# Impact of Aspergillus flavus Infection on the Rhizosphere Bacterial Microbiota of Peanut (Arachis hypogaea L.)

## TL;DR

This study shows that infecting peanuts with Aspergillus flavus strains harms plant growth and changes the soil bacteria around the roots over time.

## Contribution

The study reveals time-dependent and strain-specific effects of A. flavus infection on peanut rhizosphere microbiota and plant growth.

## Key findings

- A. flavus infection significantly reduced peanut plant height and biomass.
- Early infection decreased bacterial diversity in the rhizosphere.
- Infection altered the abundance of key bacterial genera like KD4-96 and Sphingomonas.

## Abstract

This study investigated the effects of inoculating peanuts with two Aspergillus flavus strains (Aspergillus flavus CGMCC 3.4408 and A. flavus LNZW 23) on plant growth and the rhizosphere bacterial community. Infection significantly inhibited peanut growth. By 60 days post-inoculation (dpi), plant height in inoculated groups (CGMCC 3.4408, 26.4 cm; LNZW 23, 25.5 cm) was significantly lower than in the non-inoculated control (CK, 32.3 cm), with concomitant significant reductions in shoot and root biomass. Analysis of rhizosphere microbiota revealed that early infection (7 dpi) reduced bacterial species richness and phylogenetic diversity. Beta diversity analysis (PCoA) confirmed a significant divergence in microbial community structure between inoculated and control groups over time, with a statistically significant difference also observed between the two inoculated strains (p = 0.016). In terms of community composition, Proteobacteria, Acidobacteriota, and Actinobacteria were the three dominant phyla. At the genus level, infection altered the relative abundance of key taxa; genera such as KD4-96, Vicinamibacteraceae, and RB41 decreased at 7 dpi, while Sphingomonas remained relatively stable. By 60 dpi, community dominance increased, marked by rising abundances of Actinobacteria and Proteobacteria. In conclusion, A. flavus infection not only suppresses peanut growth but also persistently alters its rhizosphere microbial community, with effects demonstrating both time-dependency and strain-specificity.