Silicon Application Modulates the Growth, Rhizosphere Soil Characteristics, and Bacterial Community Structure in Sugarcane

Quanqing Deng; Taobing Yu; Zhen Zeng; Umair Ashraf; Qihan Shi; Suihua Huang; Tengxiang Lian; Jianwen Chen; Wardah Muzaffar; Wankuan Shen

doi:10.3389/fpls.2021.710139

Silicon Application Modulates the Growth, Rhizosphere Soil Characteristics, and Bacterial Community Structure in Sugarcane

Front Plant Sci. 2021 Aug 20:12:710139. doi: 10.3389/fpls.2021.710139. eCollection 2021.

Authors

Quanqing Deng^{1

2}, Taobing Yu³, Zhen Zeng^{1

2}, Umair Ashraf⁴, Qihan Shi³, Suihua Huang^{1

3

5}, Tengxiang Lian³, Jianwen Chen^{1

2}, Wardah Muzaffar⁶, Wankuan Shen^{1

2

5}

Affiliations

¹ College of Agriculture, South China Agricultural University, Guangzhou, China.
² Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China.
³ The State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, Guangdong, China.
⁴ Division of Science and Technology, Department of Botany, University of Education, Lahore, Pakistan.
⁵ Scientific Observing and Experimental Station of Crop Cultivation in South China, Ministry of Agriculture, Guangzhou, China.
⁶ Sugarcane Research Institute, Ayub Agricultural Research Institute, Faisalabad, Pakistan.

Abstract

Silicon (Si) deficiency, caused by acidic soil and rainy climate, is a major constraint for sugarcane production in southern China. Si application generally improves sugarcane growth; however, there are few studies on the relationships between enhanced plant growth, changes in rhizosphere soil, and bacterial communities. A field experiment was conducted to measure sugarcane agronomic traits, plant nutrient contents, rhizosphere soil enzyme activities and chemical properties, and the rhizosphere bacterial community diversity and structure of three predominant sugarcane varieties under two Si treatments, i.e., 0 and 200 kg of silicon dioxide (SiO₂) ha^-1 regarded as Si0 and Si200, respectively. Results showed that Si application substantially improved the sugarcane stalk fresh weight and Si, phosphorus (P), and potassium (K) contents comparing to Si0, and had an obvious impact on rhizosphere soil pH, available Si (ASi), available P (AP), available K (AK), total phosphorus (TP), and the activity of acid phosphatase. Furthermore, the relative abundances of Proteobacteria showed a remarkable increase in Si200, which may be the dominant group in sugarcane growth under Si application. Interestingly, the AP was noticed as a major factor that caused bacterial community structure differences between the two Si treatments according to canonical correspondence analysis (CCA). In addition, the association network analysis indicated that Si application enriched the rhizosphere bacterial network, which could be beneficial to sugarcane growth. Overall, appropriate Si application, i.e., 200 kg SiO₂ ha^-1 promoted sugarcane growth, changed rhizosphere soil enzyme activities and chemical properties, and bacterial community structures.

Keywords: association network analysis; bacterial community structure; illumina miseq sequencing; silicon; soil enzymes activities; soil properties; sugarcane.