Potassium Silicate and Plant Growth‐promoting Rhizobacteria Synergistically Improve Growth Dynamics and Productivity of Wheat in Salt-affected Soils

Abstract

alinity is one of the most brutal environmental factors limiting the productivity of crop plants. Thus, there is an urgent need for environmentally friendly techniques to enhance growth and productivity of wheat ( Triticum aestivum L.) growing in saltine soils. In our 2-year field experiments, we evaluated the effect of two beneficial plant growth-promoting rhizobacteria (PGPR; Azospirillum brasilense and Bacillus circulans ) and the foliar application of potassium silicate (K 2 SiO 3 ; PS) to improve growth and yield of three cultivars of wheat, namely Misr 1, Gemmeza 12 and Sakha 95, under salt-affected soils (EC=7.71). The results supported our hypothesis that the combined application of PGPR+PS significantly ( P <0.05) improved growth and yield, nutrients (N, Na + and K + ) uptake, photosynthetic pigments, proline content, and total soluble sugars content compared to the individual application of PGPR or PS and the untreated (control) plants. In addition, the combined application significantly ( P <0.05) increased peroxidase and catalase activities, scavenging the damage effects of the reactive oxygen species. Our data revealed that the combined application could activate the soil key enzymes, mainly dehydrogenase and urease, and boost soil microbial activity. Overall, the combination of PGPR and PS applications, as a simple and low-cost biological method, has shown a positive effect in terms of improving soil properties, enhancing plant growth, and increasing element contents of wheat under salinity stress.