Asian Journal
Of Traditional Medicines

Abstract: Root rot of Panax notoginseng is the most serious disease affecting its cultivation, which may be affected by its rhizosphere microbial community. We collected rhizosphere soil samples from Panax notoginseng suffering from root rot disease and isolated a strain designated SYP-B552. In the present study, strain SYP-B552 was found to be correlated with root rot disease and increased mortality of Panax notoginseng. Cells were Gram-negative, aerobic, non-motile and short rod shaped. The optimal growth of the strain occurred at 28°C and pH 7.0. The highest 16S rRNA gene sequences similarities between the strain SYP-B552 and other Chryseobacterium type strains were 98.10%. The predominant isoprenoid quinone was MK-6, and the major fatty acids were iso-C15:0 (40.07%) and Summed Feature 9 (comprising C16:0 10-methyl, 19.53%). The G+C content of the genomic DNA was 31.3 mol%. On the basis of the phylogenetic and biochemical data, strain SYP-B552 represents a species of the genus Chryseobacterium. Strain SYP-B552 could be regarded as pathogenic bacteria for exploring effective control measures for root rot disease in Panax notoginseng.

Key words: Panax notoginseng, root rot disease, pathogenic bacteria, biological characteristics, Chryseobacterium sp