Abstract: A fungus Aspergillus niger strain isolated from the inner bark of Taxus chinensis and its hydrolyzed product polysaccharides were used to treat Taxus chinensis leaves. Both treatments decreased the dry weight and chlorophyll content of the leaves meanwhile increased malondialdehyde (MDA) content compared with the control, and fungi led to more distinguishable outcome than polysaccharides did, indicating that both fungus and fungal polysaccharides destroyed leaves while the latter had less damaging effects. Furthermore, Polysaccharides could notably increase content of protein and phenolics, evoke activity of peroxidase and phenylalanine ammonia-lyase, whereas the fungus had the contrary effects. Thus, it demonstrated that polysaccharides have inducing effects on defense reaction of Taxus chinensis while the fungus strain itself does not.

Key words: Taxus chinensis, Aspergillus niger, disease response