Piercing-sucking insects are a significant threat to global crop production, causing direct damage and transmitting pathogens. Conventional strategies like broad-spectrum insecticides face challenges such as pest resistance and environmental sustainability. Salivary proteins secreted during feeding are vital molecular effectors in mediating plant-insect interactions. Understanding their diverse functions is essential for developing novel, sustainable pest management strategies. This review highlights the multifaceted roles of salivary proteins in piercing-sucking insects. They are crucial for feeding (facilitating sheath formation and digestion), regulating growth and reproduction, and maintaining homeostasis. Notably, salivary proteins also modulate plant immunity, functioning as elicitors to trigger defenses or effectors to suppress them. Their functional diversity is further enhanced by evolutionary processes, including horizontal gene transfer, driving co-evolutionary dynamics between insects and plants. Salivary proteins show substantial agricultural potential as targets for RNA interference (RNAi)-based biopesticides and sources of resistance genes for engineering insect-resistant crops. Salivary proteins are critical regulators of plant-insect interactions and promising targets for next-generation pest control strategies. Future research should focus on elucidating less-explored functions, clarifying effector-receptor interactions, and employ multi-omics approaches to identify conserved targets. Translating these insights into applications, such as precision biopesticides and durable resistance in crops, will be crucial for establishing sustainable and effective crop protection systems. © 2026 Society of Chemical Industry.
Shang et al. (Sat,) studied this question.