Identification of interior salt-tolerant bacteria from ice plant Mesembryanthemum crystallinum and evaluation of their promoting effects
- 7 Downloads
Endophytic bacteria can stimulate host plant development. Insufficient information is available about NaCl-tolerant bacteria that colonize ice plants (Mesembryanthemum crystallinum) in their habitats. In this study, a culture-dependent method was used to isolate endophytic nitrogen-fixing bacteria from ice plants, and the resulting cultures were screened for salt-stress tolerance in vitro. A total of 17 salt-tolerant bacteria were obtained. The majority of the isolates grew well in 2.05 M NaCl with a maximum tolerance at 3.59 M. Most of the strains were Gram-positive bacteria with various plant growth-promoting traits. The 16S rRNA gene sequences revealed that the 17 isolates were distributed within three genera and corresponded to the bacterial species Halomonas sp., Bacillus sp., and Planococcus sp. Inoculation of cabbage (Brassica olereacea) seeds with selected strains showed that the strain MC1 promoted seed germination, and the same strain significantly increased root dry weight under saline stress by 24.5%. Our study suggests that ice plants naturally accommodate a variety of salt-tolerant endophytic bacteria and that these bacteria are able to relieve abiotic stress during plant growth.
KeywordsSalt-tolerance Nitrogen-fixing bacteria Ice plant Vegetable crop Saline condition
This work was financially supported by the National Natural Science Foundation of China (Grant No.31701968), the Anhui Science and Technology Project (1704a07020078), the Dean’s Youth Innovation Project (17B0307), and the Vegetable Cultivation Scientific Innovation Team (18C0309) from Anhui Academy of Agricultural Sciences. We gratefully acknowledge two anonymous referees and editors who provided valuable and constructive suggestions to improve this manuscript.
ZJ and WPC planed and designed the research. ZJ, WPC, WY, JHK, and YCS performed the experiments. ZJ, WPC, and THM analyzed the data. ZJ, WPC, WY, and THM wrote the manuscript.
Compliance with ethical standards
Conflict of interest
The authors have declared that no competing interests exist.
- Agarie S, Shimoda T, Shimizu Y, Baumann K, Sunagawa H, Kondo A, Ueno O, Nakahara T, Nose A, Cushman JC (2007) Salt tolerance, salt accumulation, and ionic homeostasis in an epidermal bladder-cell-less mutant of the common ice plant Mesembryanthemum crystallinum. J Exp Bot 58:1957–1967CrossRefPubMedGoogle Scholar
- Barkla BJ, Castellanos-Cervantes T, de León JL, Matros A, Mock HP, Perez-Alfocea F, Salekdeh GH, Witzel K, Zörb C (2013) Elucidation of salt stress defense and tolerance mechanisms of crop plants using proteomics-Current achievements and perspectives. Proteomics 13:1885–1900CrossRefPubMedGoogle Scholar
- Chakdar H, Pabbi S (2017) A comparative study reveals the higher resolution of RAPD over ARDRA for analyzing diversity of Nostoc strains. 3. Biotech 7:125Google Scholar
- Chiang CP, Yim WC, Sun YH, Ohnishi M, Mimura T, Cushman JC, Yen HE (2016) Identification of ice plant (Mesembryanthemum crystallinum L.) microRNAs using RNA-Seq and their putative roles in high salinity responses in seedlings. Front. Plant Sci 7:1143Google Scholar
- Hoagland DR, Arnon DI (1950) The water-culture method for growing plants without soil. Circ Calif Agric Exp Stn 347:4–31Google Scholar
- Kumar RS, Ayyadurai N, Pandiaraja P, Reddy AV, Venkateswarlu Y, Prakash O (2005) Characterization of antifungal metabolite produced by a new strain Pseudomonas aeruginosa PUPa3 that exhibits broad-spectrum antifungal activity and biofertilizing traits. J Appl Microbiol 98:145–154CrossRefPubMedGoogle Scholar
- Moore FP, Barac T, Borremans B, Oeyen L, Vangronsveld J, van der Lelie D, Campbell CD, Moore ER (2006) Endophytic bacterial diversity in poplar trees growing on a BTEX-contaminated site: The characterisation of isolates with potential to enhance phytoremediation. Syst Appl Microbiol 29:539–556CrossRefPubMedGoogle Scholar
- Qin S, Zhang YJ, Yuan B, Xu PY, Xing K, Wang J, Jiang JH (2014) Isolation of ACC deaminase-producing habitat-adapted symbiotic bacteria associated with halophyte Limonium sinense (Girard) Kuntze and evaluating their plant growth-promoting activity under salt stress. Plant Soil 374:753–766CrossRefGoogle Scholar
- Sadfi-Zouaoui N, Essghaier B, Hajlaoui MR, Fardeau ML, Cayaol JL, Ollivier B, Boudabous A (2008) Ability of moderately Halophilic bacteria to control grey mould disease on tomato fruits. J Phytopathol 156:42–52Google Scholar
- Sazzad H, Dietz KJ (2016) Tuning of redox regulatory mechanisms, reactive oxygen species and redox homeostasis under salinity stress. Front Plant Sci 7:548Google Scholar
- Zinniel DK, Lambrecht P, Harris NB, Feng Z, Kuczmarski D, Higley P, Ishimaru CA, Arunakumari A, Barletta RG, Vidaver AK (2002) Isolation and characterization of endophytic colonizing bacteria from agronomic crops and prairie plants. Appl Environ Microbiol 68:2198–2208CrossRefPubMedPubMedCentralGoogle Scholar