Reaction of seedling roots of 14 crop species toFusarium graminearumfrom wheat heads

Abstract
To increase our understanding of the epidemiology of fusarium head blight of wheat and barley, a study was conducted under controlled conditions to determine whether Fusarium graminearum Schwabe from wheat can cause seedling blight or root rot in various crop species. Inoculum of F. graminearum, consisting of a wheat floret infected with the pathogen, was placed adjacent to surface-sterilized seed of each crop in a sterile potting mix. Wheat, barley, oat, rye, triticale, canaryseed, flax, canola (Brassica napus L. and Brassica rapa L.), mustard, bean, field pea, lentil, and chickpea were included in the study. Seedling emergence and root rot severity were scored at 3–4 weeks after seeding. The effect of temperature on seedling blight severity was also tested in barley cv. Brier. Inoculation reduced emergence in all crops, except canola, mustard, and field pea, and increased root rot severity in most crops. Emergence of seedlings was not affected at the lowest temperature (10:5°C day:night) and no root infection occurred. However, as the temperature increased from 10 to 30°C, seedling emergence and establishment were reduced and root rot severity increased. Infection of roots, crowns, and seedlings of the crops grown in rotation with wheat indicates that these crops may act as alternative hosts to F. graminearum.