Gluconic acid as a biocontrol active ingredient against Fusarium diseases and mycotoxin biosynthesis

Overview

This research proposes gluconic acid (GlcA), produced naturally by Pseudomonas bacteria, as a novel active ingredient for controlling Fusarium diseases and reducing mycotoxin biosynthesis in wheat. Fusarium pathogens such as Fusarium graminearum raise the pH of host plant tissue during infection, a process linked to disease severity and the production of deoxynivalenol (DON), a harmful mycotoxin. By counteracting this alkalinization, gluconic acid offers a targeted biological strategy to protect crops, reduce yield losses, and improve food safety.

Technical specifications

• Mechanism of action: Gluconic acid lowers the pH of plant tissue, counteracting the alkalinization induced by Fusarium pathogens during infection
• Biocontrol agent: Isolated Pseudomonas strains from wheat that produce gluconic acid via the enzyme glucose dehydrogenase (encoded by the gcd gene), which oxidizes D-glucose into gluconic acid
• Validation results: Wild-type Pseudomonas sprayed on wheat leaves significantly lowered host pH, reduced DON production, and alleviated disease symptoms compared to a gcd-deletion mutant unable to produce gluconic acid (p<0.05)
• Future development: Direct application of gluconic acid to wheat heads and seedling leaves, investigation of systemic resistance induction, construction of synthetic microbial communities using high GlcA-producing Pseudomonas strains, and evaluation in greenhouse and field experiments
• Target crops: Wheat
• Target pathogens: Fusarium graminearum and related Fusarium species
• Target toxins: Deoxynivalenol (DON) and related mycotoxins

Technology readiness level

The technology is at an early-to-mid stage of development. Laboratory validation on wheat leaves has confirmed that Pseudomonas-derived gluconic acid inhibits Fusarium-induced alkalinization, reduces DON mycotoxin production, and decreases disease symptoms. Next steps include direct spraying of gluconic acid on wheat, construction of optimized synthetic microbial communities, and greenhouse and field trials to evaluate efficacy under realistic agricultural conditions.