Previously, we have reported a plant extract isolated from Lysimachia foenum gracum Herba as a new environment friendly biopesticide that has the mycelial growth inhibition effect on Magnaporthe oryzae, the pathogenic fungus of the rice blast disease. For the finding of additional biopesticide candidate, we tested the mycelial growth inhibitory effects about 700 species of plant extracts on PDA media. Among them, the extract of Anemarrhena asphodeloides showed prominent inhibitory effect of which IC50 was 139.7 ㎍/㎖. Mycelial radii of M. oryzae were measured on PDA medium containing the four organic solvent fractions isolated from total extract from A. asphodeloides. Ethyl acetate fraction showed the impressive inhibitory effect of IC50, 54.12 ㎍/㎖. In the subsequent rice field test for the total extract of A. asphodeloides, we obtained encouraging 62.0% control rate of rice blast disease without any phytotoxicity. It is almost equivalent to that of chemical pesticides implying the applicability of the extract as a new biopesticide. In further study, the analysis of active ingredients of the extract would be necessary for the development of a new biopesticide and for the verification of cellular mechanism by which the mycelial growth of M. oryzae inhibited.

Abstract
  Introduction
  Materials and Methods
  Results and Discussion
  References

• Myoung Ho Joo(Department of Plant Biotechnology, Chonnam National University, Department of Oriental Pharmaceutical Development, The Nambu University)
• Yu Mi Yeo(Department of Agricultural Biotechnology, National Institute of Agricultural Science, Rural Development Administration)
• Pil Son Choi(Department of Oriental Pharmaceutical Development, The Nambu University)
• Jae Hyeok Lee(Department of Oriental Pharmaceutical Development, The Nambu University)
• Kwang-Yeol Yang(Department of Plant Biotechnology, Chonnam National University)
• Young Jin Lee(Department of Oriental Pharmaceutical Development, The Nambu University) Corresponding author