# Niches and Genotypes Determine the Diversity and Composition of Microbiomes After Herbicide Treatment in Beckmannia syzigachne

## TL;DR

This study explores how herbicides affect the microbial communities in the weed Beckmannia syzigachne, revealing differences in bacterial and fungal diversity based on plant genotype and root niche.

## Contribution

The study identifies how herbicide treatment influences microbial community composition in different root niches and genotypes of Beckmannia syzigachne.

## Key findings

- Bacterial diversity decreases from bulk soil to the endosphere in Beckmannia syzigachne.
- The sensitive genotype has higher bacterial diversity than the resistant biotype.
- Resistant populations contain unique fungal species like Saccharomyces sp. and Apiotrichum montevideense.

## Abstract

Plant-associated microbes play a crucial role in plant adaptability by facilitating nutrient acquisition, growth, and stress resistance. However, the effects of herbicides on microbial communities in different root-associated niches and their impact on weed–microbe interactions are not well understood. Beckmannia syzigachne, a problematic weed, reduces crop yield and quality. In this study, we investigated bacterial and fungal community diversity in B. syzigachne using 16S and internal transcribed spacer (ITS) rRNA sequencing. Significant differences were observed in bacterial community structure across four root-associated niches, with diversity decreasing from bulk soil to endosphere. The sensitive genotype exhibited higher bacterial diversity compared to the resistant biotype, indicating that sample type is the primary factor influencing microbial community composition, with genotype playing a secondary role. Additionally, we examined fungal communities in sensitive and resistant populations, identifying 271 fungal operational taxonomic units (OTUs). Ascomycota, Basidiomycota, and Rozellomycota were dominant in the sensitive population, while the resistant population contained two unique OTUs, Saccharomyces sp. and Apiotrichum montevideense, which were absent in the sensitive population. This study provides insights into how bacterial and fungal communities in B. syzigachne populations respond to herbicide exposure, contributing to a deeper understanding of weed–microbe interactions.