Inhibitory Activity of Quaternary Ammonium Polymers against TMV Infection: Studies on Antiviral Substances for Plant Virus (Part 2)

Cationic quaternary ammonium polymers were tested for their antiviral activities against TMV infection on tobacco plants (Nicotiana tabacum L. cvs. Xanthi-nc and Bright Yellow). Chemicals were applied onto leaves of Xanthi-nc prior to TMV inoculation or with TMV inoculum. Among polymethacryloxyalkyl ammonium salts, poly (3-methacryloxy-2-methylpropyl-2-trimethylammonium methylsulfate) (MOBA·TMMS) showed the highest inhibitory activity. Copolymer of dimethyldiallylammonium chloride (MAA) and (3-chloro-2-hydroxy)-propyldiallylammonium hydrochloride (PAA) (MAA/PAA=6, CMPA) was the most effective among polydiallyl ammonium salts. CMPA showed the highest inhibitory activity on Bright Yellow tobacco to TMV infection through the infested soil. It was observed that the degree of flocculation of TMV by CMPA was significantly greater than that by sodium alginate, a known antiviral substance. Furthermore, CMPA was proved to be a stronger antiviral agent than sodium alginate in mixed inoculation method. Whereas, both polymers showed nearly equal antiviral activity in pre-treatment method.