Unravelling the Begomovirus-mediated Tomato Leaf Curl Disease: An In-depth Review of Pathogenesis and Host Interaction

Abstract

Tomato leaf curl disease (ToLCD), caused predominantly by begomoviruses (family Geminiviridae) and transmitted by the whitefly (Bemisia tabaci), represents one of the most devastating viral diseases of tomato worldwide. The disease exhibits symptoms such as upward leaf curling, mosaic patterns, stunted growth, and severe yield losses, posing a major threat to global tomato production. This  review provides an in-depth analysis of the molecular pathogenesis of begomovirus-mediated ToLCD, focusing on viral genome organisation, replication strategies, and the roles of viral proteins in host manipulation. We explore the complex host–virus interactions, including the modulation of host defence pathways, symptom development, and the interplay between the virus, vector, and host environment. The review also highlights advances in diagnostic tools, molecular characterization techniques, and insights from transcriptomic and proteomic studies that have enhanced understanding of ToLCD biology. Furthermore, it examines current strategies for disease management, including host resistance, RNA interference, and integrated vector management approaches. A deeper understanding of begomovirus–host interactions will be essential for mitigating the impact of ToLCD on global tomato production. By integrating recent findings from molecular biology, genetics, and plant–virus interaction studies, this review aims to unravel the molecular basis of ToLCD pathogenesis and highlight knowledge gaps that must be addressed to develop durable and sustainable disease management strategies.