Metabolism-mediated induction of zinc tolerance in Brassica rapa by Burkholderia cepacia CS2-1

• Published in: The journal of microbiology Vol. 55; no. 12; pp. 955 - 965
• Main Authors: Kang, Sang-Mo, Shahzad, Raheem, Bilal, Saqib, Khan, Abdul Latif, You, Young-Hyun, Lee, Won-Hee, Ryu, Hee-La, Lee, Ko-Eun, Lee, In-Jung
• Format: Journal Article
• Language: English
• Published: Seoul The Microbiological Society of Korea 01.12.2017; Springer Nature B.V; 한국미생물학회
• Subjects: Abscisic acid; Acetic acid; Amino acids; Antioxidants; Bioaccumulation; Biomedical and Life Sciences; Bioremediation; Brassica; Brassica oleracea; Brassica rapa; Burkholderia cepacia; Chinese cabbage; Flavonoids; Heavy metals; Hormones; indole acetic acid; Indoleacetic acid; Inoculation; Irrigation water; Life Sciences; Metabolism; Metal concentrations; metal tolerance; Microbial Ecology and Environmental Microbiology; Microbiology; Minerals; nucleotide sequences; Oxidative stress; Phenols; Phylogeny; Plant growth; Plants (botany); Pollution tolerance; ribosomal RNA; rRNA 16S; Salicylic acid; siderophores; Superoxide dismutase; Synthesis; Toxicity; Traditional foods; Uptake; Water pollution; Zinc; 생물학; abscisic acid; antioxidant; salicylic acid; zinc toxicity; amino acid; plant growth-promoting rhizobacterium
• ISSN: 1225-8873; 1976-3794; 1976-3794
• DOI: 10.1007/s12275-017-7305-7

Brassica rapa (Chinese cabbage) is an essential component of traditional Korean food. However, the crop is often subject to zinc (Zn + ) toxicity from contaminated irrigation water, which, as a result, compromises plant growth and production, as well as the health of human consumers. The present study investigated the bioaccumulation of Zn + by Burkholderia cepacia CS2-1 and its effect on the heavy metal tolerance of Chinese cabbage. Strain CS2-1 was identified and characterized on the basis of 16S rRNA sequences and phylogenetic analysis. The strain actively produced indole-3-acetic acid (3.08 ± 0.21 μg/ml) and was also able to produce siderophore, solubilize minerals, and tolerate various concentrations of Zn + . The heavy metal tolerance of B. rapa plants was enhanced by CS2-1 inoculation, as indicated by growth attributes, Zn + uptake, amino acid synthesis, antioxidant levels, and endogenous hormone (ABA and SA) synthesis. Without inoculation, the application of Zn + negatively affected the growth and physiology of B. rapa plants. However, CS2-1 inoculation improved plant growth, lowered Zn + uptake, altered both amino acid regulation and levels of flavonoids and phenolics, and significantly decreased levels of superoxide dismutase, endogenous abscisic acid, and salicylic acid. These findings indicate that B. cepacia CS2-1 is suitable for bioremediation against Zn + -induced oxidative stress.