Improvement of soil quality, microbial community structure and function with the application of microbial agent in continuous cropping of Pinellia ternata

Abstract

Background and aims

The continuous cropping obstacle (CCO) of Pinellia ternata has led to a sharp decline in both yield and quality, while the absence of effective mitigating measures seriously hinders the sustainable development of the industry. In this study, a microbial agent (MA) was applied to remit the CCO of P. ternata.

Methods

A microbial agent consisted of microbes with the function of allelochemical degradation, phosphate and potassium solubilization and nitrogen fixation was inoculated into the CCO soil of P. ternata. The growth condition and yield of tubers, physicochemical properties and microbial community of rhizosphere soil were determined.

Results

After inoculation, the growth and yield of P. ternata and the degradation of total phenolic acid were promoted, and the properties of soil were also improved, including pH value, organic matter content, concentration of nitrogen, phosphorus, and potassium, as well as the activity of urease, catalase, polyphenol oxidase and sucrase. In addition, the soil microbial community composition was optimized by the application of MA through increasing the abundance of beneficial microbes and inhibiting that of pathogens such as Fusarium. Moreover, the abundance of functional genes related to soil enzyme activity, allelochemicals degradation, nitrogen fixation, phosphorus and potassium solubilization, and plant growth promoting were also significantly increased after inoculation. Finally, the composition of MA was simplified according to the microbial colonization status, functional genes and the correlation analysis.

Conclusion

This study provided theoretical and technical guidance to alleviate the CCO of P. ternata and propose in-depth insights of the interactions among P. ternata, soil, and microbes.