Inhibitory effect of Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum

摘要

The influence of antagonistic Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum was studied in liquid cultures. Two strains of Pseudomonas spp. (B194 and B224), originally isolated from apple leaves and fruits, respectively, inhibited spore germination and germ tube elongation of B. cinerea or P. expansum. The inhibitory effect depended on the concentration of bacteria in the cultures. After a prolonged time of incubation (48–76 h) lysis and fragmentation of hyphae of both fungi was observed. In some cases the hyphae of B. cinerea developed abnormally if the bacterial strains were present – the hyphal tips were swollen and ball-shaped spore-like structures aggregated in chains were formed.