Address |
1Department of Food Science, Gyeongnam National University of Science and Technology, Jinju 660-758, Republic of Korea, 2Department of Biochemistry & Molecular Biology, Hajee Mohammad Danesh Science & Technology University, Dinajpur 5200, Bangladesh, 3Research Institute of Life Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea |
Abstract |
The study aimed to reveal the diversity of endophytic bacteria
in the roots of Chinese cabbage (CC) cultivated in two areas
in Korea, namely, Seosang-gun (SS) and Haenam-gun (HN),
and also in a transgenic plant (TP) from the laboratory. A
total of 653 colonies were isolated from the interior of CC
roots, comprising 118, 302, and 233 isolates from SS, HN,
and TP samples, respectively. Based on 16S rRNA gene sequence
analysis, the isolates belonged to four major phylogenetic
groups: high-G+C Gram-positive bacteria (HGC-GPB),
low-G+C Gram-positive bacteria (LGC-GPB), Proteobacteria,
and Bacteriodetes. The most dominant groups in the roots of
the SS, HN, and TP cultivars were LGC-GPB (48.3%), Proteobacteria
(50.2%), and HGC-GPB (38.2%), respectively.
Importantly, most of the isolates that produced cell-walldegrading
enzymes belonged to the genus Bacillus. Bacillus sp.
(HNR03, TPR06), Bacillus pumilus (SSR07, HNR11, TPR07),
and Bacillus subtilis (TPR03) showed high antagonism against
the tested food-borne pathogenic bacteria. In addition, Bacillus
sp. (HNR03, TPR06), Bacillus pumilus (SSR07, HNR11,
HNR17, TPR11), Microbacterium oxidans (SSR09, TPR04),
Bacillus cereus HNR10, Pseudomonas sp. HNR13, and Bacillus
subtilis (TPR02, TPR03) showed strong antagonistic activity
against the fungi Phythium ultimum, Phytophthora capsici,
Fusarium oxysporum, and Rhizoctonia solani. The endophytes
isolated from the TP cultivar showed the strongest antagonistic
reactions against pathogens. This study is the first report
on endophytic bacteria from Chinese cabbage roots. |