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Simple Summary: This study investigates the effectiveness of a novel genetics-based biopesticide, miR-184 agomir, against the English grain aphid, Sitobion avenae, a major wheat pest. miR-184 agomir interference significantly reduced aphid survival rates, particularly during their early developmental stages. Life table analysis demonstrated that the application of miR-184 agomir resulted in adverse effects on multiple vital parameters essential for the expansion of the aphid population. Population projection models predicted a substantial decline in the aphid population size at 60 days post-treatment. These findings underscore the potential of genetics-based biopesticides in the effective management of grain aphid populations, thereby contributing to wheat crop protection and environmental sustainability. The investigation of genetics-based biopesticides has become a central focus in pesticide studies due to their inherent advantages, including species specificity, environmental safety, and a wide range of target genes. In this study, a mixture of miR-184 agomir and nanomaterial star polycation (SPc) was used to treat the nymphs of the English grain aphid, Sitobion avenae (F.). The life parameters of the aphids at various developmental stages were analyzed using an age–stage two-sex life table to assess the effect of miR-184 agomir on the experimental population. The results indicated that miR-184 agomir had a significant negative effect on four key life parameters, including the intrinsic rate of increase, the finite rate of increase, the net rate of increase, and the mean generation time. The population prediction revealed a substantial reduction (91.81% and 95.88%) in the population size of S. avenae at 60 d after treatment with miR-184 agomir, compared to the control groups. Our findings suggest that the miR-184 agomir has the potential to reduce the survival rate and mean longevity of S. avenae, highlighting its potential as a promising candidate for the development of an effective genetics-based biopesticide. [ABSTRACT FROM AUTHOR]

Simple Summary: Tuta absoluta (Meyrick) is an invasive insect pest that poses a threat to solanaceous crops. In recent years, the occurrences of extremely high temperature have been increasing due to climate change. Therefore, it is important to study the effect of high temperature on the growth and development of T. absoluta. In this study, when the eggs, pupae, and adults of T. absoluta were exposed to high-temperature stress, the pupal stage exhibited the highest sensitivity. This was demonstrated by a significant decrease in emergence rate, longevity, and fecundity. High-temperature stress during the egg stage resulted in a cascading effect, leading to a reduction in the adult longevity. This study provides a new insight for the integrated management of T. absoluta under high temperature. Insect life processes and reproductive behaviors are significantly affected by extremely high temperatures. This study focused on Tuta absoluta, which poses a severe threat to tomato cultivars. The effects of intense heat stress on the growth, development, oviposition, and longevity of T. absoluta were investigated. This investigation encompassed various developmental stages, including eggs, pupae, and adults. This study revealed that egg hatching and pupa emergence rates were significantly reduced at a temperature of 44 °C maintained for 6 h. The longevity of adults that emerged after the egg and pupal stages were exposed to 44 °C for 6 h was significantly reduced compared to the control. Notably, there was no significant variation in adult fecundity after egg-stage exposure to high temperatures. However, all treatments exhibited significantly reduced fecundity compared to the control after exposure to high temperatures during the pupal stage. Adult survival rates after exposure to 40 °C and 44 °C for 3 h were 74.29% and 22.40%, respectively, dramatically less than that of the control, which was 100%. However, no significant differences were noted in terms of longevity and egg production. These results offer a better understanding of the complex interactions between extreme temperatures and the life history traits of T. absoluta, thereby offering valuable insights for implementing management strategies to alleviate its impact on tomato crops in response to climate change. [ABSTRACT FROM AUTHOR]

Simple Summary: The insect epidermis covers multiple parts of the insect body, fulfilling both structural and protective roles. Primarily composed of chitin and epidermal proteins, the insect epidermis displays considerable diversity among insects. The CPR family, the largest and most diverse group of cuticular protein (CP) genes identified to date, plays crucial roles in insect development, including body length regulation and cuticle formation. Steroid hormones, such as ecdysteroids, regulate the expression of epidermal proteins. In addition, the insecticide Methoxyfenozide mimics the action of 20E, thereby affecting insect growth. Our study on Heortia vitessoides Moore elucidates the role of HvCP3L and offers novel insights into pest management strategies for Aquilaria sinensis (Lour.) Spreng. Cuticle proteins (CPs) constitute a multifunctional family; however, the physiological role of Cuticle Protein 3-like (CP3L) in Heortia vitessoides Moore remains largely unclear. In this study, we cloned the HvCP3L gene from the transcriptional library of Heortia vitessoides Moore. RT-qPCR results revealed that HvCP3L exhibited high expression levels during the larval stage of Heortia vitessoides Moore, particularly at the L5D1 stage, observed in both larval and adult heads. Through RNA interference, we successfully silenced the HvCP3L gene, resulting in a significant reduction in the survival rate of Heortia vitessoides Moore, with the survival rate from larvae to adults plummeting to a mere 17.7%, accompanied by phenotypic abnormalities. Additionally, we observed that the knockdown of HvCP3L led to the inhibition of genes in the chitin pathway. Following exposure to methoxyfenozide stress, the HvCP3L gene exhibited significant overexpression, coinciding with phenotypic abnormalities. These findings underscore the pivotal role of HvCP3L in the growth and development of Heortia vitessoides Moore. [ABSTRACT FROM AUTHOR]

Simple Summary: The present study investigated the effects of different temperatures (15, 20, 25, 30, and 35 °C) on the growth and development of Habrobracon hebetor Say (Hymenoptera: Braconidae) on Ephestia elutella (Hübner) (Lepidoptera: Pyralidae) larvae. Habrobracon hebetor could complete growth and development when E. elutella larvae were used as hosts, and the developmental duration decreased with increasing temperature at 15, 20, 25, 30, and 35 °C. Taking into account factors such as the total number of eggs laid, egg hatchability, the number of emerged adults, emergence ratio, percentage of female offspring, innate rate of increase, and net reproductive rate, the optimal temperature for rearing of H. hebetor is 30 °C. Augmentative release of parasitoids has been an important component of integrated insect management for stored product protection. Understanding the effect of different temperatures on the growth and development of parasitoids is in favor of mass rearing of parasitoids. Habrobracon hebetor Say (Hymenoptera: Braconidae) is a highly cosmopolitan, gregarious ecto-parasitoid of a variety of Lepidopterous larvae. Thus, the growth and development of H. hebetor reared on Ephestia elutella (Hübner) (Lepidoptera: Pyralidae) larvae were investigated at 15, 20, 25, 30, and 35 °C. Habrobracon hebetor could complete growth and development, and the developmental duration decreased with increasing temperature at 15, 20, 25, 30, and 35 °C. The development threshold temperatures of H. hebetor eggs, larvae, pupae, and egg-to-adult stages were 13.89, 6.39, 9.24, and 9.29 °C, and the effective accumulated temperatures were 23.33, 46.40, 142.68, and 240.31 °C·d, respectively. The total number of eggs laid by H. hebetor, the hatching rate of H. hebetor eggs, and the percentage of female offspring reached the maximum of 192.39, 83.89%, and 74.04% at 30 °C, respectively. There was no significant difference in pupal survival rate in the temperature range of 15 °C to 35 °C. At 30 °C, the pre-oviposition duration of H. hebetor was the shortest (0.87 d). Therefore, the optimal rearing temperature of H. hebetor was 30 °C. The present results are useful for the large-scale rearing of H. hebetor using E. elutella larvae as hosts and effectively implementing the biological control of stored-product insects. [ABSTRACT FROM AUTHOR]