To develop an environment-friendly fungicide for controlling tomato wilt diseases, antifungal active substance was isolated Rheum australe D. Don roots against Fusarium oxysporum f. sp. lycopersici, a pathogen of tomato wilt, in this study. Methanol extract obtained from Rheum australe roots was successively fractionated with hexane, chloroform, ethyl acetate, butanol and water. The ethyl acetate fraction, which showed the highest antifungal activity, was separated by column chromatography, and 60 subfractions were obtained. The 60 subfractions were anlayzed for antifungal activities by bioassay. The active compound was identified as 5-[(E)-2- (3-hydroxy-4-methoxyphenyl)ethenyl]benzene-1,3-diol (rhapontigenin) by NMR and GC-MS analysis. As a result of testing antifungal activity of rhapontigenin against Fusarium oxysporum, EC50 of rhapontigenin was showed strong antifungal activity at 7.48 mg/L. Therefore, this study showed that the Rheum australe roots extract can be a potential candidate which is a environment-friendly fungicide against Fusarium oxysporum.

Ⅰ. 서 론
Ⅱ. 재료 및 방법
    1. 실험재료
    2. 시약 및 기기
    3. 실험 병원균의 배양 조건
    4. MeOH 용매추출
    5. 용매분획 및 생물검정
    6. 항진균 활성물질 분리 및 정제
    7. 항진균 물질 구조 구명
    8. 균사생장 억제 실험
    9. 통계 분석 및 구조 분석
Ⅲ. 결과 및 고찰
References

• 최지수(경북대학교 대학원 생태환경시스템학과) | Choi Ji-Su
• 이동운(경북대학교 생태환경대학 생태과학과) | Lee Dong-Woon
• 최용화(경북대학교 생태환경대학 생태환경시스템학부) | Choi Yong-Hwa Corresponding author