Bacillus Thuringiensis Enhances the Ability of Ryegrass to Remediate Cadmium-Contaminated Soil

Abstract

Phytoremediation technology has been widely used for the remediation of heavy metals in soil due to its favorable environmental and ecological effects, but establishing a single phytoremediation technology can result in bottlenecks, such as a long cycle, low biomass, and difficulty in root absorption. At present, inoculation with microorganisms that could assist plants in their remediation of contaminated soils is attracting increasing attention. Therefore, in this study we selected ryegrass and Bacillus thuringiensis (SY) and analyzed the effects of SY inoculation on the growth of ryegrass, including the accumulation of Cd in ryegrass, changes in heavy metal forms, and the heavy metal content in rhizosphere soil, using pot experiments. The results indicate that SY inoculation promotes root growth and development of the ryegrass and the accumulation of cadmium in the plants. In addition, SY inoculation increased the levels of soil nutrients and the activities of soil urease, sucrase, and alkaline phosphatase. This study reveals that the use of SY improves the remediation efficiency of ryegrass for cadmium-contaminated soil, and supports the application potential of microorganisms in soil remediation technology.