一、发病情况:华北栽培洋麻,已有十二、三年的历史,幼苗子叶上及生长期内叶上的炭疽病斑,过去虽常年发生,但以烂头为特征的炭疽病却未发现。去年茶淀清河农场的1,011亩洋麻,5月上旬幼苗出土后,即遭受炭疽病菌为害,倒伏死亡。重种的洋麻,出苗后亦复死亡,最后全部麻田旱直播水稻。6月初旬我所洋麻试验地内,发现烂头病株,尤以山东高秆种最为严重。天津杨柳青农场的1,100亩洋麻6月中下旬开始发病,7月初旬即全部烂头,毁种蔬 First, the incidence: Keni cultivation in North China, has 12 or three years of history, seedlings and leaves on the cotyledons in the anthracnose spot, although perennial occurred, but the rotten head characterized by anthrax has not Find. Last year, 1,011 mu of Chajianhehe farm was planted. After the seedlings were excavated in early May, they were injured by anthrax and died of lodging. Heavy seed of kenaf, seedlings also die after the death, and finally all Arida direct broadcast of rice. In early June, in my experiment of kenaf, we found the rotten plants, especially the tall stalks in Shandong. Tianjin Yangliuqing 1,100 acres of kenaf farm began in late June incidence, early July that is all rotten, destroyed species of vegetables