Plant-Derived Essential Oils and Aqueous Extract as Potential Ingredients for a Biopesticide: Phytotoxicity in Soybean and Activity against Soybean Mosaic Virus

CAREZZANO, MARÍA EVANGELINA; REYNA, PABLO GASTÓN; ACCOTTO, EFRÉN; GIORDANO, WALTER; OLIVA, MARÍA DE LAS MERCEDES; RODRIGUEZ PARDINA, PATRICIA; SABINI, MARÍA CAROLA

Processes

MDPI

Año: 2023 vol. 11

As a follow-up to previous studies, the effects of Thymus vulgaris essential oil (TEO) on selected virulence factors (growth, sessile cell survival, swimming, swarming, and exopolysaccharide production) were evaluated in phytopathogenic Pseudomonas syringae strains isolated from soybean fields in Argentina. P. syringae is responsible for bacterial blight, a disease that affects crops worldwide. Plant bacterioses are usually treated with antibiotics and copper compounds, which may contribute to the development of resistance in pathogens and damage the environment. This is why eco-friendly alternatives are necessary. Although aromatic plants are a natural source of antimicrobial substances, the effects of such substances on phytopathogenic bacteria remain largely unexplored. Subinhibitory concentrations of the oil significantly reduced the slope and rate of bacterial growth. In addition, biofilm and EPS production were inhibited and swimming and swarming motility patterns were affected, at all the oil concentrations tested. Therefore, TEO could potentially be a highly efficient antipseudomonal agent to treat plant infections caused by P. syringae.