An insight into plant–Tomato leaf curl New Delhi virus interaction

Abstract

Plants being sessile are constantly exposed to several stresses, which involve different types of abiotic and biotic stress factors. Biotic stress in plants is caused by various living organisms called plant pathogens including bacteria, viruses, fungi and parasites. Among these pathogens, plant viruses cause severe damage to world agricultural productivity. The reason behind such widespread destruction caused by viruses is their ability to frequently evolve them through mutation and genetic recombination, to succeed over the unfavourable conditions. The virus infects both susceptible and tolerant/resistant plants by the similar and systematic manner but resistant/tolerant plants combat the virus spread and suppress the viral growth. When pathogen enters the plant system, diverse defense responses are initiated which are mediated by plant disease resistance genes (R genes) mediated resistance and hormone based signaling pathways which restrict the viral spread by initiating hypersensitive response. To further enhance our knowledge regarding resistance mechanisms, the virus infection pattern and interactions of virus within resistant and susceptible plants needs to be analysed. At present, most successful strategy involves deployment of crops possessing resistance/tolerance against viruses with the foremost interest of detecting genes associated with resistance or recovery. Among several plant viruses, ‘Geminiviruses’ are the most devastating. In this article we have provided a comprehensive overview of Tomato leaf curl New Delhi virus (ToLCNDV), a member of family Geminiviridae and the plant defense system initiated against this virus. The evaluation of ToLCNDV infection in a variety of hosts differing in their tolerance and identification of differentially expressed genes would be helpful in speculating the threats associated with similar begomoviral invasions.