Resistance to rice blast induced by ferric chloride, di-potassium hydrogen phosphate and salicylic acid

Abstract

Ferric chloride, di-potassium hydrogen phosphate and salicylic acid were tested for their capacity to suppress rice blast under greenhouse and field conditions. In greenhouse experiments, the chemicals significantly reduced disease severity when applied as a soil drench, thus demonstrating a systemic effect. Foliar spray, but not seed treatment, also caused a reduction in blast severity. In field experiments conducted at two locations in Nepal, neck blast incidence was significantly reduced by all three chemicals when applied as a foliar spray at least two times from the seedling to the heading growth stage. The greatest reduction in blast incidence was obtained with ferric chloride. Grain yield was significantly increased by all chemicals in one of the experiments which included five sprays from seedling to heading growth stages. In another experiment, that included combinations of sprays at different growth stages, only ferric chloride significantly increased the grain yield. Previous studies suggest that blast control involves induced resistance from the applied chemicals.