Neotropical Entomology最新文献

Long non-coding RNAs (lncRNAs) are non-coding transcripts that regulate various biological processes in many species, including insects. Some lncRNAs have been found to be associated with insecticide resistance. In this study, 4177 lncRNAs between the susceptive strain (RP-S) and the imidacloprid-resistant strain (RP-R) in Rhopalosiphum padi by transcriptome sequencing were recognized, including 2401 intergenic lncRNAs, 970 intron lncRNAs, and 806 antisense lncRNAs. Two hundred fifty-eight differentially expressed lncRNAs were observed, including 77 lncRNA transcripts that were upregulated, while 181 lncRNA transcripts were downregulated in RP-R compared to that in RP-S targeting 628 differentially expressed mRNAs. They could be involved in imidacloprid resistance by modulating the expression of 11 P450s, 2 CCEs, 6 UGTs, and 14 ABC transporters. Furthermore, quantitative PCR (qPCR), RNA interference (RNAi), and imidacloprid bioassay analyses demonstrated that overexpressed lnc8676, lnc36817, and lnc48853 were involved in imidacloprid resistance. This study provided comprehensive information on the lncRNAs profile and provided evidence that lncRNAs play a key role in conferring insecticide resistance to R. padi and have significant potential to be used as targets for pest control strategies.

The Curculionoidea superfamily consists of approximately 62,000 species worldwide and 1700 species in Türkiye. These species are considered highly specialized phytophagous insects. Some are agricultural and forest pests, while others contribute to weed control or help detect desertification. Therefore, understanding the abundance and diversity of native Curculionoidea species across different ecosystems, as well as designing and implementing specific measures to prevent or manage their damage, is essential. In this study, we investigated the species composition, abundance, and diversity of the Curculionoidea community in various ecosystems distributed across the eastern Black Sea and northeastern Anatolia of Türkiye from 2010 to 2013. A total of 5580 individuals belonging to 32 species across two families were collected (2798 in 2010, 704 in 2011, 1314 in 2012, and 1764 in 2013). Of these, 3350 belonged to Curculionidae (1890 males; 1460 females) and 2230 belonged to Rhynchitidae (1180 males; 1050 females). The highest levels of abundance and diversity of Curculionoidea were observed during the early summer period, followed by the summer and autumn periods, respectively. Among the different ecosystems, the agroecosystem (fruit orchards) exhibited a higher abundance of Curculionoidea in the early summer, while the forest ecosystem (forest plants) showed higher diversity (H') during both the early summer and summer periods. This study enhances our understanding of Curculionoidea biodiversity in Türkiye and provides a foundation for conservation planning and integrated pest management strategies in vulnerable ecosystems.

Tropical rain forests are the most species rich terrestrial habitats on Earth, but their insect diversity is understudied, and it is unclear how many species are already scientifically described. A model group to study description patterns are tiger moths (Erebidae: Arctiinae), a species-rich moth clade that comprises subtaxa that differ considerably in appearance. We inventoried Arctiinae moths in a lowland rainforest in the Canandé and Tesoro Escondido Reserves, NW Ecuador, and sorted 12,335 individuals into 330 species, of which 303 had DNA barcode (COI) data extracted. We found 52 species of Lithosiini, 4 species of Arctiina, 17 species of Pericopina, 132 species of Phaegopterina, 52 species of Euchromiina and 71 species of Ctenuchina. A total of 45% of the species can be assigned by us to known named species, but the numbers vary considerably within the subtaxa: while in the conspicuous butterfly-like Pericopina 82% are described, this figure is only 26% for the smaller and cryptic Lithosiini, indicating a strong description bias even within a relatively well-known group of macromoths. This may indicate that particularly small and inconspicuous moth species have so far been neglected and that museum collections might often not be representative archives of insect diversity. Therefore, more systematic and non-biased collection campaigns should be carried out for better estimates of insect diversity. All 330 Arctiinae species are listed in three electronic catalogues, which contain all barcoded individuals as well as corresponding type material from museums, allowing a transparent and straightforward verification of all identifications. We constructed a preliminary phylogeny using literature data as backbone in combination with our DNA COI sequence data which provides a unique and useful data base for future studies in the Chocó rainforest.

The Andean weevil is an economically important insect that causes severe damage to potato crops in high Andean regions. This pest comprises three species (i.e., Premnotrypes latithorax, P. suturicallus, P. vorax) and although P. vorax was extensively reported in the Amazonas region, the lack of information on this insect hinders the understanding of their population dynamics. In this context, the Andean weevil was firstly identified as P. vorax. Then, the structure and genetic diversity of Andean weevil populations in the Amazonas region were evaluated. The cytochrome oxidase I (COI) gene was amplified from 75 individuals of P. vorax from the main potato-producing Amazonas regions (i.e., Jalca Grande, Lámud, Levanto, Leymebamba, Luya, and San Isidro del Maino). The phylogenetic analyses in the Andean weevil revealed a single cluster with short branches and no subclustering. Populations showed high levels of haplotypic diversity (Hd = 0.95423), high nucleotide diversity (Pi = 0.00651), significant intraspecific genetic variation (ca. 2.8%), and low genetic connectivity (F_ST = 0.33463). Overall, these results collectively support a scenario of ongoing gene flow and rapid population expansion driven by climatic factors, potentially facilitated by historical tuber seed introductions. This study contributes to a better understanding of the genetic structure and population dynamics of the Andean weevil P. vorax and will enable the adoption of appropriate control strategies against insects pest populations in the Amazonas region.

The tomato leafminer Tuta (Phthorimaea) absoluta (Lepidoptera: Gelechiidae) is a highly destructive invasive pest of tomato. Heat shock proteins (HSPs) are key molecular chaperones that mediate insect responses to environmental stress. Despite their central role, a comprehensive characterization of HSP genes in T. absoluta has been lacking. This study presents the first genome-wide identification of HSP genes in T. absoluta. Here, we performed a genome-wide identification and characterization of T. absoluta HSP genes. In total, 58 HSP genes were identified, including 23 sHSPs, 10 HSP60s, 20 HSP70s, and five HSP90s. Coding sequence lengths ranged from 405 to 3,741 base pairs, encoding proteins of 103-475 amino acids. Gene structure analysis showed that 58% of these HSPs lacked introns. Chromosomal mapping revealed multiple tandem duplications, particularly within the sHSP and HSP70 families. Phylogenetic analysis demonstrated that T. absoluta HSPs clustered by subfamily with strong conservation. RT-qPCR revealed significant upregulation of several HSP70 genes (TaHSP70-8, TaHSP70-9, TaHSP70-11, TaHSP70-12, TaHSP70-13, TaHSP70-14, TaHSP70-17, and TaHSP70-18) under high-temperature stress. These findings provide the first comprehensive catalog of HSPs in T. absoluta, establishing a molecular framework for future studies on stress adaptation and offering insights for pest management strategies.

This study examines the structure of mite (Acari) communities in oil palm (Elaeis guineensis Jacq.) foliage using a genus-level approach, focusing on plantations up to 5 years old. This developmental stage represents a key period for ecological interactions, as palms reach full canopy expansion and are more susceptible to pest colonization. The primary objective was to characterize the spatial distribution and trophic composition of mites (phytophagous and predatory) across leaf strata and adjacent spontaneous vegetation. Sampling was conducted in a stratified manner from the upper, middle, and lower leaflets of the palm crown, as well as from surrounding vegetation. A total of 10,530 individuals were collected from which 337 adult mites were selected and processed. Specimens were cleared using Evans' solution to facilitate microscopic identification. Taxonomic determinations were made to subfamily and genus levels. Phytophagous mites (n = 210) were predominantly from the Tetranychidae family, while predatory mites (n = 127) were primarily from the Phytoseiidae family. The middle leaflet stratum and the 3-year-old Dami Las Flores variety harbored the highest mite densities. In the surrounding vegetation, phytophagous mites were more abundant, whereas predatory mites showed stronger associations with plant species in the Fabaceae and Asteraceae families. Although species-level identification was not achieved, genus-level resolution was sufficient to reveal meaningful patterns in early-stage mite assemblages and offer a functional perspective useful for developing future biological control and integrated pest management strategies.

The lower Parnaíba River Valley is Brazil's main area for organic acerola Malpighia emarginata DC. (Malpighiaceae) production. Fruit flies (Diptera: Tephritidae) are one of the greatest obstacles to acerola cultivation. This study aimed to survey the biodiversity, population fluctuation, and trophic interactions of fruit flies and their parasitoids in commercial organic acerola orchards. Weekly samples were taken over 12 months in two orchards, using acerola fruits and McPhail traps. From 16,000 fruits, 18,675 pupae were recovered, resulting in specimens of Anastrepha obliqua (Macquart) (n = 1,815), Ceratitis capitata (Wiedemann) (n = 206), and the parasitoids Doryctobracon areolatus (Szépligeti) (n = 2,498), Opius bellus Gahan (n = 86), and Utetes anastrephae (Viereck) (n = 20) emerged. Trap collections revealed A. obliqua (n = 8,249) and males of Anastrepha spp. (n = 2,935), C. capitata (n = 138), and Anastrepha alveata (Stone) (n = 4). Anastrepha obliqua was the predominant species in both fruits and traps, while D. areolatus was the most abundant parasitoid species. Acerola fruits serve as key reservoirs for the reproduction of fruit flies and their parasitoids. The population fluctuation of fruit flies in acerola orchards changed throughout the year, influenced by weather factors like temperature and relative humidit, and host availability. In spring, there was a noticeable increase in infestation, adult emergence, and trap captures. This study also documented the first record of A. obliqua, A. alveata, O. bellus, and U. anastrephae in the lower Parnaíba River Valley, expanding knowledge of the natural distribution and tri-trophic interactions of these species across the Americas.

Invasive forest pests are among the greatest threats to global forestry, causing substantial economic losses and disrupting ecosystem dynamics worldwide. The recent detection of the North American woodwasp Sirex obesus (Hymenoptera: Siricidae) in Brazilian pine plantations poses a serious risk to South America's 4.6 million hectares of commercial pine forests. Here, we present the first comprehensive assessment of its invasion potential across the continent, combining species distribution modeling with a multi-factor invasion risk index. Using occurrence records from the species' native range, we modeled climatic suitability across South America and addressed invasion risk by integrating bioclimatic suitability, host distribution, proximity to invaded areas, and wood trade volumes with Brazil. Our model predicts suitable climatic conditions in 48% of South American pine plantation areas, particularly in montane and high-altitude regions along the Andean corridor and central-eastern Brazil. The mean temperature of the driest quarter was the most influential predictor of suitability. The invasion risk index identified southern Brazil, northeastern Argentina, Argentine Patagonia, and central Chile as the regions most vulnerable to the establishment, due to the convergence of extensive pine plantations, favorable climate, and either proximity to infested areas or intense trade connections with Brazil. These findings provide a foundation for targeted surveillance and phytosanitary measures aimed at preventing further spread. Early monitoring in high-risk regions, combined with stricter inspections of wood products, will be critical to avoiding widespread establishment and severe economic impacts across South American forestry.

Tetragonisca angustula, a widely distributed Brazilian stingless bee, is commercially valuable for national meliponiculture. Despite their crucial role in bee health, honey quality, and nutrient metabolism, the gut microbiota of these bees remains poorly studied. This study aimed to isolate and identify gut bacteria from T. angustula workers and assess their enzymatic activities (amylase, cellulase, invertase, proteases). Bees were collected from nest entrances and interiors and dissected for microbial culture in appropriate media. In this study, we isolated and identified 21 bacterial strains from worker guts, belonging to Firmicutes, Actinobacteria, and Proteobacteria, including genera such as Paenibacillus, Bacillus, Pantoea, and Pseudomonas. Among them, only two isolates Alkalicoccobacillus sp. (TaP 03) and an unidentified strain (Tetra 2P) showed broad enzymatic activity, with Tetra 2P presenting the highest enzyme indexes for amylase (3.13), cellulase (2.56), and protease (2.56). Invertase activity was also widespread, detected in most isolates. Quantitatively, Tetra 2P showed higher amylase (125.1 ± 7.6 mgAR·min⁻¹·mL⁻¹) and invertase (135.7 ± 17.4 mgAR·min⁻¹·mL⁻¹) activity. From 16 isolates, 12 showed significant invertase activity. These results suggest that gut-associated bacteria of this stingless bee may contribute to nutrient metabolism and honey quality through sucrose fermentation and polysaccharide degradation. This is the first study to isolate and identify bacteria from the gut of T. angustula. These findings could provide insights and contribute to future research on microbial functions and their potential applications in meliponiculture.

Baculoviruses are important bioinsecticides in integrated pest management, with in vivo production systems still predominant due to cost-effectiveness and scalability. However, inconsistencies in quality, such as viral infectivity and contamination, and polyhedra yield restrict their wider adoption. This study evaluated the infection dynamics of Spodoptera frugiperda multiple nucleopolyhedrovirus - Alphabaculovirus spofrugiperdae isolate 6 (SfMNPV6) in Spodoptera frugiperda larvae to determine the optimal harvest time for maximizing occlusion body (OB) yield. Larvae were exposed to three inoculum concentrations (1 × 10⁵, 1 × 10⁶, and 1 × 10⁷ OB/mL) and monitored daily from the third to the tenth day post-infection. We assessed larval survival, tegument color as an indicator of infection symptoms, and polyhedra yield. Results indicated dose-dependent variations in disease progression, with the infection peak occurring on days seven, eight, and ten for the highest to lowest inoculum concentrations, respectively. Pinkish tegument symptom was strongly correlated with maximum OB yield, making it a reliable visual indicator for harvest timing. Statistical modeling confirmed the relationship between tegument color and OB concentration, with pinkish larvae (symptomatic) significantly outperforming green (early infection stage) and gray (post-mortem period) larvae in virus production. This symptom-based monitoring provides a low-cost, non-invasive alternative to enhance timing in baculovirus harvest protocols. These findings suggest that optimizing harvest based on larval symptoms and dose-dependent infection dynamics can improve virus yield and product quality. This approach enhances the reliability of baculovirus-based bioinsecticides, providing a more effective production strategy to meet the increasing demand for biological control agents in sustainable agriculture, particularly as global pest pressures are intensified by climate change.