Attapulgite-Enhanced Ε-Poly-L-Lysine for Heightened Antibacterial Efficiency Against Pseudomonas Syringae Pv. Tomato

Abstract

ε-Poly-L-lysine (ε-PL) has emerged as a promising antimicrobial peptide for effectively combating various fungal plant diseases, showcasing remarkable antifungal activity and a high level of safety. However, its potential in addressing plant bacterial diseases has been relatively underexplored. This study focuses on assessing the efficacy of ε-PL and its nanomaterial derivative in the management of tomato bacterial spot disease caused by Pseudomonas syringae pv. tomato. The findings demonstrated that ε-PL can effectively inhibit the growth of Pseudomonas syringae pv. tomato. Furthermore, the loading of ε-PL onto attapulgite (referred to as ATT@PL) significantly augmented its impact on Pseudomonas syringae pv. tomato. Notably, ATT@PL with an ε-PL content of 18.15 μg/mL achieved a comparable antibacterial effect to that of ε-PL at a concentration of 100 μg/mL, which not only reduced the required dosage but also enhanced antibacterial efficacy. Additionally, ATT@PL activated the antioxidant system and salicylic acid pathway in tomatoes, empowering them to actively resist disease. Importantly, the nanoparticle pesticide loading system exhibited no adverse effects on seed germination and plant growth, underscoring its high safety profile. Our study highlighted the efficacy of ε-PL in controlling tomato bacterial spot disease and introduces a pesticide loading system to optimize its antibacterial efficiency. These findings align with the principles of green agriculture, offering promising applications across a broad spectrum of agricultural scenarios.

Keywords: tomato bacterial spot disease, ε-PL, attapulgite, antibacterial, improve efficiency