Effect of Funneliformis mosseae and Thiobacillus thioparus on sulfur utilization in soybean sterilized soil under continuous cropping

PurposeThis study was to investigate the regulation of sulfur status in continuous-cropping soybean soil by Funneliformis mosseae and Thiobacillus thioparus and promote the absorption of sulfur in soybean. To explore the interactions among F. mosseae, T. thioparus and soybean plants, this study laid a theoretical foundation for the application of F. mosseae and T. thioparus as biological agents in agricultural production.MethodsPot culture, a two-compartment system and shake-flask culture were used in the experiment. Using F. mosseae and T. thioparus as experimental inoculants, the effects of F. mosseae on sulfur oxide of T. thioparus and their interaction on the growth of soybean plants were studied from the aspects of soil sulfur content, sulfur functional genes and the growth of soybean and sulfur-oxidizing bacteria.ResultsThe F. mosseae and T. thioparus inoculation significantly increased the abundance of sulfur-oxidizing bacteria and available sulfur content in the soil, stimulated the expression of sulfate transporter genes in soybean roots, and promoted the absorption of sulfur nutrients in soybean. F. mosseae stimulated the expression of the T. thioparus sulfur-oxidation gene and enhanced the sulfur-oxidation capacity, while T. thioparus enhanced F. mosseae colonization of soybean roots. Thus, F. mosseae and T. thioparus promoted soil sulfur cycling and sulfate transport in soybean roots, which proved that F. mosseae could effectively improve the sulfur-oxidation capacity of T. thioparus.ConclusionDouble inoculation with F. mosseae and T. thioparus significantly promoted soybean plant growth and increased soil sulfur utilization.