Isolation, Screening, and Molecular Identification of Streptomyces sp. W-200 and Its Bioherbicidal Activity in Weed Control

Kwang Min Cho1   Seung Cheol Shin2   Aung  Bo Bo1   Mirjalol  Umurzokov2   WeiQiang  Jia3   Kee Woong  Park1,3,*   Jung Sup  Choi4,*   Young Sook  Kim4,*   

1Daeseung Biofarm Research Centre, Daejeon 24127, Korea
2Department of Crop Science, Chungnam National University, Daejeon 34134, Korea
3Beijing Fengdo High-Tech Seed Industry Co., Ltd., Beijing 1901, China
4Eco-friendly and New Materials Research Group, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea

Abstract

A total of 332 bacterial strains were isolated and screened for bioherbicidal activity. The three isolates namely W12, W-177, and W-200 were found to be efficient in suppressing Digitaria ciliaris by 88.3, 89.67, and 95.5% as compared with untreated control. Among them, the isolate W-200 caused severe injury to the growth of D. ciliaris, eventually leading to plant death. Phylogenetic analysis of 16S rRNA sequencing determined that the isolate W-200 was 99% similar to Streptomyces formicae (1H-GS9). Streptomyces strain W-200 was tested on D. ciliaris through soil and foliage applications. There was a progressive reduction in the growth of D. ciliaris in both applications. Optimization of bacterial culture conditions showed that Streptomyces strain W-200 was intense bioherbicidal activity and high cell mass at 25℃, 150 rpm, and initial pH 7. The herbicidal activity against D. ciliaris in light conditions was slightly higher than that in dark conditions. The chlorophyll content decreased by 96, 65, and 61% after treatment with paraquat, Streptomyces strain W-200, and glufosinate-ammonium, respectively at x1 recommended concentration. Electrolyte leakage increased gradually with time until 24 hours after treatment of Streptomyces strain W-200. These results suggested that Streptomyces strain W-200 producing herbicidal activity may be a new bioherbicide candidate.

Figures & Tables

Fig. 1. Herbicidal activities of 16 Streptomyces isolates on the growth of .