Fungicidal efficacy of oxysilver nitrate and sodium diperiodatoargentate (III) for control of seed-borne and foliar diseases
M. W. HARDING (1), R. J. Howard (2), M. E. Olson (3)
(1) Innovotech Inc., Brooks, AB, CANADA; (2) Alberta Agriculture and Rural Development, Brooks, AB, CANADA; (3) Innovotech Inc., Edmonton, AB, CANADA
Phytopathology 101:S69

Silver and oxidized silver compounds have recently been shown to be effective plant disease management tools. For example, some non-oxidized silver compounds are effective fungicides when applied to inoculated foliage. Oxidized forms of silver (e.g. oxysilver nitrate) also have significant potential in crop protection, particularly as seed treatments for eradicating seed-borne bacteria and fungi on pulses and other crops. We report here that oxidized silver compounds, oxysilver nitrate and diperiodatoargentate (III), are potential disease management tools for field and horticultural crops as seed treatments and foliar-applied fungicides. In replicated, small-plot field trials, oxysilver nitrate was shown to reduce seed piece decay (Fusarium sambucinum) on potato. Furthermore, both oxysilver nitrate and sodium diperiodatoargentate (III) reduced foliar diseases on field crops including Ascochyta blight (Ascochyta rabei) on chickpea and white mould (Sclerotinia sclerotiorum) on dry bean. The ability of oxidized silver compounds to reduce disease symptoms was especially evident when tank mixed with other commercially available fungicides such as Bravo^®500 and Allegro^®500F. In tank-mixed treatments enhanced, and perhaps synergistic, efficacy was observed.