Antifungal Activity of Stabilized Ortho Silicic Acid (OSA) against Foliar Plant Pathogens

Abstract

Present study was aimed to evaluate antifungal activity of stabilized ortho silicic acid (OSA) against foliar pathogens under in vitro and in vivo conditions. Studies were conducted using a commercial formulation of stabilized ortho silicic acid (2.0%, Silixol™ OSA). Activity of OSA was evaluated on thirteen fungal pathogens (Alternaria alternata, Alternaria macrospora, Alternaria solani, Cercospora arachidicola, Colletotrichum gloeosporioides, Corynespora cassiicola, Curvularia lunata, Bipolaris sorokiniana, Mycosphaerella fragariae, Mycopshaerella musicola, Phoma obscurans, Phyllosticta arachidis-hypogaeae, and Pyricularia oryzae) using Poison Food Technique. Silixol OSA exhibited a differential activity against all test pathogens. Out of thirteen pathogens, eight exhibited more than 50% inhibition of mycelial growth. Silixol OSA had induced ultrastructure changes in both fungal mycelium and spores. Pathogens with more than 50% inhibition, based on Poison Food Technique, were tested further by in vivo studies. OSA sprayed plants had healthy leaves and exhibited less disease severity. Results of the present study elucidate potential application of stabilized OSA in Integrated Disease Management Program (IDMP) to avoid reliance on synthetic fungicides.