| Title | Bacterial Endophyte Sphingomonas sp. LK11 Produces Gibberellins and IAA and Promotes Tomato Plant Growth |
|---|---|
| Author | Abdul Latif Khan1, Muhammad Waqas2, Sang-Mo Kang2, Ahmed Al-Harrasi1*, Javid Hussain1, Ahmed Al-Rawahi1, Salima Al-Khiziri1, Ihsan Ullah2, Liaqat Ali1, Hee-Young Jung2, and In-Jung Lee2* |
| Address | 1Department of Biological Sciences and Chemistry, University of Nizwa, Nizwa Oman, 2School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Republic of Korea |
| Bibliography | Journal of Microbiology, 52(8),689–695, 2014, |
| DOI | 10.1007/s12275-014-4002-7 |
| Key Words | Solanum lycopersicum, Sphingomonas sp. LK11, endophytism, gibberellins, indole acetic acid |
| Abstract | Plant growth promoting endophytic bacteria have been identified as potential growth regulators of crops. Endophytic bacterium, Sphingomonas sp. LK11, was isolated from the leaves of Tephrosia apollinea. The pure culture of Sphingomonas sp. LK11 was subjected to advance chromatographic and spectroscopic techniques to extract and isolate gibberellins (GAs). Deuterated standards of [17, 17-2H2]-GA4, [17, 17-2H2]-GA9 and [17, 17-2H2]-GA20 were used to quantify the bacterial GAs. The analysis of the culture broth of Sphingomonas sp. LK11 revealed the existence of physiologically active gibberellins (GA4: 2.97 ± 0.11 ng/ml) and inactive GA9 (0.98 ± 0.15 ng/ml) and GA20 (2.41 ± 0.23). The endophyte also produced indole acetic acid (11.23 ± 0.93 μM/ml). Tomato plants inoculated with endophytic Sphingomonas sp. LK11 showed significantly increased growth attributes (shoot length, chlorophyll contents, shoot, and root dry weights) compared to the control. This indicated that such phyto-hormones-producing strains could help in increasing crop growth. |