Title Gibberellins-Producing Rhizobacteria Increase Endogenous Gibberellins Content and Promote Growth of Red Peppers
Author Gil-Jae Joo1, Young-Mog Kim1, Jung-Tae Kim2, In-Koo Rhee3, Jin-Ho Kim4, and In-Jung Lee2,*
Address 1Institute of Agricultural Science and Technology, 2Division of Plant Bioscience, and, 3Division of Applied Biology and Chemistry, Kyungpook National University, Daegu 702-701, Republic of Korea, 4Department of Plant Resources, Sangju National University, Sangju 742-711, Republic of Korea
Bibliography Journal of Microbiology, 43(6),510-515, 2005,
DOI
Key Words growth-promoting interaction between rhizobacteria and plant, rhizobacteria producing gibberellins, root colonization
Abstract The growth of red pepper plants was enhanced by treatment with the rhizobacterium, Bacillus cereus MJ-1. Red pepper shoots showed a 1.38-fold increase in fresh weight (fw) and roots showed a 1.28-fold fw gain. This plant growth-promoting rhizobacterium (PGPR) has been reported to produce gibberellins (GAs). Other GAs-producing rhizobacteria, Bacillus macroides CJ-29 and Bacillus pumilus CJ-69, also enhanced the fw of the plants. They were less effective than B. cereus MJ-1, though. The endogenous GAs content of pepper shoots inoculated with MJ-1 was also higher than in shoots inoculated with CJ-29 or CJ-69. When inoculated with MJ-1, bacterial colonization rate of the roots was higher than that of roots inoculated with CJ-29 or CJ-69. These results support the idea that the plant growth-promoting effect of the bacteria also positively related with the efficiency of root colonization by the bacteria. In addition, we identified the major endogenous GAs of the red pepper as originating from both the early C-13 hydroxylation and the early non C-13 hydroxylation pathways, with the latter being the predominant pathway of GA biosynthesis in red pepper shoots.
Download PDF 510-515.pdf