Search Results (43)

Background/Objectives: Optimal reference genes for normalizing RT-qPCR data depend on the species, treatments, developmental stages, and other conditions. Pastor roseus is a long-distance migratory bird with potential applications in locust biological control. This study applied reverse transcription quantitative PCR (RT-qPCR) to evaluate the expression stability of six genes (RPS2, ACTB, B2M, SDHA, UBE2G2, and RPL4) in blood samples from female, male, and nestling P. roseus. Methods: An integrated analysis of the expression stability of six reference genes was performed using three statistical algorithms: GeNorm, BestKeeper, and NormFinder. Results: The results showed that SDHA, ACTB, and B2M exhibited the highest expression stability among the candidate reference genes. The optimal number of reference genes was two, as determined by a pairwise variation analysis using GeNorm. Subsequent comprehensive validation using RefFinder identified SDHA/ACTB as the optimal reference gene pair for normalizing gene expression data for P. roseus. Conclusions: These findings establish a robust foundation for ensuring data accuracy in functional genomic studies of P. roseus. Full article

The migratory locust (Locusta migratoria), is a destructive pest in agriculture and ecological conservation, characterized by its unique phase polyphenism (phase change). Parthenogenesis, defined as oviparous reproduction without fertilization, has been studied less extensively than fertilized reproduction, with particularly scarce research on parthenogenesis in migratory locust. This study investigates the relationship between parthenogenesis and the phase change in migratory locusts. Through comparative studies between two phases, we found that solitary locusts exhibit a higher parthenogenesis capacity compared to gregarious locusts, as evidenced by greater total oviposition quantity and higher hatching rates. However, parthenogenesis resulted in significantly lower hatching rates compared to sexually fertilized females, with distinct differences in oviposition dynamics and hatching patterns. Furthermore, we observed that gregarious locusts, when isolated after eclosion, exhibited increased parthenogenetic capacity, depending on their juvenile density. Together, this study provides insights into the understanding of insect parthenogenesis and lays basis for the potential underlying mechanism. Full article

Fermentation, a traditional method for enhancing nutritional value and functionality, has significant potential for improving the quality, safety and acceptability of farmed insect products. In this study, yellow mealworm, house cricket and migratory locust were fermented using Lactobacillus plantarum and a commercial starter culture for 48 h. Samples were analyzed for proximate composition, amino and fatty acid profiles, elemental composition and oxidation stability. Fermentation reduced total dietary fiber in yellow mealworm (33%) and house cricket (12%), and increased non-protein nitrogen (38% and 16%), while total and protein nitrogen remained unaffected. Fatty acid profiles also remained unchanged, whereas the amino acid composition varied depending on the species and fermentation culture. Essential mineral concentrations varied depending on species and fermentation culture Fe (19–23%), K (25%), Mg (12–23%), Mn (36–378%), Na (20–49%) and P (22%) increased, levels of Se (15%), and Cu (16%) decreased, while Zn levels showed inconsistent trends among treatments. Oxidation stability of yellow mealworm (41–42%) and migratory locust (21–29%) decreased, but improved for house cricket (153–167%). Overall, fermentation enhanced the nutritional value of edible insects, although the extent of improvement varied by species and fermentation culture. Full article

The utilization of insects as a source of essential nutrients holds considerable promise, with the potential to serve as both feed and food. Consequently, there is a necessity to develop control systems, as the undeclared addition of insects to food products and/or non-compliance with labelling regulations may pose health risks and result in financial losses for consumers. This review describes methods for identifying and detecting insect species by targeting biomolecules such as DNA, proteins, saccharides, and metabolites, with a particular focus on DNA-based approaches. This review provides a detailed overview of the application of polymerase chain reaction (PCR) and DNA sequencing methods that are suitable for the analysis of edible and forage insects. The main focus is on identifying species that are approved for use as novel foods or insect feeds within the European Union (e.g., house cricket (Acheta domesticus), common mealworm (Tenebrio molitor), migratory locust (Locusta migratoria), lesser mealworm (Alphitobius diaperinus), black soldier fly (Hermetia illucens), banded cricket (Gryllodes sigillatus), field cricket (Gryllus assimilis), silkworm (Bombyx mori)). However, insect species of global relevance are also discussed. The suitability of DNA analysis methods for accurate species identification, detection of (un)labeled contaminants, and monitoring of genetic diversity has been demonstrated. Full article

Insects are among the most diverse and abundant organisms on Earth, and their population dynamics are strongly influenced by entomopathogenic fungi. This study examines the role of carbon and nitrogen metabolism in the virulence of the entomopathogenic fungus Metarhizium rileyi against the migratory locust, Locusta migratoria. The findings demonstrate that the capacity of M. rileyi to utilize different carbon and nitrogen sources is a key factor in its virulence. Specifically, two strains of M. rileyi (PPDB201006 and SZCY201010) exhibited distinct metabolic abilities, with PPDB201006 displaying superior growth and enzyme activities on various carbon and nitrogen sources compared to SZCY201010. These metabolic differences were associated with significant variations in virulence, as PPDB201006 induced higher mortality rates in L. migratoria than SZCY201010. Metabolomics analysis revealed that infection by M. rileyi led to substantial alterations in the hemolymph metabolites of L. migratoria, particularly in organic acids, amino acids, sugars, and lipids. These results emphasize the significance of carbon and nitrogen metabolism in the pathogenicity of entomopathogenic fungi and offer new perspectives for optimizing their application as biological control agents. This study not only improves our understanding of fungal virulence mechanisms but also contributes to the development of more effective and sustainable pest management strategies. Full article

Yunnan is located on the southwest border of China, with a complex geographical environment and rich biodiversity, which is the first stop for many migratory pests to enter China. In recent years, Ceracris kiangsu has migrated into China through the China–Laos border line. The migratory C. kiangsu has shown typical characteristics of migratory locusts, which has seriously jeopardized the ecological security, biosecurity and food security of China. In order to prevent and control C. kiangsu from the source as soon as possible, this study used hotspot analysis and trajectory analysis to clarify the migration dynamics, source regions and migration corridors of C. kiangsu. The results showed that the migratory C. kiangsu was mainly distributed in the towns of Jiangcheng County, and the source regions were concentrated in Phongsaly, Laos. There are three cross-border migration corridors of C. kiangsu, among which the Laos–Niuluohe border migration corridor running through the entire migration cycle is the most important corridor. The study answered three key questions about the prevention and control of C. kiangsu. Ascertaining when C. kiangsu arrived at Yunnan, where it came from, and where the population then went will greatly improve the efficiency of the prevention and control of C. kiangsu as well as provide a theoretical basis for subsequent monitoring and early warning. Full article

This study employed an integrated approach combining multi-source remote sensing data and the MaxEnt model to systematically assess the ecological niche characteristics of the oriental migratory locust (Locusta migratoria manilensis) in Hainan Island, while projecting the evolution of its suitable habitats under both historical and future climate scenarios (up to 2040). Firstly, we synthesized traditional climate, soil, and topography data with remote sensing data to characterize the suitable areas of the oriental migratory locust based on MaxEnt model (with high accuracy of AUC = 0.935 and TSS = 0.76). Subsequently, six dominant environmental variables—precipitation in April (PRE04), precipitation in September (PRE09), maximum temperature in August (TMAX08), minimum temperature in December (TMIN12), NDVI in February (NDVI02), and NDVI in May (NDVI02)—were identified as key predictors. Their threshold values were determined, with PRE04, PRE09, TMAX08, and TMIN12 ranging from 39 to 44 mm, 196 to 223 mm, 31.1 to 32.2 °C, and 17.7 to 18.0 °C in high-suitability zones, respectively. Finally, these six predictors were used to assess habitat suitability across Hainan Island for both the 2001–2020 and 2021–2040 periods. Under historical climate conditions, highly suitable areas (505 km², 1.41% of total land area) were concentrated in the western and northeastern regions, particularly in Dongfang City (46.27%), Ledong Li Autonomous County (32.91%), and Changjiang Li Autonomous County (18.39%). Future projections indicate significant habitat expansion, with total suitable areas increasing by 13.4–42.0% and highly suitable areas reaching 571–831 km² by 2040. The study highlights the critical Dongfang–Danzhou–Ledong region for targeted locust control, providing scientific support for pest management in tropical island ecosystems under climate change. Full article

Essential amino acids and essential fatty acids are vital nutrients that must be obtained from the diet. However, traditional sources face limitations amid increasing global food security and sustainability challenges. This study aims to evaluate the nutritional potential of novel foods, including microalgae (e.g., spirulina and chlorella), fungi (e.g., oyster and shiitake mushrooms), edible insects (e.g., mealworms and migratory locusts), and unconventional plants (e.g., water lentils and canihua). The study will compare their amino acid and fatty acid profiles with those of conventional animal and plant sources. The comparative analysis conducted in this study reveals that these innovative foods offer balanced and high-quality protein and lipid profiles, and contribute essential nutrients needed to prevent deficiencies and support metabolic health. Significantly, the integration of these novel foods into established dietary patterns, such as the Mediterranean diet, has the potential to enhance nutritional quality while promoting environmental sustainability. In conclusion, the adoption of these innovative food sources provides a viable strategy to meet nutritional demands and address global health and ecological challenges, paving the way toward a more resilient and sustainable food system. Full article

The scientific interest in edible insects as an alternative source of high-value protein for the human diet has increased drastically over the last decade. Edible insects harbour enormous potential in terms of planetary health. Their lower water and land use, lower feed conversion ratios, and overall lower global warming potential paired with a high nutritional value compared with conventional livestock are key drivers towards an environmentally sustainable diet. However, low consumer acceptance, as well as regulatory challenges, have slowed down the success of edible insects in Western countries, despite edible insects being consumed regularly all over the world. To date, four edible insect species have been approved as novel foods in the European Union—namely yellow mealworm (Tenebrio molitor), migratory locust (Locusta migratoria), house cricket (Acheta domesticus), and lesser mealworm (Alphitobius diaperinus). Depending on the species, they have a high protein content (48–67%), with a beneficial indispensable amino acid profile, high fat content (21–39%), with a high content of unsaturated fatty acids based on the dry matter, and contain reasonable amounts of minerals and vitamins. Unlike other animal-based foods, edible insects contain dietary fibre. Data on the bioavailability of nutrients in humans are scarce. Although numerous publications have investigated the nutritional profiles, environmental impacts, and future perspectives of edible insects, here, those findings are reviewed critically, as some publications were partially contradictory or related to selected species only. In this narrative review, we emphasise that edible insects could play a key role in a changing world with a steadily increasing demand for nutritionally valuable food and the depletion of natural resources. Full article

The consumption of edible insects is a promising approach to meet the increasing global demand for food. Commercialization of edible insects in the EU is regulated by the Novel Food regulation. To date, the yellow mealworm (Tenebrio molitor larva), the migratory locust (Locusta migratoria), the house cricket (Acheta domesticus), and the buffalo worm (Alphitobius diaperinus larva) have been authorized in the EU for human consumption. We aimed to develop a method based on DNA barcoding and high-resolution melting (HRM) analysis for the identification and differentiation of these four EU-authorized edible insect species in food. A primer pair previously designed for DNA metabarcoding, targeting a ~200 bp sequence of mitochondrial 16S rDNA, allowed discrimination between the four insect species in highly processed food. However, house cricket and migratory locust could not unambiguously be differentiated from tropical house cricket, desert locust, superworm, cowpea weevil, and sago worm, respectively. This problem could be solved by designing primers specific for house cricket and migratory locust. By combining these primers with the insect primers, additional polymerase chain reaction (PCR) products for house cricket and migratory locust were obtained, resulting in more complex melt curves compared to the unauthorized insect species. The optimized PCR-HRM assay is a very cost-efficient screening tool for authentication of EU-authorized edible insect species in food. Full article

In the context of globalization, cross-cultural studies have become increasingly important for understanding differences in consumer acceptance of various foods. This study examines and compares the acceptance of insect-based foods between consumers in Greece and Ireland, two EU countries where insect-based foods are not widely available. An online survey was distributed in both countries and responses from 489 participants (Greece: n = 283; Ireland: n = 206) were analysed, using non-parametric tests for the quantitative data, and a combination of thematic and content analysis for the qualitative data. Overall, the Mann–Whitney U test showed that participants from Greece were significantly less willing to consume insect-based foods than those in Ireland. Among EU-approved insects, the Friedman test showed that participants in Ireland significantly preferred yellow mealworms over house crickets and migratory locusts, whereas participants in Greece showed no significant preference among these species. Both groups were more willing to consume insect-based foods when the insects were not visible, while they differed in their preference of inclusion percentage of insect protein in foods. However, no differences were found in the willingness to consume different types of non-visible insect products. The Mann–Whitney U test showed that participants in Ireland could be more influenced to consume insect-based foods by external factors, with live demonstrations by chefs being the most influential. However, family members would be the most influencing factor for those from Greece. Nuances in participants’ willingness to buy insect-based foods are presented and discussed. These findings could inform strategies aimed at increasing the acceptance of insects as food among consumers in European countries with limited exposure to such products. Full article

The entomopathogenic fungus (EPF) Metarhizium acridum is a typical filamentous fungus and has been used to control migratory locusts (Locusta migratoria manilensis). This study examines the impact of the Zn(II)2Cys6 transcription factor, MaAzaR, in the virulence of M. acridum. Disruption of MaAzaR (ΔMaAzaR) diminished the fungus’s ability to penetrate the insect cuticle, thereby decreasing its virulence. The median lethal time (LT₅₀) for the ΔMaAzaR strain increased by approximately 1.5 d compared to the wild-type (WT) strain when topically inoculated, simulating natural infection conditions. ΔMaAzaR compromises the formation, turgor pressure, and secretion of extracellular hydrolytic enzymes in appressoria. However, the growth ability of ΔMaAzaR within the hemolymph is not impaired; in fact, it grows better than the WT strain. Moreover, RNA-sequencing (RNA-Seq) analysis of ΔMaAzaR and WT strains grown for 20 h on locust hindwings revealed 87 upregulated and 37 downregulated differentially expressed genes (DEGs) in the mutant strain. Pathogen–host interaction database (PHI) analysis showed that about 40% of the total DEGs were associated with virulence, suggesting that MaAzaR is a crucial transcription factor that directly regulates the expression of downstream genes. This study identifies a new transcription factor involved in EPF cuticle penetration, providing theoretical support and genetic resources for the developing highly virulent strains. Full article

The desert locust, Schistocerca gregaria (Forsk., 1775), stands as one of the most pervasive pests globally, inflicting extensive damage across Asia and Africa. Facilitated by intercontinental migration, the desert locust engages in population exchange between different source areas, perpetuating its widespread proliferation. Despite the wind being recognized as a key factor during migration events, elucidating its precise influence on intercontinental migration has remained elusive. In this study, we scrutinized monitoring data sourced from the FAO monitoring system, pinpointing 13 desert locust events featuring intercontinental migrations since 1967. From these events, four migration routes were summarized, traversing the Red Sea (RS-WE and RS-EW) and the northern Indian Ocean (IO-WE and IO-EW). Typically, RS-WE and IO-EW migrations occurred between December and March, whereas RS-EW and IO-WE migrations were observed from May to June and April to July, respectively. Our examination of wind field data spanning the past 15 years revealed that wind direction and speed facilitated intercontinental migrations. Furthermore, migration trajectory modeling indicated that desert locusts might exhibit migratory behavior both during the day and at night in the cases of RS-WE and RS-EW, with cross-oceanic migration potentially lasting for a week for IO-WE and IO-EW. In summary, our study identifies four migration routes for the intercontinental migration of the desert locust, providing crucial support for the scientific prediction of its occurrence and contributing to international food security efforts. Full article

Insect development is intricately governed by hormonal signaling pathways, yet the pivotal upstream regulator that potentiates hormone activation remains largely elusive. The migratory locust, Locusta migratoria, exhibits population density-dependent phenotypic plasticity, encompassing traits such as flight capability, body coloration, and behavior. In this study, we elucidated a negative correlation between population density and ontogenetic development during the nymphal stage of locusts. We found that the level of density influences the developmental trajectory by modulating transcript abundance within the ecdysone signaling pathway, with knockdown of the prothoracicotropic hormone (PTTH) resulting in developmental delay. Transcriptomic analysis of locust brains across solitary and gregarious phases revealed significant differential expression of genes involved in various pathways, including protein synthesis, energy metabolism, hormonal regulation, and immunity. Notably, knockdown experiments targeting two energy regulators, adipokinetic hormone (AKH) and insulin-like polypeptide 1 (ilp1), failed to elicit changes in the developmental process in solitary locusts. However, knockdown of immunoglobulin (IG) significantly shortened the developmental time in higher-density populations. Collectively, our findings underscore the regulatory role of population density in determining developmental duration and suggest that an immune-related gene contributes to the observed differences in developmental patterns. Full article

Mealworm, migratory locust, and house cricket have recently been recognized by the European Commission as novel foods, thus being suitable in different food applications. In this work, we tested their powders as meat extenders at 5% (w/w) inclusion in beef burgers, considering their ability to vehicle phenolic compounds during simulated in vitro static gastrointestinal digestion (INFOGEST). Insect powders were abundant in different phenolic classes, recording the highest values in locust (LP; 314.69 mg/kg), followed by cricket (CP; 113.3 mg/kg) and mealworm (MWP; 51.9 mg/kg). Following a pan-cooking process, LP burgers were confirmed as the best source of phenolics, with a marked abundance of flavonoids and phenolic acids. Interestingly, the insect powders were found to affect the in vitro gastrointestinal bioaccessibility of phenolic compounds when compared with the CTR burger, likely promoted by the interactions between the phenolic compounds and proteins characterizing the tested insect powders. Among the most discriminant phenolic metabolites at the gastrointestinal level, we found several phenolic acids (mainly hydroxycinnamics), recording the highest content for the digested CP-containing burgers. Finally, stilbenes showed significant correlation values at the intestinal level with both antioxidant and enzymatic activities, while total flavonoids were the most correlated with the inhibition of acetylcholinesterase. Taken together, our preliminary findings demonstrated that insect powders added to beef burgers can promote the bioaccessibility and potential bioavailability of phenolics in the distal tracts of the intestine. Full article