Field evaluation of a derivative of 1,4-oxathiin for control of cereal smuts

Abstract

In semi-commercial field trials, the systemic cereal seed fungicide Vitavax (2,3-dihydro-5- carboxanilido-6-methyl-1,4-oxathiin) gave excellent control of natural loose smut infections of wheat and barley; combining it with phenylmercuric acetate reduced its efficacy on loose smut of wheat. In an irrigated row-plot trial, using wheat artificially inoculated with loose smut, Vitavax at the recommended rate was only moderately effective ; at half rate disease control was unsatisfactory. Vitavax was tested on three collections of common bunt of wheat. On all three it was better than Ceresan. It was inferior to hexachlorobenzene on two collections, but on the third, resistant to hexachlorobenzene, it was much superior. Vitavax gave excellent control of covered smut of oats whereas Panogen and Ceresan were much less effective.