مشخصات پژوهش

Background Entomopathogenic nematodes (EPNs) are widely recognized as an effective biological control agent, but their practical application is often limited by challenges in formulation stability and survival during storage. This study investigated the combined effects of carboxymethyl cellulose (CMC) concentrations, storage temperatures, storage periods, and antimicrobial agents on the survival and infectivity of formulated infective juveniles (IJs) of Stein- ernema carpocapsae. The goal is to optimize EPN formulations for enhanced shelf life and efficacy, addressing a critical gap in biocontrol strategies. Results The study employed a comprehensive factorial experimental design to evaluate the interactions between these variables over a 6-month storage period. Results demonstrated that lower CMC concentrations (2 and 3%) combined with lower storage temperatures (11 °C) significantly enhanced IJ survival. Among antimicrobial agents, sorbic acid and yarrow extract emerged as the most effective, with survival rates exceeding 80% under opti- mal conditions. In contrast, the peroxide + formaldehyde combination consistently resulted in significantly reduced survival, particularly at higher CMC concentrations (5%) and longer storage times (6 months). The highest survival rates of IJs were observed with yarrow extract at 2% CMC (98.607%) and sorbic acid at 4% CMC (100%), while the low- est survival rates were recorded with peroxide + formaldehyde at 5% CMC (0.00%). Conclusions This study is the first to systematically evaluate the synergistic effects of CMC, antimicrobial agents, and storage conditions on EPN survival, offering a robust framework for developing stable and effective formulations. The findings provide practical insights for optimizing EPN-based biocontrol strategies and highlight the importance of selecting appropriate formulation components to enhance the shelf life and efficacy of S. carpocapsae. These results have significant implicated for improving th