Impacts of Fertilizers with Varying Nitrogen Contents on Millet Yield and Rhizosphere Soil 

Microbial Communities: Implications for Sustainable Agricultural Development

Ruifeng Guo; Yuemei Ren; Guangbing Ren; Shou Zhang; Jing Feng

High Latitude Crops Institute, Shanxi Agricultural University

Abstract: Nitrogen (N) is a vital macronutrient affecting crop productivity, yet the influence of different N contents in fertilizers on rhizosphere soil microbial diversity is not well understood. This study used high-throughput 16S rRNA and fungal ITS sequencing to examine the impact of varying N contents (low (LN, 90 kg/ha), medium (MN, 120 kg/ha), and high (HN, 150 kg/ha)) on root-associated microbial communities. The results revealed that Millet yield increased with N level: HN (7.14 Kg/ha) > MN (6.33 Kg/ha) > LN (5.62 Kg/ha), with HN yields significantly higher than LN (p< 0.05). No significant differences in microbial α-diversity were noted among three groups.Gemmatimonadota,Acidobacteri ota, andAscomycotawere the dominant phyla, whereasSphingomonas,Vicinamibacteraceae, and Fusarium were the predominant genera. LEfSe analysis showed thatEntotheonellaeota were substantially enriched in the LN group at the phylum level. At the genus level, there was marked enrichment ofRhodothermaceae:Fusicollawere in the LN group andPLTA13, Luteimonas, andEdaphobaculumwere in the MN group, whereasAridibacterandParviterri bactewere enriched in the HN group. Fertilizers with varying N contents affected rhizo sphere soil microbial community composition and millet yield. These findings provide valuable insights for developing scientifically-based fertilization strategies to promote sustainable agricultural ecosystems.

Keywords: millet; fertilizer application; microbial diversity; microbial community; sustainable agricultural development