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

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. <i>Beckmannia syzigachne</i>, a problematic weed, reduces crop yield and quality. In this study, we investigated bacterial and fungal community diversity in <i>B. syzigachne</i> 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). <i>Ascomycota</i>, <i>Basidiomycota</i>, and <i>Rozellomycota</i> were dominant in the sensitive population, while the resistant population contained two unique OTUs, <i>Saccharomyces</i> sp. and <i>Apiotrichum montevideense</i>, which were absent in the sensitive population. This study provides insights into how bacterial and fungal communities in <i>B. syzigachne</i> populations respond to herbicide exposure, contributing to a deeper understanding of weed-microbe interactions.