(621d) Optimization of Lignocellulose-Based Production of Biocontrol Agents As Biorefinery Coproducts

Over 80% of Fusarium sambucinum, causative of potato dry rot, are now resistant to the fungicide thiabendazole which was once used for disease control. ARS (Peoria, IL) has developed three Pseudomonas spp. as biological control agents (BCAs) to serve as alternatives to traditional chemicals for controlling potato dry rot and other maladies, including sprouting, late-blight (incited by Phytophthora infestans), pink rot (incited by Phytophthora erythroseptica), and leak (incited by Pythium ultimum). It is proposed that such Pseudomonas spp., which utilize diverse carbon sources, can be developed as valuable coproducts for the lignocellulose biorefining industry. Our recent results suggest that sugars, acetic acid, and furan aldehydes generated from lignocellulose can all be utilized during production of these BCAs. Data will be presented showing BCA viable cell yield and productivity optimization on dilute acid switchgrass hydrolysate as a function of sugar loading, C:N ratio, oxygen transfer rate, phosphate (pH) and growth factor levels. Optimization of the inoculum needed for production of triculture with balanced growth of three Pseudomonas strain populations will also be presented, along with a rehydration technique for recovering viable cell activity in dried cell formulations and an evaluation of bio-efficacy in Fusarium dry rot suppression.