Abstract:

The antifungal action and potential mechanism of pyrolin against Physalospora piricola were studied. The results showed that Physalospora rot of apples could be significantly suppressed by Pyrolin, and the MIC value was 0.156 mg·mL^-1 and MFC value was 0.313 mg·mL^-1. The activities of PPO and PAL in apples increased significantly on inoculation with Pyrolin and a pathogen,P. piricola or the pathogen alone, and maintained at a high level throughout the experiment. Moreover, fruits inoculated with Pyrolin + P. piricolaor P. piricolaalone also stimulated POD activity. The observations with SEM revealed that hyphae distorted, the mycelium adhered, substance of flocculent agglutination occurred on cell surface. The observations with TEM showed that the hypha cell inner structure was disordered and damaged severely.

Key words: pyrolin, Physalospora piricola, polyphenol oxidase, peroxidase, phenylalanine ammonium-lyase, ultrastructure