Abstract: In this study, the effects of sugars, amino acids, phenolic acids, organic acids and the extract and powder of Atractylodes macrocephaia Koidz on the growth and replication of S.rolfsii and F. oxysporium were studied. The results showed that the growth of hypha was promoted by sucrose, glucose, maltose, rhamnose and mannose, but was inhibited by lactose, D (-)-fructose and xylose. The growth of hypha was also promoted by L-histidine, L-isoleucine, tyrosin, arginine, serine, proline and potassium nitrate, but was inhibited strongly by aspartic acid, cysteine. The growth of S. rolfsii was inhibited by caffeic acid, ethyl ester and vanillin but was promoted by catechin and affeic acid. The study also found that most allelochemicals had little influences on the growth of the two pathogens. Finally the growth of pathogen grown on the medium with different concentrations of extract and powder of A. macrocephaia was similar with those on 5% or 10% potato dextrose Agar. In conclusion, different carbon and nitrogen source and allelochemicals had different effects on the growth of the two pathogens．

Key words: Atractylodes macrocephaia Koidz, sugars, allelochemicals, Sclerotium rolfsii Sacc, Fusarium oxysporium