Abstract
Honeydew, a sugary excretion from sap-feeding insects, significantly influences plant-insect interactions. While extensive research has examined honeydew's composition, regulation, and role in insect-plant relationships, its direct effects on plant physiology and health remain understudied. This review synthesizes current knowledge about the effects of insect honeydew deposition on plant physiology and health, focusing on both beneficial and detrimental effects. Adverse impacts include sooty mold development, increased pathogen susceptibility, and reduced photosynthetic capacity due to surface occlusion. Beneficial effects encompass enhanced flowering, strengthened direct and indirect plant defense mechanisms, and improved soil fertility through indirect pathways. This review examines the relationship between honeydew composition and its effects on plants, while highlighting critical knowledge gaps in molecular mechanisms and long-term plant responses. This synthesis based on a comprehensive literature search provides a foundation for future research on honeydew's role in plant health and ecological interactions.