Microbial mechanism of zinc fertilizer input on rice grain yield and zinc content of polished rice

Yang Sean Xiao; Bo Zhou; Zhuangzhuang Han; Shenzhou Liu; Can Ding; Feifei Jia; Wenzhi Zeng

doi:10.3389/fpls.2022.962246

Microbial mechanism of zinc fertilizer input on rice grain yield and zinc content of polished rice

Front Plant Sci. 2022 Aug 25:13:962246. doi: 10.3389/fpls.2022.962246. eCollection 2022.

Authors

Yang Sean Xiao¹, Bo Zhou^{1

2}, Zhuangzhuang Han¹, Shenzhou Liu³, Can Ding⁴, Feifei Jia⁵, Wenzhi Zeng³

Affiliations

¹ College of Water Resources and Civil Engineering, China Agricultural University, Beijing, China.
² Engineering Research Center for Agricultural Water-Saving and Water Resources, Ministry of Education, Beijing, China.
³ State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China.
⁴ Guangxi Hydraulic Research Institute, Nanning, China.
⁵ College of Water & Architectural Engineering, Shihezi University, Shihezi, China.

Abstract

Zinc is an essential minor element for rice growth and human health, which can also change the structure of the microorganisms. However, it remains unclear for the effects of zinc fertilizer on microbiome function in agricultural soils and crops. To solve this research gap, we investigated the relationship between improving rice (Oryza sativa L.) yield, Zn concentration, soil microbial community diversity, and function by the application of Zn fertilizer. The field trials included three rice varieties (Huanghuazhan, Nanjing9108, and Nuodao-9925) and two soil Zn levels (0 and 30 kg ha^-1) in Jiangsu province, China. As a test, we studied the variety of soil bacterial composition, diversity, and function using 16S rRNA gene sequencing. The results showed that soil Zn application reduced the diversity of microbial community, but the bacterial network was more closely linked, and the metabolic function of bacterial community was improved, which increased the grain yield (17.34-19.52%) and enriched the Zn content of polished rice (1.40-20.05%). Specifically, redundancy analysis (RDA) and Mantel's test results revealed soil total nitrogen (TN) was the primary driver that led to a community shift in the rice rhizosphere bacterial community, and soil organic carbon (SOC) was considered to have a strong influence on dominant phyla. Furthermore, network analysis indicated the most critical bacterial taxa were identified as Actinobacteria, Bacteroidetes, Proteobacteria, and Chloroflexi based on their topological roles of microorganisms. KEGG metabolic pathway prediction demonstrated that soil Zn application significantly (p < 0.05) improved lipid metabolism, amino acid metabolism, carbohydrate metabolism, and xenobiotic biodegradation. Overall, their positive effects were different among rice varieties, of which Nanjing-9108 (NJ9108) performed better. This study opens new avenues to deeply understand the plant and soil-microbe interactions by the application of fertilizer and further navigates the development of Zn-rich rice cultivation strategies.

Keywords: bacterial community; co-occurrence network; microbial function; rice; zinc application.