COS was applied by spraying it on tobacco leaves for inhibition of tobacco mosaic virus (TMV).
Some studies indicated that the defense response induced by COS was connected with NO pathway.
Effect of oligochitosan and SNP on local lesion production by TMV
SNP : Sodium nitroprusside,CPTIO:2,4-carboxyphenyl4,4,5,5 tetramethylimidazoline-1-oxyl-3-oxide
From: Induction of antiviral resistance and stimulary effect by oligochitosan in tobacco