| Abstract: | Several Fusarium species occurred abundantly in spring cereal seed samples studied in 1966, 1968 and 1972 in Finland. A total of 17 species of Fusarium were isolated and identified. The most frequently isolated species were F. avenaceum (Fr.) Sacc., F. culmorum (W. G. Sm.) Sacc., F. poae (Peck) Wr. and F. tricinctum (Cda) Sacc. These species were found in more than 40% of the seed samples from 1972. The same 4 Fusarium species in addition to F. graminearum Schwabe were used in the pathogenicity test. Artificially inoculated spring wheat and barley seeds were grown in the field during the growing season of 1973. Of these 5 species F. culmorum was clearly the most pathogenic. This species significantly lowered the shooting percentage and the yield of both cereals. Foot rot assessment also revealed F. culmorum as the most damaging species. Natural soil-borne infection obviously increased the foot and root rot, and thus the soil-borne F. culmorum strongly affected all treatments. In the harvested seed F. poae dominated in all treatments, but F. culmorum still occurred most abundantly in the seed lot harvested from plots originally inoculated with this species. |
