The biocompatible soil amendment boosts the winter wheat yield and modulates soil microorganisms under saline-alkaline stress

Nowadays, the globally increasing salinization of land is causing a growing shortage of food. To alleviate the saline and alkaline stress and enhance the crop yield, a biocompatible and low-cost soil amendment was developed. This was the combination of seaweed extract and poly-gamma-glutamic acid broth at a ratio of 50:50% (w:w). The amendment was evaluated in a soil column and winter wheat field experiments. The soil microorganisms were analysed by 16S rRNA high throughput sequencing. The results indicated that the soil amendment reduced the increment of salt content by 43.3% and 30.3% for topsoil and subsoil, respectively. The soil amendment enhanced the winter wheat yield by 10.7%. Meanwhile, the biocompatible soil amendment modified the composition, structure and diversity of soil bacteria, which contributed to the plant growth and crop yield. There was no significant effect on the fungi community. The soil amendment played a beneficial role in alleviating the salt stress and enhancing the winter wheat yield in a mildly saline and alkaline soil.