Journal of Asia-pacific Entomology最新文献

Diploptera punctata is a viviparous cockroach and secretes a concoction of glycosylated proteins as a basis of nutrition for developing embryos termed as cockroach milk. The milk proteins were identified as the lipocalin-like milk proteins (Lili-Mip) which are present in the brood sac of the gestated female D. punctata. Blotting techniques and RNA transcriptome assays have reported analogous Lili-Mip in the midgut of D. puncta embryos, which proved the ingestion during development inside brood sac. Thermodynamics and kinetic studies augmented the stability of the milk crystals and their controlled release mechanism of sustenance. Gene ontogeny reported the evolution of the ovoviviparous to viviparous due to selective pressures posed during the development stages of the embryos. Molecular simulation modelling studied unveiled the binding efficacies of the milk protein to build strong affiliates to the ligands to form a stable milk protein complex. Ahead of its nutritional benefits, cockroach milk also offers environmental advantages compared to traditional dairy and plant-based milk production. Nevertheless, there are still important hurdles to overcome to include this unconventional superfood as staple in human diets which are also discussed in the review. This review explored the existing molecular, evolutionary and biochemical insights for understanding the phenomena of the production of milk crystals and addressed the research gaps for developing a novel nutrient prospective from insect source.

Blaps rynchopetera Fairmaire is a medicinal insect with a wide range of biological activities. Some of its activities, including anti-cancer and anti-inflammatory activities, are closely related to antioxidant capacity. In this study, a method was established to investigate components and theoretical mechanism of antioxidant from B. rynchopetera. As a result, two antioxidants were obtained by bioassay-guided separation and identified as 4-(2-hydroxyethyl)-1,2-benzenediol and 4-ethylbenzol-1,3-diol. Their EC₅₀ were 20.20 ± 0.30 μM and 22.90 ± 1.30 μM for ABTS·⁺ scavenging, and 153.00 ± 2.00 μM and 301.00 ± 3.00 μM for DPPH· scavenging, respectively. The thermodynamic investigation indicated that the 2-OH of 4-(2-hydroxyethyl)-1,2-benzenediol and the 1-OH of 4-ethylbenzol-1,3-diol were more susceptible to be attacked by free radicals. They tended to exert antioxidant effects via the sequential proton loss electron transfer mechanism in polar media, whereas the hydrogen atom transfer mechanism was more likely to occur in non-polar media. In addition, frontier molecular orbital theory and energy barrier analysis suggested that 4-(2-hydroxyethyl)-1,2-benzenediol was more likely to react with DPPH·. These results confirmed that 4-(2-hydroxyethyl)-1,2-benzenediol had better antioxidant potential.

The red flour beetle (Tribolium castaneum) is a global agricultural grain storage pest that seriously jeopardizes the food safety of wheat, corn, and other grains. Carboxylesterases belong to a family of multifunctional enzymes that can participate in the metabolism of toxic substances ingested by T. castaneum, conferring drug resistance. In this study we have cloned from T. castaneum a gene encoding carboxylesterase, α-EST5, which is expressed mainly in T. castaneum late larvae and late adults. Tissue expression pattern analysis showed that α-EST5 was mainly expressed in the larval gut and adult head. Moreover, α-EST5 was able to be induced to be expressed by mugwort essential oils and significantly increased the enzymatic activity of carboxylesterase in T. castaneum after mugwort essential oil treatment. The sensitivity of T. castaneum to mugwort essential oils was significantly increased after knockdown the expression of α-EST5 using RNAi (RNA interference) technology. Through our study, we demonstrated that the carboxylesterase α-EST5 plays an important role in the detoxification of mugwort essential oils by T. castaneum. This study results provide a reference for understanding the detoxification mechanism of T. castaneum to external toxic substances.

True fruit fly species (Diptera: Tephritidae) threaten the production and international trade of many fruit and vegetable crops. Many fruit fly-free regions operate trapping programs for the detection of these invasive pests, and food baits are an important component of detection trapping. A torula yeast-borax (TYB) solution has been widely used as a food bait, but it has a relatively short field longevity and is generally replaced every 1–2 weeks. Dry synthetic food-based attractants, consisting of ammonium acetate, putrescine, and trimethylamine, have been developed and appear to be effective for several months. Initially, the three components were presented in individual sachets within a trap, but to ease handling ‘all-in-one’ dispensers have been developed that contain all three components. While a logistical improvement, there are few data that compare captures between the standard TYB solution and these combination dispensers. This study presents the results of field experiments assessing the relative effectiveness of three ‘all-in-one’ dispensers of synthetic food-based attractants (i.e., Scentry food cones, Suterra Unipaks, and Susbin Difusors) in trapping three major pest species of tephritid fruit flies in Hawaii. The data presented here indicate that, with respect to C. capitata, the Difusor lures performed as well as TYB, while the Unipaks and food cones were significantly less attractive than TYB. With respect to B. dorsalis and Z. cucurbitae, none of the synthetic baits tested was as effective as TYB. Thus, among the baits studied here, TYB was most effective in attracting all three of the target species.

The nutrient profile of the mulberry silkworm pupae as a food source has attracted attention because of the rising insect consumption in Western and Asian nations. With 2.5 billion more people and a 70% increase in food consumption by 2050, crop yields will become insufficient to cater to the needs. To overcome this obstacle, insects offer a nourishing solution because of their environmental responsibility, sustainability, and nutrient worth. Delving into the vast potential of mulberry silkworm pupae, this comprehensive review sheds light on their versatility as a valuable resource beyond their use in silk production. Rooted in a longstanding tradition of sericulture, these pupae hold promise in various fields such as agriculture, medicine, and nutrition. From serving as a protein-rich feed for livestock and a natural fertilizer to providing an abundant source of medicinal compounds, current research highlights their diverse capabilities. However, amidst the growing interest, there remains a dearth of consolidated information. This study aims to bridge this gap with an all-encompassing review, identifying areas for further research, and advocating for their integration into sustainable practices. Our goal is to direct future research, inform policymakers, and promote the utilization of mulberry silkworm pupae as a sustainable resource in various industries.

Climate change can negatively impact bumblebee populations, which are crucial pollinators in agricultural systems and natural ecosystems. Bumblebee nest temperatures typically range from 27 to 32 °C, and workers engage in wing fanning to maintain a nest temperature below 32 °C. We investigated the gene expression profile in queen, worker, and male bumblebees (Bombus terrestris) at 27 °C, which is the optimal ambient temperature, and 32 °C, which is the upper-temperature limit requiring wing fanning. We found that a developmental temperature of 32 °C significantly increased the expression of genes related to growth, immune response, antioxidants, and chaperones in workers. Compared to workers reared at 27 °C, those reared at 32 °C exhibited a significant increase in reactive oxygen species (ROS) and iron concentrations in the hemolymph. Additionally, the gene expression of superoxide dismutase (SOD) and transferrin (Tf) was significantly increased in workers at 32 °C. These findings indicate that a developmental temperature of 32 °C in bumblebees, especially workers, leads to an increase in gene expression, including SOD and TF, in response to thermal stress.

The Indian meal moth, Plodia interpunctella Hübner (Lep.: Pyralidae), is a significant global pest of stored products, particularly in temperate regions. This study investigated the impact of various temperatures (25, 50, 55, and 60 °C) over different durations (5, 10, 15 and 20 min) on the mortality and cuticle layer of third instar P. interpunctella larvae. Hexane solvent separated the cuticle layer of 3rd instar larvae treated at critical temperatures; Bis (trimethylsilyl) acetamide and Trimethylsilyl chloride were added for derivatization before injection into the GC–MS. Additionally, SEM imaging was used to observe the epicuticle surface of treated larvae under critical temperatures. The findings showed a direct relationship between increasing temperatures and the mortality rate of 3rd instar larvae, with complete mortality occurring in 20 min at 50 °C, in 15 min at 55 °C, and in just 10 min at 60 °C. Moreover, with an increase in temperature and exposure time, the weight of the larvae decreased significantly. GC–MS analysis unveiled that the waxy layer contained sixteen fatty acids within P. interpunctella cuticles; it was observed that as temperatures increased, there was a significant reduction in fatty acid levels. SEM imaging also revealed that rising temperatures led to a dramatic decrease in cohesion within the epicuticle layer; altering its physical and chemical structure caused dehydration, ultimately leading to death. These results suggest that utilizing critical temperatures for short durations can effectively control P. interpunctella populations.

The soybean pod borer, Leguminivora glycinivorella (Matsumura), is an important soybean pest that reduces both quality and yield in Asia, and chemical control is used irrespective of the damage risk. The pest population density increases at continuously cropped soybean fields (hereafter, source habitat). The present study would contribute to proposing pest management options matched to the damage risk by clarifying the surrounding landscape structures where damage is likely to increase. First, we clarified the relationship between the probability of grain damage and the source habitat within a 350 m radius of the new or continuously cropped soybean fields. The habitat area surrounding continuous soybean fields positively influenced the probability of grain damage but did not detect a significant effect in new soybean fields. Secondly, we clarified the relationship between the probability of grain damage and habitat connectivity in continuous soybean fields. Well-managed fields with high connectivity consistently showed low damage risk. Meanwhile, damage risk varied in fields with low connectivity, indicating that damage is unlikely to occur because soybean pod borers are difficult to invade. However, once invaded, the damage could be extensive. Considering these results, one possible new control system will allow the spatiotemporal variation in the number of insecticide applications. The present study likely contributes to understanding the relationship between soybean pod borer injury and landscape structure, which is important for area-wide pest management.

Experiment on trapping non-target arthropods in conventional delta traps baited with Ceratitis capitata (Wiedemann, 1824) female attractant was undertaken in multi-variety peaches orchards in the north East of Tunisia during the cultivation season (from May 2022 to September 2022). Hence, 24 Delta traps having white sticky panels were placed in the experimental site and inspected generally at weekly interval. Captured insects were determined to family level visually using a manual magnifying glass when possible, or gently removed and identified in the laboratory under binocular microscope either on family or species levels. Results indicated that traps attracted very low number of non-target arthropods compared to Mediterranean fruit fly adults. Collected species belonged to families: Apidae, Halictidae, Colletidae, Megachilidae, Braconidae, Ichneumonidae, Scelionidae, Pteromalidae, Torymidae, Chalcididae, Eucoilidae, Syrphidae, Pompilidae, Crabronidae, Coccinellidae, Chrysopidae and Formicidae. In total, more than 700 adults of Chrysoperla carnea (Stephens, 1836) were attracted and 53 % of captured individuals are parasitic wasp species belonging particularly to Pteromalidae and Scelionidae families. Compared to the highest level of MedFly capture, the effect of delta traps baited with the female attractants on beneficials can be considered as insignificant (Kruskal-Wallis test ANOVA H = 35.6947, P < 0.00001). Hence, trapping grid can be used to monitor the population of MedFly without hazardous effects on beneficial insect fauna.

Metisa plana is one of the main oil palm leaf defoliators in Malaysia. Infestation of M. plana at the oil palm plantation caused severe yield loss in the past. Many control methods have been introduced to combat the infestation, but the problem persists till today. More information regarding the bagworm is needed to understand the pest-host interaction so that an effective control method can be properly designed. This study was carried out to predict the repertoire of effector proteins secreted by M. plana that could potentially suppress the host defence mechanisms. In silico screening of the secretory proteins from predicted genes was done by using several tools namely SignalP, TMHMM, TargetP and WOLFPSORT. Then, the acquired dataset was subjected to functional annotation through a similarity search against UniProt-Trembl database, gene ontology (GO) using BLAST2GO, InterPro protein domain classification, cluster of orthologous groups (COG), and KEGG pathway prediction. To determine the expression of the predicted genes, TPM value was calculated using the available transcriptomic dataset of M. plana. We identified a total of 948 secretory proteins from the initial screening of the 28,738 proteins predicted from BRAKER2 pipeline. Several proteins were classified as specific protein classes associated with effector functions in insect pests, namely detoxifying enzymes, lipases, peroxidases, Ca²⁺ binding proteins, and chemosensory and odorant binding proteins. This predicted effector data can be used as a reference for future works in validating the protein’s interaction and mechanisms with the oil palm defence responses.