Peptidomics-derived peptides enhance antiviral defense against ChiVMV in Nicotiana tabacum

Chilli veinal mottle virus (ChiVMV) is an important potyvirus for which deployable host resistance remains limited in breeding. Here, we used an omics-to-function workflow to identify infection-responsive peptides with antiviral activity. Peptidomics profiling of ChiVMV-inoculated Nicotiana tabacum at 1 and 3 days post inoculation revealed induced peptides, from which 21 candidates were prioritized based on induction strength and temporal reproducibility and then chemically synthesized. In a foliar-spray screen (-1 and + 1 dpi), three peptides showed reproducible but modest effects individually; when combined as a three-peptide cocktail, they significantly reduced ChiVMV accumulation in systemic leaves at 14 dpi and attenuated disease symptoms. Using a mild CMV-based VIGS system, silencing NtNPR1 or NtEIN2 compromised the antiviral efficacy of the cocktail, whereas silencing NtCOI1 did not. These results support peptidomics-guided discovery of peptide cocktails as a complementary strategy for ChiVMV control.