Antiviral Activity of Three Plant Species, Rhus coriaria, Chenopodium quinoa, and Ailanthus altissima against Tobacco Mosaic Virus

Research on natural compounds provides new alternatives for effective and sustainable control of plant viral pathogens. Herein, we prepared and investigated the in vitro antiviral activity of 60 plant species from 22 families. The hydroethanolic extracts of Rhus coriaria, Chenopodium quinoa and Ailanthus altissima have strong inhibitions on Tobacco Mosaic Virus (TMV) infection. Hydroethanolic extract of C. quinoa with half-maximal Effective Concentration (EC50) value of 1.64 mg mL-1 exhibited the highest inhibitory effect against TMV. The extracts of R. coriaria and A. altissima with EC50 values of 2.82 and 4.42 mg mL-1, being compared with C. quinoa, showed an anti-TMV activity at higher concentrations, respectively. The systemic assay indicated that all of the three extracts reduced the symptoms and negative effects of TMV on tobacco plants. The chemical analysis of C. quinoa extract demonstrated a rich profile of saponins and anthocyanins, while A. altissima and R. coriaria extracts were rich in phenolic compounds. These results displayed that C. quinoa, R. coriaria, and A. altissima extracts had significant antiviral activity, and could be used as suitable sources for discovering new antiviral agents.