Response of Bacterial Community Structure and Function in Rhizosphere Soil on the Photosynthesis of Selected Plant Types C3 and C4 under Bis(2,4,6-tribromophenoxy) Ethane Exposure

Abstract

This study investigated the response of a bacterial community’s structure and function in the rhizosphere soil of C3 and C4 plants under bis(2,4,6-tribromophenoxy) ethane (BTBPE) exposure. The bacterial community composition was determined using 16S rRNA sequencing, while FAPROTAX and PICRUSt 2 were employed for functional predictions. Results showed significant differences between C3 and C4 plants in terms of bacterial community structure. C3 plants exhibited higher abundances of Proteobacteria, Bacteroidetes at the phylum level and Sphingomicrobium at the genus level, compared to C4 plants. Conversely, C4 plants had higher abundances of Actinobacteria and Patescibacteria at the phylum level and Nocardioides at the genus level. LEfSe and function prediction analyses revealed that the rhizosphere soil bacteria in C3 plants exhibited significantly higher enrichment in nitrogen fixation functions (p < 0.05), whereas C4 plants showed a significantly higher relative abundance of bacteria and functions related to organic pollutant degradation (p < 0.05). These findings suggest that the rhizosphere soil bacteria of C3 plants exhibit a stronger response to BTBPE exposure in nitrogen metabolism-related processes, while C4 plants possess superior biodegradation ability compared to C3 plants.