Aim
The aim of this study was to evaluate the ability of Bacillus methylotrophicus M4‐1 to protect winter wheat from the harmful effects of soil salinity and alkalinity.
Methods and Results
We isolated the halotolerant B. methylotrophicus M4‐1. Two representative soils with different salt contents (S1, 213 μs cm−1; S2, 786 μs cm−1) in the Yellow River delta region of China were selected for experiments. The effects of the M4‐1 strain on the typical wheat variety (Jimai 21) in this environment were proven. In S1 soil, the M4‐1 strain reduced the wheat rhizosphere soil pH (1·61%) and electrical conductivity (EC) (8·01%) and increased the exchangeable K content (11·14%). The uptake of Mg2+ (20·73%) by wheat roots and K+ (8·84%) by leaves was increased, and the content of Na+ (23·62%) in leaves was reduced. In S2 soil, the M4‐1 strain was able to reduce soil EC (2·56%) and increase exchangeable K (11·20%) content. The absorption of K+ (13·28%) in wheat leaves was increased, and the content of Na+ (12·41%) in roots was decreased. Total N and organic matter contents in rhizosphere soil were significantly positively correlated with wheat growth and salt tolerance, whereas EC showed a significant negative correlation.
Conclusions
M4‐1 attenuates salt stress injury in wheat under both low and high salt stress.
Significance and Impact of the Study
We demonstrated the efficacy and value of plant growth‐promoting rhizobacteria addition to protect winter wheat against salt stress and improve crop yield. We also elucidated the physicochemical and biochemical interactions among M4‐1, the rhizosphere and the host plant.