PGPR biocontrol seed treatment for soilborne pathogen rhizoctonia solani in peanuts

Overview

This research proposes the development of plant growth promoting rhizobacteria (PGPR) as a novel biological seed treatment to control the soilborne fungal pathogen Rhizoctonia solani in peanuts. Current disease management relies on conventional fungicides such as Rancona V PD and Dynasty, but no biological control options currently exist for peanut seed rots and damping-off. By leveraging Bacillus species and other spore-forming bacteria that remain stable over long storage periods, this approach aims to provide growers with an effective, sustainable biocontrol alternative that also promotes overall plant growth and health.

Technical specifications

Key features:

• Application of PGPR strains as seed treatments to suppress R. solani infection in peanut seedlings
• Focus on spore-forming Bacillus species for shelf-stable formulation suitable for commercial seed treatment
• Evaluation of individual strains, species, and combinations to identify the most effective formulations
• Greenhouse screening using susceptible peanut variety 'Georgia 06G' inoculated with R. solani to measure seed rot incidence and damping-off severity
• Comparison against commercial fungicide seed treatments and nontreated controls
• Builds on prior research showing Bacillus pumilus INR7 induces plant defense responses against multiple pathogens in cucumber

Research approach:

• Initial greenhouse screening of diverse PGPR strains, species, and mixtures
• Assessment of treated seed for disease suppression and plant growth promotion
• Selection of most promising candidates for subsequent field trials

Technology readiness level

This research is at an early stage of development. PGPR strains with demonstrated plant defense properties in other cropping systems have not yet been evaluated for control of soilborne peanut diseases. The proposed validation involves a one-year greenhouse screening phase to identify the most promising PGPR candidates, with field experiments planned as the next step. The technology has strong potential for commercialization as a biological seed treatment product pending successful greenhouse and field validation.