Effect and mechanism of NaHS on tobacco bacterial wilt caused by Ralstonia solanacearum

Abstract

Since its discovery as a third unique gaseous signal molecule, hydrogen sulfide (H2S) has been extensively employed to resist stress and control pathogens. Nevertheless, whether H2S can prevent tobacco bacterial wilt is unknown yet. We evaluated the impacts of the H2S donor sodium hydrosulfide (NaHS) on the antibacterial activity, morphology, biofilm, and transcriptome of R. solanacearum to understand the effect and mechanism of NaHS on tobacco bacterial wilt. In vitro, NaHS significantly inhibited the growth of Ralstonia solanacearum and obviously altered its cell morphology. Additionally, NaHS significantly inhibited the biofilm formation and swarming motility of R. solanacearum, and reduced the population of R. solanacearum invading tobacco roots. In field experiments, the application of NaHS dramatically decreased the disease incidence and index of tobacco bacterial wilt, with a control efficiency of up to 89.49%. The application of NaHS also influenced the diversity and structure of the soil microbial community. Furthermore, NaHS markedly increased the relative abundances of beneficial microorganisms, which helps prevent tobacco bacterial wilt. These findings highlight NaHS's potential and efficacy as a powerful antibacterial agent for preventing tobacco bacterial wilt caused by R. solanacearum.

Combined In Silico and In Vitro Study to Reveal the Structural Insights and Nucleotide-Binding Ability of the Transcriptional Regulator PehR from the Phytopathogen Ralstonia solanacearum

“…The devastating soil-borne disease known as bacterial wilt is prevalent worldwide and affects hundreds of plant species, particularly several important crops in the Cucurbitaceae and Solanaceae families . Bacterial wilt is a factor in the deterioration of soil, poor plant development, excess of harmful bacteria, and disease outbreaks that are spread through the soil . This has led to the theory that wilting results from an altered ecological balance between plants and rhizosphere microorganisms .…”

“… 1 Bacterial wilt is a factor in the deterioration of soil, poor plant development, excess of harmful bacteria, and disease outbreaks that are spread through the soil. 2 This has led to the theory that wilting results from an altered ecological balance between plants and rhizosphere microorganisms. 3 Due to the wide geographical distribution of Ralstonia solanacearum , the existence of numerous variants, its persistence, and the wide variety of hosts it affects, bacterial wilt control has been a problem on a global scale without any practical solutions having been developed.…”