Host-pathogen interactions are the fundamental basis of phytopathology, causing the suppression of plant immunity or interfering with normal cellular processes. Plants have developed multilayered defense systems to maintain resistance or induce susceptibility against these evolved pathogens. Tomato leaf curl New Delhi virus (ToLCNDV) offers a precise model for examining the molecular basics of plant-viral interactions in important crops. ToLCNDV is a bipartite begomovirus (family Geminiviridae) that poses a major threat to tomato production and has expanded its host range to various families of plants. Some hallmark disease symptoms are leaf curl upwards, puckering, vein clearing and distortion. The major cultivated host of ToLCNDV is tomato (Solanum lycopersicum L). However, the virus is known to infect several different plant species from various families, including Cucurbitaceae, Euphorbiaceae, Fabaceae, Malvaceae, and Solanaceae. ToLCNDV’s success is likely due to its wide host range and extremely adaptable genomic structure, which allows its DNA-A component to interface and trans-replicate with a variety of DNA-B components and beta satellites. Knowing that ToLCNDV may infect multiple plant species and propagate over a vast and ecologically diverse geographic range may help to clarify the possible economic risks connected to similar begomoviral invasions. ToLCNDV infection in tolerant cultivars triggers the up-regulation of defense-associated host genes, suggesting a complex relationship between the virus and host defense mechanisms. This chapter examines the host’s novel defense responses to ToLCNDV infection and how they affect tolerance or susceptibility. This chapter mainly discusses the molecular and genetic framework of ToLCNDV-tomato interaction, novel techniques and mechanisms for producing tolerant crops for quality food production, and suggests analytical insights to combat viral diseases in high-value crops.