Effects of continuous cropping on bacterial community diversity and soil metabolites in soybean roots

Liwei An ¹ Xinnan Lu ¹ Pengyu Zhang ² Jiayao Sun ³ Baiming Cong ³ rula sa ¹ Dexin HE ^1*

• ¹ Inner Mongolia University for Nationalities, Tongliao, China
• ² Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Hohhot, Inner Mongolia Autonomous Region, China
• ³ Tongliao Institute of Agricultural and Animal Husbandry Sciences, tongliao, China

The rotating crop of corn and soybeans is regarded as an effective strategy for addressing current issues in soybean farming. Yet, the precise mechanisms controlling the bacterial microbiome in soybean roots in the soil, utilized in continuous cropping and rotational corn-soybean farming, are still unclear. This study utilized both field and pot positioning experiments, using high-throughput and generic metabolomics sequencing techniques to investigate the dynamics between soybean plants-root microflora-soil metabolite, especially in the setting of continuous cropping and fluctuating corn-soybean crop. The process that included rotating corn soybeans significantly enhanced their grain yield, dry weight, soil nitrogen concentration, urease activity, and the accumulation of nitrogen, phosphorus, and potassium in various organs, compared to the steady-growing soybean approach. A notable decrease is observed in the transit of bacterial OTUs from the rhizosphere to the endosphere through rhizoplane; the quantity of bacterial OTUs consumed and enriched on rhizoplane exceeds the number that is enriched and absorbed in endosphere. Continuous cropping practices significantly improve Burkholderiales, while Chloroplast flora significantly enhance crop rotation methods. Soil environmental factors such as urease and accessible phosphorus are crucial in establishing the relative prevalence of Rhodanobacter and other bacterial groups. Soil metabolites, like Benzyl Alcohol, are positively correlated with Cyanobacteria, while acidic substances, including D-Arabinitol, are positively associated with Burkholderiales. The study shows that the cycle of corn and soybean crops enhances soybean growth, increases nutrient accumulation in plants and soil, elevates the presence of beneficial bacteria, and improves soybean yields.