Jin Hee Jung, Sang woo Kim, Yun Seok Kim, Kabir Lamsal, Youn Su Lee*
Department of Applied Plant Sciences, Kangwon National University, Chuncheon 200-701, Korea
Correspondence to younslee@kangwon.ac.kr
Korean Journal of Mycology (Kor J Mycol) June 30, 2013, 41(2):118-126.
https://doi.org/10.4489/KJM.2013.41.2.118
Received: March 13, 2013; Revised: June 6, 2013; Accepted: June 20, 2013
Published: June 30, 2013.
©The Korean Society of Mycology
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
The experiment was carried out to analyze the inhibition effect of plant pathogenic fungi and growth promotion activity induced by the bacterial strains isolated from peatmoss. Among the isolated bacterial strains, B10-2, B10-4, B10-5 and B10-6 which showed more than 30% inhibition rate against Botrytis cinerea and Rhizoctonia solani in vitro, were further analyzed in the greenhouse for the growth promotion activity on lettuce (Lactuca sativa), pak-choi (Brassica compestris L. ssp. chinensis) and Chinese cabbage (Brassica campestris L. ssp. pekinensis). The results showed the treatment of B10-4 on lettuce showed the highest growth promotion activity with the leaf area (169.17cm²), fresh weight (leaf: 40.29 g, root: 8.80 g)and dry weight (leaf: 11.24 g, root: 4.17 g), which was about two folds as compared to control. On pak-choi, the growth promotion rate was the highest with the leaf area of 112.87cm², leaf fresh weight of 60.70 g, root fresh weight of 3.37 g, leaf dry weight of 14.34 g, and root dry weight of 1.90 g. As a result of treatment of B10-13 on chinese cabbage, the growth promotion rate was the highest with the leaf area (293.56cm²), fresh weight (leaf: 113.67 g, root: 2.40 g) and dry weight (leaf: 6.03 g, root: 0.53 g). The production of Indole Acetic Acid (IAA) and Indole-3-Butylic Acid (IBA) were also analyzed in these bacterial isolates. The IAA and IBA analyses were carried out in all bacterial isolates each day within the 5 days of incubation period. The highest production of IAA was observed with 112.57µg/mg protein in B10-4 after 3 days of incubation and IBA production was the highest in B10-2 with 58.71µg/mg protein after 2 days of incubation. Also, phosphate solubilizing activity was expressed significantly in B10-13 in comparison to that of other bacterial isolates. Bacterial identification showed that B10-2 was Bacillaceae bacterium and B10-5 was Bacillus cereus, B10-4 and B10-6 were Bacillus sp. and B-13 was Staphylococcus sp. by ITS sequence.
Bacillus sp., Growth promotion, Indole Acetic Acid (IAA), Indole-3-Butylic Acid (IBA)