Abstract: The antifungal activity of the extract of Coptis chinensis against Gibberella zeae, Helminthosporium maydis, Rhizoctonia solani, Botrytis Cinerea and Sclerotinia sclerotiorum was determined by the plate growth rate method.The synergistic effects of extracts were tested using double dilution plate method.The results showed that the inhibition rates of C.chinensis extract against G.zeae, H.maydis, R.solani, B.Cinerea and S.sclerotiorum were 93.39%,96.89%,70.92%,100% and 91.22% respectively.Meanwhile,its action mechanism was studied by means of spore germination inhibition,mycelial morphology and cell membrane permeability.

Key words: Coptis chinensis, antifungal activity, mechanism