Biological Control of Gray Mold Rot of Perilla Caused by Boftis cinerea 1. Resistance of Perilla Cultivars and Selection of Antagonistic Bacteria

Resistance of perilla varieties to Botrytis cinerea LVF12 was evaluated, while antagonistic bacteria were selected and tested for their efficacy towards biological control of gray mold rot caused by B. cinerea. Among 11 perilla varieties tested for disease resistance, Milyang variety showed some degree of resistance, while the rest of varieties showed no resistance. Among 250 bacterial isolates collected from perilla leaves and rhizosphere of perilla plants, six isolates showed high levels of inhibitory effect on mycelial growth and conidial germination of B. cinerea in in vitro test Using the pot test in growth chamber, these isolates showed high levels of disease suppression, with Nl isolate showing 95.3% of control value and N4 isolate showing 90.8% of control value. Further test was performed to evaluate the two isolates ability for disease prevention and/or disease therapy, and results showed almost 100% of control value. Isolates Nl and N4 were identified as Bacillus licheniformis and B. megaterium, respectively, according to Bergey`s manual, API 20E and 50CHB test kit, and Transmission electron microscope.