Bacterial volatile organic compounds for plant growth promotion under altered gravity conditions

Overview

This research investigates how volatile organic compounds (VOCs) emitted by plant growth-promoting rhizobacteria (PGPR) influence plant growth and health, particularly under altered gravity conditions relevant to space exploration. The project builds on established PGPR research and extends it into the unexplored area of airborne bacterial signaling molecules that promote plant development without direct physical contact.

The work has dual relevance: advancing fundamental understanding of plant-microbe interactions and supporting the development of biological growth-enhancement strategies for controlled environment agriculture, including potential space-based food production systems. Selected PGPR strains will be tested against leafy-green crops such as lettuce and spinach using partitioned plate systems that physically separate bacteria from plants, allowing only VOC-mediated effects.

Technical specifications

Research approach:

• Partition plate assays physically separate bacterial cultures from plant tissues, enabling isolation of VOC-mediated growth effects
• Clinostat-based altered gravity simulation using a 2-D rotation prototype already developed in-house, with planned 3-D rotational capability
• Selected PGPR strains from the principal investigator's characterized collection, some of which are already commercialized as agricultural inoculums
• Target crops include leafy greens such as lettuce and spinach, chosen for relevance to space agriculture and controlled environment production
• Assessment metrics focus on plant growth parameters following VOC exposure under both normal and altered gravity conditions

The study is designed to complete within approximately six months and requires a partnership capable of providing 3-D rotational clinostat testing infrastructure to complement the existing 2-D prototype.

Technology readiness level

The underlying PGPR strains have already been validated and commercialized as agricultural inoculums, demonstrating established efficacy for growth promotion and disease protection in staple crops. The VOC-specific mechanism represents an early-stage investigation, with foundational laboratory work completed and a working clinostat prototype in place. The next phase requires 3-D rotational testing capability, which is sought through partnership. The research is positioned at an early-to-mid technology readiness stage, with strong potential to inform both space agriculture applications and next-generation biological inputs for terrestrial controlled environment agriculture.