Soil Types Create Different Rhizosphere Ecosystems and Profoundly Affect the Growth Characteristics of Ratoon Sugarcane

Xiaoming Wang¹Jinghuan Zhu¹Shilong Wang^1*Junjun Ma²Zuli Yang³

• ¹Guangxi Science and Technology Normal University, Laibin, China
• ²Beijing Center for Physical and Chemical Analysis (BCPCA), Beijing, China
• ³Laibin Academy of Agricultural Sciences, Laibin, China

Rhizosphere ecological factors are important components of the ratoon sugarcane-soil feedback function. Little is known about the differences and relationships among rhizosphere ecological factors of ratoon sugarcane in different soil types (sandy soil, loam soil and clay soil) and their effects on growth and yield characteristics. This study was conducted using a combination of biochemical experiments and high-throughput sequencing. We investigated the differences and relationships among rhizosphere ecological factors of ratoon sugarcane in different soil types (sandy soil, loam soil and clay soil) and their effects on growth and yield characteristics. Biochemical function- and enzymatic activity-related factors in the rhizosphere soil were generally positively correlated with each other and sugarcane growth characteristics. For example, the correlation coefficients between soil respiration, soil catalase activity and theoretical sugarcane yield were 0.773 (p < 0.05) and 0.863 (p < 0.01), respectively. We found symbiotic relationships existed between the rhizosphere soil microbial and root system endophyte communities, and most functional differences in microbial communities between rhizosphere soils of different soil types were significant (P<0.05), indicating that the functional expression of rhizosphere soil microbial communities was more influenced by soil type. The abundance of bacteria and fungi in ratoon sugarcane rhizosphere soil was negatively and positively correlated with most soil biochemical functions, respectively, and correlations existed between the abundance of endophytic bacteria and fungi in the root system and sugarcane yield; this provides guidance for improving the structure of soil microbial communities. Eleven soil biochemical and functional factors were positively correlated with theoretical sugarcane yield and theoretical sugar yield indicators. Our findings suggest that different feedback directions and correlation strengths exist between sugarcane growth characteristics and various ecological factors in their rhizosphere in different soil types across spatial scales. This study can serve as a reference for improving soil in sugarcane fields.