The Microbial Community Structure of Rhizosphere Soil was Influenced by Different Sugarcane Varieties with Different Ratooning Abilities

Strong ratoon ability is the key factor in improving sugarcane productivity and reducing production costs. Soil microorganisms are sensitive to environmental changes and play an important role in regulating soil ecological functions. However, the impacts of sugarcane varieties with different ratooning abilities on soil microorganisms are poorly understood. Therefore, two common cultivated varieties with different ratooning abilities (Yuetang 94-128 with strong ratooning ability and Yuetang 03-373 with low ratooning ability) were selected to study the effects of sugarcane varieties on sugarcane yield and microbial community structure from 2017 to 2019 in South China. The Illumina MiSeq platform was applied in the present study to detect the diversity and community structure of rhizosphere soil bacteria and fungi in the different sugarcane varieties in 2019. The results showed that sugarcane cane yield and sugar yield were higher in Yuetang 94-128 during the three years, whereas the sugar content was lower in Yuetang 94-128 than in Yuetang 03-373 during this time. Different years influenced cane yield and sugar yield, while the sucrose content remained stable during the different years. The pH, organic matter (SOM) and total nitrogen (TN) contents were significantly lower in Yuetang 03-373 than in Yuetang 94-128, whereas the other indices had no significant difference between the different varieties. The α-diversity of sugarcane rhizosphere soil bacteria and fungi was not significantly different between the different varieties. Compared with Yuetang 03-373, the increase in bacterial taxa associated with the soil carbon and nitrogen cycles may be one of the reasons for the strong ratooning of Yuetang 94-128. The difference in rare fungal taxa between the two sugarcane varieties may lead to different ecological functions in the soil. Redundancy analysis (RDA) and Mantel test showed that the soil physical and chemical properties did not significantly influence the microbial community structure, which could indicate that sugarcane variety was the primary variable responsible for microbial community structure. This study provided important information on the rhizosphere soil microbial community structure of different sugarcane varieties with different ratooning abilities and provided a theoretical basis for improving the ratooning ability of sugarcane varieties from the perspective of improving soil microbial community.