P-524 - Investigating the role of trans-cinnamic acid in soybean defense against white mold

Sclerotinia sclerotiorum, also known as white mold, is a highly destructive fungal pathogen that can lead to significant crop losses in soybeans. Soybeans are vital for promoting global food security; therefore, finding solutions to combat white mold is essential for feeding a rapidly growing population. Current management heavily relies on chemical fungicides, which exacerbate environmental pollution. Utilizing naturally occurring secondary metabolites produced in soybeans offers a promising approach to enhance food production without increasing acreage and reducing dependence on chemical fungicides. One such secondary metabolite is trans-cinnamic acid (CA), which is produced in the phenylpropanoid pathway and serves as a precursor for the key defense hormone, salicylic acid (SA). Previous studies found that partially resistant soybean lines quickly accumulate CA following S. sclerotiorum infection versus susceptible lines. In our work, we have found that CA possesses strong inhibitory properties against the germination and growth of S. sclerotiorum in vitro. Furthermore, by treating soybean leaves with CA, we have shown that SA-responsive genes are induced in the absence of S. sclerotiorum, indicating that CA may prime the immune system. We are currently performing transcriptomic and metabolomic studies to elucidate the physiological responses induced by CA treatment to enhance the natural defense mechanisms of soybeans. These studies will pave the way to reducing our reliance on chemical fungicides while maintaining yield potential in the face of white mold disease.