Pieris brassicae (Linnaeus, 1758) (Lepidoptera: Pieridae), commonly known as the cabbage butterfly, is a major herbivorous pest causing significant damage to Brassica crops, which are widely cultivated for edible parts and economic uses such as oilseed production. Conventional chemical-based pest control methods pose risks to environmental and human health, prompting interest in sustainable alternatives like biological control using parasitoids. This study evaluated crop damage by P. brassicae larvae and the potential of the larval parasitoid Cotesia vestalis (Haliday, 1834) (Hymenoptera: Braconidae) in managing pest populations. Larvae and fertilized eggs of P. brassicae were collected and reared on four host diets (cabbage, cauliflower, turnip, and generic brassica) under controlled laboratory conditions. Larval growth, feeding behavior, and development were assessed, along with a feeding index for dietary efficiency. Parasitisation was introduced by exposing larvae to adult C. vestalis, and host-parasitoid interactions were statistically analyzed using one-way ANOVA and regression models. Results revealed that larvae had the highest feeding preference and weight gain on brassica, while turnip-fed larvae consumed the least. Parasitisation by C. vestalis significantly suppressed larval development, with a strong correlation between parasitisation rates and reduced host fitness. These findings highlight C. vestalis as a promising biological control agent for P. brassicae, offering an effective and eco-friendly alternative to chemical pesticides. Further research should focus on optimizing C. vestalis mass-rearing protocols and release strategies tailored to diverse Brassica cropping systems to promote sustainable pest management.

The effects of rainfall and temperature on the seasonal phenology of ant nuptial flights in a forest locality in Ghana was studied for 42 months using a light-trap. A total of 204393 ants was caught. Of the 135 species/morphospecies collected, 40 could not be identified beyond genus, and males of a further 14 beyond subfamily. The commonest 65 species/morphospecies flew a mean of 10.1 ± 0.4 months per year. With the exception of males of Dorylus atriceps, Platythyrea conradti, Plat. modesta, Crematogaster nr striatula plus gynes of Plagiolepis brunni and Cr. [F257], whose peak flights occurred in the main dry season, flight activity coincided with the onset of the rainy seasons. Both sexes of Pheidole megacephala, P. speculifera, Tetramorium aculeatum, and Paraparatrechina albipes plus gynes of Cr. striatula and males of Anochetus africanus, Hypoponera dulcis, Cr. kneri, and T. guineensis flew more frequently on rainy than dry dates. Nineteen species were caught more frequently on dry than on wet dates including most Camponotus, Tapinoma, and Technomyrmex spp. Fifteen species/morphospecies responded positively to increasing monthly rainfall, six to increasing monthly temperatures, and five to the interaction between these factors, with males of A. pellucidus, H. dulcis, and Cr. striatula caught more frequently in wetter, warmer months, and those of Camponotus olivieri and Technomyrmex andrei in drier, warmer ones.

Coccygidium luteum (Hymenoptera: Braconidae), a solitary larval parasitoid, is associated with the fall armyworm (FAW), in Africa. However, there is very limited information on reproductive biology, and other biological parameters that influence its life strategies. We conducted laboratory experiments to gain new insights into the biology of C. luteum reared on FAW as the host. Host age preference, reproductive biology, lifetime fecundity, life cycle, and adult longevity were studied under laboratory conditions of 28 ± 1°C and 70 ± 3% relative humidity. This study revealed that C. luteum prefer early (1st–3rd) instars of FAW for oviposition. The maximum parasitism rate was 80% at second instar larvae. A mean pre-oviposition period of 0.38 ± 0.51 days, oviposition period of 5.13 ± 0.64 days, and no post-oviposition period were observed. The mean lifetime parasitism rate of FAW larvae by female C. luteum was 49 ± 24. Longevity of unmated C. luteum was 14.44 ± 1.43 days for males and 12.83 ± 1.12 days for females. Mated ovipositing females lived for 7 days. Mean female and male progenies per adult female C. luteum was 28.11 ± 8.18 and 39.89 ± 4.76 respectively, with an overall sex ratio of 1.42 at 28 ± 1°C using second instar larvae. Total life cycle from oviposition to adult emergence was 23 ± 1 days. This study provides the basic information about C. luteum that could be utilised for mass rearing of this parasitoid under an augmentative biological control of FAW programme.

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.

Cathepsin B (CTSB) is a cysteine protease that is widely found in eukaryotes and plays a role in insect growth, development, digestion, metamorphosis, and immunity. In the present study, we examined the role of CTSB in response to environmental stresses in Myzus persicae Sulzer (Hemiptera: Aphididae). Six MpCTSB genes, namely MpCTSB-N, MpCTSB-16D1, MpCTSB-3098, MpCTSB-10270, MpCTSB-mp2, and MpCTSB-16, were identified and cloned from M. persicae. The putative proteins encoded by these genes contained three conserved active site residues, i.e. Cys, His, and Asn. A phylogenetic tree analysis revealed that the six MpCTSB proteins of M. persicae were highly homologous to other Hemipteran insects. Real-time polymerase chain reaction revealed that the MpCTSB genes were expressed at different stages of M. persicae and highly expressed in winged adults or first-instar nymphs. The expression of nearly all MpCTSB genes was significantly upregulated under different environmental stresses (38°C, 4°C, and ultraviolet-B). This study shows that MpCTSB plays an important role in the growth and development of M. persicae and its resistance to environmental stress.

The desert locust (Schistocerca gregaria) is a destructive migratory pest, posing great threat to over 60 countries globally. In the backdrop of climate change, the habitat suitability of desert locusts is poised to undergo alterations. Hence, investigating the shifting dynamics of desert locust habitats holds profound significance in ensuring global agricultural resilience and food security. In this study, we combined the maximum entropy modelling and geographic information system technology to conduct a comprehensive analysis of the impact of climate change on the distribution patterns and habitat adaptability of desert locusts. The results indicate that the suitable areas for desert locusts (0.2976 × 108 km2) are concentrated in northern Africa and southwestern Asia, accounting for 19.97% of the total global land area. Key environmental variables affecting the desert locust distribution include temperature annual range, mean temperature of the coldest quarter, average temperature of February, and precipitation of the driest month. Under the SSP1–2.6 and SSP5–8.5 climate scenarios, potential suitable areas for desert locusts are estimated to increase from 2030 (2021–2040) to 2090 (2081–2100). By 2090, highly suitable areas for SSP1–2.6 and SSP5–8.5 are projected to be 0.0606 × 108 and 0.0891 × 108 km2, respectively, reflecting an expansion of 1.84 and 2.77% compared to existing ones. These research findings provide a theoretical basis for adopting prevention and control strategies for desert locusts.

For insects whose larvae are incapable of moving between food resources, the selection of oviposition sites by females is critical to the survival and development of their offspring. In such insects, it is known that females utilise and benefit from conspecific cues for oviposition choice. Studying how information from the behaviour of conspecifics affects egg-laying decision-making is crucial for understanding the biology of insects, which can lead to novel strategies for pest management. We focused on the reproductive behaviour of the Asian long-horned beetle Anoplophora glabripennis, which has become an invasive pest species throughout the world. Here, we show that A. glabripennis avoids sites already containing conspecific cues during egg-laying decision-making. The field survey measuring the distance between neighbouring oviposition scars (in this species, females make scars through the bark of host branches for laying eggs) suggested that the selection of oviposition sites by females is not random. In laboratory oviposition-choice bioassays, females made less oviposition scars on branches containing scars made by other females than those without scars. In addition, female oviposition was also deterred by the presence of their own oviposition scars. Our results indicate that avoiding sites containing conspecific (and their own) traces realises fitness benefit such as reducing resource competition among larvae. This study provides insights into the reproductive behaviour of this invasive longhorn beetle, which is useful for developing environmentally friendly control methods such as oviposition deterrents.

Bombyx mori Tryptophanyl-tRNA synthetase (BmWARS) belongs to the family of Ic-like aminoacyl-tRNA synthetases (aaRSs), whose specific recognition of the substrate Trp, tRNA, maintains the fidelity of protein synthesis. In this study, BmWARS was cloned and characterized from the midgut of the silkworm, Bombyx mori, resulting in an open reading frame (ORF) with a full length of 1,149 bp, which can encode 382 Aa. BmWARS is localized in the cytoplasm, and is expressed in all tissues of the silkworm, with higher expression in the testis, ovary, silk gland and malpighian tubule. The expression of BmWARS was significantly up-regulated in the midgut and silk gland after infection with Bombyx mori nuclear polyhedrosis virus (BmNPV). In addition, overexpression of BmWARS inhibited BmNPV infection and replication extremely significantly, while interference with BmWARS expression promoted BmNPV infection and replication. Analysis of the immune pathways in which BmWARS may be involved revealed that the expression of the key genes of the PI3K-Akt pathway, BmPI3K, BmAkt, BmPDK1, BmeIF4E, BmS6, and p-Akt protein was significantly reduced, whereas the expression of BmPTEN, BmFoxO, and BmCaspase9 was significantly increased in the cells that overexpressed BmWARS and were infected with BmNPV. Meanwhile, the results of the study interfering with the expression of BmWARS were completely opposite to those of the study overexpressing BmWARS. This is the first report that BmWARS has antiviral effects in Bombyx mori. Moreover, BmWARS inhibits BmNPV infection and replication in Bombyx mori cells by promoting apoptosis and inhibiting cell proliferation.

Asexual queen succession (AQS) species produce queens via thelytokous parthenogenesis, which significantly impacts their social life history. For the first time, we discovered that Reticulitermes aculabialis exhibits the phenomenon of parthenogenesis under experimental conditions, and we also investigated the genetic structure of wild colonies of this species using polymorphic microsatellite loci. Our genetic analysis revealed that 93.2% of the secondary queens in the wild colonies were homozygous at all loci, indicating parthenogenesis in these secondary queens, while workers (2.5%), soldiers (0%), nymphs (0%), and alates (6.7%) had low rates. Genetic analysis revealed that the mean number of alleles per group (Na) ranged from 2.000 ± 0.000 to 2.500 ± 0.428, with 83.3% polymorphic loci (PPL). The observed heterozygosity (Ho) varied from 0.467 ± 0.141 to 0.583 ± 0.098, indicating significant genetic diversity among workers and soldiers. In contrast, soldiers and nymph develop predominantly through sexual reproduction than alates and workers. The occurrence of AQS in R. aculabialis suggests a different mechanism of ploidy restoration, highlighting the diversity of reproductive mechanisms across various lineages of the Termitidae and non-Termitidae termites.

Water hyacinth is an invasive aquatic plant that has been associated with major negative economic and ecological impacts in water systems worldwide, including Rwanda, since its establishment in the country in the 1960s. While biological control is considered the most sustainable management method, the success of biocontrol agents depends on various abiotic factors, with temperature being critical. This study assessed the suitability of potential water hyacinth biocontrol agents such as: Neochetina weevils, Megamelus scutellaris Berg (Hemiptera: Delphacidae), and Cornops aquaticum Bruner (Orthoptera: Acrididae) for regions with a temperate climate by testing their thermal boundaries. Using thermal physiology limits and CLIMEX modelling, we found that Neochetina eichhorniae Warner and N. bruchi Hustache (Coleoptera: Curculionidae) had lower thermal minimums (CTmin) of 2.4°C and 2.6°C, respectively, compared to Megamelus scutellaris (4.7°C) and Cornops aquaticum (6.2°C). CLIMEX modelling predicted the suitability of Neochetina weevils and C. aquaticum across Rwanda, while M. scutellaris appeared unsuitable for the colder northern regions of the country but appropriate for the central and eastern regions. These findings suggests that the historical failure of Neochetina weevils introduced to Rwandan water bodies in 2000 was not due to temperature extremes. Rather, other factors such as release numbers or water quality may have played a role. This study provides crucial information for future biocontrol efforts in Rwanda and similar temperate regions, highlighting the importance of pre-release thermal tolerance assessments and climate modelling to predict biocontrol agent establishment and efficacy.

The Asian corn borer, Ostrinia furnacalis (Guenée), emerges as a significant threat to maize cultivation, inflicting substantial damage upon the crops. Particularly, its larval stage represents a critical point characterised by significant economic consequences on maize yield. To manage the infestation of this pest effectively, timely and precise identification of its larval stages is required. Currently, the absence of techniques capable of addressing this urgent need poses a formidable challenge to agricultural practitioners. To mitigate this issue, the current study aims to establish models conducive to the identification of larval stages. Furthermore, this study aims to devise predictive models for estimating larval weights, thereby enhancing the precision and efficacy of pest management strategies. For this, 9 classification and 11 regression models were established using four feature datasets based on the following features geometry, colour, and texture. Effectiveness of the models was determined by comparing metrics such as accuracy, precision, recall, F1-score, coefficient of determination, root mean squared error, mean absolute error, and mean absolute percentage error. Furthermore, Shapley Additive exPlanations analysis was employed to analyse the importance of features. Our results revealed that for instar identification, the DecisionTreeClassifier model exhibited the best performance with an accuracy of 84%. For larval weight, the SupportVectorRegressor model performed best with R2 of 0.9742. Overall, these findings present a novel and accurate approach to identify instar and predict the weight of O. furnacalis larvae, offering valuable insights for the implementation of management strategies against this key pest.

Understanding of predators functional responses is critical in assessing their efficiency as biological control agents. This study investigates the functional responses of three coccinellid predators Scymnus posticalis Sicard (Coleoptera: Coccinellidae), Platynaspis saundersi Crotch (Coleoptera: Coccinellidae), and Pharoscymnus horni Weise (Coleoptera: Coccinellidae) against varying densities of the prey aphid, Myzus persicae (Hemiptera: Aphididae) under controlled conditions (25 ± 1°C temperature, 70 ± 5% relative humidity and 14 L:10D photoperiod). Predation trials across different prey densities were performed with these adult coccinellid predators. Logistic regression analysis confirmed a Type II functional response for all the three species used in the experiments. Among the three, S. posticalis showed a superior predatory efficiency, with the highest attack rate (a) (0.0994 h−1), shortest handling time (Th) (0.5016 h) and a maximum theoretical predation rate (K) of 48.76 aphids. P. saundersi and P. horni showed lower predatory parameters, positioning S. posticalis as the most efficient predator. These findings underscore S. posticalis as a promising candidate for biological control of M. persicae, with a clear advantage in predation metrics over P. saundersi (a = 0.0876 h−1; Th = 0.5193 h; K = 48.27 aphids) and P. horni (a = 0.0695 h−1; Th = 0.5316 h; K = 47.97 aphids). However, further field validation is essential to assess its real-world efficacy, considering environmental variability and complex ecological interactions.

The whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is economically one of the most threatening pests in tomato cultivation, which not only causes direct damage but also transmits many viruses. Breeding whitefly-resistant tomato varieties is a promising and environmentally friendly method to control whitefly populations in the field. Accumulating evidence from tomato and other model systems demonstrates that flavonoids contribute to plant resistance to herbivorous insects. Previously, we found that high flavonoid-producing tomato line deterred whitefly oviposition and settling behaviours, and was more resistant to whiteflies compared to the near-isogenic low flavonoid-producing tomato line. The objective of the current work is to describe in detail different aspects of the interaction between the whitefly and two tomato lines, including biochemical processes involved. Electrical penetration graph recordings showed that high flavonoid-producing tomato reduced whitefly probing and phloem-feeding efficiency. We also studied constitutive and induced plant defence responses and found that whitefly induced stronger reactive oxygen species accumulation through NADPH oxidase in high flavonoid-producing tomato than in low flavonoid-producing tomato. Moreover, whitefly feeding induced the expression of callose synthase genes and resulted in callose deposition in the sieve elements in high flavonoid-producing tomato but not in low flavonoid-producing tomato. As a consequence, whitefly feeding on high flavonoid-producing tomato significantly decreased uptake of phloem and reduced its performance when compared to low flavonoid-producing tomato. These results indicate that high flavonoid-producing tomato provides phloem-based resistance against whitefly infestation and that the breeding of such resistance in new varieties could enhance whitefly management.

Eotetranychus kankitus is an important pest on several agricultural crops, and its resistance to pesticides has promoted the exploration of biological control strategies. Beauveria bassiana and Neoseiulus barkeri have been identified as potential agents for suppressing spider mites. This study aimed to investigate the pathogenicity of B. bassiana on E. kankitus and its compatibility with N. barkeri. Results showed that among the five tested strains of B. bassiana, Bb025 exhibited the highest level of pathogenicity on E. kankitus. Higher application rates (1 × 108 conidia/mL) of Bb025 led to a higher mortality rate of E. kankitus (90.402%), but also resulted in a 15.036% mortality of N. barkeri. Furthermore, preference response tests indicated that both E. kankitus and N. barkeri actively avoided plants sprayed with Bb025 compared to the control group that was sprayed with Tween-80. In a no-choice test, we observed that N. barkeri actively attacked Bb025-treated E. kankitus with no adverse effect on its predatory capacities. Furthermore, N. barkeri laid more eggs when fed on Bb025-treated E. kankitus compared to Tween-80-treated E. kankitus, but the subsequent generation of surviving individuals fed on Bb025-treated E. kankitus was reduced. These findings demonstrate that the Bb025 strain of B. bassiana is highly virulent against E. kankitus while causing less harm to N. barkeri. Consequently, a promising strategy for controlling E. kankitus could involve the sequential utilisation of Bb025 and N. barkeri at appropriate intervals.

Diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae), a globally distributed insect, is a major pest of crucifer crops due to its adaptability to diverse climates. In Argentina, its distribution spans three regions: a core area in the northeast and central-east where it persists year-round, a southwestern region with seasonal migrations, and an intermediate zone with variable year-round persistence. Across these areas, it is the primary pest of Brassica crops. In the central-east, the availability of year-round Brassicaceae crops and wild species indicates that seasonality is not linked to food scarcity. While studies have examined this relationship elsewhere, thermal thresholds vary among populations, and limited data on South American populations highlight the need for localised research. This study evaluated thermal thresholds for P. xylostella populations in central Argentina, focusing on temperature’s effects on fecundity, fertility, development, and survival. We found that temperatures outside the optimal range (15–23°C) significantly reduced survival, with no individuals surviving at 5 or 30°C. Linear and non-linear models accurately described the relationship between temperature and pest development. Using cumulative degree-days, we mapped potential P. xylostella generations across central Argentina. This research provides the first comprehensive analysis of P. xylostella thermal biology in temperate Argentina, emphasising temperature’s critical role in its development. The findings offer valuable insights for climate-specific pest management strategies and enhance understanding of insect population dynamics in agricultural ecosystems, contributing to more sustainable control practices.

Bactrocera dorsalis (Diptera: Tephritidae) is a highly invasive and destructive quarantine pests worldwide. To improved biological control efficiency, reduce chemical pesticides use, and optimise the application of Metarhizium anisopliae (Hypocreales: Clavicipitaceae) against B. dorsalis. This study evaluated the combined toxicity of M. anisopliae with deltamethrin and chlorpyrifos. The biocompatibility of M. anisopliae CQMa421 with these pesticides was assessed based on spore germination, mycelial growth, and sporulation. Additionally, the effects of combined treatments on detoxification enzyme and related gene expression in B. dorsalis were investigated. The results indicated that the virulence effect of M. anisopliae CQMa421 against B. dorsalis adults was time-dependent and dose-dependent. Deltamethrin showed good compatibility with M. anisopliae CQMa421, achieving 100% mortality at 1 × 10⁸ CFU/mL by 84 hours. Different concentrations of deltamethrin can promote the mycelial growth and sporulation of M. anisopliae CQMa421. The toxicity effect of deltamethrin and chlorpyrifos combined with M. anisopliae CQMa421 on B. dorsalis adults was better than that of single-agent treatment, and the co-toxicity factor of 5 mg/L deltamethrin and 1 × 108 CFU/mL M. anisopliae CQMa421 was 24.81, which synergistically affected on B. dorsalis control. Enzyme activity assays and qRT-PCR results revealed that the combination treatment differentially activated and enhanced the activities of AChE, CarE, GST, CAT, and SOD. Meanwhile, BdCarE was significantly inhibited and upregulating BdGSTD7, BdGSTS1, BdCYP4ae1, BdPOD, BdPOD1, and BdCAT genes. In conclusion, the combination of deltamethrin and M. anisopliae CQMa421 enhanced the insecticidal efficacy against B. dorsalis, significantly affected the activity of related detoxification enzymes. Provided a robust basis for integrating biological and chemical control strategies to manage B. dorsalis more effectively.

Sensory neuron membrane protein (SNMP) gene play a crucial role in insect chemosensory systems. However, the role of SNMP in the host searching behaviour of Rhopalosiphum padi (Hemiptera: Aphididae), a highly destructive pest of cereal crops, has not been clearly understood. Our previous research has shown that three wheat volatile organic compounds (VOCs) – (E)-2-hexenol, linalool, and octanal can attract R. padi, but the involvement of SNMP in the aphid’s olfactory response to these wheat VOCs has not to be elucidated. In this study, only one SNMP gene was cloned and characterised from R. padi. The results revealed that the SNMP belongs to the SNMP1 subfamily and was named RpadSNMP1. RpadSNMP11 was predominantly expressed in the antennae of the aphid, with significantly higher expression levels observed in winged forms, indicating that it is involved in olfactory responses of R. padi. RpadSNMP1 expression was significantly up-regulated following starvation, and the expression of this gene showed a decreasing trend after 24 h of aphid feeding. Functional analysis through RpadSNMP1 knockdown demonstrated a significant decrease in R. padi’s ability to search for host plants. The residence time of R. padi injected with dsRpadSNMP1 significantly shortened in response to (E)-2-hexenol, linalool and octanal according to the four-arm olfactometer, indicating the crucial role of RpadSNMP1 in mediating the aphid’s response to these wheat VOCs. Molecular docking suggested potential binding interactions between RpadSNMP1 and three wheat VOCs. Overall, these findings provided evidence for the involvement of RpadSNMP1 in host plant searching and lay a foundation for developing new methods to control this destructive pest.

Rachiplusia nu (Guenée) (Lepidoptera: Noctuidae) is a significant agricultural pest in South America infesting several crops, including soybeans. Bacillus thuringiensis (Berliner) (Bt) soybean, expressing Cry1Ac protein, is widely planted as a control method for numerous lepidopteran pests. However, insect resistance to Bt proteins poses a threat to its sustainability. Recent field reports from Argentina, Uruguay, and Brazil have documented unexpected injury to Bt soybean caused by R. nu populations, which may indicate the development of resistance to Cry1Ac in this species. This study aimed to evaluate the biological performance, reproductive parameters, and reproductive compatibility of two R. nu strains, one susceptible (SS) and the other exhibiting reduced susceptibility to Bt toxin (RR), when reared on Bt and non-Bt soybean. Reproductive compatibility between strains was investigated through parental and hybrid crosses, evaluating fecundity, fertility, and mating success. SS larvae fed with Bt soybean failed to complete their life cycle, whereas RR larvae exhibited higher survival rates. Egg and larval stages of RR larvae were longer when reared on Bt soybean. Pupal mass was lower for Bt-fed resistant strain, although this did not reflect on fecundity and longevity. Results on parental crosses revealed that Bt-fed RR strain displayed reduced mating success, fecundity, and fertility, compared to the non-Bt treatment. Hybrid crosses showed evidence for prezygotic and postzygotic incompatibility. These results suggest a shift in susceptibility of R. nu to Cry1Ac protein and highlight the importance of implementing robust insect resistance management strategies to maintain the effectiveness of Bt crops.

The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a highly destructive polyvorous pest with a wide host range and the ability to feed continuously with seasonal changes. This destructive pest significantly damages crops and can also utilize non-agricultural plants, such as weeds, as alternative hosts. However, the adaptation mechanisms of S. frugiperda when switching between crop and non-crop hosts remain poorly understood, posing challenges for effective monitoring and integrated pest management strategies. Therefore, this study aims to elucidate the adaptability of S. frugiperda to different host plants. Results showed that corn (Zea mays L.) was more suitable for the growth and development of S. frugiperda than wheat (Triticum aestivum L.) and goosegrass (Eleusine indica). Transcriptome analysis identified 699 genes differentially expressed when fed on corn, wheat, and goosegrass. The analysis indicated that the detoxification metabolic pathway may be related to host adaptability. We identified only one SfGSTs2 gene within the GST family and investigated its functional role across different developmental stages and tissues by analysing its spatial and temporal expression patterns. The SfGSTs2 gene expression in the midgut of larvae significantly decreased following RNA interference. Further, the dsRNA-fed larvae exhibited a decreased detoxification ability, higher mortality, and reduced larval weight. The findings highlight the crucial role of SfGSTs2 in host plant adaptation. Evaluating the feeding preferences of S. frugiperda is significant for controlling important agricultural pests.

The Asian corn borer (ACB), Ostrinia furnacalis (Guenée, 1854), is a serious pest of several crops, particularly a destructive pest of maize and other cereals throughout most of Asia, including China, the Philippines, Indonesia, Malaysia, Thailand, Sri Lanka, India, Bangladesh, Japan, Korea, Vietnam, Laos, Myanmar, Afghanistan, Pakistan and Cambodia. It has long been known as a pest in South-east Asia and has invaded other parts of Asia, Solomon Islands, parts of Africa and certain regions of Australia and Russia. Consequently, worldwide efforts have been increased to ensure new control strategies for O. furnacalis management. In this article, we provide a comprehensive review of the ACB covering its (i) distribution (geographic range and seasonal variations), (ii) morphology and ecology (taxonomy, life-history, host plants and economic importance) and (iii) management strategies (which include agroecological approaches, mating disruption, integrated genetic approaches, chemical as well as biological control). Furthermore, we conclude this review with recommendations to provide some suggestions for improving eco-friendly pest management strategies to enhance the sustainable management of ACB in infested areas.