Basilepta melanopus is a pest that severely affects oil tea plants, and the Notch signaling pathway plays a significant role in the early development of insect ovaries. In this study, we explored the function of the notch gene within the Notch signaling pathway in the reproductive system of B. melanopus. The functional domains and expression patterns of Bmnotch were analyzed. Bmnotch contains 45 epidermal growth factor-like (EGF-like) domains, one negative regulatory region, one NODP domain and one repeat-containing domain superfamily. The qPCR reveals heightened expression in early developmental stages and specific tissues like the head and ovaries. The RNA interference (RNAi)-based suppression of notch decreased its expression by 52.1%, exhibiting heightened sensitivity to dsNotch at lower concentrations. Phenotypic and mating experiments have demonstrated that dsNotch significantly impairs ovarian development, leading to reduced mating frequencies and egg production. This decline underscores the Notch pathway’s crucial role in fecundity. The findings advocate for RNAi-based, Notch-targeted pest control as an effective and sustainable strategy for managing B. melanopus populations, signifying a significant advancement in forest pest control endeavors.

Euproctis pseudoconspersa is a devastating pest in Camellia oleifera plantations, necessitating the development of sustainable molecular intervention strategies. This study targeted the chitin synthase A gene (EpCHSA) to evaluate and compare the RNA interference (RNAi) efficacy of dsRNA synthesized via the T7 in vitro transcription system and the Escherichia coli HT115 (DE3) expression system. The EpCHSA gene (2199 bp ORF) was cloned and characterized, exhibiting peak expression during the fourth-instar stage, and predominantly in the head tissues of fifth-instar larvae. Bioassays demonstrated that larvae fed with 500 ng/μL in vitro synthesized dsRNA exhibited continuous gene silencing for five days, reaching a maximum efficiency of 68.1%. Conversely, treatment with 100× concentrated bacterial broth (5000 ng/μL) elicited a superior silencing effect of 79.3% within 24 h. Furthermore, the bacterial treatment group reached a 14-day mortality rate of 46.66%, significantly higher than the in vitro group (38.33%). Both methods induced severe phenotypic abnormalities, including molting failure and pupal malformation. These findings conclude that the E. coli expression system offers a cost-effective and highly potent platform for dsRNA production. This research provides a critical technical foundation and promising application prospects for the field-scale management of E. pseudoconspersa utilizing RNAi-based biopesticides.

Camellia oleifera, commonly known as oil-tea, serves as one of China’s most economically important oil crops. To ensure continued production yield and quality, biological control measures, operating within the framework of integrated pest management, have been extensively adopted nationwide. Integrated pest management facilitates effective management of arthropod pests afflicting C. oleifera by integrating biological control strategies with traditional chemical control methods. This approach significantly reduces the reliance on chemical pesticides and minimizes adverse environmental impacts. Over 600 natural enemy species targeting pests have been documented within the C. oleifera agroecosystems in China including approximately 38 viral agents along with 41 fungal, 166 parasitoid, 336 predator, and several bacterial species. Notably, both insectile natural enemies and fungal biopesticides derived from microbial resources are currently being used at scale in C. oleifera cultivation regions, serving as crucial alternatives to the use of conventional chemical pesticides. This paper comprehensively reviews recent progress in research and the application of synergistic integration of biological control with traditional pest management strategies for C. oleifera. The current status of research on natural enemy resources is analyzed and knowledge gaps in the domain of C. oleifera pest management are identified. Furthermore, future research trajectories are proposed that are intended to provide a scientific basis for the green and sustainable development of the C. oleifera industry.