Silicon Control of Foliar Diseases in Monocots and Dicots

One of the most notable effects of silicon on plants is a reduction in the severity of multiple plant diseases caused by pathogenic organisms. For instance, the severity of several rice diseases, such as bacterial blight, brown spot, grain discoloration, leaf scald, leaf and panicle blast, stem rot and sheath blight were suppressed by applying silicon. The reduction in symptom expression is believed to be due to silicon’s effects on multiple defense mechanisms in rice that govern the latent period, lesion size, lesion number, and inoculum production. Although foliar-applied silicon is effective in reducing many foliar diseases, applying silicon to the roots is more effective because it mediates the plant’s defense responses to both foliar and root infections. Applications of silicon can perform as well as fungicides for suppressing plant diseases as well as enhance the resistance of susceptible cultivars to the same level as those that have complete genetic resistance. The application of silicon has value for inclusion in an integrated disease management strategy since this often overlooked, quasi-essential element clearly has the potential to reduced plant disease epidemics.