Exogenous γ-aminobutyric acid and Bacillus pumilus reduce arsenic uptake and toxicity in rice

Journal article

Authors/Editors

RUJIRA DOLPHEN

Strategic Research Themes

Publication Details

Author list: Dolphen, Rujira; Thiravetyan, Paitip

Publisher: Springer

Publication year: 2024

Journal acronym: Environ Sci Pollut Res

Volume number: 31

Issue number: 7

Start page: 10609

End page: 10620

Number of pages: 12

ISSN: 0944-1344

eISSN: 1614-7499

URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85184518613&doi=10.1007%2fs11356-024-31893-2&partnerID=40&md5=01111853bace15e82e3d52d1b6c90821

Languages: English-Great Britain (EN-GB)

View on publisher site

Abstract

In this study, the addition of γ-aminobutyric acid (GABA), Bacillus pumilus, or both, was found to enhance rice growth and yield while significantly decreasing arsenic (As) accumulation in Oryza sativa rice tissues. GABA emerged as a regulator of iron (Fe) homeostasis, acting as a signaling modulator that influenced phytosiderophore secretions in the plant. Meanwhile, B. pumilus directly increased Fe levels through siderophore production, promoting the development of Fe-rich rice plants. Subsequently, Fe competed with As uptake at the root surface, leading to decreased As levels and translocation to the grains. Furthermore, the addition of GABA and B. pumilus optimized rice indole-3 acetic acid (IAA) contents, thereby adjusting cell metabolite balance under As stress. This adjustment results in low malondialdehyde (MDA) contents in the leaves and roots during the early and late vegetative phases, effectively reducing oxidative stress. When added to As-contaminated soil, GABA and B. pumilus effectively maintained endogenous GABA levels and exhibited low ROS generation, similar to normal soil. Concurrently, GABA and B. pumilus significantly downregulated the activity of OsLsi1, OsLsi2, and OsABCC1 in roots, reducing As uptake through roots, shoots, and grains, respectively. These findings suggest that GABA and B. pumilus additions impede As translocation through grains, ultimately enhancing rice productivity under As stress. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.

Keywords

Arsenic-contaminated soil, Iron