Brown alga Ascophyllum nodosum extract-based product, Dalgin Active®, triggers defense mechanisms and confers protection in both bread and durum wheat against Zymoseptoria tritici

Abstract

Alternative control strategies are increasingly encouraged to develop sustainable crop protection. In this aim, we assessed the ability of Dalgin Active®, an Ascophyllum nodosum extract-based product, to induce resistance in bread wheat and durum wheat against Zymoseptoria tritici, a major fungal pathogen on these crops. Foliar application of the product provided a strong and significant reduction of disease intensity on both wheat species without any direct effect against the pathogen. Infection process monitoring revealed that Dalgin Active® did not prevent fungal epiphytic growth and leaf colonization, but its application results in an inhibition of sporulation as well as fungal cell wall-degrading enzyme and protease activities. During the early stages of infection, Dalgin Active® activated several plant defense markers on both wheat species, including PR protein, antioxidant metabolism, phenylpropanoid, and octadecanoid-based pathways. Although few differences were recorded, the induced defense reaction patterns were overall similar in both wheat species, suggesting that Dalgin Active® could be used to biocontrol Z. tritici on both crops.