# Unveiling Metal Tolerance Mechanisms in Leersia hexandra Swartz under Cr/Ni Co-Pollution by Studying Endophytes and Plant Metabolites

## TL;DR

This study explores how Leersia hexandra and its endophytic bacteria respond to chromium and nickel pollution, revealing new insights into plant tolerance mechanisms.

## Contribution

The study identifies specific endophytic bacteria and their role in promoting plant metabolite production under heavy metal stress.

## Key findings

- Chryseobacterium and Comamonas show remarkable tolerance to chromium and nickel co-pollution.
- Endophytic bacteria are linked to increased production of carbohydrates, flavonoids, and amino acids in L. hexandra.
- The findings suggest new bioremediation strategies using plant-endophyte interactions for heavy metal pollution.

## Abstract

Heavy metal pollution poses significant environmental challenges, and understanding how plants and endophytic bacteria interact to mitigate these challenges is of utmost importance. In this study, we investigated the roles of endophytic bacteria, particularly Chryseobacterium and Comamonas, in Leersia hexandra Swartz (L. hexandra) in response to chromium and nickel co-pollution. Our results demonstrated the remarkable tolerance of Chryseobacterium and Comamonas to heavy metals, and their potential to become dominant species in the presence of co-pollution. We observed a close relationship between these endophytic bacteria and the significant differences in metabolites, particularly carbohydrates, flavonoids, and amino acids in L. hexandra. These findings shed light on the potential of endophytic bacteria to promote the production of aspartic acid and other metabolites in plants as a response to abiotic stressors. Furthermore, our study presents a new direction for plant and bioremediation strategies in heavy metal pollution and enhances our understanding of L. hexandra’s mechanisms for heavy metal tolerance.