目前,日本北海道一带广泛分布着由Fusa—rium nivale(=Gerlachia nivalis)引致的秋播小麦红色雪腐病。该病一般多见于多雪地带排水良好的地里,但冻土地带也常在多雪年份或多雪地里严重发生。1973年以来一直使用甲基托布津(以下称TM)防治该病有效。然而,在1981年春季,发现前一年秋季已喷药的地块,成片或零星发病较往年增多,还 At present, autumnal wheat red snow rot caused by Fusa-rium nivale (= Gerlachia nivalis) is widely distributed in the area of ​​Hokkaido, Japan. The disease is more commonly found in well-drained areas of the snowy areas, but the frozen terrain is also often severely affected in snowy or snowy conditions. The use of thiophanate-methyl (hereinafter TM) has been shown to be effective in preventing and treating this disease since 1973. However, in the spring of 1981, the plots that were sprayed in the autumn of the previous year were found to have become more sporadic or sporadic than in previous years.