Identification of neuropeptides and their G protein-coupled receptors in the predatory stink bug, Arma custos (Hemiptera: Pentatomidae).

The predatory stink bug Arma custos has been selected as an effective biological control agent and has been successfully massly bred and released into fields for the control of a diverse insect pests. As a zoophytophagous generalist, A. custos relies on a complex neuropeptide signaling system to prey on distinct food and adapt to different environments. However, information about neuropeptide signaling genes in A. custos has not been reported to date. In the present study, a total of 57 neuropeptide precursor transcripts and 41 potential neuropeptide G protein-coupled receptor (GPCR) transcripts were found mainly using our sequenced transcriptome data. Furthermore, a number of neuropeptides and their GPCR receptors that were enriched in guts and salivary glands of A. custos were identified, which might play critical roles in feeding and digestion. Our study provides basic information for an in-depth understanding of biological and ecological characteristics of the predatory bug and would aid in the development of better pest management strategies based on the effective utilization and protection of beneficial natural enemies.

Predation and parasitism of naturally occurring and sentinel stink bug egg masses of Halyomorpha halys (Stål) and Nezara viridula (L.) (Hemiptera: Pentatomidae) in various southeastern habitats.

Stink bugs, including Halyomorpha halys (Stål) and Nezara viridula (L.), are agricultural pests that feed on fruit in a variety of crops. Monitoring predation and parasitism of stink bug egg masses furthers our understanding of potential biological control tactics. However, best practices for laboratory and field assessments of parasitism and predation of egg masses require further attention. We carried out a series of laboratory and field experiments to test whether parasitism and predation for three types of sentinel H. halys egg masses, fresh, frozen, and refrigerated, varied in agricultural commodities. In addition, we asked if predation and parasitism differed between sentinel and naturally occurring H. halys and N. viridula egg masses in soybean. In the laboratory, more H. halys eggs were parasitized by Trissolcus euschisti (Ashmead) (Hymenoptera: Scelionidae) if they were frozen or refrigerated compared to fresh eggs. Similarly, in the field, parasitism was higher for frozen egg masses than fresh. In 2018 and 2019, H. halys natural egg masses had higher parasitism and lower predation compared to sentinel egg masses in soybean. In a paired field test during 2020 and 2021, there was no difference in parasitism between H. halys natural and sentinel eggs, but much higher incidence of parasitism was detected in natural N. viridula egg masses than sentinel eggs. Collecting natural egg masses is the best methodology for field assessment of parasitism of stink bug egg masses; however, if natural egg masses are not easily available, deploying refrigerated sentinel egg masses is a good alternative.

Quality control applications for recovering an inbred colony of Bagrada hilaris (Hemiptera: Pentatomidae).

The invasive stink bug, Bagrada hilaris (Burmeister), recently became established in the southwestern United States and has become a major pest of broccoli and other cole crops. Due to concerns about its possible establishment in Florida, a colony of this pest was maintained in quarantine to conduct research on its environmental requirements. The colony was reared reliably with approximately 300 adults per generation but began to decline in generation 16. Due to unknown causes, only about 73 females were recovered to mate and oviposit during the final 46 days. However, a corresponding decrease in the number of mated pairs did not reduce the yield of eggs, nymphs, and adults per day, but the females were maintained for fewer than the normal 160 days per generation. Therefore, quality control procedures were implemented to increase the number of days the colony produced adults in subsequent generations. The goal of producing approximately 400 adults per generation was accomplished during 104, 160, and 156 days, respectively, in generations 17, 18, and 19. The purpose of this research was to develop quality control procedures for rearing B. hilaris, use the procedures to restore a colony in quarantine, and describe how quality control can be used to maintain small colonies of insects. Implementing quality control procedures when a colony is established can help to prevent its decline.

Effects of Taurine as Dietary Supplement on the Biological and Demographic Parameters of Nezara viridula (Heteroptera: Pentatomidae).

The southern green stink bug, Nezara viridula (L.) (Heteroptera: Pentatomidae), is a widely distributed pest of many economically important crops. Because of its economic impact, multiple examples of rearing methods and diets for N. viridula have been published. However, rearing this pest year-round consistently in all-vegetable diets has been challenging. Preliminary observations have shown that supplementing N. viridula diet with insect components improves the survival and reproduction of this insect. We hypothesized that taurine could be the nutrient present in insect components that was providing the benefits. Treatments consisting of three different watering regimes: 1) Reverse osmosis (RO) water only (W), 2) 2% taurine solution only (T), and 3) a choice between RO water and 2% taurine solution (T&W) were compared for their effects on life cycle and demographic parameters of N. viridula. Both taurine-containing treatments (T and T&W) resulted in a significant increase in nymphal and premating adult survival and egg viability as compared with treatment 'W'. Taurine supplementation did not have significant effect on fecundity and development time significantly increased in the 'T' treatment compared with W and W&T treatments. However, there were significant improvements in demographic parameters showing an increase in fitness levels after taurine supplementation. These results suggest that taurine is an important nutrient for N. viridula, which has been deficient in traditional diets consisting exclusively of vegetable components. Adoption of this new information will help to improve the survival of N. viridula in culture to facilitate this study to develop new methods for its control.

Characterisation of the Alarm Pheromone of Bathycoelia Distincta (Pentatomidae).

Bathycoelia distincta (Pentatomidae) is the dominant pest in South African macadamia orchards, where adults are responsible for causing severe yield losses. Similar to other hemipterans, B. distincta release volatile compounds from scent glands that can deter natural enemies and act as an alarm signal among conspecifics. The overall aim of this study was to characterise the alarm pheromone of B. distincta. We: (i) analysed the scent gland contents of individual adult B. distincta by gas chromatography-mass spectrometry (GC-MS), (ii) quantified volatiles released from live stink bugs after stress, and (iii) evaluated the electrophysiological and behavioural activity of alarm pheromone compounds with dose-response experiments. A blend of fourteen compounds was identified in the scent gland extracts of adult stink bugs. Of these, six compounds were detected in the effluvia of live stressed stink bugs [(E)-2-hexenal, (E)-2-decenal, tridecane, dodecane, (E)-4-oxohex-2-enal and (E)-2-decenyl acetate]. No qualitative or quantitative differences were observed between sexes. Tridecane was the most abundant compound, comprising ∼50% of total secretions. Only (E)-2-hexenal, (E)-2-decenal, and (E)-4-oxohex-2-enal elicited an antennal response in both sexes. Finally, exposure to a mixture of (E)-2-hexenal, (E)-2-decenal, and (E)-4-oxohex-2-enal resulted in an increase in the speed and distance travelled by walking bugs and a decrease in time spent resting compared to unexposed bugs. Our results show that the blend of (E)-2-hexenal, (E)-2-decenal, and (E)-4-oxohex-2-enal can induce an alarm response in B. distincta.

Trypanosomatids Associated in the Alimentary Canal of Bagrada hilaris (Hemiptera: Pentatomidae).

Bagrada hilaris (Burmeister) is an invasive pest of economically important crops in the United States. During physiological investigations of B. hilaris, a flagellated protozoan was discovered in the alimentary canal of many specimens. This manuscript characterizes the morphology and molecular identification of the trypanosomatid, which appears similar to trypanosomatids identified in other stink bug species. It has been identified as a species in the Blastocrithidia genus based on morphological characteristics and molecular analyses.

Gross Morphology of Diseased Tissues in Nezara viridula (Hemiptera: Pentatomidae) and Molecular Characterization of an Associated Microsporidian.

Nezara viridula (L.) (Hemiptera: Pentatomidae), commonly known in the U.S. as the southern green stink bug (SGSB), is a cosmopolitan, highly polyphagous feeder that causes severe damage to a wide range of agronomically important crops such as fruit, vegetable, grain, tobacco, and cotton, throughout much of the United States, and is a global pest of considerable ecological, agricultural, and economical interest. During dissection of female Nz. viridula, conspicuous black and brown spots or lesions were observed on various internal organs. To determine the cause of these spots or lesions, tissues of fat body, spermatheca, ovaries, and ovulated eggs were collected from healthy and infected individuals. The gross morphology of the spots was characterized, and the microorganisms associated with the infection were identified by amplicon sequencing of the V4 region of the small subunit rRNA gene. The presence of a microsporidian pathogen Nosema maddoxi, Becnel, Solter, Hajek, Huang, Sanscrainte, & Estep (Microsporidia: Nosematidae) which has been observed on other species of stink bug, was evidenced for the first time. The characterization of the gross morphology of this associated microsporidian may enable more rapid determination of microsporidia infection in stink bug colonies and field populations.

Benefits and costs of hosting facultative symbionts in plant-sucking insects: A meta-analysis.

Many animals have evolved associations with symbiotic microbes that benefit the host through increased growth, lifespan, and survival. Some interactions are obligate (essential for survival) while others are facultative (usually beneficial but not essential). Not all individuals host all facultative symbionts in a population, and thus there is probably a trade-off between the cost of hosting these symbionts and the benefits they confer to the host. Plant-sucking insects have been one of the most important models to test these costs and benefits experimentally. This research is now moving beyond the description of symbiont effects towards understanding the mechanisms of action, and their role in the wider ecological community. We present a quantitative and systematic analysis of the published evidence exploring this question. We found that whitefly and true bugs experience benefits through increased growth and fecundity, whereas aphids experience costs to their fecundity but benefits through increased resistance to natural enemies. We also report the lack of data in some plant-sucking groups, and explore variation in effect strengths and directions across aphid host, symbiont and plant species thus highlighting the importance of considering the context dependency of these interactions.

Flat on its back: the impact of substrate on righting methods of the brown marmorated stink bug, Halyomorpha halys.

Many animals, including insects, need to solve the problem of self-righting if inverted and substrate is one understudied factor that could affect righting ability. In this study we ask the questions, how does Halyomorpha halys self-right and does variation in substrate affect self-righting? To address our questions we used four substrates with different features and filmed H. halys righting response on each substrate (n = 22 individuals). We also used two synced cameras to film the most common righting method and quantified its kinematics. Self-righting metrics did vary depending on substrate in terms of diversity of righting methods used, duration of the successful righting event, number of fails per attempt, and stance width. We also determined that the symmetrical forward flip is the most common method used by H. halys. In the forward flip H. halys creates a tripod of support using the hindlegs and the tip of the abdomen to elevate the anterior portion of the body off the substrate and pitch forward onto its feet. In addition to demonstrating that substrate can impact self-righting and quantifying the symmetrical forward flip, we also provide a foundation for future explorations of sensory feedback and adaptive motor control using H. halys.

Characterization of Halyomorpha halys TAR1 reveals its involvement in (E)-2-decenal pheromone perception.

In insects, tyramine receptor 1 (TAR1) has been shown to control several physiological functions, including olfaction. We investigated the molecular and functional profile of the Halyomorpha halys type 1 tyramine receptor gene (HhTAR1) and its role in olfactory functions of this pest. Molecular and pharmacological analyses confirmed that the HhTAR1 gene codes for a true TAR1. RT-qPCR analysis revealed that HhTAR1 is expressed mostly in adult brain and antennae as well as in early development stages (eggs, 1st and 2nd instar nymphs). In particular, among the antennomeres that compose a typical H. halys antenna, HhTAR1 was more expressed in flagellomeres. Scanning electron microscopy investigation revealed the type and distribution of sensilla on adult H. halys antennae: both flagellomeres appear rich in trichoid and grooved sensilla, known to be associated with olfactory functions. Through an RNAi approach, topically delivered HhTAR1 dsRNA induced a 50% downregulation in gene expression after 24 h in H. halys 2nd instar nymphs. An innovative behavioural assay revealed that HhTAR1 RNAi-silenced 2nd instar nymphs were less susceptible to the alarm pheromone component (E)-2 decenal as compared with controls. These results provide critical information concerning the role of TAR1 in olfaction regulation, especially alarm pheromone reception, in H. halys. Furthermore, considering the emerging role of TAR1 as target of biopesticides, this work opens the way for further investigation on innovative methods for controlling H. halys.

Escaping the evolutionary trap: Can size-related contest advantage compensate for juvenile mortality disadvantage when parasitoids develop in unnatural invasive hosts?

The quality of hosts for a parasitoid wasp may be influenced by attributes such as host size or species, with high quality for successful development usually coincident with high quality for larger offspring. This is not always the case: for the Scelionid wasp Trissolcus basalis, oviposition in eggs of the Brown Marmorated Stink Bug, Halyomorpha halys, rather than of the normal host, the Southern Green Stink Bug, Nezara viridula, leads to lower offspring survival, but survivors can be unusually large. Adult female T. basalis engage in contests for host access. As larger contestants are typically favoured in contests between parasitoids, the larger size of surviving offspring may compensate for the mortality of others. We construct a general game-theoretic model to explore whether size advantage can sustain a maternal preference to utilize a more deadly host species. We find that size advantage alone is unlikely to sustain a shift in host preference, yet such an outcome is possible when size asymmetries act simultaneously with advantages in host possession (ownership effect). Halyomorpha halys is an invasive pest of major agro-economic importance in Europe and the Americas, and use of its eggs as hosts by native parasitoids such as T. basalis has been seen as an evolutionary trap due to their high developmental mortality. Our model suggests that the recently discovered effect of host choice on offspring size may provide an escape from the trap via effects on contest biology of T. basalis which could foster a more stable association with H. halys. An evolutionary shift in the reproductive value of H. halys could increase the efficiency of T. basalis as a biological control agent of this invasive stink bug pest.

Up-Regulated Salivary Proteins of Brown Marmorated Stink Bug Halyomorpha halys on Plant Growth-Promoting Rhizobacteria-Treated Plants.

Plant Growth-Promoting Rhizobacteria (PGPR) induce systemic resistance (SR) in plants, decreasing the development of phytopathogens. The FZB42 strain of Bacillus velezensis is known to induce an SR against pathogens in various plant species. Previous studies suggested that it could also influence the interactions between plants and associated pests. However, insects have developed several strategies to counteract plant defenses, including salivary proteins that allow the insect escaping detection, manipulating defensive pathways to its advantage, deactivating early signaling processes, or detoxifying secondary metabolites. Because Brown Marmorated Stink Bug (BMSB) Halyomorpha halys is highly invasive and polyphagous, we hypothesized that it could detect the PGPR-induced systemic defenses in the plant, and efficiently adapt its salivary compounds to counteract them. Therefore, we inoculated a beneficial rhizobacterium on Vicia faba roots and soil, previous to plant infestation with BMSB. Salivary gland proteome of BMSB was analyzed by LC-MS/MS and a label-free quantitative proteomic method. Among the differentially expressed proteins, most were up-regulated in salivary glands of insects exposed to PGPR-treated plants for 24 h. We could confirm that BMSB was confronted with a stress during feeding on PGPR-treated plants. The to-be-confirmed defensive state of the plant would have been rapidly detected by the invasive H. halys pest, which consequently modified its salivary proteins. Among the up-regulated proteins, many could be associated with a role in plant defense counteraction, and more especially in allelochemicals detoxification or sequestration.

Population genetics of the brown marmorated stink bug Halyomorpha halys in the early phase of invasion in South Tyrol (Northern Italy).

The brown marmorated stink bug Halyomorpha halys is one of the most harmful invasive species in the world. Native to East Asia, this insect was introduced into North America in the 1990s and into Europe in the 2000s where it subsequently established and spread across the continent. Previous population genetic studies determined the invasion pathways at continental and national levels. However, information on the dynamics on a small-scale is currently scarce. Here we study the genetic diversity and population dynamics of H. halys in South Tyrol, a region in Northern Italy, since its arrival to its widespread establishment over a period of four years. By haplotyping 162 individuals from ten populations (including six previously published individuals) we found a high haplotype diversity in most populations with an increasing diversity across the different years. Most haplotypes were previously found in other regions of Northern Italy, providing evidence for migration from neighboring regions. However, the presence of four previously undescribed haplotypes as well as a haplotype previously found exclusively in Greece highlights additional long-distance dispersal across the continent. Phylogenetic analysis of the haplotypes found in South Tyrol showed that the majority of haplotypes clustered with haplotypes predominantly found in Japan. This suggests a potential recent introduction of H. halys individuals from Japan into Europe, and thus an additional invasion pathway that was previously unidentified.

Acquisition and Transmission of Fusarium oxysporum f. sp. vasinfectum VCG 0114 (Race 4) by Stink Bugs.

Fusarium oxysporum f. sp. vasinfectum VCG 0114 (race 4; i.e., FOV4) is an emerging pathogen that causes severe root rot and wilt of cotton. FOV4 is seed-borne, but the mode of seed invasion is uncertain. In an initial study, seeds in bolls that were puncture inoculated with FOV4 conidia when they were 25- or 30-days old became infected but remained viable. Because stink bugs can ingest and introduce bacterial and yeast pathogens into cotton bolls, we hypothesized that stink bugs may ingest and transmit FOV4. Southern green stink bugs and brown stink bugs were exposed to potato dextrose agar cultures of FOV4 and subsequently caged with cotton bolls to assess transmission potential. Both species fed on the cultures and acquired FOV4, and brown stink bugs transmitted FOV4 to cotton bolls. Thus, management of FOV4 may require management of stink bugs to mitigate the spread of the disease in cotton.

Brown Stink Bug (Hemiptera: Pentatomidae) Damage to Seedling Corn and Impact on Grain Yield.

Brown stink bugs, Euschistus servus, are an important early-season pest of field corn in the southeastern United States. Feeding in the early stages of corn development can lead to a number of growth deformities and deficiencies and, ultimately, a reduction in yield. An observational and two experimentally manipulated trials were conducted in 2017 and 2018 to 1) determine optimal timing for assessing brown stink bug damage, 2) assess the level of damage from which yield compensation can occur, and 3) examine the relationship between brown stink bug density and early-season damage and yield. Fields were identified with infestations of brown stink bugs and a damage rating system for early stages of corn was established. Varying rates of brown stink bug densities were introduced using field cages and damage was assessed throughout the season. The density and duration of stink bug infestations were critical factors for damage potential, with each day of active feeding per plant resulting in a loss of ~14 kg/ha in yield. The level of damage in early stages of corn was categorized into easily identifiable groups, with only the most severe damage leading to a reduction in yield. Moderate and minimal feeding damage did not result in yield loss. This study emphasizes the need for early and frequent scouting of corn to determine the risk of damage and yield loss from brown stink bugs. Results from this study can be used to help develop management programs for brown stink bugs in the early vegetative stages of field corn.

Development of a Method for Rearing Nezara viridula (Heteroptera: Pentatomidae) on a Semi-solid Artificial Diet.

A method for rearing the southern green stinkbug, (Nezara viridula L.) (Heteroptera: Pentatomidae), using a modified lygus semi-solid artificial diet was developed. First to second-instar nymph were reared in a density of 631.5 ± 125.05 eggs per Petri-dish (4 cm deep × 15 cm diam). Second instar to adult were reared in a density of 535.0 ± 112.46 s instar nymphs per rearing cage (43 × 28 × 9 cm). Mating and oviposition occurred in popup rearing cages (30 × 30 cm), each holding 60-90 mixed sex adults of similar age. Adults emerged 35.88 ± 2.13 d after oviposition and survived for an average of 43.09 ± 9.53 d. On average, adults laid 223.95 ± 69.88 eggs in their lifetime, for a total production of 8,099 ± 1,277 fertile eggs/oviposition cage. Egg fertility was 77.93% ± 16.28. Egg masses held in petri-dishes had a total hatchability of 79.38% ± 20.03. Mortality of early nymphs in petri-dishes was 0.64% ± 0.12 for the first instar and 1.37% ± 0.45 for second instar. Late nymphal mortality in rearing cages was 1.41% ± 0.10, 3.47% ± 1.27, and 4.72% ± 1.29 for the third, fourth, and fifth instars, respectively. Survivorship from nymphs to adults was 88.48% ± 2.76. Using artificial diet for rearing N. viridula could reduce cost by avoiding time-consuming issues with daily feeding fresh natural hosts and insect manipulation. It could increase reliability and simplicity of bug production, which should facilitate mass rearing of its biological control agents.

A transcriptomic and proteomic atlas of expression in the Nezara viridula (Heteroptera: Pentatomidae) midgut suggests the compartmentalization of xenobiotic metabolism and nutrient digestion.

BACKGROUND: Stink bugs are an emerging threat to crop security in many parts of the globe, but there are few genetic resources available to study their physiology at a molecular level. This is especially true for tissues such as the midgut, which forms the barrier between ingested material and the inside of the body. RESULTS: Here, we focus on the midgut of the southern green stink bug Nezara viridula and use both transcriptomic and proteomic approaches to create an atlas of expression along the four compartments of the anterior-posterior axis. Estimates of the transcriptome completeness were high, which led us to compare our predicted gene set to other related stink bugs and Hemiptera, finding a high number of species-specific genes in N. viridula. To understand midgut function, gene ontology and gene family enrichment analyses were performed for the most highly expressed and specific genes in each midgut compartment. These data suggested a role for the anterior midgut (regions M1-M3) in digestion and xenobiotic metabolism, while the most posterior compartment (M4) was enriched in transmembrane proteins. A more detailed characterization of these findings was undertaken by identifying individual members of the cytochrome P450 superfamily and nutrient transporters thought to absorb amino acids or sugars. CONCLUSIONS: These findings represent an initial step to understand the compartmentalization and physiology of the N. viridula midgut at a genetic level. Future studies will be able to build on this work and explore the molecular physiology of the stink bug midgut.

Brown marmorated stink bug, Halyomorpha halys (Stål), genome: putative underpinnings of polyphagy, insecticide resistance potential and biology of a top worldwide pest.

BACKGROUND: Halyomorpha halys (Stål), the brown marmorated stink bug, is a highly invasive insect species due in part to its exceptionally high levels of polyphagy. This species is also a nuisance due to overwintering in human-made structures. It has caused significant agricultural losses in recent years along the Atlantic seaboard of North America and in continental Europe. Genomic resources will assist with determining the molecular basis for this species' feeding and habitat traits, defining potential targets for pest management strategies. RESULTS: Analysis of the 1.15-Gb draft genome assembly has identified a wide variety of genetic elements underpinning the biological characteristics of this formidable pest species, encompassing the roles of sensory functions, digestion, immunity, detoxification and development, all of which likely support H. halys' capacity for invasiveness. Many of the genes identified herein have potential for biomolecular pesticide applications. CONCLUSIONS: Availability of the H. halys genome sequence will be useful for the development of environmentally friendly biomolecular pesticides to be applied in concert with more traditional, synthetic chemical-based controls.

Biosecurity Dogs Detect Live Insects after Training with Odor-Proxy Training Aids: Scent Extract and Dead Specimens.

Detector dogs could be trained to find invasive insect pests at borders before they establish in new areas. However, without access to the live insects themselves, odor training aids are needed to condition dogs to their scent. This proof-of-concept study assessed 2 potential training aids for insect detection: a scent extract and dead specimens of the target species. Using Musgraveia sulciventris (Hemiptera: Tessaratomidae) as an experimental model, gas chromatography-mass spectrometry (GC-MS) analyses were carried out to compare the chemical headspaces that make up the odors of live specimens and these 2 training aids. This was then followed by canine scent-detection testing to investigate biosecurity detector dogs' (n = 4) responses to training in an ecologically valid context. Both the scent extract and the dead specimens shared the majority of their volatile organic compounds (VOCs) with live insects. Of the dogs trained with scent extract (n = 2), both were able to detect the live insects accurately, and of those trained with dead specimens (n = 2), one detected the live insects accurately. These findings lend support for these training aids as odor-proxies for live insects-particularly scent extract, which is a relatively novel product with the potential for broad application to facilitate and improve insect-detection training.

Suitable reference genes for RT-qPCR analysis in Dichelops melacanthus (Hemiptera: Pentatomidae).

The relative quantification of gene expression is mainly realized through reverse transcription-quantitative PCR (RT-qPCR). However, the accuracy of this technique is deeply influenced by the expression stability of the reference genes used for data normalization. Therefore, the selection of suitable reference genes for a given experimental condition is a prerequisite in gene expression studies. Dichelops melacanthus (Hemiptera: Pentatomidae) is an important phloem sap-sucking insect pest of soybean, wheat, and maize in Brazil. Most of the genetic and molecular biology studies require gene expression analysis. Nevertheless, there are no reports about reference genes for RT-qPCR data normalization in D. melacanthus. In this study, we evaluated the expression stability of nine candidate reference genes (nadh, sdhb, gapdh, fau, ef1a, rpl9, ube4a, gus and rps23) in different developmental stages, body parts, sex, starvation-induced stress and dsRNA exposure by RefFinder software that integrates the statistical algorithms geNorm, NormFinder, BestKeeper, and ΔCt method. Our results showed that ef1a and nadh are the most stable reference genes for developmental stages, fau and rps23 for sex, ube4a and rps23 for body parts, rpl9 and fau for starvation stress, and nadh and sdhb for dsRNA exposure treatment. The reference genes selected in this work will be useful for further RT-qPCR analyses on D. melacanthus, facilitating future gene expression studies that can provide a better understanding of the developmental, physiological, and molecular processes of this important insect pest. Moreover, the knowledge gained from these studies can be helpful to design effective and sustainable pest management strategies.