Biological control agent optimization for greenhouse crop production

Overview

This research addresses a critical gap in greenhouse agriculture: understanding why commercially available biological control agents (BCAs) often fail to deliver expected plant growth and disease suppression benefits under the nutrient-rich, well-managed conditions typical of intensive greenhouse production. By analyzing how growing media composition affects BCA performance, this work aims to develop reproducible protocols for producing synergistic BCA culture extracts that deliver consistent results in commercial greenhouse environments. The ultimate goal is to enable growers to minimize fertilizer inputs while maximizing BCA activity, yield, and disease suppression.

Technical specifications

Research approach and findings:

• Comparative analysis of three growing media types: virgin (VS), spent (NPS), and pasteurized (PS), evaluated for pH, cation exchange capacity (CEC), total carbon content, organic material, macronutrients, and micronutrients using standard soil analysis and Mehlich III extraction methods
• Spent media (NPS) consistently showed higher macro and micronutrient levels but lower organic material and carbon content compared to virgin media
• Next-generation 16S rRNA sequencing revealed that five bacterial phyla dominate virgin media: Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, and Cyanobacteria, while pasteurized and spent substrates showed higher DNA copies of Proteobacteria
• Planned application of commercially available BCAs and BCA culture extracts (BCA-E) to test plants under varying conditions of growing media pH, nutrient levels, and disease pressure
• Measurement of crop growth, yield, disease incidence, and soil microbiome composition under normal greenhouse conditions
• Development of dynamic models to balance soil pH, nutrition, and BCA activity for optimal productivity
• Database analysis of BCA-E to identify and develop active component mixtures

Key value for industry partners:

• Potential reduction in fertilizer inputs through optimized BCA integration
• Improved disease suppression in commercial greenhouse operations
• Standardized, reproducible protocols for synergistic BCA extract production

Technology readiness level

This research is currently at an early-to-mid stage of development. Initial characterization of growing media and baseline microbiome analysis has been completed, establishing foundational data on how different substrate types influence bacterial community composition. Future validation steps include controlled greenhouse trials applying BCAs and BCA culture extracts under varying environmental conditions, development of dynamic predictive models, and formulation of synergistic commercial-ready products. The work is positioned to transition from laboratory validation to applied greenhouse testing, with potential for commercial protocol development.