Use of Serendipita indica to improve soybean growth, physiological properties, and soil enzymatic activities under different Cd concentrations

Abstract

Abstract Background Plants-microbial technology has been regarded as a popular and applied new technique for the remediation of cadmium (Cd) polluted soils. Methods Therefore, a pot experiment was conducted to explore the effect of Serendipita indica (S. indica) on soybean growth and the soil enzyme activities, pH and Cd chemical fractions in the soil in 0, 3, 6, and 9 mg·kg−1 Cd concentrations. Results Results reflected that compared to uninoculated treatment, S. indica inoculation can still enhance the dry weight (66.57%) and shoot length (90.35%) and promote the net photosynthesis rate (72.18%), transpiration ratio (80.73%), and stomatal conductance (119.05%) of soybean under 9 mg·kg−1 Cd stress. Furthermore, the soil pH, phosphatase (116.39%), and catalase (4.17%) activities in the S. indica treatments were increased under 3 mg·kg−1 Cd concentration. Meanwhile, S. indica could shift Cd from exchangeable fraction to other stable fractions, primarily decreased Cd contamination degree/risk in 6 mg·kg−1 Cd concentration. Conclusions This work suggested that S. indica may be a potential biotechnology for low Cd-contaminated farmland, S. indica can not only alleviate Cd phytotoxicity and promote plant growth but also improve soil quality in Cd-contaminated soils. Graphical Abstract

Keywords

• Photosynthesis
• Soil enzyme activity
• Heavy metal, Bioremediation
• Serendipita indica (Piriformospora indica)
• Structural equation modeling (SEM), Transport factor
• Bioconcentration factor