Molecular Insights into the Adaptability and Pathogenicity of Tomato Leaf Curl New Delhi Virus
Ajay S. Kadi *
University of Horticultural Sciences, Bagalkot- 587104, India.
Raghavendra Gunnaiah
Department of Biotechnology and Crop Improvement, University of Horticultural Sciences, Bagalkot- 587104, India.
C S Karthik
University of Horticultural Sciences, Bagalkot- 587104, India.
Venugopal K C
University of Horticultural Sciences, Bagalkot- 587104, India.
Manjunath ramanna
Department of Natural Resources Management, University of Horticultural Sciences, Bagalkot- 587104, India.
*Author to whom correspondence should be addressed.
Abstract
Tomato Leaf Curl New Delhi Virus (ToLCNDV), a highly destructive begomovirus, poses a significant threat to vegetable crops, particularly in the Indian subcontinent. First identified in tomato, ToLCNDV has expanded its host range to include cucurbits and other economically important crops. Transmitted by the whitefly vector Bemisia tabaci, the virus follows a persistent transmission mode, allowing its rapid spread across diverse agro-ecosystems. Despite efforts to control ToLCNDV, its adaptability and broad host range have made effective management challenging. This study explores the molecular mechanisms underlying ToLCNDV’s transmission and host adaptability, focusing on specific viral genetic features, such as the 36-nucleotide duplication in the DNA-B component, which may enhance its ability to manipulate host defenses. The research also highlights the virus’s interactions with satellite molecules like betasatellites, which suppress host gene silencing, further contributing to its virulence. Through comparative genome analysis using BLAST and phylogenetic methods, this study examines genetic diversity among ToLCNDV isolates. Findings demonstrate evolutionary adaptations that have facilitated the virus's spread and persistence across different crops and geographical regions. The study underscores the importance of developing integrated pest management strategies, breeding virus-resistant plant varieties, and identifying genetic markers associated with host resistance. By understanding ToLCNDV's genomic features and transmission dynamics, this research aims to inform strategies for mitigating its impact on global agricultural systems. Our research demonstrated that ToLCNDV infection disrupts key physiological processes in tomatoes, leading to stunted growth, leaf curling, and yield reduction. Furthermore, we observed that whiteflies retained the virus for up to two weeks, supporting its high transmission efficiency. These findings underscore the need for more targeted control strategies to mitigate the virus's impact on global agriculture.
Keywords: Tomato leaf, pathogenicity, plant diseases, agro-ecosystems, plant tissues