Biological Control of Sclerotinia sclerotiorum in Lettuce Using Antagonistic Bacteria

Research in Plant Disease 2013;19(1):12-20.
Published online March 30, 2013.

보문 : 길항세균을 이용한 상추 균핵병의 생물학적 방제

전봉관 ( Bong Goan Chon ) , 박수지 ( Su Ji Park ) , 김진원 ( Jin Won Kim )

Biological Control of Sclerotinia sclerotiorum in Lettuce Using Antagonistic Bacteria

Bong-Goan Chon, Suji Park and Jin-Won Kim*

Department of Environmental Horticulture, The University of Seoul, Seoul 130-743, Korea

Received: January 17, 2013 Revised: February 06, 2013 Accepted: February 07, 2013

Abstract

To isolate antagonistic bacteria against sclerotinia rot of lettuce, caused by Sclerotinia sclerotiorum, soil samples were collected from the diseased greenhouse field in Namyangju city, Gyeong-gi province from 2007 to 2008. A total of 196 bacterial isolates were isolated using serial dilution method. In dual culture assay in vitro, 26 isolates showed more than 80% of inhibition rates of mycelial growth of S. sclerotiorum. Based on 16S rDNA sequence analysis, the 26 isolates were identified as Bacillus megaterium, B. cereus, B. subtilis, Arthrobacter nicotianae, A. ramosus, Pseudomonas filiscindens, Stenotrophomonas maltophilia, Brevibacterium frigoritolerans and Sphingobacterium faecium. The 26 isolates inhibited the mycelial growth of S. sclerotiorum up to 80% and the sclerotial germination 0?100%. In the greenhouse pot test of ten isolates conducted in summer, 2 isolates B. megaterium (DK6) and B. cereus (C210) showed control efficacy on sclerotia viability of S. sclerotiorum, 20% and 35%, respectively. In the greenhouse pot test in winter, the disease incidence of the control group was 80%, whereas those of 9 isolates among 26 were approximately 20%. From the result, the 9 isolates are expected as potentially antagonistic bacteria for biological control of sclerotinia rot of lettuce caused by S. sclerotiorum.

Key Words: Antagonistic bacteria, Biological control, Lettuce, Sclerotinia rot, Sclerotinia sclerotiorum