Effects of the Fungicide Propiconazole on Agronomic and Quality Traits of Hulled and Hulless Barley

Abstract

The hypocholesterolemic effect of hulless waxy barley (Hordeum vulgare L.) has increased its use in food products. Hulless cultivars currently grown in the Upper Midwest U.S. barley growing region are susceptible to a foliar disease, spot blotch, that can severely reduce yield. Spot blotch and kernel blight generally occur in the eastern area of the region; thus, hulless barley production is limited to the western area. Research on chemical control of spot blotch and kernel disease in hulless barley genotypes grown in the Upper Midwest has not been conducted. The objectives of this study were to determine whether natural field infections of the pathogen responsible for causing spot blotch and partly responsible for causing kernel blight similarly affect kernel and flour brightness of hulled and hulless barley genotypes, and to determine whether disease control with the fungicide propiconazole {1[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole} similarly affect agronomic and quality traits of hulled and hulless barley genotypes. Propiconazole reduced spot blotch severity. This resulted in increased yield and yield-related traits in hulled and hulless genotypes. Responses to propiconazole by the hulled and hulless genotypes were generally similar for spot blotch control, and similar for grain yield and 1000-kernel weight. The reduction in spot blotch severity did not result in brighter kernels or flour, nor did it affect mean total or soluble β-glucan content of hulled and hulless genotypes. Thus, hulless barley cultivars susceptible to spot blotch can be produced in the eastern area of the Upper Midwest barley growing region if they are protected with propiconazole.