Control of sesame bacterial leaf spot with copper fungicides

Abstract

In recent years, Mie Prefecture has been working to establish a domestic production area for sesame (Sesamum indicum L.), and the cultivation area has been increasing. Meanwhile, there is a wide incidence of sesame bacterial leaf spot (caused by Pseudomonas syringae pv. sesami Young, Dye & Wilkie, Acidovorax valerianellae Gardan, Stead, Dauga & Gillis, and Xanthomonas sp.), contributing to yield loss. No pesticides against the disease are currently registered in Japan, and no control measures have been established. We evaluated three copper fungicides (basic copper sulfate, sodium bicarbonate/anhydrous copper sulfate, and basic copper chloride/sulfur) in pot and field tests. Our results demonstrated that all fungicides could suppress the disease when applied before its onset or in its early stage.