Inhibitory Effect of Extracts from 33 Medicinal Herbs Against TMV and CMV Infection

Extracts of 33 medicinal herbs belonging to 28 different families used as precious resources in the Northeast Asia were tested for their antiviral activities against two major plant viruses. Twenty one methanol extracts from 19 different families were found to have a antiviral activity against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) when tested on indicator plants under greenhouse conditions. Most of these extracts have weak activities at the concentration used. But the methanol extracts of Phelinus linteus exhibited potent (98.7±1.3%) antiviral activity against TMV infection and also showed 97.2±2.2% activity against CMV infection. The methanol extracts of the gall of Rhus javanica also showed strong inhibitory efficacy over 98.7±1.1 % against TMV or CMV infection. Further research is needed to elucidate the active constituents of these medicinal herbs which may be useful in the development of new and effective antiviral agent against plant viruses.