Insect odorant-binding proteins (OBPs) are the key proteins in insect olfactory perception and play an important role in the perception and discrimination of insects. Frankliniella occidentalis is a polyphagous pest and seriously harms the quality and yield of fruits, flowers and crops worldwide. Therefore, the discovery of OBPs has greatly improved the understanding of behavioural response that mediates the chemoreception of F. occidentalis. To identify the OBP gene of F. occidentalis and its sequence and expression, rapid amplification cDNA ends (RACE) and qRT-PCR reaction system were performed. The results showed that the sequence of FoccOBP9 gene was 846 bp and the reading frame was 558 bp, encoding 185 amino acid residues, a 3′ non-coding region of 195 bp and a 5′ non-coding region of 93 bp.The molecular weight of the protein was about 20.08 kDa, and the isoelectric point was 8.89. FoccOBP9 was similar to AtumGOBP and CnipOBP2 (30%), followed by BdorGOBP, DficGOBP, DsuzGOBP, AalbOBP38, CmarOBP6 and SexiOBP. Phylogenetic analysis of the FoccOBP9 demonstrated that the FoccOBP9 had a relatively close evolutionary relationship with SgreOBP1, AtumGOBP, HeleOBP3, CbowOBP17, CnipOBP2 and CpalOBP2. The prediction of secondary structure showed that FoccOBP9 protein contained 135 amino acid residues forming α-helix, 91 amino acid residues forming β-sheets and 24 amino acid residues forming β-turning. However, three-dimensional structure prediction showed that the FoccOBP9 protein skeleton was composed of six α-helices and the loops connecting these helices. Dynamic observation of the three-dimensional structure revealed that five α-helices (α1, α2, α4, α5, α6) were found in the structure. The expression profiles analysis revealed that FoccOBP9 are highly abundant in antenna significantly, followed by the head and belly, and almost no expression in the chest and foot. Therefore, the identification and analysis of OBP may be useful for monitoring and limiting the damage of F. occidentalis.

Mosquitoes, particularly Aedes aegypti, pose significant public health risks by transmitting diseases like dengue, zika and chikungunya. Bacillus thuringiensis var. israelensis (BTI) is a crucial larvicide targeting mosquitoes while sparing other organisms and the environment. This study evaluated the effects of sublethal BTI doses on Ae. aegypti larvae regarding mortality, development, adult emergence and size, using a wide-area spray application in an urban neighbourhood. Laboratory experiments with four BTI concentrations (0, 0.008, 0.02 and 0.04 ppm) assessed compensatory and over compensatory responses. The spray achieved over 90% larval mortality within 48 h, but accumulating sublethal doses could trigger compensatory and over compensatory effects, enhancing the fitness of survivors. A dose–response relationship was evident, with higher BTI concentrations leading to increased mortality, reduced longevity and fewer pupae. BTI exposure also skewed the sex ratio towards males and altered adult sizes, potentially affecting population dynamics and vectorial capacity. These findings highlight the effectiveness of BTI in Ae. aegypti control and the importance of understanding compensation, overcompensation and density-dependent effects. While wide-area BTI applications can reach inaccessible breeding sites and offer potent mosquito control, careful consideration of ecological and evolutionary consequences is crucial.

Juvenile hormone (JH) regulates multiple physiological functions in insects including growth, metamorphosis, and reproduction. Juvenile hormone epoxide hydrolase (JHEH) and juvenile hormone esterase (JHE) are degradative enzymes that metabolise JH, and JH receptor (methoprene-tolerant, Met) functions in the regulation of female reproduction and vitellogenesis. In this study, JH titres in Coccinella septempunctata adult females were determined using ultra high-performance liquid chromatography and tandem mass spectrometry; the JH titres ranged from 0.03 to 0.16 ng g−1 in 5- to 30-day-old female adults. JHEH, JHE, and Met expression were studied in different reproductive stages of C. septempunctata females by quantitative real-time PCR. JHEH transcription levels were highest in 25-day-old female adults and were 1.93-fold higher than expression levels in 5-day-old adults. JHEH and JHE expression levels were inhibited by the addition of JH to the artificial diet. Met expression in C. septempunctata supplied with 3 μl JH in artificial diet was similar to Met transcription in females supplied with an aphid diet, and the results showed that supplementation with 3 μl JH in 582.2 g of artificial diet was the most suitable for reproductive regulation of C. septempunctata. The results of this study provide important insights for the improvement of C. septempunctata artificial diets.

Significant differences in life-history traits between the southern population (S) and northern (N) population of the cabbage beetle Colaphellus bowringi make it an excellent model for studying inheritance in this insect. In the present study, we observed the life-history traits of pure strains, F1, reciprocal backcross and reciprocal F2 progeny under a photoperiod of L:D 15:9 h at 22 °C. The S population had shorter larval development time, longer pupal time, higher body weight, growth rate and weight loss compared with the N population. In the F1 testing, the larval development time and body weight in hybrid populations were intermediate between the parents, and the paternal parents played a greater role in determining the larval development time, while the maternal parents exhibited a greater role in determining the body weight. The pupal time of hybrid populations was significantly shorter than that of the parents. In the reciprocal backcross testing, both father and grandfather affected the larval development time, while both mother and grandmother affected the body weight. Consistently, in the reciprocal F2 cross testing, the grandfather was more influential in determining the larval development time, and grandmother was more important in determining the body weight. In all tested populations, females had greater body weight, higher growth rate and weight loss than males. Hybridization pattern did not affect sex dimorphism and sex ratio. Overall, these findings suggest that different pathways (maternal or paternal effects) were involved in the inheritance of various life-history traits in C. bowringi.

Bagrada bug, Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae), is an invasive pest of cole crops in the United States. Because it also feeds on widespread weeds and persists in natural habitats surrounding crop fields, conventional control strategies are often ineffective at providing long-term control. One egg parasitoid, Gryon aetherium Talamas (Hymenoptera: Scelionidae), is a promising biological control candidate because of its ability to parasitise B. hilaris buried eggs. Recently, adventive populations of G. aetherium were recovered from sentinel eggs in California along with a native egg parasitoid, Ooencyrtus californicus Girault (Hymenoptera: Encyrtidae). A better understanding of these parasitoid species’ spatial preference for foraging and their possible competitive interactions will help evaluate their host suppression potential. We compared the foraging abilities of these two parasitoid species for eggs deposited below and above ground. We also investigated the effect of interspecific competition on host suppression and the ability of O. californicus to parasitise eggs previously parasitised by G. aetherium. G. aetherium parasitised naturally and manually buried eggs, whereas O. californicus did not. In another experiment, O. californicus parasitised eggs glued to cards, but not in the presence of sand. Results suggest that G. aetherium may be negatively affected by the presence of O. californicus, and there was a slight but significant reduction in total host mortality when the parasitoids were present together. However, the inability of O. californicus to forage in soil likely limits negative interactions between these two species, and the two parasitoids may ultimately complement each other.

Understanding the interactive effects of temperature and diet on insect life cycles is crucial for effective pest management. Here, the influence of different temperatures and diets on the life cycle of Conogethes punctiferalis was investigated using the age-stage, two-sex life table analysis. The results support the hypothesis that temperature and diets (maize, apple, and artificial diet) significantly influence the entire life cycle performance of C. punctiferalis. The duration of larval development was significantly prolonged, whereas adult lifespan was shortened and showed lower reproductive capacity on apple and artificial diet than maize. The total pre-oviposition period was longer on apples than on maize and artificial diet at both temperatures (20, 26°C). The highest r (0.113 d−1), λ (1.128 d−1), R0 (57.213), and GRR (75.54) of C. punctiferalis were found on maize at 26°C, while the highest T (45.062) was found on apples. Similar results were obtained in the age-specific survival curves (sxj), fecundity (mx), maternity (lxmx), and reproductive value (vxj) of YPM on different host plants when exposed to 20°C. These findings highlight the need for further research into the complex interactions between temperature, diet, and insect life history traits to develop effective pest management strategies and enhance our understanding of insect ecology in agroecosystems.

Multiple mating is a behaviour observed across various polyandrous insect species. It is suggested that, in ladybirds, this strategy of multiple copulations is used to enhance fecundity and fertility through sperm replenishment. Studies on sperm depletion need to correlate fertility with the presence of spermatozoa in the spermatheca. This study investigates the role of sperm replenishment in the ladybird Cryptolaemus montrouzieri. We hypothesised that females of this species exhibit fecundity and fertility rates proportional to the number of sperm replenishment opportunities (constant, periodic or absent). We observed oviposition behaviour and hatching rates over 30 days, and simultaneously tested for sperm depletion in females that copulated once. We dissected the spermathecae at four post-copulation moments to count spermatozoa under a microscope. Our results indicate that a single copulation suffices to maintain fertility for at least 30 days. Females with constant replenishment opportunities exhibited higher fecundity but lower fertility and increased mortality, suggesting a reproductive cost associated with frequent mating. Females with no replenishment during the experiment, exhibited the highest hatchability rate and lowest oviposition. Periodic copulation resulted in optimal female mating rate, with average fertility and fecundity. A plausible hypothesis would be that paired females choose to fertilise fewer eggs from a single male but are unable to control the effects of the oviposition stimulus induced by the male's presence. These findings have implications for the management and rearing of C. montrouzieri in biological control programmes, optimizing mating strategies for mass production.

The canopy of forests as the ‘last biotic frontier’ has often been neglected in insect biodiversity studies because it is harder to access compared to the understorey, even in relatively well-known temperate ecosystems. We investigated the diversity, abundance, and body size patterns of macromoths (Lepidoptera) in the canopy and understorey in a central European deciduous forest. We collected moths at two sites during 19 trapping nights and three lunar phases between July and September 2021 using a weak ultraviolet light emitting diode (LED) lamp (LepiLED mini). Overall, we captured 4368 individuals (165 species) from 11 families. Based on a number of metrics, richness and diversity was significantly lower in the canopy than in the understorey. Non-metric multidimensional scaling ordinations show that communities largely overlap, but the proportion of species that only occur in the understorey was higher. While Noctuidae and Erebidae species were abundant in both strata, Geometridae species were most frequently observed in the understorey. We identified 16 indicator species for the understorey but only three for the canopy. Forewing length of moths in the canopy was on average 1.7 mm longer than of those in the understorey. Overall, the understorey is far more important for moths than the canopy in a temperate forest. The canopy is dominated by fewer and larger species and probably has a higher proportion of dispersers.

Parasitoids employ diverse oviposition strategies to enhance offspring survival and maximise fitness gains from hosts. Ladybird parasitoids, significant natural enemies of ladybirds, have the potential to disrupt biocontrol efforts, yet their biology and ecology remain poorly understood. This study investigated the host–parasitoid interaction among three sympatric larval endoparasitoids of Cheilomenes sexmaculata (Coleoptera: Coccinellidae): Homalotylus hemipterinus (Hymenoptera: Encyrtidae), Nothoserphus mirabilis (Hymenoptera: Proctotrupidae) and Oomyzus scaposus (Hymenoptera: Eulophidae). Our objective was to understand host instar preferences from five perspectives related to host profitability, handling difficulty or parasitism decision-making, and to examine the occupation rates of each parasitoid in different host instars. Host profitability was determined by development time, adult offspring dry mass, sex ratio, brood size, parasitism success rate and host handling time. Host handling difficulty was evaluated through host defensive behaviour and handling time. Parasitism decision-making was evaluated through acceptance rate and preference score that considered the first reaction of female wasp to the host. Results showed that each parasitoid responded differently to the host from various perspectives. However, the first two suitable hosts of these parasitoids overlap on the third instar host, with first to third instar hosts being ideal for H. hemipterinus, and third to fourth instar hosts being ideal for N. mirabilis and O. scaposus. In the field, the occupation rate of each parasitoid in third instar host was influenced by the population of N. mirabilis, implying its superior competitiveness. This study reveals the host instar preferences of ladybird parasitoids and highlights the potential for interspecific competition.

Post-harvest treatments are very critical in accepting the exported dates. However, stored dates are attacked by a wide range of stored pests causing serious damage to yield. Therefore, this study investigated the efficacy of treating stored dates variety Siwi with vapour heat on almond moth Ephestia cautella (Walker), the Indian meal moth Plodia interpunctella (Hübner), the saw-toothed grain beetle Oryzaephilus surinamensis Linnaeus, the red flour beetle Tribolium castaneum (Herbst), and the drugstore beetle Stegobium paniceum (L.) of stored dates. Additionally, the effects of vapour heat on the quality and microbial load of treated dates were examined. The tested insects were infested and randomly distributed to eight positions inside a vapour heat chamber at 46.5°C and 95% relative humidity for 30 min. The results showed that a 120 cm height from the vapour heat source led 100% mortality in all tested insects. Furthermore, the treatment of vapour heat had a great efficacy to eliminate infestations. Meanwhile, the vapour heat treatment slightly reduced the microbial load of stored dates, and non-significantly (P ≤ 0.05) affected the chemical and physical characteristics of the stored dates. Therefore, vapour heat is a safe and environmentally friendly insect pest control alternative for exported dates.

The family Streblidae is a significant grouping of dipteran insects within the superfamily Hippoboscoidea, which parasitizes the body surface of bats. With the global spread of bat-related pathogens in recent years, Streblidae has gained increasing attention due to its potential for pathogen transmission. A sample of Brachytarsina amboinensis was sequenced on the B. amboinensis were obtained, compared with available Streblidae mitogenomes, and the phylogeny of Hippoboscoidea was reconstructed. The results indicate that the mitochondrial genome of B. amboinensis exhibits a relatively high degree of conservation, with an identical gene count, arrangement, and orientation as the ancestral insect's genome. Base composition analysis revealed a strong bias towards A and T in the base composition. Selection pressure analysis indicated strong purifying selection acting on cox1. Pairwise genetic distance analysis showed that cox1 evolved at a relatively slow rate. Regarding phylogenetic relationships, the constructed phylogenetic trees using Bayesian inference and Maximum Likelihood methods supported the monophyly of the Hippoboscoidea, Glossinidae, Hippoboscidae, and Nycteribiidae clades, with high nodal support values. Our research confirmed the paraphyly of the families Streblidae. In the familial relations between Nycteribiidae and Streblidae, New World Streblidae share a closer kinship with Nycteribiidae. This contrasts with prior findings which indicated that Old World Streblidae share a closer kinship with Nycteribiidae. This study not only enhances the molecular database for bat flies but also provides a valuable reference for the identification and phylogenetic analysis of Streblidae.

Insects' development can be significantly impacted by various environmental factors, including temperature. Thus, this study aimed to investigate the effect of temperature on the predatory thrips, Scolothrips longicornis Priesner (Thysanoptera: Thripidae), which feeds on the strawberry spider mite, Tetranychus turkestani Ugarov and Nikolski (Trombidiformes: Tetranychidae). Under laboratory conditions (16:8 L:D, 75 ± 5% RH), the impact of various temperature regimens (15–37.5°C) on the development, population parameters, and mass production of S. longicornis was assessed. Additionally, an age-stage, two-sex life table of the species was constructed. The study revealed that S. longicornis' pre-adult developmental period decreased as temperature increased until 35°C, after which the developmental period increased. The longevity of both males and females displayed significant differences across the temperature range, with the longest lifespan observed at 15°C and the shortest at 37.5°C. At 26°C, the mean total fecundity of S. longicornis was significantly higher (53.52 eggs per female) than the fecundity observed at other temperature regimens. The intrinsic rate of increase (r) and finite rate of increase (λ) demonstrated the highest values at 35°C. While R0 increased as the temperature rose from 15 to 30°C, it rapidly decreased at 35 and 37.5°C. The findings of this study suggest that temperature plays a crucial role in enhancing the rate of development and reproduction of S. longicornis, and a temperature range of 26–30°C could be considered optimal for rearing and mass production of S. longicornis.

The generalist predatory mite, Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) is one of the most effective biocontrol agents to control the pests of many crops in indoor cultivations. In this study, the effects of the enriched diets of the second trophic level, i.e. the stored-product mite, Tyrophagus putrescentiae (Schrank) on the performance of N. cucumeris as the third trophic level was determined in a tritrophic system. In the first step, different pollens including almond, maize, date palm, castor bean, saffron, and cattail or different legume flours including pinto bean, lentil, black-eyed pea, chickpea, mung bean and broad bean as enrichment additives were added to the basic diet, i.e. a mixture of wheat bran and flour as a basic diet of T. putrescentiae. In the second step, to reveal the effects of the mentioned additives on the performance of N. cucumeris, the demographic parameters of the predator were determined when it was fed with the prey enriched with the additives. Our results indicated that N. cucumeris had higher performance by feeding on the prey reared on diets enriched by either pollens or legumes compared with the basic diet. Overall, there was no significant difference between pollen grains and some legume flours when the predatory mite was fed with them through its prey. Since legumes are more available and cost-effective food sources than pollens, they can be affordable supplementary diets for the mass rearing of N. cucumeris.

In December 2017 the Venetian Region (local Authority), financed the creation of the Operational Group (OG) ‘Serinnovation’, within the framework of the Rural Development Plan supported by the European Community. The OG aims at coordinating and spreading innovation in sericulture through mechanisation of processes and centralisation of some rearing steps, the use of waste as by-products and traceability to promote local productions. The project acts on perceived quality by increasing the added value, through production cost efficiency, and on the recovery of the waste material for further applications (circular economy). The final target was to develop a niche-process to obtain traceable ‘Made-in-Italy’ silk for the luxury market and non-textile applications. A first strategy to increase the efficiency of the process was to build an automatic leaf cutting machine to prepare the feed for the first three instars of the silkworm (Bombyx mori Linnaeus). This new machine – based on a patent – was validated through several tests and compared with the cutting system previously used. The study was completed by a bioassay of production and survival rate associated with the introduction of this innovation. The results showed that labour saving is in the order of 10% compared to a semi-manual process, the leaf quality is not affected, survival of larvae and silk production are not significantly different from the control. This methodology is proposed as a study case for other similar mechanisation processes in entomological production, as the impact of innovations on insect physiology should be carefully considered.

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.

Cadra cautella is a serious insect pest of stored figs and dates. The irradiation sensitivity of different development stages of C. cautella and large-scale testing of the proposed irradiation quarantine doses (50–500 Gy), were investigated. The impact of a PI dose of 400 Gy on the physiochemical and microbiological quality of dry dates (Bartamoda cv.) stored at room temperature was also investigated. An irradiation dose of 100 Gy prevented egg hatching in the F1 generation when 1–3 days old eggs were irradiated. Irradiation doses of 200 and 300 Gy prevented adult emergence when 2nd and 4th instar larvae were irradiated. When the pupae stage was irradiated, an irradiation dose of 400 Gy prevented the hatchability of F1 generation, indicating that this stage was the most radio-tolerant. The results of large-scale testing of the proposed phytosanitary irradiation dose (400 Gy) applied to 18, 0000 pupae resulted in no reproduction (zero hatching of F1 generation). There were no significant differences in the physiochemical properties of stored dates during the storage period at room temperature. Stable ESR signal intensity was recorded for 6 months in all parts of the irradiated fruits, and the intensity was highest in the kernel. The PI dose of 400 Gy also slightly reduced all microorganisms' counts. In conclusion, the dose level of 400 Gy stopped the reproduction potential of C. cautella. and they maintained the quality characteristics of dry date Bartamoda fruits during storage at room temperature for 6 months in tightly closed packages.

Triatomines (Hemiptera: Heteroptera: Reduviidae) are hematophagous insects, well-known for their vectorial role in transmitting Trypanosoma cruzi Chagas (Kinetoplastida: Trypanosomatidae) parasites, the etiological agent of Chagas disease. Trapping these insects would limit human-triatomine interaction and, thus, control the disease. In this context, there is a critical need for effective lures to control triatomines. Through double-choice bioassays, we investigated the preference of Triatoma infestans Klug, T. pallidipennis Stal, and Rhodnius prolixus Stal triatomines for: (a) volatiles from fermented products (various fermentation types and substrates) and (b) commercial insect lures. Furthermore, we identified the chemical composition of these volatiles through headspace collection using Solid Phase Micro Extraction coupled with Gas Chromatograph-Mass Spectrometer (HS-SPME-GC-MS). Volatiles from lactic fermentation and certain fermented fruits, along with commercial lures, attracted triatomines, while other products exhibited possible repellent or dislodging properties. These findings hold promise for the control of triatomines and, ultimately, Chagas disease.

Phytoplasmas are phloem-limited bacteria that are primarily transmitted by hemipteran insects and are emerging threats to Camptotheca acuminata Decne plants due to their associations with a witches’ broom disease. Despite numerous studies, there has been no report on insect transmission of phytoplasma among C. acuminata. Here, transmission characteristics of the leafhopper, Empoasca paraparvipenis Zhang and Liu, 2008 and the phytoplasma in plant leaves through PCR quantification are described. The interaction between C. acuminata-phytoplasma and insect vectors was examined by analysing the impact on the life characteristics and progeny population in a temperature-dependent manner. Phytoplasma-infected C. acuminata plant exhibited symptoms including shorter internodes, weak and clustered branches, shrunken and yellowed leaves, and red leaf margins. The acquisition and transmission time of bacterial-infected third-instar nymphs of insect vectors were 10 (11.11%) and 30 min (33.33%), respectively. A single insect vector can infect a plant after 72 h of feeding, and the incidence rate of disease increases with the number of insects following 11–100% from single to 20 insects. The development time of the infected insect vectors (1–3 instars) was significantly shorter than that of the healthy insects, and the development duration of instar individuals was longer. In progeny populations, the higher the phytoplasma concentration (88–0% for 1–5 instars nymph, female and male adults), the shorter the development time and the longer the adult lifetime (both male and female). These findings provided research evidence of phytoplasma transmission by insect vectors; however, further investigation of the mechanisms for prevention and management of phytoplasma diseases is needed.