Entomological Research最新文献

Sustainable approaches to managing poultry waste, such as its use as manure, are urgently required to address emerging concerns under increasing demand for poultry products. Incorporating coffee marc and bentonite as part of the waste processing by Tenebrio molitor (TM) larvae presents effective strategies for addressing these challenges. The present study investigated the capacity of 4th and 6th instar TM larvae to biodegrade poultry manure following treatment with coffee marc or coffee marc and bentonite, based on ammonia (NH₃) contents and physicochemical characteristics of poultry manure. The three treatments adopted in the present study included 2 kg of poultry manure (T1), 1 kg of poultry manure + 1 kg of coffee marc (T2), and 1 kg of poultry manure + 0.9 kg of coffee marc + 0.1 kg of bentonite as a basis of 0.2 kg of 4th or 6th instar TM larvae (T3). The 4th and 6th instar TM larvae had no significant effect on biodegradation capacity. Nevertheless, a significant difference in NH₃ flux occurred during the experiments. In the 4th instar TM larvae treatments, significant differences in pH, total nitrogen (TN), and ADF occurred among all treatments; conversely, in the manure treated with coffee marc and bentonite, 6th instar TM larvae had significant effects on pH, dry matter (DM), TN, ADF, and NDF content compared with only poultry manure. In conclusion, 6th instar TM larvae reared on poultry manure with coffee marc and bentonite could decrease the environmental impact during composting.

The flower bugs, Orius maxidentex Ghauri and Orius minutus (Linnaeus), are important natural enemies of agricultural pests such as thrips and aphids. Insect olfactory systems play an important role in chemical communication, aiding them in locating host or prey habitats. To gain a deeper understanding of the role that sensory organs play in the biological behaviors of these flower bugs, the external structures of antennae and antennal sensilla were demonstrated using scanning electron microscopy (SEM). The antennae of the two species are linear in shape and consist of scape, pedicel, and two flagellomeres. The antennae of O. maxidentex were shorter compared to those of O. minutus. Additionally, the total length of the male antennae was longer than that of the female antennae in both species. Four types and four subtypes of antennal sensilla were documented in both species, including sensilla trichodea (ST I and ST II), sensilla chaetica (SCh I and SCh II), sensilla basiconica (SB), and sensilla campaniformia (SCa). Sexual dimorphism was not observed in the type and distribution of antennal sensilla but existed in the abundance of sensilla basiconica. Our findings provide important insights for future studies on defining the olfactory function of flower bug antennae using electrophysiological methods, especially in the heat-resisting species O. maxidentex.

This study evaluated the insecticidal, repellent, and fumigant activities of four plant-derived extracts: Ficus carica (common fig), Eruca sativa (arugula), Portulaca oleracea (common purslane), and Lupinus albus (white lupin) against adult Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). Gas chromatography–mass spectrometry (GC–MS) analyses identified key bioactive compounds, including unsaturated fatty acids, phytosterols, and tocopherols, which may contribute to their insecticidal and repellent properties. In the residual paper technique, F. carica extract exhibited the highest mortality (22% at 100 mg/mL), followed by E. sativa (14%) and L. albus (6%), while P. oleracea induced only 2% mortality. Repellency bioassays revealed strong deterrent effects, particularly for F. carica and E. sativa. After 3 h, F. carica exhibited 98% repellency at 2 mg/cm², maintaining 66% at 0.5 mg/cm² and 56% at 0.125 mg/cm², indicating broad-spectrum efficacy. E. sativa followed with 64% repellency at 2 mg/cm², sustaining over 50% repellency across all concentrations. Although repellency declined over time, F. carica retained 70% at 2 mg/cm² after 24 h, while E. sativa maintained 64% repellency. In contrast, L. albus and P. oleracea exhibited weaker repellency. These findings highlight the strong repellent effects of F. carica and E. sativa, suggesting their potential as natural alternatives to synthetic insecticides in stored grain pest management. Under fumigation conditions, F. carica, E. sativa, and P. oleracea exhibited minimal insecticidal activity, and L. albus had no measurable effect. These results indicate that the primary potential of F. carica and E. sativa lies in their strong repellency and moderate contact toxicity, rather than fumigation.

Adding black soldier fly (BSF) larvae to animal manure enhances composting and environmental outcomes, producing organic fertilizer. However, the environmental impact of laying hen manure treated with BSF larvae remains poorly understood. This study, therefore, aimed to evaluate the decomposition ability, ammonia production, and proximate composition of laying hen manure at different instar stages of BSF larval treatment. The treatments included (1) 200 g of 2nd instar and (2) 200 g of 3rd instar BSF larvae/2000 g of laying hen manure. BSF larvae had no significant effect on the decomposition ability of laying hen manure during the experimental period. No significant difference in ammonia production was determined between the two groups on days 0 to 10, except on Days 15, 20, 25, and 30, when the differences were statistically significant (p < 0.05). In addition, no significant differences in pH, moisture, TN, CA, or ADF content of laying hen manure were detected between the 2nd and 3rd instar of BSF larvae; however, the NDF content showed significant differences between the two groups (p < 0.05). In terms of environmental impact, the 2nd instar BSF larvae groups increased decomposition ability and proximate composition of laying hen manure or decreased ammonia production compared with the 3rd instar BSF larvae groups. In conclusion, using the 2nd instar of BSF larvae on laying hen manure had a beneficial effect on the environmental impact and enhanced larval development under optimal conditions, which may be associated with pH.

Bactrocera dorsalis (Oriental fruit fly) and Bactrocera zonata (peach fruit fly) are economically important pests of fruits and vegetables. In the current study, the life history traits of B. dorsalis and B. zonata were investigated under cohabitation. The experiment consisted of three treatments: B. dorsalis alone, B. zonata alone, and B. zonata in a shared habitat with B. dorsalis. Data showed that cohabitation had a negative impact on the life history traits of B. dorsalis and a positive impact on the life stages of B. zonata. Significantly more landings, ovipositions, pupal recovery, and adult longevity were observed in co-habited B. zonata, while no difference in these parameters was observed in co-habited B. dorsalis, except for a decrease in adult longevity.

Locusta migratoria eggs use diapause and cold tolerance mechanisms, supporting potential for mass rearing. Long-term cold storage conditions for maintaining egg hatching rates remain understudied. This study aimed to determine optimal cold storage conditions for long-term preservation of L. migratoria egg masses. Eggs were stored at 7.5°C for 1 month starting on Days 1, 3, 6, and 9 after oviposition. The highest hatching rate (96.3%) was observed when storage began on Day 6 after oviposition, and no hatching occurred when initiated on Day 1. Among the temperatures tested (5°C, 7.5°C, 10°C, 12.5°C, and 15°C), 10°C yielded the highest hatching rate at 1 month (74.3%), followed by 7.5°C (69.3%). The lowest hatching rate (26.4%) was recorded at 5°C. Egg masses stored at 7.5°C and 10°C maintained high hatching rates (81.1%–86.9%) over a 10-day observation period, even after 5 months of storage. Regression analysis estimated maximum storage durations for maintaining hatching rates ≥ 90% as 2.8–3.9 months at 7.5°C, 2.3–3.8 months at 10°C, and only 0.6 months at 5°C. Notably, eggs stored at 7.5°C for 4 months beginning on Day 6 after oviposition exhibited a hatching rate > 90%, confirming the condition's suitability for extended preservation. Moreover, prolonged storage was associated with shorter hatching durations, suggesting continued embryonic development during cold storage. Thus, initiating cold storage at 7.5°C–10°C 6-day postoviposition allows effective long-term preservation of L. migratoria egg masses, contributing to the establishment of stable, year-round rearing systems.