Fosfirend is a liquid formulation made in Chile that combines two active ingredients which are capable of inducing systemic acquired resistance (SAR) through complementary metabolic pathways in plant tissue. The first active ingredient is chitosan, a natural biopolymer derived both of king crab and snow chitin crab shells from Chile’s pristine waters in 12th Region. Both active ingredients-chitosan and potassium phosphite-are very potent SAR elicitors and both complement their effects between each other. Potassium phosphite has an important systemic capacity to induce SAR from the inside of the tissue outwards, whereas chitosan, the larger molecule, has less systemic capacity and, therefore, primarily induces SAR inwards from external tissue layers.

While the metabolic pathways are different, they converge at the same response gene, releasing a more potent synergetic signal. Phytoalexins, chitinases, anti-stress proteins and endogenous growth phytohormones are produced.