Abstract:

Penicillium as one of the microorganisms causing apple mouldy core and core rot was subjected to high voltage electrostatic field (HVEF) treatment for different time to compare sporulation and germination of treated Penicillium spores during suspension culture at different temperatures. Meanwhile, the treated Penicillium spore suspension was inoculated into wounds in apples and infection rate and lesion diameter were measure every day during storage at 25 ℃. Results showed that no obvious difference in germination rate was observed between Penicillium spores with and without HVEF treatment during suspension culture at the same temperatures. However, the germination time of Penicillium spores was delayed due to HVEF treatment. In addition, sporulation had an obvious relationship with the treatment time of HVEF. Compared with Penicillium spore suspension treated with HVEF for 15 min or without FVEF treatment, Penicillium spore suspension with 30 min of HVEF treatment exhibited a lower sporulation after 7 days of culture at 20 ℃. Therefore, lower infection rate and smaller lesion diameter in apple inoculated with Penicillium spore suspension treated with HVEF were observed.

Key words: high voltage electrostatic field, Penicillium, sporulation, infection rate