks raise the issue of preserving the most important functions, including carbon sequestration, by the damaged forests. In this study, monitoring of carbon pool dynamics was carried out during 2012–2023 on four sample plots showing various degrees of damage in the southern taiga zone of Western Siberia in the Larinsky Landscape Reserve. Dynamics of the forest stands’ vitality were reflected in a rapid decline of the number of viable trees and an increase in amounts of deadwood, debris, and soil composition, resulting in a transformation of the natural biological carbon cycle in the native dark coniferous ecosystems. Full article

Invasive alien species (IAS) are a major biosecurity threat affecting globalisation and the international trade of agricultural products and natural ecosystems. In recent decades, for example, field crop and postharvest grain insect pests have independently accounted for a significant decline in food quantity and quality. Nevertheless, how their interaction and cumulative effects along the ever-evolving field production to postharvest continuum contribute towards food insecurity remain scant in the literature. To address this within the context of Africa, we focus on the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), and the larger grain borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae), two of the most important field and postharvest IAS, respectively, that have invaded Africa. Both insect pests have shown high invasion success, managing to establish themselves in >50% of the African continent within a decade post-introduction. The successive and summative nature of field and postharvest damage by invasive insect pests on the same crop along its value chain results in exacerbated food losses. This systematic review assesses the drivers, impacts and management of the fall armyworm and larger grain borer and their effects on food systems in Africa. Interrogating these issues is important in early warning systems, holistic management of IAS, maintenance of integral food systems in Africa and the development of effective management strategies. Full article