Mycoherbicide using exserohilum rostratum Y9511 for biological weed control in rice fields

Overview

This solution offers a biological weed control approach for rice production using a mycoherbicide developed from the fungal strain Exserohilum rostratum Y9511. The product targets Leptochloa chinensis (Chinese sprangletop), a problematic weed in rice fields that competes with crops for nutrients, water, and sunlight.

Laboratory pathogenicity tests demonstrated that the fungal strain achieved 100% control of Leptochloa chinensis after 21 days of treatment, measured by both plant count and fresh weight reduction. Safety evaluations confirmed that the mycoherbicide does not infest nine major crops including rice, wheat, and soybeans, making it suitable for integration into rice cropping systems.

The solution addresses the growing need for sustainable weed management alternatives that reduce reliance on chemical herbicides, lower environmental impact, and support ecological balance in agricultural ecosystems.

Technical specifications

Active ingredient: Exserohilum rostratum strain Y9511, a pathogenic fungus isolated from susceptible Leptochloa chinensis plants.

Identification methods:

• Morphological analysis of conidia and mycelium
• rDNA ITS gene sequencing
• Brn1 gene sequencing

Efficacy data:

• 100% control effect on Leptochloa chinensis after 21 days
• Measured by reduction in plant number and fresh weight

Safety profile:

• Mild acute oral toxicity in rats
• Mild acute inhalation toxicity in rats
• Low transdermal toxicity in rats
• No skin allergic reactions
• No skin irritation
• Mild eye irritation without washing after exposure
• No significant impact on silkworms, bees, or birds

Crop compatibility: Confirmed safe for rice, wheat, soybeans, and six other crops.

Technology readiness level

The mycoherbicide is currently at an advanced laboratory validation stage. The fungal strain has been isolated, identified through multiple methods, and proven effective in controlled pathogenicity tests. Animal safety testing and environmental risk assessments have been completed with favorable results.

Next steps toward commercialization include field plot trials required for product registration, isolation and purification of herbicidal metabolites, metabolome analysis to identify active compounds, and clarification of toxin synthesis and pathogenic mechanisms. The research team estimates approximately one year to complete these validation activities and is seeking partnerships to support field trials, metabolite analysis, and funding for key personnel.