Screening of chilli varieties for resistance to chilli leaf curl virus and chilli leaf curl Sri Lanka virus by agroinoculation

Chilli (Capsicum spp.) is a widely cultivated crop in India that provides an essential source of income for many farmers. However, the productivity and quality of chilli crops are increasingly threatened by the devastating chilli leaf curl disease (ChiLCD), which is primarily caused by begomovirus infections transmitted by whiteflies. In this study, we aimed to evaluate the resistance or susceptibility of four different chilli varieties (Dhoom, Sita, Siera, and Bullet) to chilli leaf curl virus (ChiLCV) and chilli leaf curl Sri Lanka virus (ChiLCSLV). Partial dimer constructs of ChiLCV and ChiLCSLV were developed and these constructs after mobilising into Agrobacterium were used to agroinoculate on the four chilli varieties used in this study to determine their resistance or susceptibility. The results showed that all the tested chilli varieties were susceptible to both the viruses showing visible symptoms. The confirmation of this susceptibility was established through the presence of accumulated viral genomes within the host plants, as evidenced by PCR amplification. This study shows that all the four chilli varieties were susceptible to both the viruses with a difference in the time duration of symptom appearance, ChiLCV induced symptoms within 28 days whereas ChiLCSLV showed the symptoms at 40 days post inoculation. Our study provides a useful information for future breeding efforts to be focused on creating chilli varieties that are resistant to the virus.