Fluorescent Mesoporous Silica Nanoparticles for Targeted Tebuconazole Delivery Against Brown Root Rot in Rubber Trees

Brown root rot, caused by Phellinus noxius, is a major threat to rubber tree cultivation, resulting in substantial economic losses. Traditional control methods, such as root irrigation with fungicides, are labor-intensive, water-consuming, and inefficient, particularly in regions with limited water resources. This study introduces fluorescent mesoporous silica nanoparticles (FL-MSNs) as a novel delivery platform for tebuconazole to target P. noxius infection. The nanoparticles, with a high fungicide loading efficiency (43.81%), exhibit controlled release under varying pH conditions, providing sustained tebuconazole delivery. Fluorescent labeling allowed tracking of the nanoparticles, confirming effective transport from leaves to roots via phloem. Greenhouse trials demonstrated that foliar application of Teb@FL-MSNs resulted in an 84% survival rate of infected seedlings, significantly outperforming untreated controls, which exhibited 100% mortality. The nanoparticle formulation also reduced lesion size, highlighting its potential to improve disease control while minimizing fungicide use. These findings emphasize the advantages of Teb@FL-MSNs over traditional methods, offering a more efficient, environmentally friendly, and sustainable approach to managing brown root rot in rubber plantations.