Insect vectors in plant pathology: Transmission dynamics, manipulation and management

Vectors are responsible for the transmission of phytopathogens from one host to another, affecting both agronomic and horticultural crops. Among these, insect vectors such as aphids, whiteflies, leafhoppers, planthoppers, psyllids, and mealybugs are the primary carriers of a variety of plant pathogens across diverse cropping systems. These vectors are specialised in acquiring the pathogen from the diseased plant and transmitting the same to the uninfected plants, promoting recurrence of disease outbreaks. This review summarizes the role of insect vectors in plant pathology, highlighting vector diversity, pathogen transmission mechanisms, and different ecological, physiological and molecular processes governing vector competence. It further explores the mechanisms by which pathogens vector behaviour to promote their spread, while highlighting the effect of climatic factors on vector population and disease epidemiology. The review highlights that pathogen induced fitness effects in insect vectors are context dependent, revealing diverse evolutionary strategies underlying transmission success. The review further discusses the current and emerging vector management strategies, including biological, cultural, chemical and precision agriculture technologies. Overall, this review provides a foundation for understanding insect vector biology, modes of pathogen transmission by vectors, and the sustainable management of vector-borne plant diseases.