Preparation and bud-inhibiting efficacy evaluation of three bio-alcohol-based tobacco bud inhibitor emulsifiable concentrates

Three types of bio-alcohol-based emulsifiable concentrates (EC) for tobacco bud inhibition were prepared, and their properties, dilution characteristics, and field bud inhibition effects were systematically evaluated. Specificlly, lauryl alcohol, myristyl alcohol, and C₁₂-C₁₄ mixed alcohol served as raw materials, which were proportionally blended with solvents, and additives to formulate the emulsifiable concentrates. Their properties were characterized by stability evaluation, particle size analysis, and determinations of surface tension, contact angle and retention rate. Their bud-inhibiting efficacy was evaluated via field efficacy trials. The results indicated that all three bio-alcohol-based tobacco bud inhibitors exhibited good storage stability, forming uniform emulsions upon dilution with surface tensions consistently below 30 mN/m. They demonstrated strong wettability, with contact angles of droplets on tobacco axillary buds remaining below 35°, alongside superior adhesion properties, achieving retention amounts exceeding 0.02 g/cm². Post-topping inhibition tests indicated that the C₁₂-C₁₄ mixed alcohol and myristyl alcohol inhibitors, applied at dilutions of 25-fold and 50-fold, respectively, provided sustained and effective bud inhibition at both 20 and 40 days after treatment. Notably, the C₁₂-C₁₄ mixed alcohol inhibitor EC at a 25-fold dilution achieved a bud inhibition rate of 91.06% and a bud inhibition efficacy of 97.61% at 40 days after application, significantly outperforming the chemical control, 25% flumetralin EC. While the lauryl alcohol-based inhibitor showed good initial efficacy but limited persistence. This study suggests that bio-alcohol-based tobacco bud inhibitors offer significant advantages in both bud-inhibiting efficiency and application safety, highlighting their potential as eco-friendly alternatives to traditional chemical agents for sustainable tobacco production.