We isolated Streptomyces scopuliridis KR-001 that produced herbicidal active metabolite(s) against several grass and broad leaf weeds. In this study, potential as natural herbicide of mutant N-29 broth filtrate of S. scopuliridis KR-001 was investigated to Ambrosia artemisiifilia in a greenhouse and field condition. The broth filtrate of mutant N-29 by foliar application showed a strong herbicidal activity to A. artemisiifilia with leaf stage in a greenhouse condition. Also, field trial of foliar application within treatment range had effectively controlled with early and middle stage of A. artemisiifilia at the natural habitats. Phytotoxic symptoms of mutant N-29 broth filtrate by foliar application were wilting and discoloration, and burn-down of leaves and finally plant death. These results suggest that mutant N-29 broth filtrate is considered possible as a natural herbicide for controlling environmentally friend to invasive alien plant such as A. artemisiifilia and may provide a new lead molecule for a more efficient herbicide.
Figures & Tables
Fig. 1. Herbicidal activity of foliar application of the mutant N-29 broth filtrate of S. scopuliridis KR-001 to A. artemisiifolia with early leaf stage (2-3Ls) in a greenhouse condition. Herbicidal activity was determined by visual injury (0: no injury, 100: complete death) at 5, 10 and 15 days after treatment. The abbreviation CK means untreated control in this pictures. The representative pictures were taken 15 days after foliar application. DAT, days after treatment.