Abstract:

In this paper some dominant rhizosphere fungi of the Ostryopsis davidiana were collected and its metabolites were extracted from the liquid pure culture. The metabolites in different concentrations were added to the culture medium for 60-day-old seedlings of Piuns tabulaeformis to investigate allelopathic effects that rhizosphere fungi of Ostryopsis davidiana might have on Piuns tabulaeformis. The results showed that the strain P3 of Paecilomyces and strain S1 of Stachybotrys significantly promoted seedling growth, and the effect was strengthened as the concentration increased. However, strain P1 of Paecilomyces obviously inhibited seedling growth. Strain G1 of Gliocladium and strain P2 of Paecilomyces showed effects of promoting seedling growth in low concentrations, and prohibiting seedling growth in high concentrations. On the base of allelopathic effects study, we chose three strains which had obvious effects on the Piuns tabulaeformis, i.e. P3, S1, P1, and then cultivated them in liquid pure culture method. The chemical productions were analyzed by GC/MS method, and compounds, such as oleic acid, methyl ester; 9-octadecenoic acid(E); 9,12-octadecadienoic acid(Z,Z); 9-octadecenoamide; hexahydropyrrolo(1,2-α) pyrazine-1,4-dione were detected in the promoting strains(P3, S1), and lycoxanthin and euphorbiae diterpene glycol were found in inhibiting strain (P1).

Key words: Piuns tabulaeformis, Ostryopsis davidiana, allelopathic effect, fungi