Send to

Choose Destination
Physiol Plant. 2016 Sep;158(1):34-44. doi: 10.1111/ppl.12441. Epub 2016 Apr 25.

Induced maize salt tolerance by rhizosphere inoculation of Bacillus amyloliquefaciens SQR9.

Author information

Jiangsu Key Lab and Engineering Center for Solid Organic Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, Nanjing 210095, P.R. China.
Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, P.R. China.


Salt stress reduces plant growth and is now becoming one of the most important factors restricting agricultural productivity. Inoculation of plant growth-promoting rhizobacteria (PGPR) has been shown to confer plant tolerance against abiotic stress, but the detailed mechanisms of how this occurs remain unclear. In this study, hydroponic experiments indicated that the PGPR strain Bacillus amyloliquefaciens SQR9 could help maize plants tolerate salt stress. After exposure to salt stress for 20 days, SQR9 significantly promoted the growth of maize seedlings and enhanced the chlorophyll content compared with the control. Additional analysis showed that the involved mechanisms could be the enhanced total soluble sugar content for decreasing cell destruction, improved peroxidase/catalase activity and glutathione content for scavenging reactive oxygen species, and reduced Na(+) levels in the plant to decrease Na(+) toxicity. These physiological appearances were further confirmed by the upregulation of RBCS, RBCL, H(+) -PPase, HKT1, NHX1, NHX2 and NHX3, as well as downregulation of NCED expression, as determined by quantitative reverse transcription-polymerase chain reaction. However, SQR9 counteracted the increase of abscisic acid in response to salt stress. In summary, these results show that SQR9 confers plant salt tolerance by protecting the plant cells and managing Na(+) homeostasis. Hence, it can be used in salt stress prone areas, thereby promoting agricultural production.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center