Application of Pseudomonas spp. for control of plant diseases in hydroponic systems

Project SummaryCrazy Root (CR) disease (caused by Agrobacterium rhizogenes) has recently beenrecognized as an emerging disease particularly in greenhouse hydroponic tomato production.There is currently no commercial product for control of CR disease.Newly emerging diseasessuch as CR disease and more common oomycetic root-rot diseases (such as those caused byPythium spp.) can easily spread throughout an entire hydroponic system leading to plant declineand significant yield loss for the grower.Consequently growers must sterilize or throw away allinfected materials leading to added expenses and operational downtime. The potential utility ofbeneficial microorganisms for the sustainable enhancement of vegetable production is wellestablished in the research literature.While use of biocontrol in greenhouses continues toincrease; however a significant problem in the expanding biologicals market is inconsistentperformance of microbial products.3Bar Biologics is bringing to market a novel beneficial microbe delivery system toimprove sub-optimal inconsistent performance of microbial products.The delivery system iseasily activated on-site by the grower by simply pushing a button to combine the stabilizedbacteria inoculum with the liquid growth medium.3Bar's disposable bioreactor technologyopens up the potential for growers to apply more effective microbial strains with CR controlcapability.Discovery research at The Ohio State University identified several Pseudomonasstrains capable of CR disease control.Phase I findings support the commercial potential forbiocontrol of CR disease consistently showing 60-70%+ reduction of CR disease on tomato in apilot hydroponic system using the Pseudomonas strains produced in 3Bar's delivery system.Thedelivery system enables a low cost fast route for product development scale-up andbiomanufacturing to accelerate commercialization.Building on Phase I efforts the proposed Phase II expected outcomes will includereducing to practice application of the microbe technology in a production setting to create labeland use instructions for product registration.In parallel scaling up of the formulation andprocesses for pilot manufacturing will be further developed. The proposed work addresses fourkey technical objectives for achieving commercialization: i) demonstrate product stability underlonger term/broader range of conditions ii) scale-up processes for biomanufacturing iii) defineproduct label and use instructions and iv) demonstrate consistent product performance for CRdisease control in commercial hydroponic production to support product registrations andmarketing materials.Additionally research will be expanded to demonstrate potential forapplication to additional hydroponic vegetable crops and against other common fungal/oomyceteroot rot diseases with the ultimate goal of developing a broad-spectrum biocontrol product.The proposed project is directly aligned with USDA's priorities in addressing climatechange via climate-smart agriculture and tackling food insecurity (through application of moresustainable bio-based practices in hydroponic production systems) and SBIR Priority 8.2 toresearch bio-based approaches for plant protection against abiotic and biotic stresses.